Ketamine for analgosedative therapy in intensive care treatment of head-injured patients

Ketamine was supposed to be contra-indicated in head injured patients although it possesses numerous advantages over other commonly used analgosedative drugs. Referring to these potential advantages and the lack of definitive data about its effect upon ICP, CPP or neurological development, we conducted a prospective study in which moderate or severely head injured patients (n = 35) were prospectively allocated to receive treatment either with a combination of ketamine and midazolam or fentanyl and midazolam. The initial dose was 6.5 mg/kg/day midazolam, 65 mg/kg/day ketamine or 65 mu g/kg/day fentanyl and was later adjusted due to clinical requirements for a period of 3 to 14 days. Comparably high dosages of detamine have been found necessary (104 mg/kg/day). Four patients from the ketamine group (n = 17) and 5 from the control group (n = 18) were withdrawn during treatment due to persistent ICP above 25 mm Hg, countermeasured by barbiturate coma. Two more patients were withdrawn due to development of cardiovascular arrest (ketamine group) and multi organ failure. A comparison of the remaining patients revealed a lower requirement of catecholamines (significant on first day, p<0.05), an on average 8 mm Hg higher cerebral perfusion pressure and a 2 mm Hg higher intracranial pressure in the fentanyl group. Enteral food intake was better in the study group. The outcome was comparable in both groups with or without inclusion of withdrawn patients.