IMPORTANCE: The term golden hour was coined to encourage urgency of trauma care. In 2009, Secretary of Defense Robert M. Gates mandated prehospital helicopter transport of critically injured combat ...casualties in 60 minutes or less. OBJECTIVES: To compare morbidity and mortality outcomes for casualties before vs after the mandate and for those who underwent prehospital helicopter transport in 60 minutes or less vs more than 60 minutes. DESIGN, SETTING, AND PARTICIPANTS: A retrospective descriptive analysis of battlefield data examined 21 089 US military casualties that occurred during the Afghanistan conflict from September 11, 2001, to March 31, 2014. Analysis was conducted from September 1, 2014, to January 21, 2015. MAIN OUTCOMES AND MEASURES: Data for all casualties were analyzed according to whether they occurred before or after the mandate. Detailed data for those who underwent prehospital helicopter transport were analyzed according to whether they occurred before or after the mandate and whether they occurred in 60 minutes or less vs more than 60 minutes. Casualties with minor wounds were excluded. Mortality and morbidity outcomes and treatment capability–related variables were compared. RESULTS: For the total casualty population, the percentage killed in action (16.0% 386 of 2411 vs 9.9% 964 of 9755; P < .001) and the case fatality rate (CFR 13.7 469 of 3429 vs 7.6 1344 of 17 660; P < .001) were higher before vs after the mandate, while the percentage died of wounds (4.1% 83 of 2025 vs 4.3% 380 of 8791; P = .71) remained unchanged. Decline in CFR after the mandate was associated with an increasing percentage of casualties transported in 60 minutes or less (regression coefficient, –0.141; P < .001), with projected vs actual CFR equating to 359 lives saved. Among 4542 casualties (mean injury severity score, 17.3; mortality, 10.1% 457 of 4542) with detailed data, there was a decrease in median transport time after the mandate (90 min vs 43 min; P < .001) and an increase in missions achieving prehospital helicopter transport in 60 minutes or less (24.8% 181 of 731 vs 75.2% 2867 of 3811; P < .001). When adjusted for injury severity score and time period, the percentage killed in action was lower for those critically injured who received a blood transfusion (6.8% 40 of 589 vs 51.0% 249 of 488; P < .001) and were transported in 60 minutes or less (25.7% 205 of 799 vs 30.2% 84 of 278; P < .01), while the percentage died of wounds was lower among those critically injured initially treated by combat support hospitals (9.1% 48 of 530 vs 15.7% 86 of 547; P < .01). Acute morbidity was higher among those critically injured who were transported in 60 minutes or less (36.9% 295 of 799 vs 27.3% 76 of 278; P < .01), those severely and critically injured initially treated at combat support hospitals (severely injured, 51.1% 161 of 315 vs 33.1% 104 of 314; P < .001; and critically injured, 39.8% 211 of 530 vs 29.3% 160 of 547; P < .001), and casualties who received a blood transfusion (50.2% 618 of 1231 vs 3.7% 121 of 3311; P < .001), emphasizing the need for timely advanced treatment. CONCLUSIONS AND RELEVANCE: A mandate made in 2009 by Secretary of Defense Gates reduced the time between combat injury and receiving definitive care. Prehospital transport time and treatment capability are important factors for casualty survival on the battlefield.
