# 9 Gastrointestinal endoscopy

# Aspirin

Aspirin

Aspirin and NSAIDs inhibit platelet cyclo-oxygenase, resulting in suppression of  thromboxane A -induced platelet aggrega - 2 tion. Limited published data do not suggest an increased bleed - ing risk in patients taking standard doses and, therefore, there is no need to discontinue therapy before endoscopic procedures. Aspirin

Aspirin and NSAIDs inhibit platelet cyclo-oxygenase, resulting in suppression of  thromboxane A -induced platelet aggrega - 2 tion. Limited published data do not suggest an increased bleed - ing risk in patients taking standard doses and, therefore, there is no need to discontinue therapy before endoscopic procedures. Aspirin

Aspirin and NSAIDs inhibit platelet cyclo-oxygenase, resulting in suppression of  thromboxane A -induced platelet aggrega - 2 tion. Limited published data do not suggest an increased bleed - ing risk in patients taking standard doses and, therefore, there is no need to discontinue therapy before endoscopic procedures.

# COLONSCOPY

COLONSCOPY

- Early attempts at colonoscopy were hindered by poor technique and limitations of available instruments. The ability to steer an endoscope around the entire colon and into the terminal ileum was made possible by the development of  fully flexible colonoscopes with >90° angulation of  the tip. Advances in - bowel preparation have enhanced mucosal visualisation. Understanding two key technical aspects of  colonoscopy allows a greater caecal intubation rate and ileal intubation tic with minimal discomfort using light sedation. The first is that continued inward pressure of  the endoscope results in loop formation within the mobile sigmoid and transverse colon, which in turn leads to paradoxical movement and loss of  fine tip control. The second is that pulling back the scope regularly with appropriate torque to ensure a straight passage through the sigmoid colon and around the splenic flexure greatly aids the completion of  right-sided examination. Endoscopic navigation systems such as Scope Guide (Olympus) and Scope Pilot (Pentax) can help to characterise the nature of  the loop, allowing for more accurate loop reso - lution techniques. Increasing the sti ff ness of  the colonoscope, tar geted abdominal pressure and regular patient position change are also important aids to successfully reaching the caecum. It is expected that the caecum should be r eached in at least 90% of  colonoscopies and is confirmed by the presence of  the appendiceal orifice, the triradiate fold, the ileocaecal valve and preferably terminal ileal intubation ( Figure 9.14 ). Historically , air was used to insu ffl ate the bowel, but carbon dioxide is now preferred owing to better patient tolerance and lower risk of  perforation. Recent evidence has suggested that using water alone to distend the colon ma y reduce patient dis - comfort further. The ability to take mucosal biopsies and resect polyps ensures that colonoscopy is the most appropriate investigation - for the majority of  patients. In selected groups, CT colonog raphy and colon capsule endoscopy provide an alternative route for investigating colonic pathology , though these are limited by the inability to acquire tissue. Accordingly , colonoscopy remains the cornerstone of  most colorectal cancer (CRC) screening programmes globally , whether it is used as the initial screen ing modality or following a faecal immunochemical test (FIT). Johann Conrad Peyer , 1653–1712, Professor of  Logic, Rhetoric and Medicine, Scha ff hausen, Switzerland, described the lymph follicles in the intestine in 1677. detected and hence decrease mortality , as well as to identify and remove adenomatous polyps prior to the development of  overt cancer. Higher adenoma detection rates (ADRs) are er rates of  interval cancers and, as such, associated with lo w the ADR is an important indicator of  colonoscopy quality . ADRs can be improved with measures such as a longer time taken on withdrawal from the caecum, optimal bowel prepa - ration, patient position changes and a ‘second look’ of  the right colon by changing patient position or by retroflexing the colonoscope. Distal attachments, such as a transparent cap or TM , can improve ADRs further. an Endocu ff Vision Summary box 9.7 Indications for colonoscopy /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF 

(b)
(c)
Figure 9.14
The caecal pole may not be easy to identify
therefore, the endoscopist should con
/f_i
rm complete colonoscopy by
visualising the appendix ori
/f_i
ce
(b)
(arrow) or preferably intubating the
terminal ileum
(c)
, which demonstrates villi and Peyer’s patches.
Rectal bleeding unexplained after proctoscopy/sigmoidoscopy
(see
Chapter 77
)
Abdominal pain related to bowel actions
Iron de
/f_i
ciency anaemia (combined with OGD)
Right iliac fossa mass if imaging suggestive of colonic origin
Unexplained alteration in bowel habit
Chronic diarrhoea (>6
/uni00A0
weeks) after sigmoidoscopy/rectal
biopsy and negative coeliac serology
Follow-up of CRC and polyps
Screening of patients with a family history of CRC
Assessment/removal of a lesion seen on radiological
examination
Assessment of ulcerative colitis/Crohn’s extent and activity
Surveillance of in
/f_l
ammatory bowel disease
Surveillance in patients with acromegaly or following
ureterosigmoidostomy

COLONSCOPY

- Early attempts at colonoscopy were hindered by poor technique and limitations of available instruments. The ability to steer an endoscope around the entire colon and into the terminal ileum was made possible by the development of  fully flexible colonoscopes with >90° angulation of  the tip. Advances in - bowel preparation have enhanced mucosal visualisation. Understanding two key technical aspects of  colonoscopy allows a greater caecal intubation rate and ileal intubation tic with minimal discomfort using light sedation. The first is that continued inward pressure of  the endoscope results in loop formation within the mobile sigmoid and transverse colon, which in turn leads to paradoxical movement and loss of  fine tip control. The second is that pulling back the scope regularly with appropriate torque to ensure a straight passage through the sigmoid colon and around the splenic flexure greatly aids the completion of  right-sided examination. Endoscopic navigation systems such as Scope Guide (Olympus) and Scope Pilot (Pentax) can help to characterise the nature of  the loop, allowing for more accurate loop reso - lution techniques. Increasing the sti ff ness of  the colonoscope, tar geted abdominal pressure and regular patient position change are also important aids to successfully reaching the caecum. It is expected that the caecum should be r eached in at least 90% of  colonoscopies and is confirmed by the presence of  the appendiceal orifice, the triradiate fold, the ileocaecal valve and preferably terminal ileal intubation ( Figure 9.14 ). Historically , air was used to insu ffl ate the bowel, but carbon dioxide is now preferred owing to better patient tolerance and lower risk of  perforation. Recent evidence has suggested that using water alone to distend the colon ma y reduce patient dis - comfort further. The ability to take mucosal biopsies and resect polyps ensures that colonoscopy is the most appropriate investigation - for the majority of  patients. In selected groups, CT colonog raphy and colon capsule endoscopy provide an alternative route for investigating colonic pathology , though these are limited by the inability to acquire tissue. Accordingly , colonoscopy remains the cornerstone of  most colorectal cancer (CRC) screening programmes globally , whether it is used as the initial screen ing modality or following a faecal immunochemical test (FIT). Johann Conrad Peyer , 1653–1712, Professor of  Logic, Rhetoric and Medicine, Scha ff hausen, Switzerland, described the lymph follicles in the intestine in 1677. detected and hence decrease mortality , as well as to identify and remove adenomatous polyps prior to the development of  overt cancer. Higher adenoma detection rates (ADRs) are er rates of  interval cancers and, as such, associated with lo w the ADR is an important indicator of  colonoscopy quality . ADRs can be improved with measures such as a longer time taken on withdrawal from the caecum, optimal bowel prepa - ration, patient position changes and a ‘second look’ of  the right colon by changing patient position or by retroflexing the colonoscope. Distal attachments, such as a transparent cap or TM , can improve ADRs further. an Endocu ff Vision Summary box 9.7 Indications for colonoscopy /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF 

(b)
(c)
Figure 9.14
The caecal pole may not be easy to identify
therefore, the endoscopist should con
/f_i
rm complete colonoscopy by
visualising the appendix ori
/f_i
ce
(b)
(arrow) or preferably intubating the
terminal ileum
(c)
, which demonstrates villi and Peyer’s patches.
Rectal bleeding unexplained after proctoscopy/sigmoidoscopy
(see
Chapter 77
)
Abdominal pain related to bowel actions
Iron de
/f_i
ciency anaemia (combined with OGD)
Right iliac fossa mass if imaging suggestive of colonic origin
Unexplained alteration in bowel habit
Chronic diarrhoea (>6
/uni00A0
weeks) after sigmoidoscopy/rectal
biopsy and negative coeliac serology
Follow-up of CRC and polyps
Screening of patients with a family history of CRC
Assessment/removal of a lesion seen on radiological
examination
Assessment of ulcerative colitis/Crohn’s extent and activity
Surveillance of in
/f_l
ammatory bowel disease
Surveillance in patients with acromegaly or following
ureterosigmoidostomy

COLONSCOPY

- Early attempts at colonoscopy were hindered by poor technique and limitations of available instruments. The ability to steer an endoscope around the entire colon and into the terminal ileum was made possible by the development of  fully flexible colonoscopes with >90° angulation of  the tip. Advances in - bowel preparation have enhanced mucosal visualisation. Understanding two key technical aspects of  colonoscopy allows a greater caecal intubation rate and ileal intubation tic with minimal discomfort using light sedation. The first is that continued inward pressure of  the endoscope results in loop formation within the mobile sigmoid and transverse colon, which in turn leads to paradoxical movement and loss of  fine tip control. The second is that pulling back the scope regularly with appropriate torque to ensure a straight passage through the sigmoid colon and around the splenic flexure greatly aids the completion of  right-sided examination. Endoscopic navigation systems such as Scope Guide (Olympus) and Scope Pilot (Pentax) can help to characterise the nature of  the loop, allowing for more accurate loop reso - lution techniques. Increasing the sti ff ness of  the colonoscope, tar geted abdominal pressure and regular patient position change are also important aids to successfully reaching the caecum. It is expected that the caecum should be r eached in at least 90% of  colonoscopies and is confirmed by the presence of  the appendiceal orifice, the triradiate fold, the ileocaecal valve and preferably terminal ileal intubation ( Figure 9.14 ). Historically , air was used to insu ffl ate the bowel, but carbon dioxide is now preferred owing to better patient tolerance and lower risk of  perforation. Recent evidence has suggested that using water alone to distend the colon ma y reduce patient dis - comfort further. The ability to take mucosal biopsies and resect polyps ensures that colonoscopy is the most appropriate investigation - for the majority of  patients. In selected groups, CT colonog raphy and colon capsule endoscopy provide an alternative route for investigating colonic pathology , though these are limited by the inability to acquire tissue. Accordingly , colonoscopy remains the cornerstone of  most colorectal cancer (CRC) screening programmes globally , whether it is used as the initial screen ing modality or following a faecal immunochemical test (FIT). Johann Conrad Peyer , 1653–1712, Professor of  Logic, Rhetoric and Medicine, Scha ff hausen, Switzerland, described the lymph follicles in the intestine in 1677. detected and hence decrease mortality , as well as to identify and remove adenomatous polyps prior to the development of  overt cancer. Higher adenoma detection rates (ADRs) are er rates of  interval cancers and, as such, associated with lo w the ADR is an important indicator of  colonoscopy quality . ADRs can be improved with measures such as a longer time taken on withdrawal from the caecum, optimal bowel prepa - ration, patient position changes and a ‘second look’ of  the right colon by changing patient position or by retroflexing the colonoscope. Distal attachments, such as a transparent cap or TM , can improve ADRs further. an Endocu ff Vision Summary box 9.7 Indications for colonoscopy /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF 

(b)
(c)
Figure 9.14
The caecal pole may not be easy to identify
therefore, the endoscopist should con
/f_i
rm complete colonoscopy by
visualising the appendix ori
/f_i
ce
(b)
(arrow) or preferably intubating the
terminal ileum
(c)
, which demonstrates villi and Peyer’s patches.
Rectal bleeding unexplained after proctoscopy/sigmoidoscopy
(see
Chapter 77
)
Abdominal pain related to bowel actions
Iron de
/f_i
ciency anaemia (combined with OGD)
Right iliac fossa mass if imaging suggestive of colonic origin
Unexplained alteration in bowel habit
Chronic diarrhoea (>6
/uni00A0
weeks) after sigmoidoscopy/rectal
biopsy and negative coeliac serology
Follow-up of CRC and polyps
Screening of patients with a family history of CRC
Assessment/removal of a lesion seen on radiological
examination
Assessment of ulcerative colitis/Crohn’s extent and activity
Surveillance of in
/f_l
ammatory bowel disease
Surveillance in patients with acromegaly or following
ureterosigmoidostomy

# CONCLUSIONS

CONCLUSIONS

Over the last 30 years endoscopy has become an integral part of  the diagnostic work-up of  patients with gastrointestinal disease. Whereas advances in radiology and capsule studies may obviate the need for some diagnostic procedures, the ability to take mucosal biopsies will ensure that it retains a vital role. Ongoing developments in technology such as magnifying endoscopy and chromoendoscopy give near-histological qual ity definition and there is considerable interest in the role of artificial intelligence to augment near-patient diagnosis. There have also been major advances in the range of  conditions that are amenable to endoscopic therapy; such therapy may have substantially lo wer associated morbidity rates than traditional surgical approaches. However, as the scope of  procedures widens and the age range/comorbidities of  the patients increases, it is beholden on the endoscopist to ensure that he or she adheres to appropriate governance/consent and sedation practice to minimise complications. Allison MC, Sandoe JAT , Tighe R et al . Antibiotic prophylaxis in gastrointestinal endoscopy . Gut 2009; 58 : 869–80. Everett SM, Gri ffi ths H, Nandasoma U et al , Guideline for obtaining valid consent for gastrointestinal endoscopy procedures Gut 2016; 65 (10): 1585–601. Ferlitsch M, Moss A, Hassan C et al . Colorectal polypectomy and en - doscopic mucosal resection (EMR): European Society of  Gastroin - testinal Endoscopy (ESGE) Clinical Guideline. Endoscopy 2017; 49 : 270–97. Hawes RH, Fockens P , Varadarajulu S. Endosonography , 3rd edn. Phila - delphia: Saunders, 2014. Haycock A, Cohen J, Saunders BP et al. Cotton and Williams’ practical gastrointestinal endoscopy, 7th edn. Oxford: Wiley-Blackwell, 2014. Members of  the British Society of  Gastroenterology Endoscopy Sec - tion Committee Working Party on Decontamination of  Equipment for Gastrointestinal Endoscopy . BSG guidance for decontamination of equipment for gastrointestinal endoscopy , 2020. Available from https:// www .bsg.org.uk/wp-content/uploads/2021/02/BSG-Decontami - nation-guidance-2020-update.pdf Rees CJ, Thomas Gibson S, Rutter MD et al . UK key performance in - dicators and quality assurance standards for colonoscopy . Gut 2016; 65 : 1923–29. Rutter MD, East J, Rees CJ, et al . British Society of  Gastroenterology/ Association of  Coloproctology of  Great Britain and Ireland/Public Health England post-polypectomy and post-colorectal cancer re - section surveillance guidelines. Gut 2020; 69 : 201–23. - V eitch AM, Radaelli F , Alikhan R et al . Endoscopy in patients on an - tiplatelet or anticoagulant therapy: British Society of  Gastroenter - ology (BSG) and European Society of  Gastrointestinal Endoscopy (ESGE) guideline update. Gut 2021; 70 : 1611–1628. CONCLUSIONS

Over the last 30 years endoscopy has become an integral part of  the diagnostic work-up of  patients with gastrointestinal disease. Whereas advances in radiology and capsule studies may obviate the need for some diagnostic procedures, the ability to take mucosal biopsies will ensure that it retains a vital role. Ongoing developments in technology such as magnifying endoscopy and chromoendoscopy give near-histological qual ity definition and there is considerable interest in the role of artificial intelligence to augment near-patient diagnosis. There have also been major advances in the range of  conditions that are amenable to endoscopic therapy; such therapy may have substantially lo wer associated morbidity rates than traditional surgical approaches. However, as the scope of  procedures widens and the age range/comorbidities of  the patients increases, it is beholden on the endoscopist to ensure that he or she adheres to appropriate governance/consent and sedation practice to minimise complications. Allison MC, Sandoe JAT , Tighe R et al . Antibiotic prophylaxis in gastrointestinal endoscopy . Gut 2009; 58 : 869–80. Everett SM, Gri ffi ths H, Nandasoma U et al , Guideline for obtaining valid consent for gastrointestinal endoscopy procedures Gut 2016; 65 (10): 1585–601. Ferlitsch M, Moss A, Hassan C et al . Colorectal polypectomy and en - doscopic mucosal resection (EMR): European Society of  Gastroin - testinal Endoscopy (ESGE) Clinical Guideline. Endoscopy 2017; 49 : 270–97. Hawes RH, Fockens P , Varadarajulu S. Endosonography , 3rd edn. Phila - delphia: Saunders, 2014. Haycock A, Cohen J, Saunders BP et al. Cotton and Williams’ practical gastrointestinal endoscopy, 7th edn. Oxford: Wiley-Blackwell, 2014. Members of  the British Society of  Gastroenterology Endoscopy Sec - tion Committee Working Party on Decontamination of  Equipment for Gastrointestinal Endoscopy . BSG guidance for decontamination of equipment for gastrointestinal endoscopy , 2020. Available from https:// www .bsg.org.uk/wp-content/uploads/2021/02/BSG-Decontami - nation-guidance-2020-update.pdf Rees CJ, Thomas Gibson S, Rutter MD et al . UK key performance in - dicators and quality assurance standards for colonoscopy . Gut 2016; 65 : 1923–29. Rutter MD, East J, Rees CJ, et al . British Society of  Gastroenterology/ Association of  Coloproctology of  Great Britain and Ireland/Public Health England post-polypectomy and post-colorectal cancer re - section surveillance guidelines. Gut 2020; 69 : 201–23. - V eitch AM, Radaelli F , Alikhan R et al . Endoscopy in patients on an - tiplatelet or anticoagulant therapy: British Society of  Gastroenter - ology (BSG) and European Society of  Gastrointestinal Endoscopy (ESGE) guideline update. Gut 2021; 70 : 1611–1628. CONCLUSIONS

Over the last 30 years endoscopy has become an integral part of  the diagnostic work-up of  patients with gastrointestinal disease. Whereas advances in radiology and capsule studies may obviate the need for some diagnostic procedures, the ability to take mucosal biopsies will ensure that it retains a vital role. Ongoing developments in technology such as magnifying endoscopy and chromoendoscopy give near-histological qual ity definition and there is considerable interest in the role of artificial intelligence to augment near-patient diagnosis. There have also been major advances in the range of  conditions that are amenable to endoscopic therapy; such therapy may have substantially lo wer associated morbidity rates than traditional surgical approaches. However, as the scope of  procedures widens and the age range/comorbidities of  the patients increases, it is beholden on the endoscopist to ensure that he or she adheres to appropriate governance/consent and sedation practice to minimise complications. Allison MC, Sandoe JAT , Tighe R et al . Antibiotic prophylaxis in gastrointestinal endoscopy . Gut 2009; 58 : 869–80. Everett SM, Gri ffi ths H, Nandasoma U et al , Guideline for obtaining valid consent for gastrointestinal endoscopy procedures Gut 2016; 65 (10): 1585–601. Ferlitsch M, Moss A, Hassan C et al . Colorectal polypectomy and en - doscopic mucosal resection (EMR): European Society of  Gastroin - testinal Endoscopy (ESGE) Clinical Guideline. Endoscopy 2017; 49 : 270–97. Hawes RH, Fockens P , Varadarajulu S. Endosonography , 3rd edn. Phila - delphia: Saunders, 2014. Haycock A, Cohen J, Saunders BP et al. Cotton and Williams’ practical gastrointestinal endoscopy, 7th edn. Oxford: Wiley-Blackwell, 2014. Members of  the British Society of  Gastroenterology Endoscopy Sec - tion Committee Working Party on Decontamination of  Equipment for Gastrointestinal Endoscopy . BSG guidance for decontamination of equipment for gastrointestinal endoscopy , 2020. Available from https:// www .bsg.org.uk/wp-content/uploads/2021/02/BSG-Decontami - nation-guidance-2020-update.pdf Rees CJ, Thomas Gibson S, Rutter MD et al . UK key performance in - dicators and quality assurance standards for colonoscopy . Gut 2016; 65 : 1923–29. Rutter MD, East J, Rees CJ, et al . British Society of  Gastroenterology/ Association of  Coloproctology of  Great Britain and Ireland/Public Health England post-polypectomy and post-colorectal cancer re - section surveillance guidelines. Gut 2020; 69 : 201–23. - V eitch AM, Radaelli F , Alikhan R et al . Endoscopy in patients on an - tiplatelet or anticoagulant therapy: British Society of  Gastroenter - ology (BSG) and European Society of  Gastrointestinal Endoscopy (ESGE) guideline update. Gut 2021; 70 : 1611–1628.

