Air Embolism — Emergency

Air embolism is the sudden entry of air or other gas into the venous or arterial circulation, leading to mechanical obstruction of pulmonary or systemic vessels and acute cardiopulmonary or neurological compromise.

Causes include central venous catheter insertion or removal, trauma, neurosurgery in sitting position, decompression sickness in divers, mechanical ventilation with high pressures, hemodialysis circuits and laparoscopic insufflation.

Venous air embolism typically presents with sudden dyspnea, hypoxia, hypotension and a churning mill-wheel murmur; massive emboli cause obstructive shock and right ventricular failure.

Arterial or paradoxical air embolism (through patent foramen ovale or pulmonary arteriovenous shunt) may produce stroke-like neurological deficits, seizures, myocardial ischemia and skin marbling.

Diagnosis relies on clinical suspicion in the appropriate setting; transesophageal echocardiography is the most sensitive bedside tool. Treatment includes immediate left lateral Trendelenburg position (Durant maneuver), 100% oxygen, hemodynamic support and hyperbaric oxygen for severe arterial embolism.