IMPORTANCE: Prehospital blood product transfusion in trauma care remains controversial due to poor-quality evidence and cost. Sequential expansion of blood transfusion capability after 2012 to ...deployed military medical evacuation (MEDEVAC) units enabled a concurrent cohort study to focus on the timing as well as the location of the initial transfusion. OBJECTIVE: To examine the association of prehospital transfusion and time to initial transfusion with injury survival. DESIGN, SETTING, AND PARTICIPANTS: Retrospective cohort study of US military combat casualties in Afghanistan between April 1, 2012, and August 7, 2015. Eligible patients were rescued alive by MEDEVAC from point of injury with either (1) a traumatic limb amputation at or above the knee or elbow or (2) shock defined as a systolic blood pressure of less than 90 mm Hg or a heart rate greater than 120 beats per minute. EXPOSURES: Initiation of prehospital transfusion and time from MEDEVAC rescue to first transfusion, regardless of location (ie, prior to or during hospitalization). Transfusion recipients were compared with nonrecipients (unexposed) for whom transfusion was delayed or not given. MAIN OUTCOMES AND MEASURES: Mortality at 24 hours and 30 days after MEDEVAC rescue were coprimary outcomes. To balance injury severity, nonrecipients of prehospital transfusion were frequency matched to recipients by mechanism of injury, prehospital shock, severity of limb amputation, head injury, and torso hemorrhage. Cox regression was stratified by matched groups and also adjusted for age, injury year, transport team, tourniquet use, and time to MEDEVAC rescue. RESULTS: Of 502 patients (median age, 25 years interquartile range, 22 to 29 years; 98% male), 3 of 55 prehospital transfusion recipients (5%) and 85 of 447 nonrecipients (19%) died within 24 hours of MEDEVAC rescue (between-group difference, −14% 95% CI, −21% to −6%; P = .01). By day 30, 6 recipients (11%) and 102 nonrecipients (23%) died (between-group difference, −12% 95% CI, −21% to −2%; P = .04). For the 386 patients without missing covariate data among the 400 patients within the matched groups, the adjusted hazard ratio for mortality associated with prehospital transfusion was 0.26 (95% CI, 0.08 to 0.84, P = .02) over 24 hours (3 deaths among 54 recipients vs 67 deaths among 332 matched nonrecipients) and 0.39 (95% CI, 0.16 to 0.92, P = .03) over 30 days (6 vs 76 deaths, respectively). Time to initial transfusion, regardless of location (prehospital or during hospitalization), was associated with reduced 24-hour mortality only up to 15 minutes after MEDEVAC rescue (median, 36 minutes after injury; adjusted hazard ratio, 0.17 95% CI, 0.04 to 0.73, P = .02; there were 2 deaths among 62 recipients vs 68 deaths among 324 delayed transfusion recipients or nonrecipients). CONCLUSIONS AND RELEVANCE: Among medically evacuated US military combat causalities in Afghanistan, blood product transfusion prehospital or within minutes of injury was associated with greater 24-hour and 30-day survival than delayed transfusion or no transfusion. The findings support prehospital transfusion in this setting.
IMPORTANCE: Although the Afghanistan and Iraq conflicts have the lowest US case-fatality rates in history, no comprehensive assessment of combat casualty care statistics, major interventions, or risk ...factors has been reported to date after 16 years of conflict. OBJECTIVES: To analyze trends in overall combat casualty statistics, to assess aggregate measures of injury and interventions, and to simulate how mortality rates would have changed had the interventions not occurred. DESIGN, SETTING, AND PARTICIPANTS: Retrospective analysis of all available aggregate and weighted individual administrative data compiled from Department of Defense databases on all 56 763 US military casualties injured in battle in Afghanistan and Iraq from October 1, 2001, through December 31, 2017. Casualty outcomes were compared with period-specific ratios of the use of tourniquets, blood transfusions, and transport to a surgical facility within 60 minutes. MAIN OUTCOMES AND MEASURES: Main outcomes were casualty status (alive, killed in action KIA, or died of wounds DOW) and the case-fatality rate (CFR). Regression, simulation, and decomposition analyses were used to assess associations between covariates, interventions, and individual casualty status; estimate casualty transitions (KIA to DOW, KIA to alive, and DOW to alive); and estimate the contribution of interventions to changes in CFR. RESULTS: In aggregate data for 56 763 casualties, CFR decreased in Afghanistan (20.0% to 8.6%) and Iraq (20.4% to 10.1%) from early stages to later stages of the conflicts. Survival for critically injured casualties (Injury Severity Score, 25-75 critical) increased from 2.2% to 39.9% in Afghanistan and from 8.9% to 32.9% in Iraq. Simulations using data from 23 699 individual casualties showed that without interventions assessed, CFR would likely have been higher in Afghanistan (15.6% estimated vs 8.6% observed) and Iraq (16.3% estimated vs 10.1% observed), equating to 3672 additional deaths (95% CI, 3209-4244 deaths), of which 1623 (44.2%) were associated with the interventions studied: 474 deaths (12.9%) (95% CI, 439-510) associated with the use of tourniquets, 873 (23.8%) (95% CI, 840-910) with blood transfusion, and 275 (7.5%) (95% CI, 259-292) with prehospital transport times. CONCLUSIONS AND RELEVANCE: Our analysis suggests that increased use of tourniquets, blood transfusions, and more rapid prehospital transport were associated with 44.2% of total mortality reduction. More critically injured casualties reached surgical care, with increased survival, implying improvements in prehospital and hospital care.