# CONSENT IN ENDOSCOPY

CONSENT IN ENDOSCOPY

Approximately 1% of  medical negligence claims in the USA relate to the practice of  endoscopy . Many of  these could have been avoided by a careful explanation of  the procedure, including an honest discussion of  the risks and benefits. Therefore, obtaining informed consent is a cornerstone of good endoscopic practice. It preserves a patient’s autonomy , facilitates communication and acts as a shield against future complaints and claims of  malpractice. The most important aspect of  the consent procedure is that a patient understands the nature, purpose and risk of  a partic - ular procedure, in addition to potential alternatives. Current guidelines w ould suggest that a patient should be informed of minor adverse events with a risk of  more than 10% and serious events with an incidence of  more than 0.5%. The ke y risks . British of  endoscopy are summarised in Summary box 9.2 Society of  Gastroenterology Guidelines for Consent have been published (see Further reading). - Summary box 9.2 The risks of endoscopy /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF - 

Sedation-related cardiorespiratory complications
Damage to dentition
Aspiration
Perforation or haemorrhage after endoscopic dilatation/
therapeutic EUS
Perforation, infection and aspiration after percutaneous
endoscopic gastrostomy insertion
Perforation or haemorrhage after
/f_l
exible sigmoidoscopy/
colonoscopy with polypectomy
Pancreatitis, cholangitis, perforation or bleeding after
endoscopic retrograde cholangiopancreatography

CONSENT IN ENDOSCOPY

Approximately 1% of  medical negligence claims in the USA relate to the practice of  endoscopy . Many of  these could have been avoided by a careful explanation of  the procedure, including an honest discussion of  the risks and benefits. Therefore, obtaining informed consent is a cornerstone of good endoscopic practice. It preserves a patient’s autonomy , facilitates communication and acts as a shield against future complaints and claims of  malpractice. The most important aspect of  the consent procedure is that a patient understands the nature, purpose and risk of  a partic - ular procedure, in addition to potential alternatives. Current guidelines w ould suggest that a patient should be informed of minor adverse events with a risk of  more than 10% and serious events with an incidence of  more than 0.5%. The ke y risks . British of  endoscopy are summarised in Summary box 9.2 Society of  Gastroenterology Guidelines for Consent have been published (see Further reading). - Summary box 9.2 The risks of endoscopy /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF - 

Sedation-related cardiorespiratory complications
Damage to dentition
Aspiration
Perforation or haemorrhage after endoscopic dilatation/
therapeutic EUS
Perforation, infection and aspiration after percutaneous
endoscopic gastrostomy insertion
Perforation or haemorrhage after
/f_l
exible sigmoidoscopy/
colonoscopy with polypectomy
Pancreatitis, cholangitis, perforation or bleeding after
endoscopic retrograde cholangiopancreatography

CONSENT IN ENDOSCOPY

Approximately 1% of  medical negligence claims in the USA relate to the practice of  endoscopy . Many of  these could have been avoided by a careful explanation of  the procedure, including an honest discussion of  the risks and benefits. Therefore, obtaining informed consent is a cornerstone of good endoscopic practice. It preserves a patient’s autonomy , facilitates communication and acts as a shield against future complaints and claims of  malpractice. The most important aspect of  the consent procedure is that a patient understands the nature, purpose and risk of  a partic - ular procedure, in addition to potential alternatives. Current guidelines w ould suggest that a patient should be informed of minor adverse events with a risk of  more than 10% and serious events with an incidence of  more than 0.5%. The ke y risks . British of  endoscopy are summarised in Summary box 9.2 Society of  Gastroenterology Guidelines for Consent have been published (see Further reading). - Summary box 9.2 The risks of endoscopy /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF - 

Sedation-related cardiorespiratory complications
Damage to dentition
Aspiration
Perforation or haemorrhage after endoscopic dilatation/
therapeutic EUS
Perforation, infection and aspiration after percutaneous
endoscopic gastrostomy insertion
Perforation or haemorrhage after
/f_l
exible sigmoidoscopy/
colonoscopy with polypectomy
Pancreatitis, cholangitis, perforation or bleeding after
endoscopic retrograde cholangiopancreatography

# Capsule endoscopy

Capsule endoscopy

The prototype capsule endoscope was developed at the Royal London Hospital in the UK by Professor Paul Swain. Several companies have developed di ff erent systems for routine clinical use, but the basic principles remain identical. The  technique requires three main components: an ingestible capsule, a portable data recorder and a workstation equipped with image-processing software. The capsule consists of an optical dome and lens, two light-emitting diodes, a processor, a battery , a transmitter, and an antenna encased in a resistant coat the size of a large vitamin pill ( Figure 9.11 ). It acquires video images during natural propulsion through the digestive system that it transmits via a digital radiofrequency communication channel to the recorder unit worn outside the body; this also contains sensors that allow basic localisation of  the site of image capture within the abdomen. Upon completion of  the Christopher Paul Swain , b. 1943, gastroenterologist, The Royal London Hospital, London, UK. Burrill Bernard Crohn , 1884–1983, gastroenterologist, Mount Sinai Hospital, New Y ork, NY , USA, described regional ileitis in 1932. - - - - examination, the physician transfers the accumulated data to the workstation for interpretation via a high-capacity digital link. The workstation is a modified personal computer required ms of for o ff -line data storage, interpretation and analysis of the acquired images and report generation. The small bowel capsule provides good visualisation from mouth to colon with a high diagnostic yield. It compares - favourably with other techniques for localisation of  occult gastrointestinal bleeding and the diagnosis of  small bowel Crohn’s disease. Use of the capsule endoscope is contra - indicated in patients with known small bowel strictures in which le - it may impact, resulting in acute obstruction and requiring retrieval at laparotomy or via laparoscopy . Se vere gastroparesis and pseudo-obstruction are also relative contraindications to its use. Some units advocate a barium follow-through or small bowel MRI to exclude stricturing disease in all patients before capsule endoscopy . However, there are well-reported episodes of  capsule impaction in a stricture that was not visualised on prior imaging. Therefore, a ‘dummy’ patency capsule that can be tracked via a handheld device or conventional radiology as it passes through the intestine should be used in all patients in whom there is a possibility of  stricturing disease. The patency capsule will dissolve after 40 hours if  it becomes impacted. Technology in this field is rapidly advancing, with capsule sys - tems now available to image the colon. 

disadvantages of the currently available modalities to
endoscope the small intestine.
Technique Advantages
Disadvantages
Some discomfort
Conventional
Simple technique with
Can only access
enteroscopy
wide availability
proximal small bowel
Full range of
therapeutics available
Performed under
sedation
No biopsies
Capsule
Able to visualise the
Not controllable and no
endoscopy
entire small bowel
accurate localisation
Preferable for patients
Variable transit
No sedation
Incomplete studies
Painless
owing to battery life
Not suitable for patients
with strictures
Large capsule to swallow
Requires admission
Able to visualise the
Double-/
Specialist centres only
entire small bowel
single-balloon
Complications include
Full range of
enteroscopy
perforation
therapeutics

Capsule endoscopy

The prototype capsule endoscope was developed at the Royal London Hospital in the UK by Professor Paul Swain. Several companies have developed di ff erent systems for routine clinical use, but the basic principles remain identical. The  technique requires three main components: an ingestible capsule, a portable data recorder and a workstation equipped with image-processing software. The capsule consists of an optical dome and lens, two light-emitting diodes, a processor, a battery , a transmitter, and an antenna encased in a resistant coat the size of a large vitamin pill ( Figure 9.11 ). It acquires video images during natural propulsion through the digestive system that it transmits via a digital radiofrequency communication channel to the recorder unit worn outside the body; this also contains sensors that allow basic localisation of  the site of image capture within the abdomen. Upon completion of  the Christopher Paul Swain , b. 1943, gastroenterologist, The Royal London Hospital, London, UK. Burrill Bernard Crohn , 1884–1983, gastroenterologist, Mount Sinai Hospital, New Y ork, NY , USA, described regional ileitis in 1932. - - - - examination, the physician transfers the accumulated data to the workstation for interpretation via a high-capacity digital link. The workstation is a modified personal computer required ms of for o ff -line data storage, interpretation and analysis of the acquired images and report generation. The small bowel capsule provides good visualisation from mouth to colon with a high diagnostic yield. It compares - favourably with other techniques for localisation of  occult gastrointestinal bleeding and the diagnosis of  small bowel Crohn’s disease. Use of the capsule endoscope is contra - indicated in patients with known small bowel strictures in which le - it may impact, resulting in acute obstruction and requiring retrieval at laparotomy or via laparoscopy . Se vere gastroparesis and pseudo-obstruction are also relative contraindications to its use. Some units advocate a barium follow-through or small bowel MRI to exclude stricturing disease in all patients before capsule endoscopy . However, there are well-reported episodes of  capsule impaction in a stricture that was not visualised on prior imaging. Therefore, a ‘dummy’ patency capsule that can be tracked via a handheld device or conventional radiology as it passes through the intestine should be used in all patients in whom there is a possibility of  stricturing disease. The patency capsule will dissolve after 40 hours if  it becomes impacted. Technology in this field is rapidly advancing, with capsule sys - tems now available to image the colon. 

disadvantages of the currently available modalities to
endoscope the small intestine.
Technique Advantages
Disadvantages
Some discomfort
Conventional
Simple technique with
Can only access
enteroscopy
wide availability
proximal small bowel
Full range of
therapeutics available
Performed under
sedation
No biopsies
Capsule
Able to visualise the
Not controllable and no
endoscopy
entire small bowel
accurate localisation
Preferable for patients
Variable transit
No sedation
Incomplete studies
Painless
owing to battery life
Not suitable for patients
with strictures
Large capsule to swallow
Requires admission
Able to visualise the
Double-/
Specialist centres only
entire small bowel
single-balloon
Complications include
Full range of
enteroscopy
perforation
therapeutics

Capsule endoscopy

The prototype capsule endoscope was developed at the Royal London Hospital in the UK by Professor Paul Swain. Several companies have developed di ff erent systems for routine clinical use, but the basic principles remain identical. The  technique requires three main components: an ingestible capsule, a portable data recorder and a workstation equipped with image-processing software. The capsule consists of an optical dome and lens, two light-emitting diodes, a processor, a battery , a transmitter, and an antenna encased in a resistant coat the size of a large vitamin pill ( Figure 9.11 ). It acquires video images during natural propulsion through the digestive system that it transmits via a digital radiofrequency communication channel to the recorder unit worn outside the body; this also contains sensors that allow basic localisation of  the site of image capture within the abdomen. Upon completion of  the Christopher Paul Swain , b. 1943, gastroenterologist, The Royal London Hospital, London, UK. Burrill Bernard Crohn , 1884–1983, gastroenterologist, Mount Sinai Hospital, New Y ork, NY , USA, described regional ileitis in 1932. - - - - examination, the physician transfers the accumulated data to the workstation for interpretation via a high-capacity digital link. The workstation is a modified personal computer required ms of for o ff -line data storage, interpretation and analysis of the acquired images and report generation. The small bowel capsule provides good visualisation from mouth to colon with a high diagnostic yield. It compares - favourably with other techniques for localisation of  occult gastrointestinal bleeding and the diagnosis of  small bowel Crohn’s disease. Use of the capsule endoscope is contra - indicated in patients with known small bowel strictures in which le - it may impact, resulting in acute obstruction and requiring retrieval at laparotomy or via laparoscopy . Se vere gastroparesis and pseudo-obstruction are also relative contraindications to its use. Some units advocate a barium follow-through or small bowel MRI to exclude stricturing disease in all patients before capsule endoscopy . However, there are well-reported episodes of  capsule impaction in a stricture that was not visualised on prior imaging. Therefore, a ‘dummy’ patency capsule that can be tracked via a handheld device or conventional radiology as it passes through the intestine should be used in all patients in whom there is a possibility of  stricturing disease. The patency capsule will dissolve after 40 hours if  it becomes impacted. Technology in this field is rapidly advancing, with capsule sys - tems now available to image the colon. 

disadvantages of the currently available modalities to
endoscope the small intestine.
Technique Advantages
Disadvantages
Some discomfort
Conventional
Simple technique with
Can only access
enteroscopy
wide availability
proximal small bowel
Full range of
therapeutics available
Performed under
sedation
No biopsies
Capsule
Able to visualise the
Not controllable and no
endoscopy
entire small bowel
accurate localisation
Preferable for patients
Variable transit
No sedation
Incomplete studies
Painless
owing to battery life
Not suitable for patients
with strictures
Large capsule to swallow
Requires admission
Able to visualise the
Double-/
Specialist centres only
entire small bowel
single-balloon
Complications include
Full range of
enteroscopy
perforation
therapeutics

# Complications associated with endoscopic retrograd

Complications associated with endoscopic retrograde cholangiopancreatography

The same risks associated with other endoscopic procedures also apply to patients undergoing ERCP , but risks may be increased because of  the increased patient frailty and high sedation levels required. Complications specific to ERCP include duodenal perforation (1.3%), haemorrhage (1.4%) after sphincterotomy , pancreatitis (4.3%) and sepsis (3–30%); the mortality rate approaches 1%. It is important to remember that postsphincterotomy complications may be retroperitoneal and CT scanning should be performed in patients with pain, tachycardia or hypotension post procedure. Although normally mild, post-ERCP pancreatitis can be severe with extensive pancreatic necrosis and is associated with a significant mortality rate ( Table 9.5 ). Where there is no contraindication, patients under going ERCP should receive per-rectal indometacin or diclofenac immediately before or after the procedure to reduce the risk of  post-ERCP pancre atitis. Ruggero Oddi , 1866–1913, anatomist and physiologist, Perugia, Italy , wrote about the structure and function of  the ampullary sphincter in 1887, when still a student. He struggled in later life with drug addiction. - - - - 

De
/f_i
nite
Suspected SOD
Young age
Normal bilirubin
Prior ERCP-related pancreatitis
Dif
/f_i
cult cannulation
Pancreatic duct contrast injection
Pancreatic sphincterotomy
Balloon dilatation of biliary sphincter
Possible
Female sex
Low volume of ERCPs performed
Absent CBD stone
CBD, common bile duct; ERCP , endoscopic retrograde cholangio
-
pancreatography; SOD, sphincter of Oddi dysfunction.

Complications associated with endoscopic retrograde cholangiopancreatography

The same risks associated with other endoscopic procedures also apply to patients undergoing ERCP , but risks may be increased because of  the increased patient frailty and high sedation levels required. Complications specific to ERCP include duodenal perforation (1.3%), haemorrhage (1.4%) after sphincterotomy , pancreatitis (4.3%) and sepsis (3–30%); the mortality rate approaches 1%. It is important to remember that postsphincterotomy complications may be retroperitoneal and CT scanning should be performed in patients with pain, tachycardia or hypotension post procedure. Although normally mild, post-ERCP pancreatitis can be severe with extensive pancreatic necrosis and is associated with a significant mortality rate ( Table 9.5 ). Where there is no contraindication, patients under going ERCP should receive per-rectal indometacin or diclofenac immediately before or after the procedure to reduce the risk of  post-ERCP pancre atitis. Ruggero Oddi , 1866–1913, anatomist and physiologist, Perugia, Italy , wrote about the structure and function of  the ampullary sphincter in 1887, when still a student. He struggled in later life with drug addiction. - - - - 

De
/f_i
nite
Suspected SOD
Young age
Normal bilirubin
Prior ERCP-related pancreatitis
Dif
/f_i
cult cannulation
Pancreatic duct contrast injection
Pancreatic sphincterotomy
Balloon dilatation of biliary sphincter
Possible
Female sex
Low volume of ERCPs performed
Absent CBD stone
CBD, common bile duct; ERCP , endoscopic retrograde cholangio
-
pancreatography; SOD, sphincter of Oddi dysfunction.

# Complications associated with endoscopic retrograde cholangiopancreatography

Complications associated with endoscopic retrograde cholangiopancreatography

The same risks associated with other endoscopic procedures also apply to patients undergoing ERCP , but risks may be increased because of  the increased patient frailty and high sedation levels required. Complications specific to ERCP include duodenal perforation (1.3%), haemorrhage (1.4%) after sphincterotomy , pancreatitis (4.3%) and sepsis (3–30%); the mortality rate approaches 1%. It is important to remember that postsphincterotomy complications may be retroperitoneal and CT scanning should be performed in patients with pain, tachycardia or hypotension post procedure. Although normally mild, post-ERCP pancreatitis can be severe with extensive pancreatic necrosis and is associated with a significant mortality rate ( Table 9.5 ). Where there is no contraindication, patients under going ERCP should receive per-rectal indometacin or diclofenac immediately before or after the procedure to reduce the risk of  post-ERCP pancre atitis. Ruggero Oddi , 1866–1913, anatomist and physiologist, Perugia, Italy , wrote about the structure and function of  the ampullary sphincter in 1887, when still a student. He struggled in later life with drug addiction. - - - - 

De
/f_i
nite
Suspected SOD
Young age
Normal bilirubin
Prior ERCP-related pancreatitis
Dif
/f_i
cult cannulation
Pancreatic duct contrast injection
Pancreatic sphincterotomy
Balloon dilatation of biliary sphincter
Possible
Female sex
Low volume of ERCPs performed
Absent CBD stone
CBD, common bile duct; ERCP , endoscopic retrograde cholangio
-
pancreatography; SOD, sphincter of Oddi dysfunction.

# Complications of colonoscopy

Complications of colonoscopy

Complications during routine diagnostic colonoscopy are rare when performed by an experienced endoscopist. Extensive diverticulosis, diverticulitis and severe colitis are risk factors for perforation during colonoscopy . In the case of  colitis, an unpre - pared flexible sigmoidoscopy is usually su ffi cient for diagnostic purposes. Polypectomy is associated with an increased rate of  perforation (0.1%) and haemorrhage (0.3%). Immediate haemorrhage can be managed with endoclips or snare-tip coagulation. Delayed haemorrhage may occur 1–14 days post polypectomy and can normally be managed by conservative observation. Transfusion may occasionally be required, and a repeat colonoscopy may be necessary . If  recognised at the time of  polypectomy , small perforations should be closed using endoclips and the patient may need a period of  observation. Symptoms of  abdominal pain and cardiovascular compromise after a polypectomy raise the possibility of  a delayed perforation and faecal contamination. Patients should be kept nil by mouth and receive intravenous resuscitation and antibiotics. Prompt assessment with a CT scan will often distinguish between a frank perforation and a transmural burn with associated local ised peritonitis (the postpolypectomy syndrome). Assessment by an experienced colorectal surgeon is essential, as surgery is often the most appropriate course of  action. One disadvantage of conventional endoscopy is that exam - ination is limited to the mucosal surface, and it is not possible to diagnose submucosal or extraintestinal pathology . These limitations can be overcome using EUS, which combines the traditional mucosal image with a separate ultrasound ly depicts the intestinal layers and proximate view that clear extraintestinal structures. Its use has revolutionised the staging and management of  upper gastrointestinal and hepatobiliary malignancy . There are two main types of  echoendoscope: the radial echoendoscope has a radially arranged ultrasound probe and a forward-viewing lens. This is used for diagnostic work such as local tumour staging in the oesophagus and stomach. The linear is a side-viewing scope with a working channel echoendoscope much like an ERCP scope, and a linearly arranged ultra - sound probe. This conformation allows ultrasound assessment and ultrasound-guided sampling of  tissues to be performed ( Figures 9.20 and 9.21 ) . Sampling of  paraoesophageal and coeliac lymph nodes and pancreatic, biliary and other solid abdominal lesions as well as drainage of  peripancreatic abscess ™ it can be performed. Using TTS Cystotomes or pseudocysts is possible to perform EUS cystgastrostomy and stent place - ment, and increasingly biliary interventional procedures are being performed with EUS assistance. EUS requires dedicated training, in both scope manipu - pretation. Owing to the width lation and radiographic inter and lack of  flexibility of  the endo-ultrasound scope as well as the duration of  complex therapeutic procedures, sedation is normally required, and some units perform tests using propofol-based anaesthesia. The main indications for EUS are . All patients undergoing therapeutic EUS listed in Table 9.6 require a normal coagulation screen. Complications include - oversedation and oesophageal perforation during diagnostic procedures and haemorrhage/perforation during therapeutic procedures. 

Figure 9.19
Malignant colonic obstruction can be palliated or tem
porarily relieved by insertion of a self-expanding metal stent (arrow).
‘Ragged’ edge suggesting invasion of adventitia
Tumour
Muscularis propria
Figure 9.20
Endoscopic ultrasound image of an oesophageal tumour
invading into the wall.
-
Figure 9.21
Endoscopic ultrasound (EUS)-guided
/f_i
ne-needle aspira
-
tion of a pancreatic head mass. CBD, common bile duct.



Diagnostic
Staging of oesophageal/gastric malignancy
Staging of hepatobiliary malignancy
Diagnosis of choledochal microlithiasis
Therapeutic
Biopsy of paraoesophageal lymph nodes
Biopsy of submucosal upper gastrointestinal
lesions
Biopsy of pancreaticobiliary mass
Biopsy of portal lymphadenopathy
Biopsy of left adrenal and left liver masses
Transgastric drainage of pancreatic pseudocyst
Coeliac plexus block

Complications of colonoscopy

Complications during routine diagnostic colonoscopy are rare when performed by an experienced endoscopist. Extensive diverticulosis, diverticulitis and severe colitis are risk factors for perforation during colonoscopy . In the case of  colitis, an unpre - pared flexible sigmoidoscopy is usually su ffi cient for diagnostic purposes. Polypectomy is associated with an increased rate of  perforation (0.1%) and haemorrhage (0.3%). Immediate haemorrhage can be managed with endoclips or snare-tip coagulation. Delayed haemorrhage may occur 1–14 days post polypectomy and can normally be managed by conservative observation. Transfusion may occasionally be required, and a repeat colonoscopy may be necessary . If  recognised at the time of  polypectomy , small perforations should be closed using endoclips and the patient may need a period of  observation. Symptoms of  abdominal pain and cardiovascular compromise after a polypectomy raise the possibility of  a delayed perforation and faecal contamination. Patients should be kept nil by mouth and receive intravenous resuscitation and antibiotics. Prompt assessment with a CT scan will often distinguish between a frank perforation and a transmural burn with associated local ised peritonitis (the postpolypectomy syndrome). Assessment by an experienced colorectal surgeon is essential, as surgery is often the most appropriate course of  action. One disadvantage of conventional endoscopy is that exam - ination is limited to the mucosal surface, and it is not possible to diagnose submucosal or extraintestinal pathology . These limitations can be overcome using EUS, which combines the traditional mucosal image with a separate ultrasound ly depicts the intestinal layers and proximate view that clear extraintestinal structures. Its use has revolutionised the staging and management of  upper gastrointestinal and hepatobiliary malignancy . There are two main types of  echoendoscope: the radial echoendoscope has a radially arranged ultrasound probe and a forward-viewing lens. This is used for diagnostic work such as local tumour staging in the oesophagus and stomach. The linear is a side-viewing scope with a working channel echoendoscope much like an ERCP scope, and a linearly arranged ultra - sound probe. This conformation allows ultrasound assessment and ultrasound-guided sampling of  tissues to be performed ( Figures 9.20 and 9.21 ) . Sampling of  paraoesophageal and coeliac lymph nodes and pancreatic, biliary and other solid abdominal lesions as well as drainage of  peripancreatic abscess ™ it can be performed. Using TTS Cystotomes or pseudocysts is possible to perform EUS cystgastrostomy and stent place - ment, and increasingly biliary interventional procedures are being performed with EUS assistance. EUS requires dedicated training, in both scope manipu - pretation. Owing to the width lation and radiographic inter and lack of  flexibility of  the endo-ultrasound scope as well as the duration of  complex therapeutic procedures, sedation is normally required, and some units perform tests using propofol-based anaesthesia. The main indications for EUS are . All patients undergoing therapeutic EUS listed in Table 9.6 require a normal coagulation screen. Complications include - oversedation and oesophageal perforation during diagnostic procedures and haemorrhage/perforation during therapeutic procedures. 

Figure 9.19
Malignant colonic obstruction can be palliated or tem
porarily relieved by insertion of a self-expanding metal stent (arrow).
‘Ragged’ edge suggesting invasion of adventitia
Tumour
Muscularis propria
Figure 9.20
Endoscopic ultrasound image of an oesophageal tumour
invading into the wall.
-
Figure 9.21
Endoscopic ultrasound (EUS)-guided
/f_i
ne-needle aspira
-
tion of a pancreatic head mass. CBD, common bile duct.



