Incidence and epidemiology of combat injuries sustained during "the surge" portion of operation iraqi freedom by a U.S. army brigade combat team

Background: A prospective, longitudinal analysis of injuries sustained by a large combat-deployed maneuver unit has not been previously performed. Methods: A detailed description of the combat casualty care statistics, distribution of wounds, and mechanisms of injury incurred by a U.S. Army Brigade Combat Team during "The Surge" phase of Operation Iraqi Freedom was performed using a centralized casualty database and an electronic medical record system. Results: Among the 4,122 soldiers deployed, there were 500 combat wounds in 390 combat casualties. The combat casualty rate for the Brigade Combat Team was 75.7 per 1,000 soldier combat-years. The % killed in action (KIA) was 22.1%, and the %died of wounds was 3.2%. The distribution of these wounds was as follows: head/neck 36.2%, thorax 7.5%, abdomen 6.9%, and extremities 49.4%. The percentage of combat wounds showed a significant increase in the head/neck region (p < 0.0001) and a decrease in the extremities (p < 0.03) compared with data from World War II, Korea, and Vietnam. The percentage of thoracic wounds (p < 0.03) was significantly less than historical data from World War II and Vietnam. The %KIA was significantly greater in those soldiers injured by an explosion (26.3%) compared with those soldiers injured by a gunshot wound (4.6%; p = 0.003). Improvised explosive devices accounted for 77.7% of all combat wounds. Conclusions: There was a significantly higher proportion of head/neck wounds compared with previous U.S. conflicts. The 22.1% KIA was comparable with previous U.S. conflicts despite improvements in individual/vehicular body armor and is largely attributable to the lethality of improvised explosive devices. The lethality of a gunshot wound in Operation Iraqi Freedom has decreased to 4.6% with the use of individual body armor.