Most combat casualties who die, do so in the prehospital setting. Efforts directed toward alleviating prehospital combat trauma death, known as killed in action (KIA) mortality, have the greatest ...opportunity for eliminating preventable death.
Four thousand five hundred forty-two military casualties injured in Afghanistan from September 11, 2001, to March 31, 2014, were included in this retrospective analysis to evaluate proposed explanations for observed KIA reduction after a mandate by Secretary of Defense Robert M. Gates that transport of injured service members occur within 60 minutes. Using inverse probability weighting to account for selection bias, data were analyzed using multivariable logistic regression and simulation analysis to estimate the effects of (1) gradual improvement, (2) damage control resuscitation, (3) harm from inadequate resources, (4) change in wound pattern, and (5) transport time on KIA mortality.
The effect of gradual improvement measured as a time trend was not significant (adjusted odds ratio AOR, 0.99; 95% confidence interval CI, 0.94-1.03; p = 0.58). For casualties with military Injury Severity Score of 25 or higher, the odds of KIA mortality were 83% lower for casualties who needed and received prehospital blood transfusion (AOR, 0.17; 95% CI, 0.06-0.51; p = 0.002); 33% lower for casualties receiving initial treatment by forward surgical teams (AOR, 0.67; 95% CI, 0.58-0.78; p < 0.001); 70%, 74%, and 87% lower for casualties with dominant injuries to head (AOR, 0.30; 95% CI, 0.23-0.38; p < 0.001), abdomen (AOR, 0.26, 95% CI, 0.19-0.36; p < 0.001) and extremities (AOR, 0.13; 95% CI, 0.09-0.17; p < 0.001); 35% lower for casualties categorized with blunt injuries (AOR, 0.65; 95% CI, 0.46-0.92; p = 0.01); and 39% lower for casualties transported within one hour (AOR, 0.61; 95% CI, 0.51-0.74; p < 0.001). Results of simulations in which transport times had not changed after the mandate indicate that KIA mortality would have been 1.4% higher than observed, equating to 135 more KIA deaths (95% CI, 105-164).
Reduction in KIA mortality is associated with early treatment capabilities, blunt mechanism, select body locations of injury, and rapid transport.
Therapy, level III.
To examine time from injury to initiation of surgical care and association with survival in US military casualties.
Although the advantage of trauma care within the "golden hour" after an injury is ...generally accepted, evidence is scarce.
This retrospective, population-based cohort study included US military casualties injured in Afghanistan and Iraq, January 2007 to December 2015, alive at initial request for evacuation with maximum abbreviated injury scale scores ≥2 and documented 30-day survival status after injury. Interventions: (1) handoff alive to the surgical team, and (2) initiation of first surgery were analyzed as time-dependent covariates (elapsed time from injury) using sequential Cox proportional hazards regression to assess how intervention timing might affect mortality. Covariates included age, injury year, and injury severity.
Among 5269 patients (median age, 24 years; 97% males; and 68% battle-injured), 728 died within 30 days of injury, 68% within 1 hour, and 90% within 4 hours. Only handoffs within 1 hour of injury and the resultant timely initiation of emergency surgery (adjusted also for prior advanced resuscitative interventions) were significantly associated with reduced 24-hour mortality compared with more delayed surgical care (adjusted hazard ratios: 0.34; 95% CI: 0.14-0.82; P = 0.02; and 0.40; 95% CI: 0.20-0.81; P = 0.01, respectively). In-hospital waits for surgery (mean: 1.1 hours; 95% CI; 1.0-1.2) scarcely contributed ( P = 0.67).
