54-year-old woman with brain gas emboli after an accidental ingestion of concentrated hydrogen peroxide was described. Hydrogen peroxide (H2O2) is a water-soluble, caustic liquid. Exposure to concentrated (> 30-35%) hydrogen peroxide may cause cardiorespiratory insufficiency, shock, convulsions, coma, and chemical burns of skin and mucous membranes. Arterial gas embolization in central nervous system is a relatively rare complication. There are three possible mechanisms of gas embolization: persisting patent foramen ovale, pulmonary gas emboli caused by aspiration of hydrogen peroxide to the lower respiratory tract, formation of gas emboli after reaching the brain. Absence of gas emboli and cerebral infarction in CT does not exclude intoxication. Hyperbaric therapy is most effective for brain air embolism complicating hydrogen peroxide poisoning in acute phase. Some authors suggested that this therapy is also effective if administered during the subacute phase. Neurologic symptoms after ingestion of hydrogen peroxide may suggest gas embolism of the cerebral vasculature. The absence of atrial septal defect does not exclude the possibility of cerebral air embolism. The absence of gas and cerebral infarction in CT scans does not exclude brain gas embolism. The use of hyperbaric therapy should be considered in treating severe cases of hydrogen peroxide poisoning.

Ciechanowicz, Sein Anand, Chodorowski, Kujawska-Danecka, , , , , (2007). [Acute intoxication with hydrogen peroxide with air emboli in central nervous system–a case report].¬†Przeglad lekarski, 2007 ;64(4-5):339-40.¬†https://www.ncbi.nlm.nih.gov/pubmed/17724906