BACKGROUND: The US Army pioneered medical evacuation (MEDEVAC) by helicopter, yet its system remains essentially unchanged since the Vietnam era. Care is provided by a single combat medic credentialed at the Emergency Medical Technician – Basic level. Treatment protocols, documentation, medical direction, and quality improvement processes are not standardized and vary significantly across US Army helicopter evacuation units. This is in contrast to helicopter emergency medical services that operate within the United States. Current civilian helicopter evacuation platforms are routinely staffed by critical care–trained flight paramedics (CCFP) or comparably trained flight nurses who operate under trained EMS physician medical direction using formalized protocols, standardized patient care documentation, and rigorous quality improvement processes. This study compares mortality of patients with injury from trauma between the US Army’s standard helicopter evacuation system staffed with medics at the Emergency Medical Technician – Basic level (standard MEDEVAC) and one staffed with experienced CCFP using adopted civilian helicopter emergency medical services practices.
METHODS: This is a retrospective study of a natural experiment. Using data from the Joint Theater Trauma Registry, 48-hour mortality for severely injured patients (injury severity score ≥ 16) was compared between patients transported by standard MEDEVAC units and CCFP air ambulance units.
RESULTS: The 48-hour mortality for the CCFP-treated patients was 8% compared to 15% for the standard MEDEVAC patients. After adjustment for covariates, the CCFP system was associated with a 66% lower estimated risk of 48-hour mortality compared to the standard MEDEVAC system.
CONCLUSIONS: These findings demonstrate that using an air ambulance system based on modern civilian helicopter EMS practice was associated with a lower estimated risk of 48-hour mortality among severely injured patients in a combat setting.
LEVEL OF EVIDENCE: Therapeutic study, level II.
From the US Army Institute of Surgical Research (R.L.M., A.A., J.P., J.A.O., R.T.G., W.C.D.), Fort Sam Houston, San Antonio, Texas.
The opinions or assertions expressed herein are the views of the authors and are not to be construed as official or as reflecting the views of the US Army or the US Department of Defense.
This work was presented at the Advanced Technology Applications for Combat Casualty Care Conference in Fort Lauderdale, Florida, August 15–18, 2011.
Address for reprints: Robert L. Mabry, MD, MC, US Army Institute of Surgical Research, 3400 Rawley E. Chambers Ave, MCMR-SRJ, Fort Sam Houston, San Antonio, TX 78234-6315; email: firstname.lastname@example.org.