Hoist missions and seasonal influences on air rescue service helicopters: A descriptive study based on three German helicopters (preprint)

ABSTRACT

Background In the German emergency medical services, 67 rescue helicopters and 12 helicopters for rescue and intensive care transport missions provide their services mostly under visual flight conditions. Of these, 10 helicopters are equipped with a rescue hoist. There is limited data on the frequency of hoist operations, tracer diagnoses, and influences such as weather and vacation periods. This study examines hoist deployment frequencies, tracer diagnostics, and the influence of vacation season at three German helicopter sites.Methods In the period from 01 Feb. 2018 to 31 Dec. 2021, a total of 1340 hoist missions were retrospectively examined descriptively for the helicopters Christoph 15 (n = 196), Christoph 1 (n = 316), and Christoph Murnau (n = 828) using their electronic mission documentation.Results 56.89% of the hoist missions were flown during the summer months, with vacation periods having a small effect on Christoph 1 only. Traumatological diagnoses clearly predominated on all three helicopters, with 75.0% on Christoph 15, 78.8% on Christoph 1, and 52.17% on Christoph Murnau. Among the traumatological indications, extremity trauma (39.29%) was the most frequent, followed by spinal injuries (10.71%), traumatic brain injuries (8.67%), and polytrauma (4.59%). Among internal medicine emergencies, collapse/syncope (5.61%) and cardiovascular arrest (3.06%) were the most common, followed by acute coronary syndromes, anaphylaxis, and hypothermia (2.55% each).Conclusions Despite the predominance of extremity injuries and syncope/collapse, where risk stratification was the primary concern and complex medical care was usually not required, there were also dynamic and complex emergency events, e.g., cardiovascular arrests, traumatic brain injuries, and anaphylaxis. Not even the Covid-19 pandemic led to a significant shift in distribution. Surprisingly, the influence of vacation periods on the frequency of operations was less pronounced even in tourism-oriented regions. For future research, other aspects need to be studied, such as the impact of severe weather on helicopter operations in the context of climate change, as well as personnel strategy (e.g., 3-person vs. 4-person crews).