Diagnostic
Staging of oesophageal/gastric malignancy
Staging of hepatobiliary malignancy
Diagnosis of choledochal microlithiasis
Therapeutic
Biopsy of paraoesophageal lymph nodes
Biopsy of submucosal upper gastrointestinal
lesions
Biopsy of pancreaticobiliary mass
Biopsy of portal lymphadenopathy
Biopsy of left adrenal and left liver masses
Transgastric drainage of pancreatic pseudocyst
Coeliac plexus block

Complications of colonoscopy

Complications during routine diagnostic colonoscopy are rare when performed by an experienced endoscopist. Extensive diverticulosis, diverticulitis and severe colitis are risk factors for perforation during colonoscopy . In the case of  colitis, an unpre - pared flexible sigmoidoscopy is usually su ffi cient for diagnostic purposes. Polypectomy is associated with an increased rate of  perforation (0.1%) and haemorrhage (0.3%). Immediate haemorrhage can be managed with endoclips or snare-tip coagulation. Delayed haemorrhage may occur 1–14 days post polypectomy and can normally be managed by conservative observation. Transfusion may occasionally be required, and a repeat colonoscopy may be necessary . If  recognised at the time of  polypectomy , small perforations should be closed using endoclips and the patient may need a period of  observation. Symptoms of  abdominal pain and cardiovascular compromise after a polypectomy raise the possibility of  a delayed perforation and faecal contamination. Patients should be kept nil by mouth and receive intravenous resuscitation and antibiotics. Prompt assessment with a CT scan will often distinguish between a frank perforation and a transmural burn with associated local ised peritonitis (the postpolypectomy syndrome). Assessment by an experienced colorectal surgeon is essential, as surgery is often the most appropriate course of  action. One disadvantage of conventional endoscopy is that exam - ination is limited to the mucosal surface, and it is not possible to diagnose submucosal or extraintestinal pathology . These limitations can be overcome using EUS, which combines the traditional mucosal image with a separate ultrasound ly depicts the intestinal layers and proximate view that clear extraintestinal structures. Its use has revolutionised the staging and management of  upper gastrointestinal and hepatobiliary malignancy . There are two main types of  echoendoscope: the radial echoendoscope has a radially arranged ultrasound probe and a forward-viewing lens. This is used for diagnostic work such as local tumour staging in the oesophagus and stomach. The linear is a side-viewing scope with a working channel echoendoscope much like an ERCP scope, and a linearly arranged ultra - sound probe. This conformation allows ultrasound assessment and ultrasound-guided sampling of  tissues to be performed ( Figures 9.20 and 9.21 ) . Sampling of  paraoesophageal and coeliac lymph nodes and pancreatic, biliary and other solid abdominal lesions as well as drainage of  peripancreatic abscess ™ it can be performed. Using TTS Cystotomes or pseudocysts is possible to perform EUS cystgastrostomy and stent place - ment, and increasingly biliary interventional procedures are being performed with EUS assistance. EUS requires dedicated training, in both scope manipu - pretation. Owing to the width lation and radiographic inter and lack of  flexibility of  the endo-ultrasound scope as well as the duration of  complex therapeutic procedures, sedation is normally required, and some units perform tests using propofol-based anaesthesia. The main indications for EUS are . All patients undergoing therapeutic EUS listed in Table 9.6 require a normal coagulation screen. Complications include - oversedation and oesophageal perforation during diagnostic procedures and haemorrhage/perforation during therapeutic procedures. 

Figure 9.19
Malignant colonic obstruction can be palliated or tem
porarily relieved by insertion of a self-expanding metal stent (arrow).
‘Ragged’ edge suggesting invasion of adventitia
Tumour
Muscularis propria
Figure 9.20
Endoscopic ultrasound image of an oesophageal tumour
invading into the wall.
-
Figure 9.21
Endoscopic ultrasound (EUS)-guided
/f_i
ne-needle aspira
-
tion of a pancreatic head mass. CBD, common bile duct.



Diagnostic
Staging of oesophageal/gastric malignancy
Staging of hepatobiliary malignancy
Diagnosis of choledochal microlithiasis
Therapeutic
Biopsy of paraoesophageal lymph nodes
Biopsy of submucosal upper gastrointestinal
lesions
Biopsy of pancreaticobiliary mass
Biopsy of portal lymphadenopathy
Biopsy of left adrenal and left liver masses
Transgastric drainage of pancreatic pseudocyst
Coeliac plexus block

# Complications of diagnostic and therapeutic oesoph

Complications of diagnostic and therapeutic oesophagogastroduodenoscopy

Diagnostic upper gastrointestinal endoscopy is a safe proce dure with minimal morbidity as long as appropriate patient selection and safe sedation practices are embedded in the unit’s policy . The rate of  serious complications is approximately 1:10 /uni00A0 000. The majority of  adverse events relate to sedation and patient comorbidity . Particular caution should be exer - cised in patients with recent unstable cardiac ischaemia and respiratory compromise. Perforation can occur at any point in the upper gastrointestinal tract, including the oropharynx. It is rare during diagnostic procedures and is usually associated with inexperience. Perforation is more common in therapeutic endoscopy , particularly oesophageal dilatation and EMR/ESD for early malignancy . Early diagnosis significantly improves outcome and can potentially be managed endoscopically with clips or endoscopic suturing. Prompt management includes radiological assessment using CT/water-soluble contrast studies, strict nil by mouth, intravenous fluids and antibiotics and early review by an expe - rienced upper gastrointestinal surgeon. Summary box 9.5 Symptoms of endoscopic oesophageal perforation /uni25CF /uni25CF - /uni25CF /uni25CF /uni25CF /uni25CF low- 

Figure 9.9
A self-expanding metal stent may alle
-
viate symptoms relating to malignant oesophageal
strictures. (Left) An endoscopic view of a deployed
stent, and (right) the radiographic image.
-
Neck/chest pain
Increasing tachycardia
Dysphagia/drooling saliva
Hypotension
Abdominal pain
Surgical emphysema

Complications of diagnostic and therapeutic oesophagogastroduodenoscopy

Diagnostic upper gastrointestinal endoscopy is a safe proce dure with minimal morbidity as long as appropriate patient selection and safe sedation practices are embedded in the unit’s policy . The rate of  serious complications is approximately 1:10 /uni00A0 000. The majority of  adverse events relate to sedation and patient comorbidity . Particular caution should be exer - cised in patients with recent unstable cardiac ischaemia and respiratory compromise. Perforation can occur at any point in the upper gastrointestinal tract, including the oropharynx. It is rare during diagnostic procedures and is usually associated with inexperience. Perforation is more common in therapeutic endoscopy , particularly oesophageal dilatation and EMR/ESD for early malignancy . Early diagnosis significantly improves outcome and can potentially be managed endoscopically with clips or endoscopic suturing. Prompt management includes radiological assessment using CT/water-soluble contrast studies, strict nil by mouth, intravenous fluids and antibiotics and early review by an expe - rienced upper gastrointestinal surgeon. Summary box 9.5 Symptoms of endoscopic oesophageal perforation /uni25CF /uni25CF - /uni25CF /uni25CF /uni25CF /uni25CF low- 

Figure 9.9
A self-expanding metal stent may alle
-
viate symptoms relating to malignant oesophageal
strictures. (Left) An endoscopic view of a deployed
stent, and (right) the radiographic image.
-
Neck/chest pain
Increasing tachycardia
Dysphagia/drooling saliva
Hypotension
Abdominal pain
Surgical emphysema

# Complications of diagnostic and therapeutic oesophagogastroduodenoscopy

Complications of diagnostic and therapeutic oesophagogastroduodenoscopy

Diagnostic upper gastrointestinal endoscopy is a safe proce dure with minimal morbidity as long as appropriate patient selection and safe sedation practices are embedded in the unit’s policy . The rate of  serious complications is approximately 1:10 /uni00A0 000. The majority of  adverse events relate to sedation and patient comorbidity . Particular caution should be exer - cised in patients with recent unstable cardiac ischaemia and respiratory compromise. Perforation can occur at any point in the upper gastrointestinal tract, including the oropharynx. It is rare during diagnostic procedures and is usually associated with inexperience. Perforation is more common in therapeutic endoscopy , particularly oesophageal dilatation and EMR/ESD for early malignancy . Early diagnosis significantly improves outcome and can potentially be managed endoscopically with clips or endoscopic suturing. Prompt management includes radiological assessment using CT/water-soluble contrast studies, strict nil by mouth, intravenous fluids and antibiotics and early review by an expe - rienced upper gastrointestinal surgeon. Summary box 9.5 Symptoms of endoscopic oesophageal perforation /uni25CF /uni25CF - /uni25CF /uni25CF /uni25CF /uni25CF low- 

Figure 9.9
A self-expanding metal stent may alle
-
viate symptoms relating to malignant oesophageal
strictures. (Left) An endoscopic view of a deployed
stent, and (right) the radiographic image.
-
Neck/chest pain
Increasing tachycardia
Dysphagia/drooling saliva
Hypotension
Abdominal pain
Surgical emphysema

# ENDOSCOPIC ASSESSMENT OF THE SMALL BOWEL Introduct

ENDOSCOPIC ASSESSMENT OF THE SMALL BOWEL Introduction and indications

The requirement to visualise, biopsy and treat the small bowel is far less than in the stomach, biliary tree or colon, resulting in a time lag in technological advances. The most frequent indication is investigation of  gastrointestinal blood loss, which may present with either recurrent iron deficiency anaemia - (occult haemorrhage) or recurrent overt blood loss per rectum (cryptic haemorrhage) in a patient with normal OGD (with include the investigation of  malabsorption; the exclusion of cryptic small bowel inflammation such as Crohn’s disease in patients with diarrhoea/abdominal pain and evidence of  an inflammatory response; targeting lesions seen on radiological investigations; and surveillance for neoplasia in patients with inherited polyposis syndromes. A standard enteroscope is able to reach and biopsy lesions detected in the proximal small bowel; however, even in the most experienced hands this is limited to approximately 100 /uni00A0 cm dis tal to the pylorus, although the use of  a sti ff ening overtube may increase this somewhat. The procedure takes approximately 45 /uni00A0 minutes and may be uncomfortable, requiring high doses of sedation with the attendant incr eased risk of  perforation and sedation-related morbidity . Therefore, until recently , barium follow-through or entero clysis were the most e ff ective imaging modalities to visualise the distal duodenum, jejunum and ileum. Obviously , these techniques do not give true mucosal views, and outside spe cialist centres their decreasing use has led to diminished expertise and a reduced diagnostic yield. There have been rapid advances in axial radiological techniques such as MRI and CT enterography , which demonstrate excellent diagnos tic accuracy in this area (see Chapter 8 ). However, although these techniques may yield information about vascularity and bowel wall thickening, they do not allow direct mucosal views, have no biopsy capability and have limited scope in ter therapeutics. Historically , if  an area of  interest was outside the reach of  a standard enteroscope, direct access via enterotomy under either laparoscopic or open surgery was required. Two major clinical advances have revolutionised small bowel diag nosis and therapeutics. First, the development of  the capsule endoscope allows diagnostic mucosal views of  the entire small bowel to be obtained with minimal discomfort in unsedated patients. Second, the novel technique of  single-/doub balloon enteroscopy allows endoscopic access to the entire small bowel for biopsy and therapeutics ( Table 9.4 ). ENDOSCOPIC ASSESSMENT OF THE SMALL BOWEL Introduction and indications

The requirement to visualise, biopsy and treat the small bowel is far less than in the stomach, biliary tree or colon, resulting in a time lag in technological advances. The most frequent indication is investigation of  gastrointestinal blood loss, which may present with either recurrent iron deficiency anaemia - (occult haemorrhage) or recurrent overt blood loss per rectum (cryptic haemorrhage) in a patient with normal OGD (with include the investigation of  malabsorption; the exclusion of cryptic small bowel inflammation such as Crohn’s disease in patients with diarrhoea/abdominal pain and evidence of  an inflammatory response; targeting lesions seen on radiological investigations; and surveillance for neoplasia in patients with inherited polyposis syndromes. A standard enteroscope is able to reach and biopsy lesions detected in the proximal small bowel; however, even in the most experienced hands this is limited to approximately 100 /uni00A0 cm dis tal to the pylorus, although the use of  a sti ff ening overtube may increase this somewhat. The procedure takes approximately 45 /uni00A0 minutes and may be uncomfortable, requiring high doses of sedation with the attendant incr eased risk of  perforation and sedation-related morbidity . Therefore, until recently , barium follow-through or entero clysis were the most e ff ective imaging modalities to visualise the distal duodenum, jejunum and ileum. Obviously , these techniques do not give true mucosal views, and outside spe cialist centres their decreasing use has led to diminished expertise and a reduced diagnostic yield. There have been rapid advances in axial radiological techniques such as MRI and CT enterography , which demonstrate excellent diagnos tic accuracy in this area (see Chapter 8 ). However, although these techniques may yield information about vascularity and bowel wall thickening, they do not allow direct mucosal views, have no biopsy capability and have limited scope in ter therapeutics. Historically , if  an area of  interest was outside the reach of  a standard enteroscope, direct access via enterotomy under either laparoscopic or open surgery was required. Two major clinical advances have revolutionised small bowel diag nosis and therapeutics. First, the development of  the capsule endoscope allows diagnostic mucosal views of  the entire small bowel to be obtained with minimal discomfort in unsedated patients. Second, the novel technique of  single-/doub balloon enteroscopy allows endoscopic access to the entire small bowel for biopsy and therapeutics ( Table 9.4 ).

# ENDOSCOPIC ASSESSMENT OF THE SMALL BOWEL Introduction and indications

ENDOSCOPIC ASSESSMENT OF THE SMALL BOWEL Introduction and indications

The requirement to visualise, biopsy and treat the small bowel is far less than in the stomach, biliary tree or colon, resulting in a time lag in technological advances. The most frequent indication is investigation of  gastrointestinal blood loss, which may present with either recurrent iron deficiency anaemia - (occult haemorrhage) or recurrent overt blood loss per rectum (cryptic haemorrhage) in a patient with normal OGD (with include the investigation of  malabsorption; the exclusion of cryptic small bowel inflammation such as Crohn’s disease in patients with diarrhoea/abdominal pain and evidence of  an inflammatory response; targeting lesions seen on radiological investigations; and surveillance for neoplasia in patients with inherited polyposis syndromes. A standard enteroscope is able to reach and biopsy lesions detected in the proximal small bowel; however, even in the most experienced hands this is limited to approximately 100 /uni00A0 cm dis tal to the pylorus, although the use of  a sti ff ening overtube may increase this somewhat. The procedure takes approximately 45 /uni00A0 minutes and may be uncomfortable, requiring high doses of sedation with the attendant incr eased risk of  perforation and sedation-related morbidity . Therefore, until recently , barium follow-through or entero clysis were the most e ff ective imaging modalities to visualise the distal duodenum, jejunum and ileum. Obviously , these techniques do not give true mucosal views, and outside spe cialist centres their decreasing use has led to diminished expertise and a reduced diagnostic yield. There have been rapid advances in axial radiological techniques such as MRI and CT enterography , which demonstrate excellent diagnos tic accuracy in this area (see Chapter 8 ). However, although these techniques may yield information about vascularity and bowel wall thickening, they do not allow direct mucosal views, have no biopsy capability and have limited scope in ter therapeutics. Historically , if  an area of  interest was outside the reach of  a standard enteroscope, direct access via enterotomy under either laparoscopic or open surgery was required. Two major clinical advances have revolutionised small bowel diag nosis and therapeutics. First, the development of  the capsule endoscope allows diagnostic mucosal views of  the entire small bowel to be obtained with minimal discomfort in unsedated patients. Second, the novel technique of  single-/doub balloon enteroscopy allows endoscopic access to the entire small bowel for biopsy and therapeutics ( Table 9.4 ).

# ENDOSCOPIC RETROGRADE CHOLANGIOPANCREATOGRAPHY

ENDOSCOPIC RETROGRADE CHOLANGIOPANCREATOGRAPHY

This procedure involves the use of a side-viewing duodenos - cope, which is passed through the pylorus and into the second part of  the duodenum to visualise the papilla. This is then cannulated, either directly with a catheter or with the help of  a guidewire ( Figure 9.13 ). Occasionally a small precut is required to gain access. By altering the angle of approach - one can selectively cannulate the pancreatic duct or biliary tree, which is then visualised under fluoroscopy after contrast injection. The significant range of complica tions associated with this procedure and improvements in radiological imaging using magnetic resonance cholangiopancreatography (MRCP) have rendered much diagnostic ERCP obsolete, and thus most procedures are currently performed for therapeutic purposes. There is still a role for accessing cytology/biopsy specimens. ENDOSCOPIC RETROGRADE CHOLANGIOPANCREATOGRAPHY

This procedure involves the use of a side-viewing duodenos - cope, which is passed through the pylorus and into the second part of  the duodenum to visualise the papilla. This is then cannulated, either directly with a catheter or with the help of  a guidewire ( Figure 9.13 ). Occasionally a small precut is required to gain access. By altering the angle of approach - one can selectively cannulate the pancreatic duct or biliary tree, which is then visualised under fluoroscopy after contrast injection. The significant range of complica tions associated with this procedure and improvements in radiological imaging using magnetic resonance cholangiopancreatography (MRCP) have rendered much diagnostic ERCP obsolete, and thus most procedures are currently performed for therapeutic purposes. There is still a role for accessing cytology/biopsy specimens. ENDOSCOPIC RETROGRADE CHOLANGIOPANCREATOGRAPHY

This procedure involves the use of a side-viewing duodenos - cope, which is passed through the pylorus and into the second part of  the duodenum to visualise the papilla. This is then cannulated, either directly with a catheter or with the help of  a guidewire ( Figure 9.13 ). Occasionally a small precut is required to gain access. By altering the angle of approach - one can selectively cannulate the pancreatic duct or biliary tree, which is then visualised under fluoroscopy after contrast injection. The significant range of complica tions associated with this procedure and improvements in radiological imaging using magnetic resonance cholangiopancreatography (MRCP) have rendered much diagnostic ERCP obsolete, and thus most procedures are currently performed for therapeutic purposes. There is still a role for accessing cytology/biopsy specimens.

# ENDOSCOPY IN PATIENTS WITH DIABETES

ENDOSCOPY IN PATIENTS WITH DIABETES

As approximately 2% of  the population has diabetes, manag ing glycaemic control before and after endoscopy is an essential aspect of endoscopic practice. Each unit should develop a policy for managing diabetic control during endoscopy . Factors influencing management include the type of  diabetes procedure that is planned, the preparation/recovery time and the history of  diabetes control in the individual patient. Thus, a patient with poorly controlled insulin-dependent diabetes undergoing colonoscopy will require more input than a patient with type 2 diabetes on oral hypoglycaemic medication under going upper gastrointestinal endoscopy . All patients should bring their own medication to the unit and should be advised not to drive in case there is an alteration in their glycaemic control. Most patients can be managed using clear protocols on an outpatient basis; however , elderly patients and those with brittle control should be admitted. In general, patients with diabetes should be endoscoped first on the morning list. In complex cases the diabetes team should be involved. The majority of  endoscopies can be performed safely without the need for routine antibiotic prophylaxis. However, given that certain endoscopic procedures are associated with a significant bacteraemia ( Table 9.2 ), there are several specific situations where antibiotic cover is required to prevent either bacterial endocarditis, infection of  surgical prostheses or systemic sepsis. In general, the risk of  infection relates to the level of  bacteraemia and the risk of  the underlying medical condition. Traditionally , patients with a previous history of  endocarditis or a metallic heart valve received antibiotic prophylaxis for all endoscopic procedures, and some national guidelines still reflect this. However, in 2009 UK guidelines changed in response to the low reported incidence of  infective endocarditis in this patient group undergoing endoscopy . Patients with severe neutropenia may also require antibiotic prophylaxis for endoscopy . The antibiotic regime used will depend on local guidelines. - , the Procedures such as endoscopic percutaneous gastrostomy are associated with a significant incidence of  wound or stoma infection, particularly if  inserted for malignancy . Antibiotic - prophylaxis reduces this complication and a single intravenous injection of  co-amoxiclav should be administered before the procedure. Antibiotics are routinely used during endoscopic manipulation of  an obstructed biliary tree in which it is unlikely that complete drainage will be achieved or there is significant comorbidity . When cystic cavities are aspirated at EUS, a one- o ff dose of  a broad-spectrum antibiotic (e.g. co-amoxiclav) is recommended to prevent cyst infection. 

TABLE 9.2
Approximate incidence of bacteraemia
in immunocompetent individuals following various
procedures involving the gastrointestinal tract.
Procedure
Incidence of
a
bacteraemia (%)
Rectal digital examination
4
Proctoscopy
5
Barium enema
11
Tooth brushing
25
Dental extraction
30–60
Colonoscopy
2–4
Diagnostic upper gastrointestinal endoscopy 4
Sigmoidoscopy
6–9
ERCP (no duct occlusion)
6
ERCP (duct occluded)
11
Oesophageal varices band ligation
6
b
Oesophageal varices sclerotherapy
10–50
Oesophageal dilatation/prosthesis
34–54
Oesophageal laser therapy
35
EUS +/
−
/f_i
ne-needle aspirate
0–6
ERCP , endoscopic retrograde cholangiopancreatography; EUS,
endoscopic ultrasound.
a
Summary of published data.
b
Higher after emergency than after elective management.

ENDOSCOPY IN PATIENTS WITH DIABETES

As approximately 2% of  the population has diabetes, manag ing glycaemic control before and after endoscopy is an essential aspect of endoscopic practice. Each unit should develop a policy for managing diabetic control during endoscopy . Factors influencing management include the type of  diabetes procedure that is planned, the preparation/recovery time and the history of  diabetes control in the individual patient. Thus, a patient with poorly controlled insulin-dependent diabetes undergoing colonoscopy will require more input than a patient with type 2 diabetes on oral hypoglycaemic medication under going upper gastrointestinal endoscopy . All patients should bring their own medication to the unit and should be advised not to drive in case there is an alteration in their glycaemic control. Most patients can be managed using clear protocols on an outpatient basis; however , elderly patients and those with brittle control should be admitted. In general, patients with diabetes should be endoscoped first on the morning list. In complex cases the diabetes team should be involved. The majority of  endoscopies can be performed safely without the need for routine antibiotic prophylaxis. However, given that certain endoscopic procedures are associated with a significant bacteraemia ( Table 9.2 ), there are several specific situations where antibiotic cover is required to prevent either bacterial endocarditis, infection of  surgical prostheses or systemic sepsis. In general, the risk of  infection relates to the level of  bacteraemia and the risk of  the underlying medical condition. Traditionally , patients with a previous history of  endocarditis or a metallic heart valve received antibiotic prophylaxis for all endoscopic procedures, and some national guidelines still reflect this. However, in 2009 UK guidelines changed in response to the low reported incidence of  infective endocarditis in this patient group undergoing endoscopy . Patients with severe neutropenia may also require antibiotic prophylaxis for endoscopy . The antibiotic regime used will depend on local guidelines. - , the Procedures such as endoscopic percutaneous gastrostomy are associated with a significant incidence of  wound or stoma infection, particularly if  inserted for malignancy . Antibiotic - prophylaxis reduces this complication and a single intravenous injection of  co-amoxiclav should be administered before the procedure. Antibiotics are routinely used during endoscopic manipulation of  an obstructed biliary tree in which it is unlikely that complete drainage will be achieved or there is significant comorbidity . When cystic cavities are aspirated at EUS, a one- o ff dose of  a broad-spectrum antibiotic (e.g. co-amoxiclav) is recommended to prevent cyst infection. 

