PROPOFOL SEDATION IN SEVERE HEAD-INJURY FAILS TO CONTROL HIGH ICP, BUT REDUCES BRAIN METABOLISM

We have compared the effects of an intravenous infusion of propofol wi th those of morphine and midazolam on global brain metabolism (AVDO2) and brain perfusion following severe head injury. Fifteen patients wer e sedated with either a continuous infusion of propofol (mean rate 232 mg/h, range 150-400 mg/h) or infusions of morphine (mean rate 2.3 mg/ h, range 0-4 mg/h) and midazolam (mean rate 2.8 mg/h, range 0-5 mg/h). Both groups were well matched for sex, age and level of coma (Glasgow coma scale) prior to sedation. Continuous data collection of AVDO2, m ean arterial blood pressure (MABP), intracranial pressure (ICP), and c erebral perfusion pressure (CPP) began at 12 hours post injury and con tinued for a mean period of 40 hours. Morphine and midazolam did not h ave a significant effect on any of the measured parameters. Propofol l ed to a fall in AVDO2 from 6.0 +/- 2.6ml/dl to 3.0 +/- 0.6 ml/dl at 4 hours. However, there was no effect on MABP, ICP or CPP. Outcome was s imilar in the 2 groups.