Sir,We report a case of venous air embolism (VAE) in a 48-year-old female, suffering from locally advanced carcinoma gall bladder with obstructive jaundice, posted for endoscopic retrograde cholangiopancreatography (ERCP) in prone position under general anaesthesia (GA). The patient had a history of yellowish discolouration of the skin associated with itching for 2–3 months and clay-coloured stools for 2 months. Pre-procedure bilirubin levels were 23.7 mg/dL. Anaesthesia was induced with intravenous (IV) fentanyl, propofol and atracurium, and prone position was given after endotracheal intubation. An endoscopic sphincterotomy was performed, and contrast was injected followed by an air cholangiogram. A sudden drop in end-tidal CO2 (EtCO2) from 60 to 8, hypotension and bradycardia were noted, followed by cardiac arrest [Figure 1]. VAE was suspected. The procedure was abandoned, the patient was made supine, nitrous oxide was stopped and the lungs were ventilated with 100% O2. The patient was resuscitated with Ringer's lactate, and cardiopulmonary resuscitation (CPR) was started. Adrenaline 1 mg IV bolus was given. Return of spontaneous circulation was achieved after four cycles of CPR. A central venous line was secured, but no air could be aspirated through it. The patient was shifted to the Intensive Care Unit, was haemodynamically stable and was extubated 5 h after this episode. Two days later, she underwent an uneventful percutaneous transhepatic biliary drainage and was discharged home on the 14th day.
Figure 1
Monitor picture showing a fall in the end-tidal CO2 and haemodynamic parameters
Monitor picture showing a fall in the end-tidal CO2 and haemodynamic parametersERCP is a common procedure for the diagnosis and treatment of various pancreatic and biliary diseases. The complications following ERCP include post-ERCP pancreatitis, cholangitis, bleeding or perforation after sphincterotomy. Air embolism is a very rare endoscopic complication but possesses the potential to be severe and fatal.[12345] The risk factors for an air embolism following an ERCP are previous interventions or surgeries of the bile duct system, transhepatic portosystemic shunts, percutaneous transhepatic biliary drains, blunt or penetrating trauma to the liver, sphincterotomy, metal stent placement, the inflammation of the bile duct or surrounding veins, hepatic abscesses or tumours, liver biopsy and insufflation of air with high pressure. Cholangioscopy with air insufflation directly into the bile duct appears to be a particularly strong risk factor for an air embolism.[1] Symptoms may be non-specific, and therefore, a high index of clinical suspicion for a possible air embolism is required.[1] VAE is a diagnosis of exclusion because air may be rapidly absorbed from the circulation as in our case while diagnostic tests are being arranged. EtCO2 monitoring, echocardiography, pulmonary artery catheterization and computed tomography scan are some of the aids in establishing the diagnosis of VAE.Management includes (1) immediate cessation of the procedure, (2) administration of high flow 100 % oxygen, discontinuation of N2O, (3) high volume normal saline infusion and (4) Trendelenburg and left lateral decubitus position. Other manoeuvres include air aspiration through a central venous catheter, hyperbaric oxygen therapy, cardiopulmonary resuscitation (CPR) if haemodynamic collapse.[1] In the event of circulatory collapse, CPR should be initiated to maintain the cardiac output and to break large air bubbles into smaller ones and force air out of the right ventricle into the pulmonary vessels.[1]We stress the importance of capnography here, for successful diagnosis of VAE which is an uncommon complication following ERCP in the endoscopy suite.
Figure 1