Cerebral Air Embolism as Possible Cause of Stroke During Therapeutic Endobronchial Application of Argon Plasma Coagulation

A 68-year-old male was admitted for evaluation of an endobronchial mass obstructing the right middle lobe (RML) and right lower lobe (RLL) of the lung. Flexible bronchoscopy revealed a notable endobronchial lesion in the bronchus intermedius that completely obstructed the RML and the RLL. Argon plasma coagulation (APC) at 30 watts and gas flow at 0.8 liters/minute to 1 liter/minute were applied to the tumor. In the recovery room, the patient was discovered to have a left-sided facial droop and left-sided weakness. The initial computed tomography (CT) scan of the brain and an angiogram of the head and neck were normal, but a repeat CT scan of the head several hours later was remarkable for an area of hypoattenuation in the right frontoparietal lobe concerning for infarct. A magnetic resonance imaging (MRI) brain scan confirmed acute to sub-acute cortical infarcts. Given the direct temporal relation between the onset of neurologic symptoms and the usage of APC with bronchoscopy, a cerebral air embolism (CAE) was thought to be the cause of the patient’s acute stroke.