Iatrogenic cerebral air embolism: importance of an early hyperbaric oxygenation

Objectives: To assess the relationship between the time period before hyperbaric oxygenation therapy (HBO) and clinical outcome in patients with iatrogenic cerebral air embolism. Design and setting: Retrospective study in a hyperbaric chamber and medical intensive care unit of a university hospital. Patients: All patients with air embolism from 1980 to 1999. Interventions: We retrieved the cases of 86 patients who benefited from an identical HBO and analyzed the relationship between the time period before HBO and clinical outcome. Results: Patients treated with HBO less than 6 h had a better outcome than those treated later. In patients treated within this delay the cause was venous air embolism in 84% and arterial air embolism in only 16% of cases. After this delay the cause was venous air embolism (53%) and arterial air embolism (47%). Patients with venous air embolism and recovery had a shorter delay than patients with sequelae or death (2 h 15 min vs. 4 h). Patients with venous air embolism treated less than 6 h had a better outcome than those treated later. In patients with arterial air embolism the time period before HBO was longer than in venous air embolism (8 h vs. 3 h) and the outcome worse (recovery in 35% vs. 67%). In patients with arterial air embolism no difference in the time period was found between patients with recovery and sequelae or death. Conclusions: We stress the beneficial effect of an early HBO in air embolism, the importance of an increased awareness of physicians concerned with this severe complication, and the need to develop techniques to detect air ernboli in the cerebral circulation.