Time and place of death from automobile crashes: Research endpoint implications.

BACKGROUND: Vehicle crashes are a leading cause of US injury and death. Early death, however, has almost entirely been studied in-hospital. The US Department of Transportation Fatality Analysis Reporting System (FARS) database captures both prehospital and in-hospital mortality. METHODS: FARS location (prehospital, in-hospital) and time of death were reviewed (1978-2013), and a 2003-2005 subgroup of 55,537 early deaths (i.e., between 5 minutes and 4 hours after injury) was analyzed to quantify risk of death over time. RESULTS: There has been an overall decrease in 1978-2013 US vehicle-related deaths (from 3.3 deaths per 100 million vehicle miles traveled to 1.1 and from 22.6 per 100,000 population to 10.4). Snapshots of the death data reveal an overall downward trend of total in-hospital and prehospital deaths. The proportion of hospital deaths decreased by 58%, whereas the proportion of deaths in the prehospital period increased to 56%. Subgroup analysis revealed a rate of mortality risk of 0.4% per minute for the first 30 minutes, 1% per minute for the next 60 minutes, and 0.2% per minute and plateauing thereafter. CONCLUSIONS: Analysis of census FARS data of motor vehicle crash-related deaths showed an overall 35% decrease in mortality over a period of 36 years. The disproportionate reduction in in-hospital deaths is perhaps a testament to the effectiveness of trauma centers. However, there is a demonstrable need to focus on prehospital deaths with resuscitative and adjuvant therapy research and trauma system design. Quantifying risk of death over time should help focus emergency medical services, trauma system, and resuscitation goals. LEVEL OF EVIDENCE: Epidemiologic study, level III.

Multi-Injury Casualty Stream Simulation in a Shipboard Combat Environment.

Accurate forecasts of casualty streams are essential for estimating personnel and materiel requirements for future naval combat engagements. The scarcity of recent naval combat data makes accurate forecasting difficult. Furthermore, current forecasts are based on single injuries only, even though empirical evidence indicates most battle casualties suffer multiple injuries. These anticipated single-injury casualty streams underestimate the needed medical resources. This article describes a method of simulating realistic multi-injury casualty streams in a maritime environment by combining available shipboard data with ground combat blast data. The simulations, based on the Military Combat Injury Scale, are expected to provide a better tool for medical logistics planning.

Combat injury coding: a review and reconfiguration.

BACKGROUND: The current civilian Abbreviated Injury Scale (AIS), designed for automobile crash injuries, yields important information about civilian injuries. It has been recognized for some time, however, that both the AIS and AIS-based scores such as the Injury Severity Score (ISS) are inadequate for describing penetrating injuries, especially those sustained in combat. Existing injury coding systems do not adequately describe (they actually exclude) combat injuries such as the devastating multi-mechanistic injuries resulting from attacks with improvised explosive devices (IEDs). METHODS: After quantifying the inapplicability of current coding systems, the Military Combat Injury Scale (MCIS), which includes injury descriptors that accurately characterize combat anatomic injury, and the Military Functional Incapacity Scale (MFIS), which indicates immediate tactical functional impairment, were developed by a large tri-service military and civilian group of combat trauma subject-matter experts. Assignment of MCIS severity levels was based on urgency, level of care needed, and risk of death from each individual injury. The MFIS was developed based on the casualty's ability to shoot, move, and communicate, and comprises four levels ranging from "Able to continue mission" to "Lost to military." Separate functional impairments were identified for injuries aboard ship. Preliminary evaluation of MCIS discrimination, calibration, and casualty disposition was performed on 992 combat-injured patients using two modeling processes. RESULTS: Based on combat casualty data, the MCIS is a new, simpler, comprehensive severity scale with 269 codes (vs. 1999 in AIS) that specifically characterize and distinguish the many unique injuries encountered in combat. The MCIS integrates with the MFIS, which associates immediate combat functional impairment with minor and moderate-severity injuries. Predictive validation on combat datasets shows improved performance over AIS-based tools in addition to improved face, construct, and content validity and coding inter-rater reliability. Thus, the MCIS has greater relevance, accuracy, and precision for many military-specific applications. CONCLUSION: Over a period of several years, the Military Combat Injury Scale and Military Functional Incapacity Scale were developed, tested and validated by teams of civilian and tri-service military expertise. MCIS shows significant promise in documenting the nature, severity and complexity of modern combat injury.

Improved characterization of combat injury.

BACKGROUND: Combat injury patterns differ from civilian trauma in that the former are largely explosion-related, comprising multiple mechanistic and fragment injuries and high-kinetic-energy bullets. Further, unlike civilians, U.S. armed forces combatants are usually heavily protected with helmets and Kevlar body armor with ceramic plate inserts. Searchable databases providing actionable, statistically valid knowledge of body surface entry wounds and resulting organ injury severity are essential to understanding combat trauma. METHODS: Two tools were developed to address these unique aspects of combat injury: (1) the Surface Wound Mapping (SWM) database and Surface Wound Analysis Tool (SWAT) software that were developed to generate 3D density maps of point-of-surface wound entry and resultant anatomic injury severity; and (2) the Abbreviated Injury Scale (AIS) 2005-Military that was developed by a panel of military trauma surgeons to account for multiple injury etiology from explosions and other high-kinetic- energy weapons. Combined data from the Joint Theater Trauma Registry, Navy/Marine Combat Trauma Registry, and the Armed Forces Medical Examiner System Mortality Trauma Registry were coded in AIS 2005-Military, entered into the SWM database, and analyzed for entrance site and wounding path. RESULTS: When data on 1,151 patients, who had a total of 3,500 surface wounds and 12,889 injuries, were entered into SWM, surface wounds averaged 3.0 per casualty and injuries averaged 11.2 per casualty. Of the 3,500 surface wounds, 2,496 (71%) were entrance wounds with 6,631 (51%) associated internal injuries, with 2.2 entrance wounds and 5.8 associated injuries per casualty (some details cannot be given because of operational security). Crude deaths rates were calculated using Maximum AIS-Military. CONCLUSION: These new tools have been successfully implemented to describe combat injury, mortality, and distribution of wounds and associated injuries. AIS 2005-Military is a more precise assignment of severity to military injuries. SWM has brought data from all three combat registries together into one analyzable database. SWM and SWAT allow visualization of wounds and associated injuries by region on a 3D model of the body.

