The incidence and outcome of severe brain trauma - Design and first results of an epidemiological study in an urban area

Epidemiological data on the incidence, the prehospital and hospital care an d the outcome of traumatic brain injury in Germany are scarce. It is theref ore difficult to estimate the importance of this injury with respect to mag nitude as well as effectiveness and efficiency of therapeutic concepts. We therefore planned a study that was supposed to provide population based epi demiological data in the field of severe brain trauma from the site of the accident until discharge from hospital. All 90,000 prehospital emergencies that were cared for by emergency physici ans in Cologne from January 1990 until December 1996 were screened for iden tification of severe brain trauma. Their clinical course was reviewed using standard records and patients were included if they had their accident wit hin the city of Cologne and fullfilled the final inclusion criteria of GCS less than or equal to 8 or AIS(Head) greater than or equal to 3. 650 eligib le patients were identified of whom 530 had complete datasets (follow-up 80 %). Univariate statistical analysis was performed for all relevant variabl es. The main study endpoints were incidence and outcome of severe brain tra uma. The annual incidence of severe brain trauma in Cologne (1 mio. inhabitants) was 93. The average age was 39 years and 71 % of the patients were male. T he average prehospital GCS was 6.8, the average prehospital Trauma Score wa s 8.3 points. 49 % of the study population suffered from multiple injuries. The overall mortality rate was 46,6 %. 60 % of deaths occurred within the prehospital setting. The incidence of severe brain trauma in Cologne in this study was significa ntly lower compared to what could be expected from the literature. The over all mortality was high, especially the high prehospital death rate is strik ing.