[Massive cerebral air embolism following endoscopic retrograde cholangiopancreatography. A case report and review of the literature].

INTRODUCTION: Cerebral air embolism following endoscopic processes is an infrequent complication, but can have catastrophic consequences. CASE REPORT: An 85-year-old male diagnosed with distal cholangiocarcinoma with criteria for unresectability who was submitted to placement of a biliary drainage prosthesis. Endoscopic retrograde cholangiopancreatography was performed to change the prosthesis. After the procedure, the patient's vital signs and level of consciousness underwent a decline, and orotracheal intubation was required. A computerised axial tomography scan of the head showed evidence of a massive air embolism with focal points of hyperacute ischaemia in both hemispheres. The patient later died.
CONCLUSIONS: Cerebral air embolism following endoscopic retrograde cholangiopancreatography is infrequent, but potentially lethal. Manipulation of the bilio-intestinal wall in endoscopic examinations could give rise to communications between the lumen and the venous system. This, together with the high insufflation pressure used to conduct this test, would condition the passage of air to the portal venous system, and from there to the circulatory system. In the central nervous system, air bubbles would lead to a vascular obstruction, with the subsequent ischaemia and necrosis of tissues. An early diagnosis and life support therapy are essential. Its timely management can contribute to a better prognosis which, at least initially, is gloomy.