TABLE 9.2
Approximate incidence of bacteraemia
in immunocompetent individuals following various
procedures involving the gastrointestinal tract.
Procedure
Incidence of
a
bacteraemia (%)
Rectal digital examination
4
Proctoscopy
5
Barium enema
11
Tooth brushing
25
Dental extraction
30–60
Colonoscopy
2–4
Diagnostic upper gastrointestinal endoscopy 4
Sigmoidoscopy
6–9
ERCP (no duct occlusion)
6
ERCP (duct occluded)
11
Oesophageal varices band ligation
6
b
Oesophageal varices sclerotherapy
10–50
Oesophageal dilatation/prosthesis
34–54
Oesophageal laser therapy
35
EUS +/
−
/f_i
ne-needle aspirate
0–6
ERCP , endoscopic retrograde cholangiopancreatography; EUS,
endoscopic ultrasound.
a
Summary of published data.
b
Higher after emergency than after elective management.

ENDOSCOPY IN PATIENTS WITH DIABETES

As approximately 2% of  the population has diabetes, manag ing glycaemic control before and after endoscopy is an essential aspect of endoscopic practice. Each unit should develop a policy for managing diabetic control during endoscopy . Factors influencing management include the type of  diabetes procedure that is planned, the preparation/recovery time and the history of  diabetes control in the individual patient. Thus, a patient with poorly controlled insulin-dependent diabetes undergoing colonoscopy will require more input than a patient with type 2 diabetes on oral hypoglycaemic medication under going upper gastrointestinal endoscopy . All patients should bring their own medication to the unit and should be advised not to drive in case there is an alteration in their glycaemic control. Most patients can be managed using clear protocols on an outpatient basis; however , elderly patients and those with brittle control should be admitted. In general, patients with diabetes should be endoscoped first on the morning list. In complex cases the diabetes team should be involved. The majority of  endoscopies can be performed safely without the need for routine antibiotic prophylaxis. However, given that certain endoscopic procedures are associated with a significant bacteraemia ( Table 9.2 ), there are several specific situations where antibiotic cover is required to prevent either bacterial endocarditis, infection of  surgical prostheses or systemic sepsis. In general, the risk of  infection relates to the level of  bacteraemia and the risk of  the underlying medical condition. Traditionally , patients with a previous history of  endocarditis or a metallic heart valve received antibiotic prophylaxis for all endoscopic procedures, and some national guidelines still reflect this. However, in 2009 UK guidelines changed in response to the low reported incidence of  infective endocarditis in this patient group undergoing endoscopy . Patients with severe neutropenia may also require antibiotic prophylaxis for endoscopy . The antibiotic regime used will depend on local guidelines. - , the Procedures such as endoscopic percutaneous gastrostomy are associated with a significant incidence of  wound or stoma infection, particularly if  inserted for malignancy . Antibiotic - prophylaxis reduces this complication and a single intravenous injection of  co-amoxiclav should be administered before the procedure. Antibiotics are routinely used during endoscopic manipulation of  an obstructed biliary tree in which it is unlikely that complete drainage will be achieved or there is significant comorbidity . When cystic cavities are aspirated at EUS, a one- o ff dose of  a broad-spectrum antibiotic (e.g. co-amoxiclav) is recommended to prevent cyst infection. 

TABLE 9.2
Approximate incidence of bacteraemia
in immunocompetent individuals following various
procedures involving the gastrointestinal tract.
Procedure
Incidence of
a
bacteraemia (%)
Rectal digital examination
4
Proctoscopy
5
Barium enema
11
Tooth brushing
25
Dental extraction
30–60
Colonoscopy
2–4
Diagnostic upper gastrointestinal endoscopy 4
Sigmoidoscopy
6–9
ERCP (no duct occlusion)
6
ERCP (duct occluded)
11
Oesophageal varices band ligation
6
b
Oesophageal varices sclerotherapy
10–50
Oesophageal dilatation/prosthesis
34–54
Oesophageal laser therapy
35
EUS +/
−
/f_i
ne-needle aspirate
0–6
ERCP , endoscopic retrograde cholangiopancreatography; EUS,
endoscopic ultrasound.
a
Summary of published data.
b
Higher after emergency than after elective management.

# Elective endoscopy in patients on anticoagulants a

Elective endoscopy in patients on anticoagulants and antiplatelet agents

Endoscopic procedures vary in their potential to produce significant or uncontrolled bleeding. Diagnostic oesophagogas troduodenoscopy (OGD), colonoscopy , enteroscopy , diagnostic EUS and endoscopic retrograde cholangiopancreatography (ERCP) without sphincterotomy are considered low risk, as is mucosal biopsy . High-risk procedures include polypectomy , endoscopic sphincter otomy , stent placement and procedures with the potential to produce bleeding that is inaccessible or uncontrollable by endoscopic means, such as dilatation of benign or malignant strictures, percutaneous gastrostomy insertion and EUS-guided fine-needle aspiration. Likewise, the probability of a thromboembolic complication during Wenzel Treitz , 1819–1872, Professor of  Pathology , Prague, Czech Republic. depends on the underlying medical condition ( Table 9.3 ). - 

TABLE 9.3
The risk of a thromboembolic event varies
according to the underlying medical condition.
Condition
Risk
Atrial
/f_i
brillation with valvular heart disease
High
Mechanical mitral valve
High
Mechanical valve and previous thromboembolic event High
Deep vein thrombosis
Low
Uncomplicated atrial
/f_i
brillation
Low
Bioprosthetic valve
Low
Mechanical aortic valve
Low

Elective endoscopy in patients on anticoagulants and antiplatelet agents

Endoscopic procedures vary in their potential to produce significant or uncontrolled bleeding. Diagnostic oesophagogas troduodenoscopy (OGD), colonoscopy , enteroscopy , diagnostic EUS and endoscopic retrograde cholangiopancreatography (ERCP) without sphincterotomy are considered low risk, as is mucosal biopsy . High-risk procedures include polypectomy , endoscopic sphincter otomy , stent placement and procedures with the potential to produce bleeding that is inaccessible or uncontrollable by endoscopic means, such as dilatation of benign or malignant strictures, percutaneous gastrostomy insertion and EUS-guided fine-needle aspiration. Likewise, the probability of a thromboembolic complication during Wenzel Treitz , 1819–1872, Professor of  Pathology , Prague, Czech Republic. depends on the underlying medical condition ( Table 9.3 ). - 

TABLE 9.3
The risk of a thromboembolic event varies
according to the underlying medical condition.
Condition
Risk
Atrial
/f_i
brillation with valvular heart disease
High
Mechanical mitral valve
High
Mechanical valve and previous thromboembolic event High
Deep vein thrombosis
Low
Uncomplicated atrial
/f_i
brillation
Low
Bioprosthetic valve
Low
Mechanical aortic valve
Low

# Elective endoscopy in patients on anticoagulants and antiplatelet agents

Elective endoscopy in patients on anticoagulants and antiplatelet agents

Endoscopic procedures vary in their potential to produce significant or uncontrolled bleeding. Diagnostic oesophagogas troduodenoscopy (OGD), colonoscopy , enteroscopy , diagnostic EUS and endoscopic retrograde cholangiopancreatography (ERCP) without sphincterotomy are considered low risk, as is mucosal biopsy . High-risk procedures include polypectomy , endoscopic sphincter otomy , stent placement and procedures with the potential to produce bleeding that is inaccessible or uncontrollable by endoscopic means, such as dilatation of benign or malignant strictures, percutaneous gastrostomy insertion and EUS-guided fine-needle aspiration. Likewise, the probability of a thromboembolic complication during Wenzel Treitz , 1819–1872, Professor of  Pathology , Prague, Czech Republic. depends on the underlying medical condition ( Table 9.3 ). - 

TABLE 9.3
The risk of a thromboembolic event varies
according to the underlying medical condition.
Condition
Risk
Atrial
/f_i
brillation with valvular heart disease
High
Mechanical mitral valve
High
Mechanical valve and previous thromboembolic event High
Deep vein thrombosis
Low
Uncomplicated atrial
/f_i
brillation
Low
Bioprosthetic valve
Low
Mechanical aortic valve
Low

# Equipment

Equipment

A full description of  all available endoscopic equipment is beyond the scope of  this chapter. However, each unit should have a su ffi cient range of  endoscopes, processors and accesso - ries as dictated by the local case mix and su ffi cient endoscope numbers to ensure smooth service provision. These should include both forward- and lateral-viewing gastroscopes, an enteroscope for proximal small bowel visualisation and a centres require capsule endoscopy and a single-/double-bal loon enteroscope for ileojejunal visualisation and therapeutics. Larger centres will require linear and radial EUS, particularly if they specialise in gastrointestinal and hepatobiliary malignancy . An electrosurgical unit is the cornerstone of many therapeutic procedures, and this may be supplemented by argon plasma coagulation (APC), laser units and radiofrequency ablation for advanced therapeutics. Equipment

A full description of  all available endoscopic equipment is beyond the scope of  this chapter. However, each unit should have a su ffi cient range of  endoscopes, processors and accesso - ries as dictated by the local case mix and su ffi cient endoscope numbers to ensure smooth service provision. These should include both forward- and lateral-viewing gastroscopes, an enteroscope for proximal small bowel visualisation and a centres require capsule endoscopy and a single-/double-bal loon enteroscope for ileojejunal visualisation and therapeutics. Larger centres will require linear and radial EUS, particularly if they specialise in gastrointestinal and hepatobiliary malignancy . An electrosurgical unit is the cornerstone of many therapeutic procedures, and this may be supplemented by argon plasma coagulation (APC), laser units and radiofrequency ablation for advanced therapeutics. Equipment

A full description of  all available endoscopic equipment is beyond the scope of  this chapter. However, each unit should have a su ffi cient range of  endoscopes, processors and accesso - ries as dictated by the local case mix and su ffi cient endoscope numbers to ensure smooth service provision. These should include both forward- and lateral-viewing gastroscopes, an enteroscope for proximal small bowel visualisation and a centres require capsule endoscopy and a single-/double-bal loon enteroscope for ileojejunal visualisation and therapeutics. Larger centres will require linear and radial EUS, particularly if they specialise in gastrointestinal and hepatobiliary malignancy . An electrosurgical unit is the cornerstone of many therapeutic procedures, and this may be supplemented by argon plasma coagulation (APC), laser units and radiofrequency ablation for advanced therapeutics.

# HISTORY OF ENDOSCOPY

HISTORY OF ENDOSCOPY

- Over the last 50 years, endoscopy has become a powerful - diagnostic and therapeutic tool. However, its development required two obvious but formidable barriers to be overcome. - First, the gastrointestinal tract is rather long and tortuous and, second, no natural light shines through the available orifices! Therefore, successful visualisation of  anything beyond the - distal extremities requires a flexible instrument with an intrinsic light source that can transmit images to the operator. The breakthrough was the discovery that images could be transmitted using flexible quartz fibres. Although this was first described in the late 1920s, it was not until 1954 that Hopkins built a model of  a flexible fibre imaging device. The availability of  highly transparent optical quality glass led to the development in 1958 of  the first flexible fibreoptic gastroscope by Larry Curtiss, a graduate student in physics, and Basil Hirschowitz, a trainee in gastroenterology . Over the next 30 years, the fibrescope evolved to allow exam ination of  the upper gastrointestinal tract, the biliary system and the colon. In parallel with advances in diagnostic ability , a range of  therapeutic procedures was developed ( Table 9.1 Although the fibreoptic endoscope has been the workhorse of many endoscopy units ov er the last three decades, its obsoles cence was guaranteed by the invention of  the charge-coupled device (CCD) in the 1960s, which allowed the creation of  a digital electronic image, permitting endoscopic images to be processed by a computer and transmitted to television screens. T hus, the modern endoscope was born ( Figure 9.1 ). Larry E Curtiss , physicist, University of  Michigan, Ann Arbour, MI, USA. Basil I Hirschowitz , 1925–2013, Professor of  Medicine, University of  Alabama, Birmingham, AL, USA. tinue with the replacement of  much diagnostic endoscopy with capsule endoscopy and virtual imaging. Enhanced resolution with high-definition operating systems, dye and digital chromo - endoscopy and e ven histological-grade images have increased the diagnostic yield of  surveillance procedures. EUS allows diagnosis and therapy to extend beyond the mucosal surface of  the intestine. Endoscopy has become increasingly therapeu - tic and historical divisions betw een medicine, radiology and surgery will become progressively blurred. As the complexity of  the procedures increases, the distinction between special - ist and general endoscopists will become mor e definite. This reinforces the need for all endoscopic practitioners to have a detailed understanding of  the units in which they work and the instruments that they use. 

endoscopy.
1958
Development of
/f_i
breoptic gastroscope
1968
Endoscopic retrograde pancreatography
1969
Colonoscopic polypectomy
1970
Endoscopic retrograde cholangiography
1974
Endoscopic sphincterotomy (with bile duct stone
extraction)
1979
Percutaneous endoscopic gastrostomy
1980
Endoscopic injection sclerotherapy
1980
Endoscopic ultrasonography
1983
Electronic (charge-coupled device) endoscope
1985
Endoscopic control of upper gastrointestinal bleeding
1990
Endoscopic variceal ligation
1996
Introduction of self-expanding metal stents
2008
Endomicroscopy delivers histological mucosal
de
/f_i
nition
Figure 9.1
Photograph of a standard gastroscope and colonoscope.

HISTORY OF ENDOSCOPY

- Over the last 50 years, endoscopy has become a powerful - diagnostic and therapeutic tool. However, its development required two obvious but formidable barriers to be overcome. - First, the gastrointestinal tract is rather long and tortuous and, second, no natural light shines through the available orifices! Therefore, successful visualisation of  anything beyond the - distal extremities requires a flexible instrument with an intrinsic light source that can transmit images to the operator. The breakthrough was the discovery that images could be transmitted using flexible quartz fibres. Although this was first described in the late 1920s, it was not until 1954 that Hopkins built a model of  a flexible fibre imaging device. The availability of  highly transparent optical quality glass led to the development in 1958 of  the first flexible fibreoptic gastroscope by Larry Curtiss, a graduate student in physics, and Basil Hirschowitz, a trainee in gastroenterology . Over the next 30 years, the fibrescope evolved to allow exam ination of  the upper gastrointestinal tract, the biliary system and the colon. In parallel with advances in diagnostic ability , a range of  therapeutic procedures was developed ( Table 9.1 Although the fibreoptic endoscope has been the workhorse of many endoscopy units ov er the last three decades, its obsoles cence was guaranteed by the invention of  the charge-coupled device (CCD) in the 1960s, which allowed the creation of  a digital electronic image, permitting endoscopic images to be processed by a computer and transmitted to television screens. T hus, the modern endoscope was born ( Figure 9.1 ). Larry E Curtiss , physicist, University of  Michigan, Ann Arbour, MI, USA. Basil I Hirschowitz , 1925–2013, Professor of  Medicine, University of  Alabama, Birmingham, AL, USA. tinue with the replacement of  much diagnostic endoscopy with capsule endoscopy and virtual imaging. Enhanced resolution with high-definition operating systems, dye and digital chromo - endoscopy and e ven histological-grade images have increased the diagnostic yield of  surveillance procedures. EUS allows diagnosis and therapy to extend beyond the mucosal surface of  the intestine. Endoscopy has become increasingly therapeu - tic and historical divisions betw een medicine, radiology and surgery will become progressively blurred. As the complexity of  the procedures increases, the distinction between special - ist and general endoscopists will become mor e definite. This reinforces the need for all endoscopic practitioners to have a detailed understanding of  the units in which they work and the instruments that they use. 

endoscopy.
1958
Development of
/f_i
breoptic gastroscope
1968
Endoscopic retrograde pancreatography
1969
Colonoscopic polypectomy
1970
Endoscopic retrograde cholangiography
1974
Endoscopic sphincterotomy (with bile duct stone
extraction)
1979
Percutaneous endoscopic gastrostomy
1980
Endoscopic injection sclerotherapy
1980
Endoscopic ultrasonography
1983
Electronic (charge-coupled device) endoscope
1985
Endoscopic control of upper gastrointestinal bleeding
1990
Endoscopic variceal ligation
1996
Introduction of self-expanding metal stents
2008
Endomicroscopy delivers histological mucosal
de
/f_i
nition
Figure 9.1
Photograph of a standard gastroscope and colonoscope.

HISTORY OF ENDOSCOPY

- Over the last 50 years, endoscopy has become a powerful - diagnostic and therapeutic tool. However, its development required two obvious but formidable barriers to be overcome. - First, the gastrointestinal tract is rather long and tortuous and, second, no natural light shines through the available orifices! Therefore, successful visualisation of  anything beyond the - distal extremities requires a flexible instrument with an intrinsic light source that can transmit images to the operator. The breakthrough was the discovery that images could be transmitted using flexible quartz fibres. Although this was first described in the late 1920s, it was not until 1954 that Hopkins built a model of  a flexible fibre imaging device. The availability of  highly transparent optical quality glass led to the development in 1958 of  the first flexible fibreoptic gastroscope by Larry Curtiss, a graduate student in physics, and Basil Hirschowitz, a trainee in gastroenterology . Over the next 30 years, the fibrescope evolved to allow exam ination of  the upper gastrointestinal tract, the biliary system and the colon. In parallel with advances in diagnostic ability , a range of  therapeutic procedures was developed ( Table 9.1 Although the fibreoptic endoscope has been the workhorse of many endoscopy units ov er the last three decades, its obsoles cence was guaranteed by the invention of  the charge-coupled device (CCD) in the 1960s, which allowed the creation of  a digital electronic image, permitting endoscopic images to be processed by a computer and transmitted to television screens. T hus, the modern endoscope was born ( Figure 9.1 ). Larry E Curtiss , physicist, University of  Michigan, Ann Arbour, MI, USA. Basil I Hirschowitz , 1925–2013, Professor of  Medicine, University of  Alabama, Birmingham, AL, USA. tinue with the replacement of  much diagnostic endoscopy with capsule endoscopy and virtual imaging. Enhanced resolution with high-definition operating systems, dye and digital chromo - endoscopy and e ven histological-grade images have increased the diagnostic yield of  surveillance procedures. EUS allows diagnosis and therapy to extend beyond the mucosal surface of  the intestine. Endoscopy has become increasingly therapeu - tic and historical divisions betw een medicine, radiology and surgery will become progressively blurred. As the complexity of  the procedures increases, the distinction between special - ist and general endoscopists will become mor e definite. This reinforces the need for all endoscopic practitioners to have a detailed understanding of  the units in which they work and the instruments that they use. 

endoscopy.
1958
Development of
/f_i
breoptic gastroscope
1968
Endoscopic retrograde pancreatography
1969
Colonoscopic polypectomy
1970
Endoscopic retrograde cholangiography
1974
Endoscopic sphincterotomy (with bile duct stone
extraction)
1979
Percutaneous endoscopic gastrostomy
1980
Endoscopic injection sclerotherapy
1980
Endoscopic ultrasonography
1983
Electronic (charge-coupled device) endoscope
1985
Endoscopic control of upper gastrointestinal bleeding
1990
Endoscopic variceal ligation
1996
Introduction of self-expanding metal stents
2008
Endomicroscopy delivers histological mucosal
de
/f_i
nition
Figure 9.1
Photograph of a standard gastroscope and colonoscope.

