A review of the activation triggers and reasons for stand downs of a Helicopter Emergency Medical Service (HEMS)

Results Of the 561 jobs HEMS was deployed on in this time period, 226 (38%) were stand downs. All mechanisms of injury has a >25% stand down rate with assault jobs having the most (57%). 34% of stand downs were due to major injuries turning out to be minor although 20% of jobs did not have documented reasons. Interestingly, only 10% of stand downs were due to technical issues such as weather, re-tasking (sent to another job) or delays en route. In total, 61% of stand downs were immediate dispatches (HEMS is deployed on initial information received) compared to the 30% that were sent after interrogation (more information is gathered). Most stand downs occurred at night (19:01 07:00) and there were peaks at paramedic shift change overs (07:00 19:00). Conclusion Improving the quality of initial information could improve tasking accuracy and hence reduce stand downs. The improvements are two-fold with more tasking training for staff and development of the dispatch criteria.