Russ S. Kotwal

Eliminating Preventable Death on the Battlefield

OBJECTIVE To evaluate battlefield survival in a novel command-directed casualty response system that comprehensively integrates Tactical Combat Casualty Care guidelines and a prehospital trauma registry. DESIGN Analysis of battle injury data collected during combat deployments. SETTING Afghanistan and Iraq from October 1, 2001, through March 31, 2010. PATIENTS Casualties from the 75th Ranger Regiment, US Army Special Operations Command. MAIN OUTCOME MEASURES Casualties were scrutinized for preventable adverse outcomes and opportunities to improve care. Comparisons were made with Department of Defense casualty data for the military as a whole. RESULTS A total of 419 battle injury casualties were incurred during 7 years of continuous combat in Iraq and 8.5 years in Afghanistan. Despite higher casualty severity indicated by return-to-duty rates, the regiments rates of 10.7% killed in action and 1.7% who died of wounds were lower than the Department of Defense rates of 16.4% and 5.8%, respectively, for the larger US military population (P = .04 and P = .02, respectively). Of 32 fatalities incurred by the regiment, none died of wounds from infection, none were potentially survivable through additional prehospital medical intervention, and 1 was potentially survivable in the hospital setting. Substantial prehospital care was provided by nonmedical personnel. CONCLUSIONS A command-directed casualty response system that trains all personnel in Tactical Combat Casualty Care and receives continuous feedback from prehospital trauma registry data facilitated Tactical Combat Casualty Care performance improvements centered on clinical outcomes that resulted in unprecedented reduction of killed-in-action deaths, casualties who died of wounds, and preventable combat death. This data-driven approach is the model for improving prehospital trauma care and casualty outcomes on the battlefield and has considerable implications for civilian trauma systems.

The Effect of a Golden Hour Policy on the Morbidity and Mortality of Combat Casualties

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.

Safety and efficacy of oral transmucosal fentanyl citrate for prehospital pain control on the battlefield.

BACKGROUND Acute pain, resulting from trauma and other causes, is a common condition that imposes a need for prehospital analgesia on and off the battlefield. The narcotic most frequently used for prehospital analgesia on the battlefield during the past century has been morphine. Intramuscular morphine has a delayed onset of pain relief that is suboptimal and difficult to titrate. Although intravenously administered morphine can readily provide rapid and effective prehospital analgesia, oral transmucosal fentanyl citrate (OTFC) is a safe alternative that does not require intravenous access. This study evaluates the safety and efficacy of OTFC in the prehospital battlefield environment. METHODS Data collected during combat deployments (Afghanistan and Iraq) from March 15, 2003, to March 31, 2010, were analyzed. Patients were US Army Special Operations Command casualties. Patients receiving OTFC for acute pain were evaluated. Pretreatment and posttreatment pain intensities were quantified by the verbal numeric rating scale (NRS) from 0 to 10. OTFC adverse effects and injuries treated were also evaluated. RESULTS A total of 286 patients were administered OTFC, of whom 197 had NRS pain evaluations conducted before and approximately 15 minutes to 30 minutes following treatment. The difference between NRS pain scores at 0 minutes (NRS, 8.0 [1.4]) and 15 minutes to 30 minutes (NRS, 3.2 [2.1]) was significant (p < 0.001). Only 18.3% (36 of 197) of patients were also administered other types of analgesics. Nausea was the most common adverse effect as reported by 12.7% (25 of 197) of patients. The only major adverse effect occurred in the patient who received the largest opioid dose, 3,200-µg OTFC and 20-mg morphine. This patient exhibited hypoventilation and saturation of less than 90% requiring low-dose naloxone. CONCLUSION OTFC is a rapid and noninvasive pain management strategy that provides safe and effective analgesia in the prehospital battlefield setting. OTFC has considerable implications for use in civilian prehospital and austere environments. LEVEL OF EVIDENCE Therapeutic study, level IV.

Efficacy of point-of-injury combat antimicrobials.

