Anti-seizure prophylaxis in critically ill patients with traumatic brain injury in an intensive care unit

The objectives of this prospective observational study were to determine the proportion of patients with traumatic brain injury who received effective anti-seizure prophylaxis. The study was conducted in a tertiary level ICU of a major trauma referral centre between February 2012 and August 2013. A total of 2361 patients were admitted to the ICU in this study period, of whom 125 patients (index) with traumatic head injury were included in this study. The patients had a mean age of 45 years (SD=19), a mean score on the Glasgow Coma Scale of 9 (SD=4), a mean injury severity score of 27 (SD=13) and a mean APACHE III score of 55 (SD=27). Only 13.6 % (17 of 125) of patients were given anti-seizure prophylaxis and phenytoin levels were measured in 9.6% (12 of 125). Although all 12 patients achieved an effective concentration for phenytoin therapy (>40 μmol/l) after the loading dose, no patient had their target concentration consistently maintained in the recommended therapeutic range (40 to 80 μmol/l) throughout the seven-day monitoring period. There was wide fluctuation in phenytoin levels in the patients in this study. Twenty-two (18%) of the index patients had post-traumatic seizures, indicating a high prevalence for this study. Poor compliance with guidelines could possibly explain this phenomenon. Future studies are needed to look at the dosing and monitoring of phenytoin and/or alternative anti-seizure prophylaxis in patients with traumatic brain injury.