Bradycardia due to hydrogen peroxide irrigation during craniotomy for craniopharyngioma.

Complications of hydrogen peroxide have been described in the literature and typically involve the effects of O(2) emboli. We report a 15-year-old male patient undergoing right frontal craniotomy and excision of craniopharyngioma. A sudden bradycardia occurred after instillation of hydrogen peroxide solution at the surgical site. Stimulation of the anterior hypothalamus after removal of the tumor and hydrogen peroxide irrigation may have triggered intense parasympathetic activity leading to bradycardia. The other possible causes for the complication are discussed.