# Indications for oesophagogastroduodenoscopy

Indications for oesophagogastroduodenoscopy

A full assessment of  the role of  OGD is outside the scope of  this chapter. It will vary with local circumstances and the availability of alternative diagnostic techniques. OGD is usually appropriate when a patient’s symptoms are persistent despite appropriate empirical therapy or are associated with warning signs such as intractable vomiting, anaemia, weight loss, dysphagia or bleeding. It is also part of  the diagnostic work-up for patients with anaemia, symptoms of 

• Diagnostic procedures +/– biopsy
• Biliary or pancreatic stenting
• Device-assisted enteroscopy without polypectomy
Continue warfarin
Warfarin
Check INR 1 week before endoscopy
• If INR is within therapeutic range continue
usual daily dose
• If INR is above therapeutic range but <5 reduce
daily dose until INR returns to therapeutic range
High-risk procedure
• Polypectomy
• ERCP with sphincterotomy
• EMR/ESD
• Dilatation of strictures
Warfarin
Low-risk condition
High-risk condition
• Prosthetic metal heart valve in mitral or aortic
• Xenograft heart valve
position
• AF without high-risk factors
• Prosthetic heart valve and AF
(CHADS
≤4)
2
• AF and mitral stenosis
• >3 months after VTE
• AF with previous stroke/TIA and 3 or more of:
• Congestive cardiac failure
a
• Hypertension
• Age >75 years
• Diabetes mellitus
• AF and stroke/TIA within 3 months
• <3 months after VTE
• Previous VTE on anticoagulation
Stop warfarin for 5 days before
Stop warfarin for 5 days before
endoscopy
• Check INR prior procedure to ensure
• Start LMWH 2 days after stopping warfarin
INR <5
• Omit LMWH on day of procedure
• Restart warfarin evening of the procedure
• Restart warfarin evening of the procedure
with usual daily dose
with usual daily dose
• Check INR 1 week later to ensure
• Continue LMWH until INR adequate
adequate anticoagulation
Low-risk condition
• Ischaemic heart disease without coronary stent
• Cerebrovascular disease
• Peripheral vascular disease
Stop clopidogrel, prasugrel or ticagrelor
7 days before endoscopy
• Continue aspirin if already prescribed
• Restart clopidogrel, prasugrel or ticagrelor 1–2
days after procedure
Figure 9.2
British Society of Gastroenterology and European Society of Gastrointestinal Endoscopy 2021 guidelines for management of endos
copy in patients on antiplatelet or anticoagulant therapy. AF , atrial
/f_i
brillation; CHADS, score for stroke risk assessment in atrial
/f_i
brillation;
DOAC, direct oral anticoagulant; eGFR, estimated glomerular
/f_i
ltration rate; EMR, endoscopic mucosal resection; ERCP , endoscopic
cholangiopancreatography; ESD, endoscopic submucosal dissection; EUS, endoscopic ultrasound; INR, international normalised ratio; LMWH,
low molecular weight heparin; PEG, percutaneous endoscopic gastroenterostomy; TIA, transient ischaemic attack; VTE, venous thrombo
a
embolism.
Blood pressure >140/90 mmHg or on antihypertensive medication.
c
Depends on haemorrhagic and thrombotic risk; consider extending interval for ESD. (Adapted from Veitch
• Oesophageal, enteral or colonic stenting
• EUS without sampling or interventional therapy
DOAC
• Dabigatran
Omit DOAC on
• Rivaroxaban
morning of the
• Apixaban
procedure
• Edoxaban
• Therapy of varices
• PEG
• EUS-guided sampling or with interventional therapy
• Oesophageal or gastric radiofrequency ablation
DOAC
Clopidogrel
• Dabigatran
• Apixaban
Prasugrel
• Rivaroxaban
• Edoxaban
Ticagrelor
Take last dose of drug 3 days
before endoscopy
• For dabigatran with CrCI (eGFR)
30–50 mL/min take last dose 5 days
before procedure
• In any patients with rapidly
deteriorating renal function a
haematologist should be consulted
• Restart DOAC 2–3 days after
c
procedure
b
endoscopy
High-risk condition
• Coronary artery stents
Discuss strategy with consultant
interventional cardiologist
• Consider temporary cessation of P2Y12
receptor antagonist if:
• 6–12 months after insertion
of drug-eluting coronary stent
• >1 month after insertion of
bare metal coronary stent
• Continue aspirin
-
retrograde
-
b
Previous VTE on anticoagulation and target INR now 3.5.
et al
. 2021.)

malabsorption and chronic diarrhoea. However, increasing ease of  access to OGD with the availability of  ‘open access’ endoscopy has resulted in a significant number of  unnecessary procedures being performed in young patients with dyspepsia or gastro-oesophageal reflux disease (GORD). This has led to a number of  international gastroenterology societies proposing guidelines for the management of  dyspepsia and GORD, including the empirical use of  acid suppression and non-invasive H. pylori tests, such as urease breath tests and stool antigen assay (e.g. the National Institute for Health and Care Excellence guidelines on dyspepsia: https://www .nice.org.uk/ guidance/cg184/chapter/1-recommendations). In addition 

(c)
Figure 9.3
A normal upper gastrointestinal endoscopy showing the gastro-oesophageal junction
the gastric antrum
(c)
and the second part of the duodenum
(a)
Figure 9.4
Grade 2 oesophageal varices
(a)
, which can be treated by the application of bands to ligate the vessel and reduce blood
/f_l
ow
(d)
(a)
, the gastric fundus in the ‘J’ position
(b)
,
(d)
.
(b)
(b)
.

the surveillance of  neoplasia development in high-risk patient groups, such as those with genetic conditions such as familial adenomatous polyposis and premalignant conditions such as Barrett’s oesophagus (see Chapter 66 ). Indications for oesophagogastroduodenoscopy

A full assessment of  the role of  OGD is outside the scope of  this chapter. It will vary with local circumstances and the availability of alternative diagnostic techniques. OGD is usually appropriate when a patient’s symptoms are persistent despite appropriate empirical therapy or are associated with warning signs such as intractable vomiting, anaemia, weight loss, dysphagia or bleeding. It is also part of  the diagnostic work-up for patients with anaemia, symptoms of 

• Diagnostic procedures +/– biopsy
• Biliary or pancreatic stenting
• Device-assisted enteroscopy without polypectomy
Continue warfarin
Warfarin
Check INR 1 week before endoscopy
• If INR is within therapeutic range continue
usual daily dose
• If INR is above therapeutic range but <5 reduce
daily dose until INR returns to therapeutic range
High-risk procedure
• Polypectomy
• ERCP with sphincterotomy
• EMR/ESD
• Dilatation of strictures
Warfarin
Low-risk condition
High-risk condition
• Prosthetic metal heart valve in mitral or aortic
• Xenograft heart valve
position
• AF without high-risk factors
• Prosthetic heart valve and AF
(CHADS
≤4)
2
• AF and mitral stenosis
• >3 months after VTE
• AF with previous stroke/TIA and 3 or more of:
• Congestive cardiac failure
a
• Hypertension
• Age >75 years
• Diabetes mellitus
• AF and stroke/TIA within 3 months
• <3 months after VTE
• Previous VTE on anticoagulation
Stop warfarin for 5 days before
Stop warfarin for 5 days before
endoscopy
• Check INR prior procedure to ensure
• Start LMWH 2 days after stopping warfarin
INR <5
• Omit LMWH on day of procedure
• Restart warfarin evening of the procedure
• Restart warfarin evening of the procedure
with usual daily dose
with usual daily dose
• Check INR 1 week later to ensure
• Continue LMWH until INR adequate
adequate anticoagulation
Low-risk condition
• Ischaemic heart disease without coronary stent
• Cerebrovascular disease
• Peripheral vascular disease
Stop clopidogrel, prasugrel or ticagrelor
7 days before endoscopy
• Continue aspirin if already prescribed
• Restart clopidogrel, prasugrel or ticagrelor 1–2
days after procedure
Figure 9.2
British Society of Gastroenterology and European Society of Gastrointestinal Endoscopy 2021 guidelines for management of endos
copy in patients on antiplatelet or anticoagulant therapy. AF , atrial
/f_i
brillation; CHADS, score for stroke risk assessment in atrial
/f_i
brillation;
DOAC, direct oral anticoagulant; eGFR, estimated glomerular
/f_i
ltration rate; EMR, endoscopic mucosal resection; ERCP , endoscopic
cholangiopancreatography; ESD, endoscopic submucosal dissection; EUS, endoscopic ultrasound; INR, international normalised ratio; LMWH,
low molecular weight heparin; PEG, percutaneous endoscopic gastroenterostomy; TIA, transient ischaemic attack; VTE, venous thrombo
a
embolism.
Blood pressure >140/90 mmHg or on antihypertensive medication.
c
Depends on haemorrhagic and thrombotic risk; consider extending interval for ESD. (Adapted from Veitch
• Oesophageal, enteral or colonic stenting
• EUS without sampling or interventional therapy
DOAC
• Dabigatran
Omit DOAC on
• Rivaroxaban
morning of the
• Apixaban
procedure
• Edoxaban
• Therapy of varices
• PEG
• EUS-guided sampling or with interventional therapy
• Oesophageal or gastric radiofrequency ablation
DOAC
Clopidogrel
• Dabigatran
• Apixaban
Prasugrel
• Rivaroxaban
• Edoxaban
Ticagrelor
Take last dose of drug 3 days
before endoscopy
• For dabigatran with CrCI (eGFR)
30–50 mL/min take last dose 5 days
before procedure
• In any patients with rapidly
deteriorating renal function a
haematologist should be consulted
• Restart DOAC 2–3 days after
c
procedure
b
endoscopy
High-risk condition
• Coronary artery stents
Discuss strategy with consultant
interventional cardiologist
• Consider temporary cessation of P2Y12
receptor antagonist if:
• 6–12 months after insertion
of drug-eluting coronary stent
• >1 month after insertion of
bare metal coronary stent
• Continue aspirin
-
retrograde
-
b
Previous VTE on anticoagulation and target INR now 3.5.
et al
. 2021.)

malabsorption and chronic diarrhoea. However, increasing ease of  access to OGD with the availability of  ‘open access’ endoscopy has resulted in a significant number of  unnecessary procedures being performed in young patients with dyspepsia or gastro-oesophageal reflux disease (GORD). This has led to a number of  international gastroenterology societies proposing guidelines for the management of  dyspepsia and GORD, including the empirical use of  acid suppression and non-invasive H. pylori tests, such as urease breath tests and stool antigen assay (e.g. the National Institute for Health and Care Excellence guidelines on dyspepsia: https://www .nice.org.uk/ guidance/cg184/chapter/1-recommendations). In addition 

(c)
Figure 9.3
A normal upper gastrointestinal endoscopy showing the gastro-oesophageal junction
the gastric antrum
(c)
and the second part of the duodenum
(a)
Figure 9.4
Grade 2 oesophageal varices
(a)
, which can be treated by the application of bands to ligate the vessel and reduce blood
/f_l
ow
(d)
(a)
, the gastric fundus in the ‘J’ position
(b)
,
(d)
.
(b)
(b)
.

the surveillance of  neoplasia development in high-risk patient groups, such as those with genetic conditions such as familial adenomatous polyposis and premalignant conditions such as Barrett’s oesophagus (see Chapter 66 ). Indications for oesophagogastroduodenoscopy

A full assessment of  the role of  OGD is outside the scope of  this chapter. It will vary with local circumstances and the availability of alternative diagnostic techniques. OGD is usually appropriate when a patient’s symptoms are persistent despite appropriate empirical therapy or are associated with warning signs such as intractable vomiting, anaemia, weight loss, dysphagia or bleeding. It is also part of  the diagnostic work-up for patients with anaemia, symptoms of 

• Diagnostic procedures +/– biopsy
• Biliary or pancreatic stenting
• Device-assisted enteroscopy without polypectomy
Continue warfarin
Warfarin
Check INR 1 week before endoscopy
• If INR is within therapeutic range continue
usual daily dose
• If INR is above therapeutic range but <5 reduce
daily dose until INR returns to therapeutic range
High-risk procedure
• Polypectomy
• ERCP with sphincterotomy
• EMR/ESD
• Dilatation of strictures
Warfarin
Low-risk condition
High-risk condition
• Prosthetic metal heart valve in mitral or aortic
• Xenograft heart valve
position
• AF without high-risk factors
• Prosthetic heart valve and AF
(CHADS
≤4)
2
• AF and mitral stenosis
• >3 months after VTE
• AF with previous stroke/TIA and 3 or more of:
• Congestive cardiac failure
a
• Hypertension
• Age >75 years
• Diabetes mellitus
• AF and stroke/TIA within 3 months
• <3 months after VTE
• Previous VTE on anticoagulation
Stop warfarin for 5 days before
Stop warfarin for 5 days before
endoscopy
• Check INR prior procedure to ensure
• Start LMWH 2 days after stopping warfarin
INR <5
• Omit LMWH on day of procedure
• Restart warfarin evening of the procedure
• Restart warfarin evening of the procedure
with usual daily dose
with usual daily dose
• Check INR 1 week later to ensure
• Continue LMWH until INR adequate
adequate anticoagulation
Low-risk condition
• Ischaemic heart disease without coronary stent
• Cerebrovascular disease
• Peripheral vascular disease
Stop clopidogrel, prasugrel or ticagrelor
7 days before endoscopy
• Continue aspirin if already prescribed
• Restart clopidogrel, prasugrel or ticagrelor 1–2
days after procedure
Figure 9.2
British Society of Gastroenterology and European Society of Gastrointestinal Endoscopy 2021 guidelines for management of endos
copy in patients on antiplatelet or anticoagulant therapy. AF , atrial
/f_i
brillation; CHADS, score for stroke risk assessment in atrial
/f_i
brillation;
DOAC, direct oral anticoagulant; eGFR, estimated glomerular
/f_i
ltration rate; EMR, endoscopic mucosal resection; ERCP , endoscopic
cholangiopancreatography; ESD, endoscopic submucosal dissection; EUS, endoscopic ultrasound; INR, international normalised ratio; LMWH,
low molecular weight heparin; PEG, percutaneous endoscopic gastroenterostomy; TIA, transient ischaemic attack; VTE, venous thrombo
a
embolism.
Blood pressure >140/90 mmHg or on antihypertensive medication.
c
Depends on haemorrhagic and thrombotic risk; consider extending interval for ESD. (Adapted from Veitch
• Oesophageal, enteral or colonic stenting
• EUS without sampling or interventional therapy
DOAC
• Dabigatran
Omit DOAC on
• Rivaroxaban
morning of the
• Apixaban
procedure
• Edoxaban
• Therapy of varices
• PEG
• EUS-guided sampling or with interventional therapy
• Oesophageal or gastric radiofrequency ablation
DOAC
Clopidogrel
• Dabigatran
• Apixaban
Prasugrel
• Rivaroxaban
• Edoxaban
Ticagrelor
Take last dose of drug 3 days
before endoscopy
• For dabigatran with CrCI (eGFR)
30–50 mL/min take last dose 5 days
before procedure
• In any patients with rapidly
deteriorating renal function a
haematologist should be consulted
• Restart DOAC 2–3 days after
c
procedure
b
endoscopy
High-risk condition
• Coronary artery stents
Discuss strategy with consultant
interventional cardiologist
• Consider temporary cessation of P2Y12
receptor antagonist if:
• 6–12 months after insertion
of drug-eluting coronary stent
• >1 month after insertion of
bare metal coronary stent
• Continue aspirin
-
retrograde
-
b
Previous VTE on anticoagulation and target INR now 3.5.
et al
. 2021.)

malabsorption and chronic diarrhoea. However, increasing ease of  access to OGD with the availability of  ‘open access’ endoscopy has resulted in a significant number of  unnecessary procedures being performed in young patients with dyspepsia or gastro-oesophageal reflux disease (GORD). This has led to a number of  international gastroenterology societies proposing guidelines for the management of  dyspepsia and GORD, including the empirical use of  acid suppression and non-invasive H. pylori tests, such as urease breath tests and stool antigen assay (e.g. the National Institute for Health and Care Excellence guidelines on dyspepsia: https://www .nice.org.uk/ guidance/cg184/chapter/1-recommendations). In addition 

(c)
Figure 9.3
A normal upper gastrointestinal endoscopy showing the gastro-oesophageal junction
the gastric antrum
(c)
and the second part of the duodenum
(a)
Figure 9.4
Grade 2 oesophageal varices
(a)
, which can be treated by the application of bands to ligate the vessel and reduce blood
/f_l
ow
(d)
(a)
, the gastric fundus in the ‘J’ position
(b)
,
(d)
.
(b)
(b)
.

the surveillance of  neoplasia development in high-risk patient groups, such as those with genetic conditions such as familial adenomatous polyposis and premalignant conditions such as Barrett’s oesophagus (see Chapter 66 ).

# Instrument decontamination

Instrument decontamination

Endoscopes will not withstand steam-based autoclaving and therefore require high-level disinfection between cases to prevent transmission of  infection. Although accessories may be autoclaved, best practice requires the use of  disposable single-use items whenever possible. All equipment should be decontaminated to an identical standard whether for use on immunocompromised/infected patients or not. This process involves two equally important stages: first, removal of physical debris from the internal and external surfaces of  the instrument and, second, chemical neutralisation of  all microbiological agents. A variety of agents are available and endoscopists should familiarise themselves with the agent in use in their department. In 2020 the British Society of Gastroenterology updated its guidelines for decontamination of endoscopes (see Further reading). Care should be applied to the decontamina tion of  duodenoscopes because of  reports of  transmission of multiresistant bacteria ( Summary box 9.1 ). Summary box 9.1 Disinfection of endoscopes /uni25CF /uni25CF /uni25CF /uni25CF There are currently no reliable means of  decontaminat ing scopes from contact with prion-associated conditions such as variant Creutzfeldt–Jakob disease (vCJD), although risk of transmission of  this is considered very low . If  an ‘invasive’ procedure (where gut m ucosa is breached and an unsheathed accessory withdrawn through the endoscope working chan nel) is conducted in a patient with known or possible vCJD, the endoscope needs to be quarantined after use. The perfor mance of  an invasive procedure in a patient at risk of  vCJD owing to receipt of  pooled plasma concentrates is no longer Hans Gerhard Creutzfeldt , 1885–1964, neurologist, Kiel, Germany . Alfons Marie Jakob , 1884–1931, neurologist, Hamburg, Germany . - su ffi cient, but the endoscope should be decontaminated sep - arately from others with a single-use disinfectant. There is no longer a requirement to quarantine the endoscope pr ovided that routine traceability data can be demonstrated. 

All channels must be brushed and irrigated throughout the
disinfection process
All instruments and accessories should be traceable to each
use, patient and cleaning cycle
All staff should be trained and protected (particularly if
glutaraldehyde is used in view of its immune-sensitising
properties)
Regular monitoring of disinfectant power and microbiological
contamination should be performed

Instrument decontamination

Endoscopes will not withstand steam-based autoclaving and therefore require high-level disinfection between cases to prevent transmission of  infection. Although accessories may be autoclaved, best practice requires the use of  disposable single-use items whenever possible. All equipment should be decontaminated to an identical standard whether for use on immunocompromised/infected patients or not. This process involves two equally important stages: first, removal of physical debris from the internal and external surfaces of  the instrument and, second, chemical neutralisation of  all microbiological agents. A variety of agents are available and endoscopists should familiarise themselves with the agent in use in their department. In 2020 the British Society of Gastroenterology updated its guidelines for decontamination of endoscopes (see Further reading). Care should be applied to the decontamina tion of  duodenoscopes because of  reports of  transmission of multiresistant bacteria ( Summary box 9.1 ). Summary box 9.1 Disinfection of endoscopes /uni25CF /uni25CF /uni25CF /uni25CF There are currently no reliable means of  decontaminat ing scopes from contact with prion-associated conditions such as variant Creutzfeldt–Jakob disease (vCJD), although risk of transmission of  this is considered very low . If  an ‘invasive’ procedure (where gut m ucosa is breached and an unsheathed accessory withdrawn through the endoscope working chan nel) is conducted in a patient with known or possible vCJD, the endoscope needs to be quarantined after use. The perfor mance of  an invasive procedure in a patient at risk of  vCJD owing to receipt of  pooled plasma concentrates is no longer Hans Gerhard Creutzfeldt , 1885–1964, neurologist, Kiel, Germany . Alfons Marie Jakob , 1884–1931, neurologist, Hamburg, Germany . - su ffi cient, but the endoscope should be decontaminated sep - arately from others with a single-use disinfectant. There is no longer a requirement to quarantine the endoscope pr ovided that routine traceability data can be demonstrated. 

All channels must be brushed and irrigated throughout the
disinfection process
All instruments and accessories should be traceable to each
use, patient and cleaning cycle
All staff should be trained and protected (particularly if
glutaraldehyde is used in view of its immune-sensitising
properties)
Regular monitoring of disinfectant power and microbiological
contamination should be performed

Instrument decontamination

Endoscopes will not withstand steam-based autoclaving and therefore require high-level disinfection between cases to prevent transmission of  infection. Although accessories may be autoclaved, best practice requires the use of  disposable single-use items whenever possible. All equipment should be decontaminated to an identical standard whether for use on immunocompromised/infected patients or not. This process involves two equally important stages: first, removal of physical debris from the internal and external surfaces of  the instrument and, second, chemical neutralisation of  all microbiological agents. A variety of agents are available and endoscopists should familiarise themselves with the agent in use in their department. In 2020 the British Society of Gastroenterology updated its guidelines for decontamination of endoscopes (see Further reading). Care should be applied to the decontamina tion of  duodenoscopes because of  reports of  transmission of multiresistant bacteria ( Summary box 9.1 ). Summary box 9.1 Disinfection of endoscopes /uni25CF /uni25CF /uni25CF /uni25CF There are currently no reliable means of  decontaminat ing scopes from contact with prion-associated conditions such as variant Creutzfeldt–Jakob disease (vCJD), although risk of transmission of  this is considered very low . If  an ‘invasive’ procedure (where gut m ucosa is breached and an unsheathed accessory withdrawn through the endoscope working chan nel) is conducted in a patient with known or possible vCJD, the endoscope needs to be quarantined after use. The perfor mance of  an invasive procedure in a patient at risk of  vCJD owing to receipt of  pooled plasma concentrates is no longer Hans Gerhard Creutzfeldt , 1885–1964, neurologist, Kiel, Germany . Alfons Marie Jakob , 1884–1931, neurologist, Hamburg, Germany . - su ffi cient, but the endoscope should be decontaminated sep - arately from others with a single-use disinfectant. There is no longer a requirement to quarantine the endoscope pr ovided that routine traceability data can be demonstrated. 