BACKGROUND Infection is a major complication associated with combat-related injuries. One strategy to decrease infections is immediate delivery of antimicrobials at or near the point-of-injury by the casualty or the first medical responder. The 75th Ranger Regiment systematically collects data on prehospital battlefield care, including antimicrobial administration. We review infectious complications and colonization rates associated with delivery of point-of-injury antimicrobial therapy. METHODS We retrospectively reviewed casualty treatment data from the 75th Ranger Regiment prehospital trauma registry on patients injured between March 2003 and March 2010 and linked this to electronic medical record data to look for the presence of bacterial infection or colonization within 30 days of injury. Patient demographics, antimicrobial therapy, and outcomes were evaluated. Assessment of colonization included surveillance screening cultures performed for multidrug-resistant bacteria, including Acinetobacter baumannii and methicillin-resistant Staphylococcus aureus, at US military hospitals in the combat zone, Germany, and stateside. RESULTS Of 405 total casualties, 28 (6.9%) were infected with gram-negative bacteria, primarily A. baumannii. Of those who were not returned to duty or died near the time of injury, 28 of 211 (13.3%) were infected. The only identified risk factor for infection was higher military Injury Severity Score. Prehospital administration of antimicrobials to 113 of 405 casualties (27.9%), including 8 of the 28 infected casualties, did not affect infection or colonization rates. CONCLUSIONS Although limited by population size, a significant difference in infection rates and multidrug-resistant pathogen colonization was not seen in those casualties who received single-dose broad-spectrum antimicrobials at the point-of-injury, confirming neither benefit nor harm. Overall adherence with initiating point-of-injury antimicrobials was low.

Performance of Junctional Tourniquets in Normal Human Volunteers

Abstract Background. Inguinal bleeding is a common and preventable cause of death on the battlefield. Four FDA-cleared junctional tourniquets (Combat Ready Clamp [CRoC], Abdominal Aortic and Junctional Tourniquet [AAJT], Junctional Emergency Treatment Tool [JETT], and SAM Junctional Tourniquet [SJT]) were assessed in a laboratory on volunteers in order to describe differential performance of models. Objective. To examine safety and effectiveness of junctional tourniquets in order to inform the discussions of device selection for possible fielding to military units. Methods. The experiment measured safety and effectiveness parameters over timed, repeated applications. Lower extremity pulses were measured in 10 volunteers before and after junctional tourniquet application aimed at stopping the distal pulse assessed by Doppler auscultation. Safety was determined as the absence of adverse events during the time of application. Results. The CRoC, SJT, and JETT were most effective; their effectiveness did not differ (p > 0.05). All tourniquets were applied safely and successfully in at least one instance each, but pain varied by model. Subjects assessed the CRoC as most tolerable. The CRoC and SJT were the fastest to apply. Users ranked CRoC and SJT equally as performing best. Conclusion. The CRoC and SJT were the best-performing junctional tourniquets using this model.

Association of Prehospital Blood Product Transfusion During Medical Evacuation of Combat Casualties in Afghanistan With Acute and 30-Day Survival

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.

Prehospital Pain Medication Use by U.S. Forces in Afghanistan

We report the results of a process improvement initiative to examine the current use and safety of prehospital pain medications by U.S. Forces in Afghanistan. Prehospital pain medication data were prospectively collected on 309 casualties evacuated from point of injury (POI) to surgical hospitals from October 2012 to March 2013. Vital signs obtained from POI and flight medics and on arrival to surgical hospitals were compared using one-way analysis of variance test. 119 casualties (39%) received pain medication during POI care and 283 (92%) received pain medication during tactical evacuation (TACEVAC). Morphine and oral transmucosal fentanyl citrate were the most commonly used pain medications during POI care, whereas ketamine and fentanyl predominated during TACEVAC. Ketamine was associated with increase in systolic blood pressure compared to morphine (+7 ± 17 versus -3 ± 14 mm Hg, p = 0.04). There was no difference in vital signs on arrival to the hospital between casualties who received no pain medication, morphine, fentanyl, or ketamine during TACEVAC. In this convenience sample, fentanyl and ketamine were as safe as morphine for prehospital use within the dose ranges administered. Future efforts to improve battlefield pain control should focus on improved delivery of pain control at POI and the role of combination therapies.

