Association of Prehospital Neck Wound Survivability and Battlefield Medical Evacuation Time in Afghanistan.

Abstract

The U.S. Military's Golden Hour policy led to improved warfighter survivability during the Global War on Terror. The policy's success is well-documented, but a categorical evaluation and stratification of medical evacuation (MEDEVAC) times based on combat injury is lacking. We queried the Department of Defense Joint Trauma System Prehospital Trauma Registry for casualties with documented penetrating neck trauma in Afghanistan requiring battlefield MEDEVAC from June 15, 2009, through February 1, 2021. Casualties were excluded if the time from the point of injury to reach higher level medical care was not documented, listed as zero, or exceeded 4 hours. They were also excluded if demographic data were incomplete or deemed unreliable or if their injuries occurred outside of Afghanistan.We designed a logistic regression model to test for associations in survivability, adjusting for composite injury severity score, patient age group, and type of next higher level of care reached. We then used our model to interpolate MEDEVAC times associated with 0.1%, 1%, and 10% increased risk of death for an incapacitated casualty with penetrating neck trauma. Of 1,147 encounters, 444 casualties met inclusion criteria. Of these casualties, 430 (96.9%) survived to discharge. Interpolative analysis of our multivariable logistic regression model showed that MEDEVAC times ≥8 minutes, ≥53 minutes, and ≥196 minutes are associated with a 0.1%, 1%, and 10% increased risk of mortality from baseline, respectively. Our data characterize the maximum MEDEVAC times associated with 0.1%, 1%, and 10% increased risk of death from baseline survivability for penetrating battlefield neck trauma in Afghanistan.