All channels must be brushed and irrigated throughout the
disinfection process
All instruments and accessories should be traceable to each
use, patient and cleaning cycle
All staff should be trained and protected (particularly if
glutaraldehyde is used in view of its immune-sensitising
properties)
Regular monitoring of disinfectant power and microbiological
contamination should be performed

# Introduction

INTRODUCTION

The gastrointestinal tract has a myriad of  functions, such as digestion, absorption and excretion, as well as the synthesis of an array of  hormones, growth factors and cytokines. In addi tion, a complex enteric nervous system has evolved to control its function and communicate with the central and peripheral nervous systems. Finally , as the gastrointestinal tract contains the largest sources of  foreign antigens to which the body is exposed, it houses well-developed arms of both the innate and acquired immune systems. Therefore, it is not surprising that malfunction or infection of  this complex organ results in a wide spectrum of  pathology . However, its importance in disease pathogenesis is matched only by its inaccessibility to traditional examination. Few discoveries in medicine have contributed more to the practice of  gastroenterology than the development of diagnostic and therapeutic endoscopy . Although spectacular advances in radiology have occurr ed recently with the intro duction of  multislice spiral computed tomography (CT) and magnetic resonance imaging (MRI), the ability to take tar geted mucosal biopsies remains a unique strength of  endos copy . Historically , radiological techniques were required to image areas of jejunum and ileum inaccessible to the stan dard endoscope; ho wever, the introduction of both capsule endoscopy and single-/double-balloon enteroscopy allows both diagnostic and therapeutic access to the entire gastro intestinal tract. Image enhancement with techniques such as chromoendoscopy , magnifica tion endoscopy and narrow band imaging allows increased resolution a t the mucosal level and increases diagnostic yield. Endoscopic ultrasound (EUS) can examine all layers of the intestinal wall as well as extraintestinal structures. Finally , experimental techniques such as confocal Harold Horace Hopkins , 1918–1994, Professor of  Applied Optics, The University of  Reading, Reading, UK. laser endomicroscopy give resolution at a level compatible with standard histology . The advances in the diagnostic accuracy of endoscopy lend themselves to disease surveillance for specific patient groups as well as population screening for gastrointesti - - nal malignancy . Likewise, there has been a rapid expansion in the therapeutic capability of endoscopy with both luminal and extraintestinal surgery being performed via endoscopic access. As in all areas of interventional practice, competent endoscopists must match a thorough grounding in anatomy and physiology with a clear understanding of  the capabilities and limitations of  the rapidly advancing techniques a vailable. Perhaps most importantly they must appreciate all aspects of patient care, including preprocedural management, commu - nication before and during the procedure and the manage - ment of  endoscopic complications. This chapter aims to guide the reader through these areas in addition to introducing the breadth of  procedur es that are currently performed. - 

The indications for diagnostic and therapeutic endoscopic
•
procedures including endoscopic ultrasound
The recognition and management of complications
•
Novel techniques for endoscoping the small bowel
•
Advances in diagnostic ability
•

# Learning objectives

Learning objectives

To gain an understanding of: The role of endoscopy as a diagnostic and therapeutic • tool The basic organisation of an endoscopy unit and its • equipment Consent and safe sedation • Special situations: the key points in managing endoscopy • in at-risk patients Learning objectives

To gain an understanding of: The role of endoscopy as a diagnostic and therapeutic • tool The basic organisation of an endoscopy unit and its • equipment Consent and safe sedation • Special situations: the key points in managing endoscopy • in at-risk patients Learning objectives

To gain an understanding of: The role of endoscopy as a diagnostic and therapeutic • tool The basic organisation of an endoscopy unit and its • equipment Consent and safe sedation • Special situations: the key points in managing endoscopy • in at-risk patients

# Optical diagnosis and image enhancement

Optical diagnosis and image enhancement

With the assistance of  advanced imaging techniques, endosco - pists are now able to characterise colorectal polyps with high diagnostic accuracy . This begins with a white light assessment: polyps larger than 2 /uni00A0 cm with a large sessile component or a depressed region have the highest risk of  containing cancer. Application of  advanced imaging tec hniques can improve diagnostic accuracy further ( Figure 9.15 ). Dye-based chromoendoscopy involves topical application of  stains or pigments to improve mucosal characterisation. Several agents have been described, which can broadly be cate - gorised as absorptiv e (vital) stains, such as methylene blue, and contrast (reactive) stains, such as crystal violet and indigo car - mine. These highlight the mucosal pits, which can aid optical diagnosis; di ff erent lesions demonstrate specific pit patterns. Dye c hromoendoscopy is still widely used and remains the recommended method of  dysplasia detection in inflammatory bowel disease . - Narrow band imaging (NBI; Olympus) relies on opti - cal filter technology that radically improves the visibility of 

(a)
and,

capillaries, veins and other subtle tissue structures by optimis ing the absorbance and scattering characteristics of  light. NBI uses two discrete bands of  light: one blue at 415 /uni00A0 nm and one green at 540 /uni00A0 nm. Narrow band blue light displays superficial capillary netw orks, whereas green light displays subepithelial vessels; when combined they o ff er an extremely high contrast image of  the tissue surface. Similar modalities such as i-Scan (Pentax) and Blue Light Imaging (BLI; Fujifilm) are also avail able. Dye-based and digital enhancement, particularly when combined with magnification endoscopy , can di ff erentiate between hyperplastic, serrated, adenomatous and malignant pathology . Combining this with a detailed white light assess - ment allows endoscopists to determine endoscopic resectabil - ity , avoiding more extensive surgery in some cases. 

(b)
(c)
Figure 9.15
Endoscopic diagnostic accuracy can be improved by
novel endoscopic techniques. This duodenal adenoma can be seen
with conventional white light
(a)
(arrow), but its full extent is more
clearly delineated using narrow band imaging
(b)
or chromoendos
copy with indigo carmine
(c)
.
(b)
Figure 9.16
Colonoscopy is the most appropriate investigation to
detect colonic polyps
(a)
, which can be removed by snare polypec
-
tomy during the same procedure, leaving a clean polyp base
(b)
.

Optical diagnosis and image enhancement

With the assistance of  advanced imaging techniques, endosco - pists are now able to characterise colorectal polyps with high diagnostic accuracy . This begins with a white light assessment: polyps larger than 2 /uni00A0 cm with a large sessile component or a depressed region have the highest risk of  containing cancer. Application of  advanced imaging tec hniques can improve diagnostic accuracy further ( Figure 9.15 ). Dye-based chromoendoscopy involves topical application of  stains or pigments to improve mucosal characterisation. Several agents have been described, which can broadly be cate - gorised as absorptiv e (vital) stains, such as methylene blue, and contrast (reactive) stains, such as crystal violet and indigo car - mine. These highlight the mucosal pits, which can aid optical diagnosis; di ff erent lesions demonstrate specific pit patterns. Dye c hromoendoscopy is still widely used and remains the recommended method of  dysplasia detection in inflammatory bowel disease . - Narrow band imaging (NBI; Olympus) relies on opti - cal filter technology that radically improves the visibility of 

(a)
and,

capillaries, veins and other subtle tissue structures by optimis ing the absorbance and scattering characteristics of  light. NBI uses two discrete bands of  light: one blue at 415 /uni00A0 nm and one green at 540 /uni00A0 nm. Narrow band blue light displays superficial capillary netw orks, whereas green light displays subepithelial vessels; when combined they o ff er an extremely high contrast image of  the tissue surface. Similar modalities such as i-Scan (Pentax) and Blue Light Imaging (BLI; Fujifilm) are also avail able. Dye-based and digital enhancement, particularly when combined with magnification endoscopy , can di ff erentiate between hyperplastic, serrated, adenomatous and malignant pathology . Combining this with a detailed white light assess - ment allows endoscopists to determine endoscopic resectabil - ity , avoiding more extensive surgery in some cases. 

(b)
(c)
Figure 9.15
Endoscopic diagnostic accuracy can be improved by
novel endoscopic techniques. This duodenal adenoma can be seen
with conventional white light
(a)
(arrow), but its full extent is more
clearly delineated using narrow band imaging
(b)
or chromoendos
copy with indigo carmine
(c)
.
(b)
Figure 9.16
Colonoscopy is the most appropriate investigation to
detect colonic polyps
(a)
, which can be removed by snare polypec
-
tomy during the same procedure, leaving a clean polyp base
(b)
.

Optical diagnosis and image enhancement

With the assistance of  advanced imaging techniques, endosco - pists are now able to characterise colorectal polyps with high diagnostic accuracy . This begins with a white light assessment: polyps larger than 2 /uni00A0 cm with a large sessile component or a depressed region have the highest risk of  containing cancer. Application of  advanced imaging tec hniques can improve diagnostic accuracy further ( Figure 9.15 ). Dye-based chromoendoscopy involves topical application of  stains or pigments to improve mucosal characterisation. Several agents have been described, which can broadly be cate - gorised as absorptiv e (vital) stains, such as methylene blue, and contrast (reactive) stains, such as crystal violet and indigo car - mine. These highlight the mucosal pits, which can aid optical diagnosis; di ff erent lesions demonstrate specific pit patterns. Dye c hromoendoscopy is still widely used and remains the recommended method of  dysplasia detection in inflammatory bowel disease . - Narrow band imaging (NBI; Olympus) relies on opti - cal filter technology that radically improves the visibility of 

(a)
and,

capillaries, veins and other subtle tissue structures by optimis ing the absorbance and scattering characteristics of  light. NBI uses two discrete bands of  light: one blue at 415 /uni00A0 nm and one green at 540 /uni00A0 nm. Narrow band blue light displays superficial capillary netw orks, whereas green light displays subepithelial vessels; when combined they o ff er an extremely high contrast image of  the tissue surface. Similar modalities such as i-Scan (Pentax) and Blue Light Imaging (BLI; Fujifilm) are also avail able. Dye-based and digital enhancement, particularly when combined with magnification endoscopy , can di ff erentiate between hyperplastic, serrated, adenomatous and malignant pathology . Combining this with a detailed white light assess - ment allows endoscopists to determine endoscopic resectabil - ity , avoiding more extensive surgery in some cases. 

(b)
(c)
Figure 9.15
Endoscopic diagnostic accuracy can be improved by
novel endoscopic techniques. This duodenal adenoma can be seen
with conventional white light
(a)
(arrow), but its full extent is more
clearly delineated using narrow band imaging
(b)
or chromoendos
copy with indigo carmine
(c)
.
(b)
Figure 9.16
Colonoscopy is the most appropriate investigation to
detect colonic polyps
(a)
, which can be removed by snare polypec
-
tomy during the same procedure, leaving a clean polyp base
(b)
.

# SAFE SEDATION

SAFE SEDATION

If  performed competently the majority of  diagnostic endos - copies and colonoscopies can be performed without sedation or with pharyngeal anaesthesia alone. However, therapeutic - procedures may cause pain and patients are often anxious; thus, in most countries seda tion and analgesia are o ff ered - to achieve a state of conscious sedation (not anaesthesia). Medication-induced respiratory depression in elderly patients or those with comorbidities is the greatest cause of endoscopy- essential. The involvement of  anaesthetists to advise on appropriate protocols is recommended. Endoscopy in certain situations (particularly paediatric endoscopy) requires a general anaesthetic /uni00A0 – /uni00A0 this should only be undertaken by appropriately trained sta ff with adequate equipment available. Summary box 9.3 Sedation in endoscopy /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF 

Pharyngeal anaesthesia may increase the risk of aspiration in
more heavily sedated patients
Comorbidities must be identi
/f_i
ed so that sedation can be
individualised
All sedated patients require secure intravenous access
Benzodiazepines reach their maximum effect 9–20
/uni00A0
minutes
after administration
/uni00A0
–
/uni00A0
doses should be titrated carefully,
particularly in the elderly or those with comorbidities
Coadministration of opiates and benzodiazepines has a
synergistic effect; opiates should be given
/f_i
rst and doses need
to be reduced
The use of supplementary oxygen is essential in all sedated
patients
Sedated patients require pulse oximetry to monitor oxygen
saturation; high-risk patients or those undergoing high-risk
procedures also require blood pressure and electrocardiogram
monitoring
A trained assistant should be responsible for patient monitoring
throughout the procedure
Resuscitation equipment and sedation reversal agents must be
readily available
The use of anaesthetic agents such as propofol for complex
procedures requires specialist training
The half-life of benzodiazepines is 4–24
/uni00A0
hours
/uni00A0
–
/uni00A0
appropriate
recovery and monitoring is essential. Postprocedural
consultations may not be remembered, and patients must be
advised not to drink alcohol or drive for 24
/uni00A0
hours

SAFE SEDATION

If  performed competently the majority of  diagnostic endos - copies and colonoscopies can be performed without sedation or with pharyngeal anaesthesia alone. However, therapeutic - procedures may cause pain and patients are often anxious; thus, in most countries seda tion and analgesia are o ff ered - to achieve a state of conscious sedation (not anaesthesia). Medication-induced respiratory depression in elderly patients or those with comorbidities is the greatest cause of endoscopy- essential. The involvement of  anaesthetists to advise on appropriate protocols is recommended. Endoscopy in certain situations (particularly paediatric endoscopy) requires a general anaesthetic /uni00A0 – /uni00A0 this should only be undertaken by appropriately trained sta ff with adequate equipment available. Summary box 9.3 Sedation in endoscopy /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF 

Pharyngeal anaesthesia may increase the risk of aspiration in
more heavily sedated patients
Comorbidities must be identi
/f_i
ed so that sedation can be
individualised
All sedated patients require secure intravenous access
Benzodiazepines reach their maximum effect 9–20
/uni00A0
minutes
after administration
/uni00A0
–
/uni00A0
doses should be titrated carefully,
particularly in the elderly or those with comorbidities
Coadministration of opiates and benzodiazepines has a
synergistic effect; opiates should be given
/f_i
rst and doses need
to be reduced
The use of supplementary oxygen is essential in all sedated
patients
Sedated patients require pulse oximetry to monitor oxygen
saturation; high-risk patients or those undergoing high-risk
procedures also require blood pressure and electrocardiogram
monitoring
A trained assistant should be responsible for patient monitoring
throughout the procedure
Resuscitation equipment and sedation reversal agents must be
readily available
The use of anaesthetic agents such as propofol for complex
procedures requires specialist training
The half-life of benzodiazepines is 4–24
/uni00A0
hours
/uni00A0
–
/uni00A0
appropriate
recovery and monitoring is essential. Postprocedural
consultations may not be remembered, and patients must be
advised not to drink alcohol or drive for 24
/uni00A0
hours

SAFE SEDATION

If  performed competently the majority of  diagnostic endos - copies and colonoscopies can be performed without sedation or with pharyngeal anaesthesia alone. However, therapeutic - procedures may cause pain and patients are often anxious; thus, in most countries seda tion and analgesia are o ff ered - to achieve a state of conscious sedation (not anaesthesia). Medication-induced respiratory depression in elderly patients or those with comorbidities is the greatest cause of endoscopy- essential. The involvement of  anaesthetists to advise on appropriate protocols is recommended. Endoscopy in certain situations (particularly paediatric endoscopy) requires a general anaesthetic /uni00A0 – /uni00A0 this should only be undertaken by appropriately trained sta ff with adequate equipment available. Summary box 9.3 Sedation in endoscopy /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF 

Pharyngeal anaesthesia may increase the risk of aspiration in
more heavily sedated patients
Comorbidities must be identi
/f_i
ed so that sedation can be
individualised
All sedated patients require secure intravenous access
Benzodiazepines reach their maximum effect 9–20
/uni00A0
minutes
after administration
/uni00A0
–
/uni00A0
doses should be titrated carefully,
particularly in the elderly or those with comorbidities
Coadministration of opiates and benzodiazepines has a
synergistic effect; opiates should be given
/f_i
rst and doses need
to be reduced
The use of supplementary oxygen is essential in all sedated
patients
Sedated patients require pulse oximetry to monitor oxygen
saturation; high-risk patients or those undergoing high-risk
procedures also require blood pressure and electrocardiogram
monitoring
A trained assistant should be responsible for patient monitoring
throughout the procedure
Resuscitation equipment and sedation reversal agents must be
readily available
The use of anaesthetic agents such as propofol for complex
procedures requires specialist training
The half-life of benzodiazepines is 4–24
/uni00A0
hours
/uni00A0
–
/uni00A0
appropriate
recovery and monitoring is essential. Postprocedural
consultations may not be remembered, and patients must be
advised not to drink alcohol or drive for 24
/uni00A0
hours

# Single- double-balloon enteroscopy

Single-/double-balloon enteroscopy

This technique allows the direct visualisation of  and ther - apeutic intervention for the entire small bowel and may be attempted via either the oral or rectal route. Double-balloon enteroscopy involves the use of  a thin enteroscope and an overtube, which are both fitted with a balloon. The procedure is usually carried out under general anaesthesia but may be undertaken with the use of  conscious sedation. The enteroscope and overtube are inserted through either the mouth or anus and steered to the proximal duodenum/ terminal ileum in the conventional manner. Following this the endoscope is advanced a small distance in front of  the overtube and the balloon at the end is inflated. Using the assistance of  friction at the interface between the enteroscope and intestinal wall, the small bowel is accordioned back to the overtube. The overtube balloon is then deployed and the enteroscope balloon is deflated. The process is then continued until the entire small bowel is visualised ( Figure 9.12 ). In single-balloon enteroscopy , devel oped more recently , an enteroscope and overtube are used, but only the overtube has a balloon attached. A full range of therapeutics including diagnostic biopsy , polypectomy , APC and stent insertion are a vailable for balloon enteroscopy . Some experts advocate routine capsule endoscopy before balloon enteroscopy in an attempt to localise any lesions and plan whether oral or rectal access is more appropriate. The Summary box 9.6 Current established indications for single-/double- balloon endoscopy /uni25CF /uni25CF /uni25CF indications for single-/double-balloon endoscopy are given in Summary box 9.6 . 

(b)
(d)
Battery
Optical dome
Lens
Transmitter
Light-emitting diode (LED)
Antenna
Processor
Bleeding from the gastrointestinal tract of obscure cause
Iron de
/f_i
ciency anaemia with normal colonoscopy and
gastroscopy
Visualisation of and therapeutic intervention for abnormalities
seen on traditional small bowel imaging/capsule endoscopy
Figure 9.11
Complete diagnostic visuali
-
sation of the small bowel can be achieved
with capsule endoscopy
(a)
. The structure
of the capsule is shown in
(b)
. Clear muco
-
sal pictures can be achieved, here showing
angioectasias (arrow)
(c)
and small bowel
.
Crohn’s disease
(d)

Single-/double-balloon enteroscopy

This technique allows the direct visualisation of  and ther - apeutic intervention for the entire small bowel and may be attempted via either the oral or rectal route. Double-balloon enteroscopy involves the use of  a thin enteroscope and an overtube, which are both fitted with a balloon. The procedure is usually carried out under general anaesthesia but may be undertaken with the use of  conscious sedation. The enteroscope and overtube are inserted through either the mouth or anus and steered to the proximal duodenum/ terminal ileum in the conventional manner. Following this the endoscope is advanced a small distance in front of  the overtube and the balloon at the end is inflated. Using the assistance of  friction at the interface between the enteroscope and intestinal wall, the small bowel is accordioned back to the overtube. The overtube balloon is then deployed and the enteroscope balloon is deflated. The process is then continued until the entire small bowel is visualised ( Figure 9.12 ). In single-balloon enteroscopy , devel oped more recently , an enteroscope and overtube are used, but only the overtube has a balloon attached. A full range of therapeutics including diagnostic biopsy , polypectomy , APC and stent insertion are a vailable for balloon enteroscopy . Some experts advocate routine capsule endoscopy before balloon enteroscopy in an attempt to localise any lesions and plan whether oral or rectal access is more appropriate. The Summary box 9.6 Current established indications for single-/double- balloon endoscopy /uni25CF /uni25CF /uni25CF indications for single-/double-balloon endoscopy are given in Summary box 9.6 . 

(b)
(d)
Battery
Optical dome
Lens
Transmitter
Light-emitting diode (LED)
Antenna
Processor
Bleeding from the gastrointestinal tract of obscure cause
Iron de
/f_i
ciency anaemia with normal colonoscopy and
gastroscopy
Visualisation of and therapeutic intervention for abnormalities
seen on traditional small bowel imaging/capsule endoscopy
Figure 9.11
Complete diagnostic visuali
-
sation of the small bowel can be achieved
with capsule endoscopy
(a)
. The structure
of the capsule is shown in
(b)
. Clear muco
-
sal pictures can be achieved, here showing
angioectasias (arrow)
(c)
and small bowel
.
Crohn’s disease
(d)

Single-/double-balloon enteroscopy

This technique allows the direct visualisation of  and ther - apeutic intervention for the entire small bowel and may be attempted via either the oral or rectal route. Double-balloon enteroscopy involves the use of  a thin enteroscope and an overtube, which are both fitted with a balloon. The procedure is usually carried out under general anaesthesia but may be undertaken with the use of  conscious sedation. The enteroscope and overtube are inserted through either the mouth or anus and steered to the proximal duodenum/ terminal ileum in the conventional manner. Following this the endoscope is advanced a small distance in front of  the overtube and the balloon at the end is inflated. Using the assistance of  friction at the interface between the enteroscope and intestinal wall, the small bowel is accordioned back to the overtube. The overtube balloon is then deployed and the enteroscope balloon is deflated. The process is then continued until the entire small bowel is visualised ( Figure 9.12 ). In single-balloon enteroscopy , devel oped more recently , an enteroscope and overtube are used, but only the overtube has a balloon attached. A full range of therapeutics including diagnostic biopsy , polypectomy , APC and stent insertion are a vailable for balloon enteroscopy . Some experts advocate routine capsule endoscopy before balloon enteroscopy in an attempt to localise any lesions and plan whether oral or rectal access is more appropriate. The Summary box 9.6 Current established indications for single-/double- balloon endoscopy /uni25CF /uni25CF /uni25CF indications for single-/double-balloon endoscopy are given in Summary box 9.6 . 

(b)
(d)
Battery
Optical dome
Lens
Transmitter
Light-emitting diode (LED)
Antenna
Processor
Bleeding from the gastrointestinal tract of obscure cause
Iron de
/f_i
ciency anaemia with normal colonoscopy and
gastroscopy
Visualisation of and therapeutic intervention for abnormalities
seen on traditional small bowel imaging/capsule endoscopy
Figure 9.11
Complete diagnostic visuali
-
sation of the small bowel can be achieved
with capsule endoscopy
(a)
. The structure
of the capsule is shown in
(b)
. Clear muco
-
sal pictures can be achieved, here showing
angioectasias (arrow)
(c)
and small bowel
.
Crohn’s disease
(d)

# THE MODERN ENDOSCOPY UNIT Organisation

THE MODERN ENDOSCOPY UNIT Organisation

A well-designed endoscopy unit sta ff ed by trained endoscopy nurses and dedicated administrative sta ff is essential to support good endoscopic practice and training. Clinical governance with regular appraisal and assessment of  performance should be embedded within the unit’s philosophy . Endoscopist train - ing demands particular attention, with a transparent process of skills- and theory-based education centred on practical experi - - ence and dedicated training courses. Experienced supervision of  all trainees is essential until competency has been obtained and assessed by an appropriately v alidated technique, such as ). dir ect observation of  practical skills (DOPS) and review of procedure logbooks. All endoscopists should record diagnostic - and therapeutic procedure numbers and markers of  compe - tency such as colonoscopy completion rates, polyp detection rates, mean sedation use and complication rates. Central to this ovides outcome is an e ffi cient data management system that pr analysis for all aspects of  endoscopy , including adherence to guidelines, near misses, patient satisfaction, decontamination processes and scope tracking, as well as the more obvious completion and complication rates. In the UK the Joint Advisory Group (JAG) provides guid - ance for endoscopist competence assessment and operates a certification system of individual endoscopic competencies, based on procedure numbers, key performance indicators (e.g . caecal intubation rate, adenoma detection, sedation levels, complications), course attendance and peer assessment. THE MODERN ENDOSCOPY UNIT Organisation

A well-designed endoscopy unit sta ff ed by trained endoscopy nurses and dedicated administrative sta ff is essential to support good endoscopic practice and training. Clinical governance with regular appraisal and assessment of  performance should be embedded within the unit’s philosophy . Endoscopist train - ing demands particular attention, with a transparent process of skills- and theory-based education centred on practical experi - - ence and dedicated training courses. Experienced supervision of  all trainees is essential until competency has been obtained and assessed by an appropriately v alidated technique, such as ). dir ect observation of  practical skills (DOPS) and review of procedure logbooks. All endoscopists should record diagnostic - and therapeutic procedure numbers and markers of  compe - tency such as colonoscopy completion rates, polyp detection rates, mean sedation use and complication rates. Central to this ovides outcome is an e ffi cient data management system that pr analysis for all aspects of  endoscopy , including adherence to guidelines, near misses, patient satisfaction, decontamination processes and scope tracking, as well as the more obvious completion and complication rates. In the UK the Joint Advisory Group (JAG) provides guid - ance for endoscopist competence assessment and operates a certification system of individual endoscopic competencies, based on procedure numbers, key performance indicators (e.g . caecal intubation rate, adenoma detection, sedation levels, complications), course attendance and peer assessment. THE MODERN ENDOSCOPY UNIT Organisation

A well-designed endoscopy unit sta ff ed by trained endoscopy nurses and dedicated administrative sta ff is essential to support good endoscopic practice and training. Clinical governance with regular appraisal and assessment of  performance should be embedded within the unit’s philosophy . Endoscopist train - ing demands particular attention, with a transparent process of skills- and theory-based education centred on practical experi - - ence and dedicated training courses. Experienced supervision of  all trainees is essential until competency has been obtained and assessed by an appropriately v alidated technique, such as ). dir ect observation of  practical skills (DOPS) and review of procedure logbooks. All endoscopists should record diagnostic - and therapeutic procedure numbers and markers of  compe - tency such as colonoscopy completion rates, polyp detection rates, mean sedation use and complication rates. Central to this ovides outcome is an e ffi cient data management system that pr analysis for all aspects of  endoscopy , including adherence to guidelines, near misses, patient satisfaction, decontamination processes and scope tracking, as well as the more obvious completion and complication rates. In the UK the Joint Advisory Group (JAG) provides guid - ance for endoscopist competence assessment and operates a certification system of individual endoscopic competencies, based on procedure numbers, key performance indicators (e.g . caecal intubation rate, adenoma detection, sedation levels, complications), course attendance and peer assessment.

