Effect of ketamine on intracranial pressure in hydrocephalic children

Intracranial pressure changes were observed in 10 children with hydrocephalus after ketamine administration. Three patients showed an elevation of pressure and a fall was observed in 7 patients. Two more patients who were given ketamine while under general anaesthesia and IPPV also showed a fall in pressure. No explanation is forthcoming at present for such an unusual response, but an altered cerebral vascular response in the presence of promethazine and general anaesthesia has been postulated.