Introduction: Helicopter Emergency Medical Services (HEMS) is lifesaving but can itself lead to serious or fatal accidents. Current research is limited to descriptions of accidents, but the specifics of casualties and injuries are unavailable. This study aimed to detail mortality and injury patterns and examine associations with casualties involved. Methods: The study was a retrospective database and chart review of HEMS accidents from the National Transportation Safety Board database from 2013 to 2022. Accident charts were hand-searched, and details of flight, crew, patients, and injuries were manually extracted using a predefined form. Injuries from serious accidents were categorized by type and Anatomic Profile (AP) (Category A = head and spinal cord, Category B = thorax and anterior neck, Category C = remaining serious, Category D = non-serious injuries). Results: Of 72 total HEMS accidents, 28 (38.9%) resulted in at least serious (27) or fatal (45) injuries. These flights carried a total of 10 patients with 84 crew, of whom 5 (50%) patients and 40 (47.6%) crew died. Most accidents occurred without patients aboard (18, 64.3%). However, when aboard, patients were as vulnerable to fatal injury as crew (OR 1.10, 95% CI 0.30-4.08). Injury patterns were most often axial (13, 12.4%) and extremity fractures (6, 5.7%), burns (6, 5.7%), axial (4, 3.8%) and extremity blunt trauma (2, 1.9%), and hemopneumothoraces (2, 1.9%). AP of injuries were A in 7 (6.7%), B in 8 (7.6%), C in 15 (14.3%), D in 13 (12.4%). Causes of death were skull, spine, and chest fractures, burns, hemothorax, intra-abdominal lacerations, lower limb amputation, smoke inhalation, hypothermia, and an acute cardiac event. Conclusion: HEMS accidents were lethal to both crew and patients. Fatal injuries included fractures of the skull and spine, burns, and visceral lacerations. Mortality and injury patterns identified in this study can inform HEMS mitigation measures and treatment preparation for responders.
Teo et al. (Sun,) studied this question.