# Therapeutic colonoscopy

Therapeutic colonoscopy

The most common therapeutic procedure performed at colo - noscopy is resection of  colonic polyps ( Figure 9.16 ). Retrieved specimens can be assessed for risk factors for neoplastic progres - - sion and an appropriate surveillance strategy determined (https://www .bsg.org.uk/wp-content/uploads/2019/09/201. full_.pdf). Non-pedunculated polyps up to 15 /uni00A0 mm should be removed by cheese wiring with a dedicated ‘cold’ snare. Stalked polyps can be resected using ‘hot’ snare polypectomy . thermy is used with either a ‘cut’, ‘coagulation’ or a Here, dia blended current. Postpolypectomy bleeding can be prevented - by preinjection of  the stalk with adrenaline, or with application ® . of  endoclips or an Endoloop 

-

Non-pedunculated polyps of  between 10 and 19 /uni00A0 mm can be removed en bloc by EMR, which involves lifting the polyp from the muscularis propria with a submucosal injectate to prevent iatrogenic perforation ( Figure 9.17 ). Lesions >20 /uni00A0 mm can be removed with piecemeal EMR (pEMR); on completion, thermal ablation (with either APC or coagulation) is applied to the edge of  the resection site to prevent adenoma recurrence. , which is typically performed An alternative to pEMR is ESD with a knife rather than a snare. This technique involves the injection of  a submucosal solution, followed by a circumfer ential incision and submucosal dissection, with coagulation of blood vessels that are encountered. This enables an en bloc resection of  large polyps and superficial submucosal cancers. Although technically challenging with a steep learning curve, benefits include a more accurate histopathological assessment and lower adenoma recurrence rates. APC and alternative thermal therapies such as heater probes are also used in the treatment of  symptomatic angioec - tasias of the colon ( Figure 9.18 ). Laser photocoagulation may be used to debulk colonic tumours not suitable for resection. As with benign oesophageal strictures, TTS balloons can be - used to dilate short (<5 /uni00A0 cm) colonic strictures. The dilata - tion of  sur gical anastomoses gives the most durable benefit as inflammatory strictures tend to recur even if  intramucosal steroids are injected at the time of the dilatation. Finally , the colonoscopic placement of  self-expanding metal stents may provide excellent palliation of  inoperable malignant strictures ( Figure 9.19 ) and may also play an invaluable role in decom - pressing an obstructed colon to allow planned as opposed to emergency surgery . 

(c)
Figure 9.17
Large sessile polyps
(a)
can be removed by endoscopic muco
-
sal resection. First the polyp is raised
on a bed of injected saline containing
dye
(b)
. This ensures that there is no
submucosal invasion and protects
from transmural perforation. A snare is
closed around the polyp
(c)
, which is
then resected leaving a clean excision
base
(d)
.
Figure 9.18
A large angioectasia of the colon. If this results in
symptomatic anaemia, it should be obliterated with argon plasma
coagulation.
(d)

Therapeutic colonoscopy

The most common therapeutic procedure performed at colo - noscopy is resection of  colonic polyps ( Figure 9.16 ). Retrieved specimens can be assessed for risk factors for neoplastic progres - - sion and an appropriate surveillance strategy determined (https://www .bsg.org.uk/wp-content/uploads/2019/09/201. full_.pdf). Non-pedunculated polyps up to 15 /uni00A0 mm should be removed by cheese wiring with a dedicated ‘cold’ snare. Stalked polyps can be resected using ‘hot’ snare polypectomy . thermy is used with either a ‘cut’, ‘coagulation’ or a Here, dia blended current. Postpolypectomy bleeding can be prevented - by preinjection of  the stalk with adrenaline, or with application ® . of  endoclips or an Endoloop 

-

Non-pedunculated polyps of  between 10 and 19 /uni00A0 mm can be removed en bloc by EMR, which involves lifting the polyp from the muscularis propria with a submucosal injectate to prevent iatrogenic perforation ( Figure 9.17 ). Lesions >20 /uni00A0 mm can be removed with piecemeal EMR (pEMR); on completion, thermal ablation (with either APC or coagulation) is applied to the edge of  the resection site to prevent adenoma recurrence. , which is typically performed An alternative to pEMR is ESD with a knife rather than a snare. This technique involves the injection of  a submucosal solution, followed by a circumfer ential incision and submucosal dissection, with coagulation of blood vessels that are encountered. This enables an en bloc resection of  large polyps and superficial submucosal cancers. Although technically challenging with a steep learning curve, benefits include a more accurate histopathological assessment and lower adenoma recurrence rates. APC and alternative thermal therapies such as heater probes are also used in the treatment of  symptomatic angioec - tasias of the colon ( Figure 9.18 ). Laser photocoagulation may be used to debulk colonic tumours not suitable for resection. As with benign oesophageal strictures, TTS balloons can be - used to dilate short (<5 /uni00A0 cm) colonic strictures. The dilata - tion of  sur gical anastomoses gives the most durable benefit as inflammatory strictures tend to recur even if  intramucosal steroids are injected at the time of the dilatation. Finally , the colonoscopic placement of  self-expanding metal stents may provide excellent palliation of  inoperable malignant strictures ( Figure 9.19 ) and may also play an invaluable role in decom - pressing an obstructed colon to allow planned as opposed to emergency surgery . 

(c)
Figure 9.17
Large sessile polyps
(a)
can be removed by endoscopic muco
-
sal resection. First the polyp is raised
on a bed of injected saline containing
dye
(b)
. This ensures that there is no
submucosal invasion and protects
from transmural perforation. A snare is
closed around the polyp
(c)
, which is
then resected leaving a clean excision
base
(d)
.
Figure 9.18
A large angioectasia of the colon. If this results in
symptomatic anaemia, it should be obliterated with argon plasma
coagulation.
(d)

Therapeutic colonoscopy

The most common therapeutic procedure performed at colo - noscopy is resection of  colonic polyps ( Figure 9.16 ). Retrieved specimens can be assessed for risk factors for neoplastic progres - - sion and an appropriate surveillance strategy determined (https://www .bsg.org.uk/wp-content/uploads/2019/09/201. full_.pdf). Non-pedunculated polyps up to 15 /uni00A0 mm should be removed by cheese wiring with a dedicated ‘cold’ snare. Stalked polyps can be resected using ‘hot’ snare polypectomy . thermy is used with either a ‘cut’, ‘coagulation’ or a Here, dia blended current. Postpolypectomy bleeding can be prevented - by preinjection of  the stalk with adrenaline, or with application ® . of  endoclips or an Endoloop 

-

Non-pedunculated polyps of  between 10 and 19 /uni00A0 mm can be removed en bloc by EMR, which involves lifting the polyp from the muscularis propria with a submucosal injectate to prevent iatrogenic perforation ( Figure 9.17 ). Lesions >20 /uni00A0 mm can be removed with piecemeal EMR (pEMR); on completion, thermal ablation (with either APC or coagulation) is applied to the edge of  the resection site to prevent adenoma recurrence. , which is typically performed An alternative to pEMR is ESD with a knife rather than a snare. This technique involves the injection of  a submucosal solution, followed by a circumfer ential incision and submucosal dissection, with coagulation of blood vessels that are encountered. This enables an en bloc resection of  large polyps and superficial submucosal cancers. Although technically challenging with a steep learning curve, benefits include a more accurate histopathological assessment and lower adenoma recurrence rates. APC and alternative thermal therapies such as heater probes are also used in the treatment of  symptomatic angioec - tasias of the colon ( Figure 9.18 ). Laser photocoagulation may be used to debulk colonic tumours not suitable for resection. As with benign oesophageal strictures, TTS balloons can be - used to dilate short (<5 /uni00A0 cm) colonic strictures. The dilata - tion of  sur gical anastomoses gives the most durable benefit as inflammatory strictures tend to recur even if  intramucosal steroids are injected at the time of the dilatation. Finally , the colonoscopic placement of  self-expanding metal stents may provide excellent palliation of  inoperable malignant strictures ( Figure 9.19 ) and may also play an invaluable role in decom - pressing an obstructed colon to allow planned as opposed to emergency surgery . 

(c)
Figure 9.17
Large sessile polyps
(a)
can be removed by endoscopic muco
-
sal resection. First the polyp is raised
on a bed of injected saline containing
dye
(b)
. This ensures that there is no
submucosal invasion and protects
from transmural perforation. A snare is
closed around the polyp
(c)
, which is
then resected leaving a clean excision
base
(d)
.
Figure 9.18
A large angioectasia of the colon. If this results in
symptomatic anaemia, it should be obliterated with argon plasma
coagulation.
(d)

# Therapeutic endoscopic retrograde cholangiopancrea

Therapeutic endoscopic retrograde cholangiopancreatography

It is essential to ensure that patients have appropriate assess - ment prior to therapeutic ERCP , which is associated with a significant morbidity and occasional mortality . All patients require routine blood screening including a clotting screen. Both cardiac and oxygen saturation monitoring are required during the pr ocedure because of the high level of sedation that is often required. The most common indication for therapeutic ERCP is relief  of  biliary obstruction due to gallstone disease or benign or malignant biliary strictures. The preprocedural diagnosis can be confirmed by contrast injection, which will clearly di ff erentiate the filling defects associated with gallstones and the luminal narrowing of  a stricture. If  there is likely to be a delay in relieving an obstructed system, percutaneous drainage may be required. The cornerstone of gallstone retrieval is an adequate biliary sphincterotomy , which is normally performed over a well-positioned guidewire using a sphincterotome connected to an electrosurgical unit. Most g allstones <1 /uni00A0 cm in diame ter will pass spontaneously in the days and weeks following a sphincterotomy , but most endoscopists prefer to ensure duct clearance at the initial procedure to reduce the risk of impaction, cholangitis or pancreatitis. This can be achieved by trawling the duct using a balloon catheter or by extraction using a wire basket. If  standard techniques fail, large or awk - wardly placed stones can be crushed using mechanical litho - tripsy . If  adequate stone extraction cannot be achieved at the initial ERCP it is imperative to ensure biliary drainage with the placement of  a removable plastic stent while alternative options are considered. T hese include surgery , endoscopically directed shockwaves under direct choledochoscopic vision and extracorporeal shockwave lithotripsy with subsequent ERCP - to remove stone fragments. 

Endoscope balloon
deflated
4
Figure
9.12
The technique of
double-balloon enteroscopy is per
-
formed with an adapted enteroscope
Overtube advanced along
and overtube, both of which have
endoscope. Overtube balloon
in
/f_l
atable balloons at their tip.
inflated
(a)
Figure 9.13
During endoscopic retrograde
cholangiopancreatography a side-viewing duo
-
denoscope is positioned opposite the papilla,
which can then be cannulated using either a
catheter or a guidewire
(a)
. Contrast is injected
to achieve a cholangiogram
(b)
.
Endoscope advanced
Endoscope balloon inflated.
deeper into intestine
Overtube balloon deflated
6
5
Endoscope–overtube pulled Endoscope balloon deflated.
back to straighten path Endoscope advanced again
through intestine
(b)

similar to those used in angioplasty inserted over a guidewire under fluoroscopic control. It is traditional to insert a tempo rary plastic stent to maintain drainage as several attempts at dilatation may be required. Self-expanding metal stents are most commonly used for the palliation of  malignant biliary obstruction and are also normally inserted after a modest sphincterotomy . Corr ect stent placement can normally be con firmed by a flow of  bile after release and by the presence of  air in the biliary tree on follow-up plain abdominal radiographs. Stent malfunction, associated with recurrent or persistent bio chemical cholestasis, may be due to poor initial stent position, stent migra tion, blockage with blood clot or debris or tumour ingrowth. A repeat procedure is required to assess the cause, which can usually be r emedied by the insertion of  a second stent through the original one. In addition to the standard techniques discussed above, ERCP is also used for pancreatic disease and the assessment of  biliary dysmotility (sphincter of  Oddi dysfunction) using manometr y in specialist centres. Indications include pancre atic stone extraction, the dilatation of  pancreatic duct stric tures and the transgastric drainage of  pancreatic pseudocysts. To minimise the risks of  subsequent pancreatitis, pancreatic sphincterotomy is most safely performed after the placement of  a temporary pancreatic stent to prev ent stasis within the pancreatic duct. Visualisation and sampling of  biliary lesions is becom ing easier and more e ff ective with the development of  newer through-the-duodenoscope cholangioscopes that allow direct visualisation and instrumentation of the biliary and pancrea ducts. Therapeutic endoscopic retrograde cholangiopancreatography

It is essential to ensure that patients have appropriate assess - ment prior to therapeutic ERCP , which is associated with a significant morbidity and occasional mortality . All patients require routine blood screening including a clotting screen. Both cardiac and oxygen saturation monitoring are required during the pr ocedure because of the high level of sedation that is often required. The most common indication for therapeutic ERCP is relief  of  biliary obstruction due to gallstone disease or benign or malignant biliary strictures. The preprocedural diagnosis can be confirmed by contrast injection, which will clearly di ff erentiate the filling defects associated with gallstones and the luminal narrowing of  a stricture. If  there is likely to be a delay in relieving an obstructed system, percutaneous drainage may be required. The cornerstone of gallstone retrieval is an adequate biliary sphincterotomy , which is normally performed over a well-positioned guidewire using a sphincterotome connected to an electrosurgical unit. Most g allstones <1 /uni00A0 cm in diame ter will pass spontaneously in the days and weeks following a sphincterotomy , but most endoscopists prefer to ensure duct clearance at the initial procedure to reduce the risk of impaction, cholangitis or pancreatitis. This can be achieved by trawling the duct using a balloon catheter or by extraction using a wire basket. If  standard techniques fail, large or awk - wardly placed stones can be crushed using mechanical litho - tripsy . If  adequate stone extraction cannot be achieved at the initial ERCP it is imperative to ensure biliary drainage with the placement of  a removable plastic stent while alternative options are considered. T hese include surgery , endoscopically directed shockwaves under direct choledochoscopic vision and extracorporeal shockwave lithotripsy with subsequent ERCP - to remove stone fragments. 

Endoscope balloon
deflated
4
Figure
9.12
The technique of
double-balloon enteroscopy is per
-
formed with an adapted enteroscope
Overtube advanced along
and overtube, both of which have
endoscope. Overtube balloon
in
/f_l
atable balloons at their tip.
inflated
(a)
Figure 9.13
During endoscopic retrograde
cholangiopancreatography a side-viewing duo
-
denoscope is positioned opposite the papilla,
which can then be cannulated using either a
catheter or a guidewire
(a)
. Contrast is injected
to achieve a cholangiogram
(b)
.
Endoscope advanced
Endoscope balloon inflated.
deeper into intestine
Overtube balloon deflated
6
5
Endoscope–overtube pulled Endoscope balloon deflated.
back to straighten path Endoscope advanced again
through intestine
(b)

similar to those used in angioplasty inserted over a guidewire under fluoroscopic control. It is traditional to insert a tempo rary plastic stent to maintain drainage as several attempts at dilatation may be required. Self-expanding metal stents are most commonly used for the palliation of  malignant biliary obstruction and are also normally inserted after a modest sphincterotomy . Corr ect stent placement can normally be con firmed by a flow of  bile after release and by the presence of  air in the biliary tree on follow-up plain abdominal radiographs. Stent malfunction, associated with recurrent or persistent bio chemical cholestasis, may be due to poor initial stent position, stent migra tion, blockage with blood clot or debris or tumour ingrowth. A repeat procedure is required to assess the cause, which can usually be r emedied by the insertion of  a second stent through the original one. In addition to the standard techniques discussed above, ERCP is also used for pancreatic disease and the assessment of  biliary dysmotility (sphincter of  Oddi dysfunction) using manometr y in specialist centres. Indications include pancre atic stone extraction, the dilatation of  pancreatic duct stric tures and the transgastric drainage of  pancreatic pseudocysts. To minimise the risks of  subsequent pancreatitis, pancreatic sphincterotomy is most safely performed after the placement of  a temporary pancreatic stent to prev ent stasis within the pancreatic duct. Visualisation and sampling of  biliary lesions is becom ing easier and more e ff ective with the development of  newer through-the-duodenoscope cholangioscopes that allow direct visualisation and instrumentation of the biliary and pancrea ducts.

# Therapeutic endoscopic retrograde cholangiopancreatography

Therapeutic endoscopic retrograde cholangiopancreatography

It is essential to ensure that patients have appropriate assess - ment prior to therapeutic ERCP , which is associated with a significant morbidity and occasional mortality . All patients require routine blood screening including a clotting screen. Both cardiac and oxygen saturation monitoring are required during the pr ocedure because of the high level of sedation that is often required. The most common indication for therapeutic ERCP is relief  of  biliary obstruction due to gallstone disease or benign or malignant biliary strictures. The preprocedural diagnosis can be confirmed by contrast injection, which will clearly di ff erentiate the filling defects associated with gallstones and the luminal narrowing of  a stricture. If  there is likely to be a delay in relieving an obstructed system, percutaneous drainage may be required. The cornerstone of gallstone retrieval is an adequate biliary sphincterotomy , which is normally performed over a well-positioned guidewire using a sphincterotome connected to an electrosurgical unit. Most g allstones <1 /uni00A0 cm in diame ter will pass spontaneously in the days and weeks following a sphincterotomy , but most endoscopists prefer to ensure duct clearance at the initial procedure to reduce the risk of impaction, cholangitis or pancreatitis. This can be achieved by trawling the duct using a balloon catheter or by extraction using a wire basket. If  standard techniques fail, large or awk - wardly placed stones can be crushed using mechanical litho - tripsy . If  adequate stone extraction cannot be achieved at the initial ERCP it is imperative to ensure biliary drainage with the placement of  a removable plastic stent while alternative options are considered. T hese include surgery , endoscopically directed shockwaves under direct choledochoscopic vision and extracorporeal shockwave lithotripsy with subsequent ERCP - to remove stone fragments. 

Endoscope balloon
deflated
4
Figure
9.12
The technique of
double-balloon enteroscopy is per
-
formed with an adapted enteroscope
Overtube advanced along
and overtube, both of which have
endoscope. Overtube balloon
in
/f_l
atable balloons at their tip.
inflated
(a)
Figure 9.13
During endoscopic retrograde
cholangiopancreatography a side-viewing duo
-
denoscope is positioned opposite the papilla,
which can then be cannulated using either a
catheter or a guidewire
(a)
. Contrast is injected
to achieve a cholangiogram
(b)
.
Endoscope advanced
Endoscope balloon inflated.
deeper into intestine
Overtube balloon deflated
6
5
Endoscope–overtube pulled Endoscope balloon deflated.
back to straighten path Endoscope advanced again
through intestine
(b)

similar to those used in angioplasty inserted over a guidewire under fluoroscopic control. It is traditional to insert a tempo rary plastic stent to maintain drainage as several attempts at dilatation may be required. Self-expanding metal stents are most commonly used for the palliation of  malignant biliary obstruction and are also normally inserted after a modest sphincterotomy . Corr ect stent placement can normally be con firmed by a flow of  bile after release and by the presence of  air in the biliary tree on follow-up plain abdominal radiographs. Stent malfunction, associated with recurrent or persistent bio chemical cholestasis, may be due to poor initial stent position, stent migra tion, blockage with blood clot or debris or tumour ingrowth. A repeat procedure is required to assess the cause, which can usually be r emedied by the insertion of  a second stent through the original one. In addition to the standard techniques discussed above, ERCP is also used for pancreatic disease and the assessment of  biliary dysmotility (sphincter of  Oddi dysfunction) using manometr y in specialist centres. Indications include pancre atic stone extraction, the dilatation of  pancreatic duct stric tures and the transgastric drainage of  pancreatic pseudocysts. To minimise the risks of  subsequent pancreatitis, pancreatic sphincterotomy is most safely performed after the placement of  a temporary pancreatic stent to prev ent stasis within the pancreatic duct. Visualisation and sampling of  biliary lesions is becom ing easier and more e ff ective with the development of  newer through-the-duodenoscope cholangioscopes that allow direct visualisation and instrumentation of the biliary and pancrea ducts.