Rapid handoff to the surgical team within 1 hour of injury may reduce mortality by 66% in US military casualties. In the subgroup of casualties with indications for emergency surgery, rapid handoff with timely surgical intervention may reduce mortality by 60%. To inform future research and trauma system planning, findings are pivotal.
Comprehensive analyses of battle-injured fatalities, incorporating a multidisciplinary process with a standardized lexicon, is necessary to elucidate opportunities for improvement (OFIs) to increase ...survivability.
A mortality review was conducted on United States Special Operations Command battle-injured fatalities who died from September 11, 2001, to September 10, 2018. Fatalities were analyzed by demographics, operational posture, mechanism of injury, cause of death, mechanism of death (MOD), classification of death, and injury severity. Injury survivability was determined by a subject matter expert panel and compared with injury patterns among Department of Defense Trauma Registry survivors. Death preventability and OFI were determined for fatalities with potentially survivable or survivable (PS-S) injuries using tactical data and documented medical interventions.
Of 369 United States Special Operations Command battle-injured fatalities (median age, 29 years; male, 98.6%), most were killed in action (89.4%) and more than half died from injuries sustained during mounted operations (52.3%). The cause of death was blast injury (45.0%), gunshot wound (39.8%), and multiple/blunt force injury (15.2%). The leading MOD was catastrophic tissue destruction (73.7%). Most fatalities sustained nonsurvivable injuries (74.3%). For fatalities with PS-S injuries, most had hemorrhage as a component of MOD (88.4%); however, the MOD was multifactorial in the majority of these fatalities (58.9%). Only 5.4% of all fatalities and 21.1% of fatalities with PS-S injuries had comparable injury patterns among survivors. Accounting for tactical situation, a minority of deaths were potentially preventable (5.7%) and a few preventable (1.1%). Time to surgery (93.7%) and prehospital blood transfusion (89.5%) were the leading OFI for PS-S fatalities. Most fatalities with PS-S injuries requiring blood (83.5%) also had an additional prehospital OFI.
Comprehensive mortality reviews of battlefield fatalities can identify OFI in combat casualty care and prevention. Standardized lexicon is essential for translation to civilian trauma systems.
Epidemiological, level IV.
ABSTRACT
Background
The battalion aid station (BAS) has historically served as the first stop during which combat casualties would receive care beyond a combat medic. Since the conflicts in Iraq and ...Afghanistan, many combat casualties have bypassed the BAS for treatment facilities capable of surgery. We describe the care provided at these treatment facilities during 2007–2020.
Methods
This is a secondary analysis of previously described data from the Department of Defense Trauma Registry. We included encounters with the documentation of an assessment or intervention at a BAS or forward operating base from January 1, 2007 to March 17, 2020. We utilized descriptive statistics to characterize these encounters.
Results
There were 28,950 encounters in our original dataset, of which 3.1% (884) had the documentation of a prehospital visit to a BAS. The BAS cohort was older (25 vs. 24, P < .001) The non-BAS cohort saw a larger portion of pediatric (<18 years) patients (10.7% vs. 5.7%, P < .001). A higher proportion of BAS patients had nonbattle injuries (40% vs. 20.7%, P < .001). The mean injury severity score was higher in the non-BAS cohort (9 vs. 5, P < .001). A higher proportion of the non-BAS cohort had more serious extremity injuries (25.1% vs. 18.4%, P < .001), although the non-BAS cohort had a trend toward serious injuries to the abdomen (P = .051) and thorax (P = .069). There was no difference in survival.
Conclusions
The BAS was once a critical point in casualty evacuation and treatment. Within our dataset, the overall number of encounters that involved a stop at a BAS facility was low. For both the asymmetric battlefield and multidomain operations/large-scale combat operations, the current model would benefit from a more robust capability to include storage of blood, ventilators, and monitoring and hold patients for an undetermined amount of time.
