Highlights • None of recent studies on accident rates HEMS missions have investigated the influence of the seating position. • A total of n =99 accidents were investigated. • The person in the “patient” position was most likely to suffer from deadly injuries (44.9%). • The patients’ position and the HEMS crew member rear seat were found to be at the highest risk for fatal or severe injuries. • These results support the urgent requirement of an international data base to improve the outcome after HEMS accidents.

Abstract Introduction Accident rates and fatality rates for Helicopter Emergency Medical Service (HEMS) missions have been investigated recently, but none of these studies considered the influence of the seating position in the helicopter. The aim of the present descriptive and observational study was to analyze injury severity depending on the seating position during HEMS accidents in Germany. Material and methods Data from the German Federal Agency for Flight Accident Investigation was gathered for a period of 40 years (from 1970 to 2009). The seating position in the aircraft during the accident and the resulting injury severity (i.e., 1=no; 2=slight; 3=severe; and 4=fatal) were recorded. Injury severity was compared using the Fisher's exact test. P values <0.05 were considered statistically significant. Results A total of n =99 accidents were investigated (n =61 accidents did not lead to any injuries in the occupants, n =7 accidents resulted in minor, and n =6 in severe injuries, and lethal injuries resulted from n =15 accidents). The occupant in the “patient” position was most likely to suffer from deadly injuries (44.9%), followed by the HEMS crew member rear seat (25.0%), compared to lower lethality rates in the other seating positions (9.4–11.2%). Sitting on the HEMS crew member rear seat also was associated with the highest percentage of severe and minor injuries (12.5% each). Conclusions In HEMS accidents, the patients’ position and the HEMS crew member rear seat were found to be at the highest risk for fatal or severe injuries. These results support the urgent requirement of a large international data base for HEMS accidents as a basis for further studies to improve the safety in HEMS missions.