# Therapeutic oesophagogastroduodenoscopy

Therapeutic oesophagogastroduodenoscopy

Appropriate patient selection and monitoring are essential to minimise complications. The most common therapeutic endo scopic procedure performed as an emergency is the control of  upper gastrointestinal haemorrhage of  any aetiology . Band ligation has replaced sclerotherap y in the management of oesophageal varices ( Figure 9.4 ), whereas sclerotherapy using thrombin-based glues can be used to control blood loss from gastric and duodenal varices. Injection therapy with adrenaline (epinephrine) coupled with a second haemostatic technique such as thermal coagula tion or endoclip application is the technique of  choice for a peptic ulcer with active bleed ing or high-risk stigmata of haemorrhage ( Figure 9.5 ). Such high-risk bleeds should be followed by 72 /uni00A0 hours of  intravenous proton pump inhibition. Chronic blood loss from angioectasia is most safely treated with APC because of  the controlled depth of  burn compared with alternative thermal tec hniques ( Figure 9.6 ) . Haemostatic powders provide a further way to arrest bleeding; these work best for di ff use bleeding or as salvage therapy . Norman Rupert Barrett , 1903–1979, sur geon, St Thomas’s Hospital, London, UK. - - Benign oesophageal and pyloric strictures may be dilated under direct vision with through-the-scope (TTS) balloon dila - tors or the more traditional guidewire-based systems such as Savary–Gilliard bougie dilators ( Figure 9.7 ) . On occasion, more di ffi cult benign strictures can be treated by the insertion of a fully covered removable stent, or with a biodegradable stent. Likewise, the non-relaxing lower oesophageal sphincter associated with achalasia can be treated by pneumatic balloon 

(a)
(b)
(c)
(d)
Figure 9.6
The classic appearance of gastric antral vascular ectasia,
which is often treated with argon plasma coagulation.
Figure 9.5
A gastric ulcer with
active bleeding
(a)
is initially
treated with adrenaline injection
to achieve haemostasis
(b)
. Two
haemoclips are then applied to
prevent rebleeding
(c and d)
.

dilatation with a 30- to 40-mm balloon. Endoscopic dissection techniques (see Therapeutic colonoscopy ) are now being employed to treat achalasia by natural orifice myotomy (pero ral endoscopic myotomy; POEM) with good follow-up results. An alternative in unfit patients is injection of  botulinum toxin into the lower oesophageal sphincter, although this has a lim ited (3–6 /uni00A0 months) duration of  benefit. There are a limited n umber of  endoscopic techniques available to reduce gastro-oesophageal reflux, which rely on tightening the loose gastro-oesophageal junction by plication, by the applica tion of  radiofrequency ablation or by mucosal resection techniques. These may have a role in some patients but are yet to demonstrate benefit over surgical fundoplication. Endoscopic bariatric therapies, such as intragastric bal loons, sleeve gastroplasty and duodenal resurfacing, may all provide alternatives to more established surgical options. In contrast, there is clear evidence that the insertion of  a percu taneous endoscopic gastr ostomy (PEG) tube enhances nutri - tional and functional outcome in patients unable to maintain oral nutritional intake ( Figure 9.8 ). PEG insertion is often a - prelude to treatment of complex orofacial malignancy and y be used to support nutrition in patients with alternative ma malignant, degenerative or inflammatory diseases. - The deployment of  self-expanding metal stents with or without a co vering sheath inserted over a sti ff guidewire leads to a significant improvement in symptomatic dysphagia and quality of life in patients with malignant oesophageal and gastric outlet obstruction ( Figure 9.9 ) . Covered stents are the mainstay of  treatment for benign or malignant tracheo - oesophageal fistulae. It is now possible to endoscopically manage early oesoph - - ageal and gastric neoplasia with endoscopic m ucosal resec - tion (EMR) or endoscopic submucosal dissection (ESD). These techniques require specialist training but have allowed - 

Figure 9.7
A pyloric stricture
(a)
can be dilated using a
through-the-scope balloon
under direct vision to minimise
complications
(b)
.
(a)
Figure 9.8
A schematic
diagram of percutaneous
endoscopic gastrostomy
insertion. A standard endos
-
copy is performed to
ensure
that there are no contra
-
indications to
gastr
ostomy
insertion. The stomach is
insuf
/f_l
ated with air and a
direct percutaneous needle
puncture made at a point
where the stomach abuts the
abdominal wall. Lignocaine
(c)
is infused on withdrawal
(a)
.
A trocar is inserted and a
wire passed into the stom
-
ach, which can be caught
with a snare
(b)
. The scope
is withdrawn, pulling the
wir
e out through the mouth,
at which point it is attached
to the gastrostomy tube
(c)
.
The gastrostomy is pulled
through into the stomach
and out through the track
created by the trocar inser
-
tion
(d)
.
(b)
(d)

endoscopic management of  mucosal lesions that were previ ously subject to surgical intervention ( Figure 9.10 ). A prime example has been improved endoscopic treatment of  Barrett’s high-grade dysplasia and early oesophageal adenocarcinoma. Destruction of residual Barrett’s epithelium in cases of or high-grade dysplasia is possible with endoscopic ablation, and has been shown to reduce risk of  progression to cancer. The most commonly used technique for this purpose is radio- frequency ablation, where 360° ablation can be achieved with a balloon catheter, or more focused ablation with smaller probes. Cryotherapy and APC can also be used for ablation, but photodynamic therapy is now used much less often. 

Figure 9.10
Novel upper gastrointestinal therapeutic uses of oesoph
agogastroduodenoscopy include the use of endoscopic mucosal
resection to remove early gastric cancer leaving a clean base.

Therapeutic oesophagogastroduodenoscopy

Appropriate patient selection and monitoring are essential to minimise complications. The most common therapeutic endo scopic procedure performed as an emergency is the control of  upper gastrointestinal haemorrhage of  any aetiology . Band ligation has replaced sclerotherap y in the management of oesophageal varices ( Figure 9.4 ), whereas sclerotherapy using thrombin-based glues can be used to control blood loss from gastric and duodenal varices. Injection therapy with adrenaline (epinephrine) coupled with a second haemostatic technique such as thermal coagula tion or endoclip application is the technique of  choice for a peptic ulcer with active bleed ing or high-risk stigmata of haemorrhage ( Figure 9.5 ). Such high-risk bleeds should be followed by 72 /uni00A0 hours of  intravenous proton pump inhibition. Chronic blood loss from angioectasia is most safely treated with APC because of  the controlled depth of  burn compared with alternative thermal tec hniques ( Figure 9.6 ) . Haemostatic powders provide a further way to arrest bleeding; these work best for di ff use bleeding or as salvage therapy . Norman Rupert Barrett , 1903–1979, sur geon, St Thomas’s Hospital, London, UK. - - Benign oesophageal and pyloric strictures may be dilated under direct vision with through-the-scope (TTS) balloon dila - tors or the more traditional guidewire-based systems such as Savary–Gilliard bougie dilators ( Figure 9.7 ) . On occasion, more di ffi cult benign strictures can be treated by the insertion of a fully covered removable stent, or with a biodegradable stent. Likewise, the non-relaxing lower oesophageal sphincter associated with achalasia can be treated by pneumatic balloon 

(a)
(b)
(c)
(d)
Figure 9.6
The classic appearance of gastric antral vascular ectasia,
which is often treated with argon plasma coagulation.
Figure 9.5
A gastric ulcer with
active bleeding
(a)
is initially
treated with adrenaline injection
to achieve haemostasis
(b)
. Two
haemoclips are then applied to
prevent rebleeding
(c and d)
.

dilatation with a 30- to 40-mm balloon. Endoscopic dissection techniques (see Therapeutic colonoscopy ) are now being employed to treat achalasia by natural orifice myotomy (pero ral endoscopic myotomy; POEM) with good follow-up results. An alternative in unfit patients is injection of  botulinum toxin into the lower oesophageal sphincter, although this has a lim ited (3–6 /uni00A0 months) duration of  benefit. There are a limited n umber of  endoscopic techniques available to reduce gastro-oesophageal reflux, which rely on tightening the loose gastro-oesophageal junction by plication, by the applica tion of  radiofrequency ablation or by mucosal resection techniques. These may have a role in some patients but are yet to demonstrate benefit over surgical fundoplication. Endoscopic bariatric therapies, such as intragastric bal loons, sleeve gastroplasty and duodenal resurfacing, may all provide alternatives to more established surgical options. In contrast, there is clear evidence that the insertion of  a percu taneous endoscopic gastr ostomy (PEG) tube enhances nutri - tional and functional outcome in patients unable to maintain oral nutritional intake ( Figure 9.8 ). PEG insertion is often a - prelude to treatment of complex orofacial malignancy and y be used to support nutrition in patients with alternative ma malignant, degenerative or inflammatory diseases. - The deployment of  self-expanding metal stents with or without a co vering sheath inserted over a sti ff guidewire leads to a significant improvement in symptomatic dysphagia and quality of life in patients with malignant oesophageal and gastric outlet obstruction ( Figure 9.9 ) . Covered stents are the mainstay of  treatment for benign or malignant tracheo - oesophageal fistulae. It is now possible to endoscopically manage early oesoph - - ageal and gastric neoplasia with endoscopic m ucosal resec - tion (EMR) or endoscopic submucosal dissection (ESD). These techniques require specialist training but have allowed - 

Figure 9.7
A pyloric stricture
(a)
can be dilated using a
through-the-scope balloon
under direct vision to minimise
complications
(b)
.
(a)
Figure 9.8
A schematic
diagram of percutaneous
endoscopic gastrostomy
insertion. A standard endos
-
copy is performed to
ensure
that there are no contra
-
indications to
gastr
ostomy
insertion. The stomach is
insuf
/f_l
ated with air and a
direct percutaneous needle
puncture made at a point
where the stomach abuts the
abdominal wall. Lignocaine
(c)
is infused on withdrawal
(a)
.
A trocar is inserted and a
wire passed into the stom
-
ach, which can be caught
with a snare
(b)
. The scope
is withdrawn, pulling the
wir
e out through the mouth,
at which point it is attached
to the gastrostomy tube
(c)
.
The gastrostomy is pulled
through into the stomach
and out through the track
created by the trocar inser
-
tion
(d)
.
(b)
(d)

endoscopic management of  mucosal lesions that were previ ously subject to surgical intervention ( Figure 9.10 ). A prime example has been improved endoscopic treatment of  Barrett’s high-grade dysplasia and early oesophageal adenocarcinoma. Destruction of residual Barrett’s epithelium in cases of or high-grade dysplasia is possible with endoscopic ablation, and has been shown to reduce risk of  progression to cancer. The most commonly used technique for this purpose is radio- frequency ablation, where 360° ablation can be achieved with a balloon catheter, or more focused ablation with smaller probes. Cryotherapy and APC can also be used for ablation, but photodynamic therapy is now used much less often. 

Figure 9.10
Novel upper gastrointestinal therapeutic uses of oesoph
agogastroduodenoscopy include the use of endoscopic mucosal
resection to remove early gastric cancer leaving a clean base.

Therapeutic oesophagogastroduodenoscopy

Appropriate patient selection and monitoring are essential to minimise complications. The most common therapeutic endo scopic procedure performed as an emergency is the control of  upper gastrointestinal haemorrhage of  any aetiology . Band ligation has replaced sclerotherap y in the management of oesophageal varices ( Figure 9.4 ), whereas sclerotherapy using thrombin-based glues can be used to control blood loss from gastric and duodenal varices. Injection therapy with adrenaline (epinephrine) coupled with a second haemostatic technique such as thermal coagula tion or endoclip application is the technique of  choice for a peptic ulcer with active bleed ing or high-risk stigmata of haemorrhage ( Figure 9.5 ). Such high-risk bleeds should be followed by 72 /uni00A0 hours of  intravenous proton pump inhibition. Chronic blood loss from angioectasia is most safely treated with APC because of  the controlled depth of  burn compared with alternative thermal tec hniques ( Figure 9.6 ) . Haemostatic powders provide a further way to arrest bleeding; these work best for di ff use bleeding or as salvage therapy . Norman Rupert Barrett , 1903–1979, sur geon, St Thomas’s Hospital, London, UK. - - Benign oesophageal and pyloric strictures may be dilated under direct vision with through-the-scope (TTS) balloon dila - tors or the more traditional guidewire-based systems such as Savary–Gilliard bougie dilators ( Figure 9.7 ) . On occasion, more di ffi cult benign strictures can be treated by the insertion of a fully covered removable stent, or with a biodegradable stent. Likewise, the non-relaxing lower oesophageal sphincter associated with achalasia can be treated by pneumatic balloon 

(a)
(b)
(c)
(d)
Figure 9.6
The classic appearance of gastric antral vascular ectasia,
which is often treated with argon plasma coagulation.
Figure 9.5
A gastric ulcer with
active bleeding
(a)
is initially
treated with adrenaline injection
to achieve haemostasis
(b)
. Two
haemoclips are then applied to
prevent rebleeding
(c and d)
.

dilatation with a 30- to 40-mm balloon. Endoscopic dissection techniques (see Therapeutic colonoscopy ) are now being employed to treat achalasia by natural orifice myotomy (pero ral endoscopic myotomy; POEM) with good follow-up results. An alternative in unfit patients is injection of  botulinum toxin into the lower oesophageal sphincter, although this has a lim ited (3–6 /uni00A0 months) duration of  benefit. There are a limited n umber of  endoscopic techniques available to reduce gastro-oesophageal reflux, which rely on tightening the loose gastro-oesophageal junction by plication, by the applica tion of  radiofrequency ablation or by mucosal resection techniques. These may have a role in some patients but are yet to demonstrate benefit over surgical fundoplication. Endoscopic bariatric therapies, such as intragastric bal loons, sleeve gastroplasty and duodenal resurfacing, may all provide alternatives to more established surgical options. In contrast, there is clear evidence that the insertion of  a percu taneous endoscopic gastr ostomy (PEG) tube enhances nutri - tional and functional outcome in patients unable to maintain oral nutritional intake ( Figure 9.8 ). PEG insertion is often a - prelude to treatment of complex orofacial malignancy and y be used to support nutrition in patients with alternative ma malignant, degenerative or inflammatory diseases. - The deployment of  self-expanding metal stents with or without a co vering sheath inserted over a sti ff guidewire leads to a significant improvement in symptomatic dysphagia and quality of life in patients with malignant oesophageal and gastric outlet obstruction ( Figure 9.9 ) . Covered stents are the mainstay of  treatment for benign or malignant tracheo - oesophageal fistulae. It is now possible to endoscopically manage early oesoph - - ageal and gastric neoplasia with endoscopic m ucosal resec - tion (EMR) or endoscopic submucosal dissection (ESD). These techniques require specialist training but have allowed - 

Figure 9.7
A pyloric stricture
(a)
can be dilated using a
through-the-scope balloon
under direct vision to minimise
complications
(b)
.
(a)
Figure 9.8
A schematic
diagram of percutaneous
endoscopic gastrostomy
insertion. A standard endos
-
copy is performed to
ensure
that there are no contra
-
indications to
gastr
ostomy
insertion. The stomach is
insuf
/f_l
ated with air and a
direct percutaneous needle
puncture made at a point
where the stomach abuts the
abdominal wall. Lignocaine
(c)
is infused on withdrawal
(a)
.
A trocar is inserted and a
wire passed into the stom
-
ach, which can be caught
with a snare
(b)
. The scope
is withdrawn, pulling the
wir
e out through the mouth,
at which point it is attached
to the gastrostomy tube
(c)
.
The gastrostomy is pulled
through into the stomach
and out through the track
created by the trocar inser
-
tion
(d)
.
(b)
(d)

endoscopic management of  mucosal lesions that were previ ously subject to surgical intervention ( Figure 9.10 ). A prime example has been improved endoscopic treatment of  Barrett’s high-grade dysplasia and early oesophageal adenocarcinoma. Destruction of residual Barrett’s epithelium in cases of or high-grade dysplasia is possible with endoscopic ablation, and has been shown to reduce risk of  progression to cancer. The most commonly used technique for this purpose is radio- frequency ablation, where 360° ablation can be achieved with a balloon catheter, or more focused ablation with smaller probes. Cryotherapy and APC can also be used for ablation, but photodynamic therapy is now used much less often. 

Figure 9.10
Novel upper gastrointestinal therapeutic uses of oesoph
agogastroduodenoscopy include the use of endoscopic mucosal
resection to remove early gastric cancer leaving a clean base.

# UNDERGOING ENDOSCOPY

UNDERGOING ENDOSCOPY

Many patients undergoing endoscopy may be taking a medica tion that interferes with normal haemostasis, such as warfarin, heparin, direct oral anticoagulants, clopidogrel or aspirin. The key points to remember when managing anticoagulants in patients undergoing endoscopy are given in Summary box /uni00A0 9.4 . Summary box 9.4 Managing anticoagulants in patients undergoing endoscopy /uni25CF /uni25CF /uni25CF 

It is important to recognise and understand:
The risk of complications related to the underlying
gastrointestinal disease from anticoagulant therapy
The risk of haemorrhage related to an endoscopic procedure in
the setting of anticoagulant therapy
The risk of a thromboembolic/ischaemic event related to
interruption of anticoagulant therapy

UNDERGOING ENDOSCOPY

Many patients undergoing endoscopy may be taking a medica tion that interferes with normal haemostasis, such as warfarin, heparin, direct oral anticoagulants, clopidogrel or aspirin. The key points to remember when managing anticoagulants in patients undergoing endoscopy are given in Summary box /uni00A0 9.4 . Summary box 9.4 Managing anticoagulants in patients undergoing endoscopy /uni25CF /uni25CF /uni25CF 

It is important to recognise and understand:
The risk of complications related to the underlying
gastrointestinal disease from anticoagulant therapy
The risk of haemorrhage related to an endoscopic procedure in
the setting of anticoagulant therapy
The risk of a thromboembolic/ischaemic event related to
interruption of anticoagulant therapy

UNDERGOING ENDOSCOPY

Many patients undergoing endoscopy may be taking a medica tion that interferes with normal haemostasis, such as warfarin, heparin, direct oral anticoagulants, clopidogrel or aspirin. The key points to remember when managing anticoagulants in patients undergoing endoscopy are given in Summary box /uni00A0 9.4 . Summary box 9.4 Managing anticoagulants in patients undergoing endoscopy /uni25CF /uni25CF /uni25CF 

It is important to recognise and understand:
The risk of complications related to the underlying
gastrointestinal disease from anticoagulant therapy
The risk of haemorrhage related to an endoscopic procedure in
the setting of anticoagulant therapy
The risk of a thromboembolic/ischaemic event related to
interruption of anticoagulant therapy

# UPPER GASTROINTESTINAL ENDOSCOPY

UPPER GASTROINTESTINAL ENDOSCOPY

OGD is the most commonly performed endoscopic procedure. Excellent visualisation of  the oesophagus, gastro-oesophageal junction, stomach, duodenal bulb and second part of  the duodenum can be obtained. Retroversion of  the gastroscope in the stomach is essential to obtain complete views of  the gastric cardia and fundus ( Figure 9.3 ). Traditional forward-viewing endoscopes do not adequately visualise the ampulla, and a side-viewing scope should be used if  this is essential. Likewise, - although it is possible to reach the third part of  the duodenum with a standard 120-cm instrument, a longer enteroscope is required if  views beyond the ligament of  Treitz are r equired. In addition to clear mucosal views, diagnostic endoscopy allows mucosal biopsies to be taken, which may either undergo processing for histological examination or be used for near-patient detection of Helicobacter pylori infection using a commercial urease-based kit. In addition, brushings may be taken for cytology and aspirates for microbiological culture. - UPPER GASTROINTESTINAL ENDOSCOPY

OGD is the most commonly performed endoscopic procedure. Excellent visualisation of  the oesophagus, gastro-oesophageal junction, stomach, duodenal bulb and second part of  the duodenum can be obtained. Retroversion of  the gastroscope in the stomach is essential to obtain complete views of  the gastric cardia and fundus ( Figure 9.3 ). Traditional forward-viewing endoscopes do not adequately visualise the ampulla, and a side-viewing scope should be used if  this is essential. Likewise, - although it is possible to reach the third part of  the duodenum with a standard 120-cm instrument, a longer enteroscope is required if  views beyond the ligament of  Treitz are r equired. In addition to clear mucosal views, diagnostic endoscopy allows mucosal biopsies to be taken, which may either undergo processing for histological examination or be used for near-patient detection of Helicobacter pylori infection using a commercial urease-based kit. In addition, brushings may be taken for cytology and aspirates for microbiological culture. - UPPER GASTROINTESTINAL ENDOSCOPY

OGD is the most commonly performed endoscopic procedure. Excellent visualisation of  the oesophagus, gastro-oesophageal junction, stomach, duodenal bulb and second part of  the duodenum can be obtained. Retroversion of  the gastroscope in the stomach is essential to obtain complete views of  the gastric cardia and fundus ( Figure 9.3 ). Traditional forward-viewing endoscopes do not adequately visualise the ampulla, and a side-viewing scope should be used if  this is essential. Likewise, - although it is possible to reach the third part of  the duodenum with a standard 120-cm instrument, a longer enteroscope is required if  views beyond the ligament of  Treitz are r equired. In addition to clear mucosal views, diagnostic endoscopy allows mucosal biopsies to be taken, which may either undergo processing for histological examination or be used for near-patient detection of Helicobacter pylori infection using a commercial urease-based kit. In addition, brushings may be taken for cytology and aspirates for microbiological culture. -

# Urgent endoscopy for gastrointestinal bleeding in

Urgent endoscopy for gastrointestinal bleeding in the anticoagulated patient

The risk of  clinically significant gastrointestinal bleeding in patients on warfarin is increased, particularly in patients with a past history of  similar events, if  the international normalised ratio (INR) is above the therapeutic range or if  the patient is taking concomitant aspirin/non-steroidal anti-inflammatory drugs (NSAIDs). In these situations, the risk of  reversing the anticoagulation must be weighed against the risk of  ongoing haemorrhage. If  complete reversal is not appropriate, correc tion of  the INR to approximately 1.5 is usually su ffi cient to allow endoscopic diagnosis and therapy . Anticoagulation can often be resumed 24 hours after successful endoscopic therapy ( Figure 9.2 ).

# Urgent endoscopy for gastrointestinal bleeding in the anticoagulated patient

Urgent endoscopy for gastrointestinal bleeding in the anticoagulated patient

The risk of  clinically significant gastrointestinal bleeding in patients on warfarin is increased, particularly in patients with a past history of  similar events, if  the international normalised ratio (INR) is above the therapeutic range or if  the patient is taking concomitant aspirin/non-steroidal anti-inflammatory drugs (NSAIDs). In these situations, the risk of  reversing the anticoagulation must be weighed against the risk of  ongoing haemorrhage. If  complete reversal is not appropriate, correc tion of  the INR to approximately 1.5 is usually su ffi cient to allow endoscopic diagnosis and therapy . Anticoagulation can often be resumed 24 hours after successful endoscopic therapy ( Figure 9.2 ).

# Urgent endoscopy for gastrointestinal bleeding in

Urgent endoscopy for gastrointestinal bleeding in the anticoagulated patient

The risk of  clinically significant gastrointestinal bleeding in patients on warfarin is increased, particularly in patients with a past history of  similar events, if  the international normalised ratio (INR) is above the therapeutic range or if  the patient is taking concomitant aspirin/non-steroidal anti-inflammatory drugs (NSAIDs). In these situations, the risk of  reversing the anticoagulation must be weighed against the risk of  ongoing haemorrhage. If  complete reversal is not appropriate, correc tion of  the INR to approximately 1.5 is usually su ffi cient to allow endoscopic diagnosis and therapy . Anticoagulation can often be resumed 24 hours after successful endoscopic therapy ( Figure 9.2 ).