Delayed-onset cerebral arterial gas embolism in a commercial airline mechanic.

A commercial airline mechanic was evaluated for right-sided hemianesthesia. Thorough diagnostic testing failed to identify a definitive etiology, and the mechanic was assessed as having symptoms of a left internal capsule lesion, likely from an ischemic event. On day 12 after symptom onset, he consulted a diving medicine specialist for clearance to continue recreational scuba diving. A thorough history revealed that the patient worked regularly in a compressed air environment of commercial aircraft and had experienced a rapid decompression approximately 48 h prior to onset of the hemianesthesia. The specialist considered pulmonary barotrauma-induced cerebral arterial gas embolism as a possible diagnosis. On day 13 he was treated with hyperbaric oxygen using Treatment Table VI, which produced immediate relief. Following three additional hyperbaric oxygen treatments in the next 11 d, he reported nearly total resolution of his symptoms. This occurrence is believed to be the second report of a cerebral arterial gas embolism in an aircraft mechanic or maintenance crewman and suggests that the latency between time of depressurization and the development of symptoms from a pulmonary barotrauma-induced cerebral arterial gas embolism may extend longer than previously believed.