CAUSTIC INJURY

CAUSTIC INJURY

Caustic injury to the oesophagus can be mild, but also is - potentially lethal. Most caustic ingestions occur in children, in whom it is usually accidental, or in adults with suicidal intent. The severity of the injury depends on the type, pH, quantity strong acid, causing coagulative necrosis with eschar forma tion, which may limit penetration to deeper layers, or strong alkali, leading to liquefactive necrosis. The latter potentially penetrates deeper into the oesophageal wall, producing a more se vere injury pattern. Diagnosis is usually not di ffi cult. When the injurious agent is identified, it should be tested for its pH, and suicidal attempt considered. Patients ma y have pain in the neck, throat, chest or even the abdomen. Drooling of saliva, dysphagia and ody nophagia can be present. Hoarseness of voice is an important sign to look for as it may signify laryngeal injury and potential airway obstruction. If the airway is judged to be compromised, careful assessment and emergency intubation using fibreoptic guidance, or even a surgical airway , are indicated. There is no role for gastric lavage or attempts to neutralise the acid or alkali. Initial treatment after securing an adequate airway is supportive, with intravenous fluid, oxygen supplementation and cardiorespiratory monitoring. Once the patient is stabilised, an endoscopy and CT scan with intravenous contrast should be considered. Care ful endoscopy allows assessment of the extent of the injury ( Figure 66.34 ). The Zargar g rading can be used ( Table 66.2 In general, the longer and more circumferential the injury , the more likely that strictur e will form. The stomach is assessed as well for injury , and a nasogastric/duodenal tube can be placed with endoscopic guidance. This can be used for ali mentary nutritional support; if a stricture forms, there is still a potential route of access through to the stomach. A CT scan can assess oesophageal oedema and also surrounding soft- tissue infiltration. Most caustic injuries can be managed conservatively with supportiv e measures. Deterioration requires surgical treat ment, with emergency oesophagectomy . T he oesophagus can be mobilised transhiatally or via a thoracoscopic approach. Immediate reconstruction is not recommended. A cervical oesophagostomy and a gastrostomy can be done and future reconstruction planned. A feeding jejunostomy is an alterna tiv e for nutritional support if the stomach also requires resec tion. Delayed complications include stricture and malignancy . A stricture can form early and may be resistant to dilatation ( Figure 66.35 ). There is not enough evidence to support rou tine use of systemic steroids, intralesional injection of steroid or topical mitomycin C to reduce stricture formation. Endoscopic dilatation should be gradual, as the perforation rate is higher than in other forms of strictures . Long strictures are often resis tant to dilatation. Oesophagectomy or bypass surgery may be required. Oesophagectomy has the advantage of removing the oesophagus with its long-term risk of malignancy . However, surgery is di ffi cult because of scarring and adhesions to the mediastinum, thus a bypass operation may be preferable. The gastric conduit is placed in the retrosternal route to reach the neck. When it is also damaged and cannot be used, a colonic interposition is the alternative. The native oesophagus can be left in situ as the risk of dilatation and resultant mucocele is low . Showkat Ali Zargar , contemporary , gastroenterologist, Sher-i-Kashmir Institute of Medical Sciences, Srinagar, India. Burrill Bernard Crohn , 1884–1983, gastroenterologist, Mount Sinai Hospital, New Y ork, NY , USA, described regional ileitis in 1932. - - - ). - - - -

injury to the oesophagus. Zargar classi /f_i cation Description grade 0 Normal appearance 1 Oedema and hyperaemia 2a Super /f_i cial ulceration and friability 2b Deep ulceration or circumferential ulceration 3a Multiple deep ulceration ad scattered necrosis 3b Extensive necrosis 4 Perforation Figure 66.34 Endoscopy picture showing caustic burn to the oesophagus.