Reducing time from injury to care can optimize trauma patient outcomes. A previous study of prehospital transport of US military casualties during the Afghanistan conflict demonstrated the importance ...of time and treatment capability for combat casualty survival.
A retrospective descriptive analysis was conducted to analyze battlefield data collected on US military combat casualties during the Iraq conflict from March 19, 2003, to August 31, 2010. All casualties were analyzed by mortality outcome (killed in action, died of wounds, case fatality rate) and compared with Afghanistan conflict. Detailed data for those who underwent prehospital transport were analyzed for effects of transport time, injury severity, and blood transfusion on survival.
For the total population, percent killed in action (16.6% vs. 11.1%), percent died of wounds (5.9% vs. 4.3%), and case fatality rate (10.0 vs. 8.6) were higher for Iraq versus Afghanistan (p < 0.001). Among 1,692 casualties (mean New Injury Severity Score, 22.5; mortality, 17.6%) with detailed data, the injury mechanism included 77.7% from explosions and 22.1% from gunshot wounds. For prehospital transport, 67.6% of casualties were transported within 60 minutes, and 32.4% of casualties were transported in greater than 60 minutes. Although 97.0% of deaths occurred in critical casualties (New Injury Severity Score, 25-75), 52.7% of critical casualties survived. Critical casualties were transported more rapidly (p < 0.01) and more frequently within 60 minutes (p < 0.01) than other casualties. Critical casualties had lower mortality when blood was received (p < 0.01). Among critical casualties, blood transfusion was associated with survival irrespective of transport time within or greater than 60 minutes (p < 0.01).
Although data were limited, early blood transfusion was associated with battlefield survival in Iraq as it was in Afghanistan.
Performance improvement and epidemiological, level IV.
The overall approach to massive casualty triage has changed little in the past 200 years. As the military and civilian organizations prepare for the possibility of future large scale combat ...operations, terrorist attacks and natural disasters, potentially involving hundreds or even thousands of casualties, a modified approach is needed to conduct effective triage, initiate treatment and save as many lives as possible.
Military experience and review of analyses from the Department of Defense Trauma Registry are combined to introduce new concepts in triage and initial casualty management.
The classification of the scale of MASCAL, timeline of lifesaving interventions, immediate first pass actions prior to formal triage decisions during the first hour after injury, simplification of triage decisions, and the understanding that ultra-MASCAL will primarily require casualty movement and survival needs with few prehospital life-saving medical interventions are discussed.
Self-aid, bystander and first responder interventions are paramount and should be trained and planned extensively. Military and disaster planning should not only train these concepts, but should seek innovations to extend the timelines of effectiveness and to deliver novel capabilities within the timelines to the greatest extent possible.
Level III, Prognostic and Epidemiological.
Hemorrhage is the most common mechanism of death in battlefield casualties with potentially survivable injuries. There is evidence that early blood product transfusion saves lives among combat ...casualties. When compared to component therapy, fresh whole blood transfusion improves outcomes in military settings. Cold‐stored whole blood also improves outcomes in trauma patients. Whole blood has the advantage of providing red cells, plasma, and platelets together in a single unit, which simplifies and speeds the process of resuscitation, particularly in austere environments. The Joint Trauma System, the Defense Committee on Trauma, and the Armed Services Blood Program endorse the following: (1) whole blood should be used to treat hemorrhagic shock; (2) low‐titer group O whole blood is the resuscitation product of choice for the treatment of hemorrhagic shock for all casualties at all roles of care; (3) whole blood should be available within 30 min of casualty wounding, on all medical evacuation platforms, and at all resuscitation and surgical team locations; (4) when whole blood is not available, component therapy should be available within 30 min of casualty wounding; (5) all prehospital medical providers should be trained and logistically supported to screen donors, collect fresh whole blood from designated donors, transfuse blood products, recognize and treat transfusion reactions, and complete the minimum documentation requirements; (6) all deploying military personnel should undergo walking blood bank prescreen laboratory testing for transfusion transmitted disease immediately prior to deployment. Those who are blood group O should undergo anti‐A/anti‐B antibody titer testing.
PDF