Injury severity and causes of death from Operation Iraqi Freedom and Operation Enduring Freedom: 2003-2004 versus 2006.

BACKGROUND: The opinion that injuries sustained in Iraq and Afghanistan have increased in severity is widely held by clinicians who have deployed multiple times. To continuously improve combat casualty care, the Department of Defense has enacted numerous evidence-based policies and clinical practice guidelines. We hypothesized that the severity of wounds has increased over time. Furthermore, we examined cause of death looking for opportunities of improvement for research and training. METHODS: Autopsies of the earliest combat deaths from Iraq and Afghanistan and the latest deaths of 2006 were analyzed to assess changes in injury severity and causes of death. Fatalities were classified as nonsurvivable (NS) or potentially survivable (PS). PS deaths were then reviewed in depth to analyze mechanism and cause. RESULTS: There were 486 cases from March 2003 to April 2004 (group 1) and 496 from June 2006 to December 2006 (group 2) that met inclusion criteria. Of the PS fatalities (group 1: 93 and group 2: 139), the injury severity score was lower in the first group (27 +/- 14 vs. 37 +/- 16, p < 0.001), and had a lower number of abbreviated injury scores >or=4 (1.1 +/- 0.79 vs. 1.5 +/- 0.83 per person, p < 0.001). The main cause of death in the PS fatalities was truncal hemorrhage (51% vs. 49%, p = NS). Deaths per month between groups doubled (35 vs. 71), whereas the case fatality rates between the two time periods were equivalent (11.0 vs. 9.8, p = NS). DISCUSSION: In the time periods of the war studied, deaths per month has doubled, with increases in both injury severity and number of wounds per casualty. Truncal hemorrhage is the leading cause of potentially survivable deaths. Arguably, the success of the medical improvements during this war has served to maintain the lowest case fatality rate on record.

Causes of death in US Special Operations Forces in the global war on terrorism: 2001-2004.

INTRODUCTION: Effective combat trauma management strategies depend on an understanding of the epidemiology of death on the battlefield, resulting in evidence-based equipment, training, and research requirements. METHODS: All Special Operations Forces (SOF) fatalities (combat and noncombat) in Operation Iraqi Freedom/Operation Enduring Freedom (OEF/OIF) from October 2001 until November 2004 were reviewed. All available autopsy and treatment records and photographs were used. In most cases, the immediate tactical situation was unknown. The review was performed by a multidisciplinary group including forensic pathologists, an SOF combat medic, and trauma surgeons. Fatalities were classified as having wounds that were either nonsurvivable or potentially survivable with existing training, equipment, and expertise on the battlefield. A structured review was performed evaluating the need for new equipment, training, or research requirements. Results were compared to autopsy data from Vietnam and modern civilian trauma center data. The study was approved by the Institutional Review Boards of the Armed Forces Institute of Pathology and the US Army Institute of Surgical Research. RESULTS: During the study period, 82 SOF fatalities were identified. Autopsies were performed on 77 Soldiers. Five casualties died secondary to aircraft crash, their bodies were not recovered from the ocean. For the purposes of this study they were considered nonsurvivable. Eighty-five percent (n = 70) of the fatalities sustained wounds that were nonsurvivable, while the remaining 15% (n = 12) had wounds that were potentially survivable. Injury Severity Score (ISS) was higher in the nonsurvivable group (p < 0.05). Truncal hemorrhage accounted for 47% of deaths while extremity hemorrhage accounted for 33%. One casualty was noted at autopsy to have a tension pneumothorax as well as multiple sources of internal hemorrhage, one suffered an airway death, while another died of sepsis 56 days after injury. Of those casualties deemed to be nonsurvivable, there were 31 patients with 40 Abbreviated Injury Score (AIS) 6 injuries (p = .0011), and 53 patients with 104 AIS 5 injuries. Among the 12 deaths deemed to be potentially survivable, there were only 8 AIS 5 injuries. Deaths were largely caused by explosions (n = 35), gunshot wounds (n = 23), and aircraft accidents (n = 19). No new training or equipment needs were identified for 53% of the potentially survivable deaths while improved methods of truncal hemorrhage control need to be developed for the remainder. The review panel concluded that 85% of the deaths would not have been prevented at a civilian Level I facility. Available records, in most cases, did not contain information about the use of body armor, time to death after injury, or the ongoing tactical situation. CONCLUSIONS: The majority of deaths on the modern battlefield are nonsurvivable. Current results are not different from previous conflicts. In Vietnam, reported potentially preventable death rates range from 5% to 35% and civilian data reports potentially preventable death rates ranging from 12% to 22%. Military munitions cause multiple lethal injuries. Current trauma training and equipment is sufficient to care for 53% of the potentially survivable deaths. Improved methods of intravenous or intracavitary noncompressible hemostasis combined with rapid surgery are required for the remaining 47% of the decedents.