Other forms of embolism

Other forms of embolism

Infective emboli of bacteria or an infected clot may cause mycotic aneurysms, septicaemia or infected infarcts. Parasitic emboli, caused by the ova of T aenia echinococcus and sanguinis hominis , may occur in some countries. Tumour cells (e.g. hypernephroma and cardiac myxoma) are rare causes of emboli. Fat embolism may follow major bony fractures. However, it usually causes venous emboli that trav el to the lungs and cause acute respiratory distress syndrome. Air embolism Air may be accidentally injected into the venous circulation or sucked into an open vein during head and neck surgery or a cut throat. It may also occur following Fallopian tube insu ffl ation or illegal abortion. If a large volume of air reaches the right side of the heart it may form an airlock within the pulmonary artery and cause acute right heart failure. The treatment of air embolism is to put the patient in a head-down (Trendelenburg) position to encourage the air to enter the veins in the lower part of the body . The patient should also be placed on the left side to help the air to float to the ventricular apex, away from the ostium of the pulmonary artery . In extreme cases air may be aspirated from the heart through a needle introduced below the left costal margin. Therapeutic embolisation This is used to arrest haemorrhage from the gastrointestinal, urinary , gynaecological and respiratory tracts, to treat arterio venous malformations by blocking their arterial supply and to control the growth of unresectable tumours. Arterial embolisation requires accurate selective catheterisation using the Seldinger technique . A variety of materials may be used, including Gelfoam sponge, plastic microspheres, balloons, ethyl alcohol, quick-setting plastics and metal coils.