Analysis of Prehospital Documentation of Injury-Related Pain Assessment and Analgesic Administration on the Contemporary Battlefield

Abstract In addition to life-saving interventions, the assessment of pain and subsequent administration of analgesia are primary benchmarks for quality emergency medical services care which should be documented and analyzed. Analyze US combat casualty data from the Department of Defense Trauma Registry (DoDTR) with a primary focus on prehospital pain assessment, analgesic administration and documentation. Retrospective cohort study of battlefield prehospital and hospital casualty data were abstracted by DoDTR from available records from 1 September 2007 through 30 June 2011. Data included demographics; injury mechanism; prehospital and initial combat hospital pain assessment documented by standard 0-to-10 numeric rating scale; analgesics administered; and survival outcome. Records were available for 8,913 casualties (median ISS of 5 [IQR 2 to 10]; 98.7% survived). Prehospital analgesic administration was documented for 1,313 cases (15%). Prehospital pain assessment was recorded for 581 cases (7%; median pain score 6 [IQR 3 to 8]), hospital pain assessment was recorded for 5,007 cases (56%; median pain score5 [CI95% 3 to 8]), and 409 cases (5%) had both prehospital and hospital pain assessments that could be paired. In this paired group, 49.1% (201/409) had alleviation of pain evidenced by a decrease in pain score (median 4,, IQR 2 to 5); 23.5% (96/409) had worsening of pain evidenced by an increase in pain score (median 3, CI95 2.8 to 3.7, IQR 1 to 5); 27.4% (112/409) had no change; and the overall difference was an average decrease in pain score of 1.1 (median 0, IQR 0 to 3, p < 0.01). Time-series analysis showed modest increases in prehospital and hospital pain assessment documentation and prehospital analgesic documentation. Our study demonstrates that prehospital pain assessment, management, and documentation remain primary targets for performance improvement on the battlefield. Results of paired prehospital to hospital pain scores and time-series analysis demonstrate both feasibility and benefit of prehospital analgesics. Future efforts must also include an expansion of the prehospital battlefield analgesic formulary.

Laboratory Assessment of Out-of-hospital Interventions to Control Junctional Bleeding from the Groin in a Manikin Model

Abstract : Junctional body regions between the trunk and its appendages, such as the groin, are too proximal for a regular limb tourniquet to fit [1,2]. Not since 1993 s Black Hawk Down has junctional hemorrhage control become such a hot topic in military casualty care [1 7]. In February 2013, the US military s Task Force Medical Afghanistan requested a fill of a gap in junctional hemorrhage control as an urgent operational need, meaning that junctional hemorrhage control devices should be considered urgently to fill a gap in medical care in war. A small but growing body of evidence indicates that hemorrhage control can be attained out-of-hospital with mechanical compression, using such interventions as medical devices, on a pressure point proximal to a bleeding wound [3 9]. To evaluate laboratory use of junctional hemorrhage control interventions, wegathered data on stopping groin bleeding in a manikin model to understand the plausibility of such interventions for future human subject research. Under an approved protocol, we tested efficacy of interventions in a manikin designed to trainmedics in out-of-hospital hemorrhage control (Combat Ready Clamp [CRoC] Trainer Manikin, Operative Experience, Inc, North East,MD).We filled the blood reservoirwith 4 liters ofwater; we refilled the reservoir after 5 iterations or 1.5 liters of lost fluid, whichever came first. The manikin had a right-groin gunshot wound through the proximal thighwhere the common femoral artery flow was controllable by skin compression over it at the level of the inguinal fold. There was 3 cm between the pressure point where compression was applied and the proximal extent of the wound. Interventions were timed, blood loss was measured, and efficacy was noted. Efficacy was operationally defined as visually stopped flow into the wound fromthe vessel lumen.

Reexamination of a Battlefield Trauma Golden Hour Policy

BACKGROUND 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. METHODS 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. RESULTS 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). CONCLUSION Reduction in KIA mortality is associated with early treatment capabilities, blunt mechanism, select body locations of injury, and rapid transport. LEVEL OF EVIDENCE Therapy, level III.BACKGROUND 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. METHODS 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. RESULTS 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). CONCLUSION Reduction in KIA mortality is associated with early treatment capabilities, blunt mechanism, select body locations of injury, and rapid transport. LEVEL OF EVIDENCE Therapy, level III.