United States Special Operations Command fatality study of subcommands, units, and trends.

BACKGROUND: Death from injury occurs predominantly in prehospital settings. Injury prevention and prehospital care of military forces is the responsibility of combatant commanders. Medical examiner and trauma systems should routinely study fatalities and inform commanders of mortality trends. METHODS: Data reported on US Special Operations Command (USSOCOM) fatalities who died while performing duties from September 11, 2001, to September 10, 2018, were reevaluated to compare subcommands, units, and trends. Injury was assessed by mechanism, severity, operational posture, and survivability. Death was assessed by manner, cause, classification, mechanism, and preventability. RESULTS: Of 614 USSOCOM fatalities (median age, 30 years; male, 98.5%), 67.6% occurred in the Army command, of which 49.2% occurred in the Special Forces command. Battle injury accounted for 60.1% of USSOCOM fatalities. Most battle-injured fatalities in each subcommand had nonsurvivable injuries and nonpreventable deaths. For each subcommand except Marine Corps, fatalities with nonsurvivable injuries sustained injuries primarily while mounted. By subcommand, the primary cause of death for fatalities with nonsurvivable injuries was blast for Army (57.6%), multiple/blunt force for Navy (60.0%), gunshot wound for Air Force (55.6%), and split between blast (50.0%) and gunshot wound (50.0%) for Marine Corps. For each subcommand except Air Force, fatalities with potentially survivable-survivable injuries sustained injuries primarily while dismounted, and the mechanism of death was primarily hemorrhage plus other mechanism or hemorrhage alone. Hemorrhage only mechanism of death was surpassed over time by complex multimechanism death. Potential for injury survivability and death preventability was greatest during early and later years of conflict. CONCLUSION: Organizational differences in mortality characteristics and trends were identified from which commanders can refine efforts to prevent and treat injury and improve survival. Fatality analyses inform operational risk matrices and advance casualty prevention and response efforts. Prevention, assessment, and treatment strategies must evolve to reduce death from hemorrhage plus coexisting mechanisms. LEVEL OF EVIDENCE: Performance Improvement and Epidemiological, level IV