Alterations in intracranial pressure following ketamine anesthesia in hydrocephalic children.

Intracranial pressure was measured in 12 hydrocephalic children during ketamine anesthesia. Of the four who received no premedication, intracranial pressure increased in three and decreased in one patient. Seven out of eight children who received premedication with trimeperazine tartrate (3 mg/kg) orally showed a decrease in pressure. One patient who had a high initial pressure showed a steep rise necessitating termination of the study. Second dose of ketamine (1 mg/kg iv) produced a fall in all patients, being more prominent in those who had an elevation after the first dose. It is possible that the premedicants alter the response of cerebral vasculature to ketamine leading to a fall in intracranial pressure. Another possibility is that the standard intravenous dose of ketamine (2 mg/kg) is not uniformly effective in all patients of hydrocephalus. [ABSTRACT FROM AUTHOR]