Disability-Adjusted Life Years Resulting from Ocular Injury among Deployed Service Members, 2001-2020.

PURPOSE: To quantify the burden of ocular injuries on deployed US service members by calculating disability-adjusted life years (DALYs). DESIGN: Retrospective, observational cohort study. PARTICIPANTS: US service members with ocular injuries sustained in combat zones from January 1, 2001 to May 19, 2020. METHODS: Health states and duration of injuries were identified using data from the Defense and Veterans Eye Injury and Vision Registry. These health states were mapped to disability weights from the Global Burden of Disease (GBD) study. Average duration of injury or illness was calculated until remission or death. For the latter, life expectancy at age of sustaining injury, as identified from US Life Tables from the National Vital Statistics Reports 2020, was used. Using Defense Manpower Data Center reports capturing number of service members deployed per year, incidence rates were calculated for ocular injury and DALYs. MAIN OUTCOME MEASURES: Disability-adjusted life years of ocular injury. RESULTS: Seventeen thousand five hundred fifty-five patients sustained ocular injury that incurred DALYs. In total, these injuries resulted in 11 214 DALYs (average, 0.64 DALYs per included patient and 20.6 DALYs per 10 000 US service members per year). Severe impairment of distance vision (77.9%) and blindness (10.6%) were the primary contributors of DALYs. Although only 9.3% of patients sustained a permanent ocular injury, permanent disability accounted for 99.5% of total DALYs. The average yearly incidence rate of ocular injury was 32.0 cases per 10 000 US service members. Foreign body was the most frequent injury type (2754 occurrences), followed by abrasion (2419 occurrences) and multiple injury types (1429 occurrences). The most DALYs occurred in patients with multiple injury types (2485 DALYs), followed by abrasion (accounting for 725 DALYs) and foreign body (accounting for 461 DALYs). DISCUSSION: We report higher average DALYs per case ratio among US service members compared with the general population studied by the GBD study, highlighting the differences in probabilities of permanent injury between the two studies. Our study provides understanding of the impact of ocular injuries on active-duty service members and lays the groundwork for further research and interventions to mitigate their burden. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Characterization of Humanitarian Trauma Care by US Military Facilities During Combat Operations in Afghanistan and Iraq.

OBJECTIVE: To characterize humanitarian trauma care delivered by US military treatment facilities (MTFs) in Afghanistan and Iraq during combat operations. BACKGROUND: International Humanitarian Law, which includes the Geneva Conventions, defines protections and standards of treatment to victims of armed conflicts. In 1949, these standards expanded to include injured civilians. In 2001, the Global War on Terror began in Afghanistan and expanded to Iraq in 2003. US MTFs provided care to all military forces, civilians, and enemy prisoners. A thorough understanding of the scope, epidemiology, resource requirements, and outcomes of civilian trauma in combat zones has not been previously characterized. METHODS: Retrospective cohort analysis of the Department of Defense Trauma Registry from 2005 to 2019. Inclusion criteria were civilians and Non-North Atlantic Treaty Organization (NATO) Coalition Personnel (NNCP) with traumatic injuries treated at MTFs in Afghanistan and Iraq. Patient demographics, mechanism of injury, resource requirements, procedures, and outcomes were categorized. RESULTS: A total of 29,963 casualties were eligible from the Registry. There were 16,749 (55.9%) civilians and 13,214 (44.1%) NNCP. The majority of patients were age above 13 years [26,853 (89.6%)] and male [28,000 (93.4%)]. Most injuries were battle-related: 12,740 (76.1%) civilians and 11,099 (84.0%) NNCP. Penetrating trauma was the most common cause of both battle and nonbattle injuries: 12,293 (73.4%) civilian and 10,029 (75.9%) NNCP. Median Injury Severity Score (ISS) was 9 in each cohort with ISS≥25 in 2236 (13.4%) civilians and 1398 (10.6%) NNCP. Blood products were transfused to 35% of each cohort: 5850 civilians received a transfusion with 2118 (12.6%) of them receiving ≥10 units; 4590 NNCPs received a transfusion with 1669 (12.6%) receiving ≥10 units. MTF mortality rates were civilians 1263 (7.5%) and NNCP 776 (5.9%). Interventions, both operative and nonoperative, were similar between both groups. CONCLUSIONS: In accordance with International Humanitarian Law, as well as the US military's medical rules of eligibility, civilians injured in combat zones were provided the same level of care as NNCP. Injured civilians and NNCP had similar mechanisms of injury, injury patterns, transfusion needs, and ISS. This analysis demonstrates resource equipoise in trauma care delivered to civilians and NNCP. Hospitals in combat zones must be prepared to manage large numbers of civilian casualties with significant human and material resources allocated to optimize survival. The provision of humanitarian trauma care is resource-intensive, and these data can be used to inform planning factors for current or future humanitarian care in combat zones.

Recovery of Hydroxytyrosol from Olive Mill Wastewater Using the Promiscuous Hydrolase/Acyltransferase PestE.

Olive mill wastewater (OMWW) is produced annually during olive oil extraction and contains most of the health-promoting 3-hydroxytyrosol of the olive fruit. To facilitate its recovery, enzymatic transesterification of hydroxytyrosol (HT) was directly performed in an aqueous system in the presence of ethyl acetate, yielding a 3-hydroxytyrosol acetate rich extract. For this, the promiscuous acyltransferase from Pyrobaculum calidifontis VA1 (PestE) was engineered by rational design. The best mutant for the acetylation of hydroxytyrosol (PestE_I208A_L209F_N288A) was immobilized on EziG2 beads, resulting in hydroxytyrosol conversions between 82 and 89 % in one hour, for at least ten reaction cycles in a buffered hydroxytyrosol solution. Due to inhibition by other phenols in OMWW the conversions of hydroxytyrosol from this source were between 51 and 62 %. In a preparative scale reaction, 13.8 mg (57 %) of 3-hydroxytyrosol acetate was extracted from 60 mL OMWW.

The risk of thromboembolic events with early intravenous 2- and 4-g bolus dosing of tranexamic acid compared to placebo in patients with severe traumatic bleeding: A secondary analysis of a randomized, double-blind, placebo-controlled, single-center trial.

BACKGROUND: Screening for the risk of thromboembolism (TE) due to tranexamic acid (TXA) in patients with severe traumatic injury has not been performed in randomized clinical trials. Our objective was to determine if TXA dose was independently-associated with thromboembolism. STUDY DESIGN AND METHODS: This is a secondary analysis of a single-center, double-blinded, randomized controlled trial comparing placebo to a 2-g or 4-g intravenous TXA bolus dose in trauma patients with severe injury. We used multivariable discrete-time Cox regression models to identify associations with risk for thromboembolic events within 30 days post-enrollment. Event curves were created using discrete-time Cox regression. RESULTS: There were 50 patients in the placebo group, 49 in the 2-g, and 50 in the 4-g TXA group. In adjusted analyses for thromboembolism, a 2-g dose of TXA had an hazard ratio (HR, 95% confidence interval [CI]) of 3.20 (1.12-9.11) (p = .029), and a 4-g dose of TXA had an HR (95% CI) of 5.33 (1.94-14.63) (p = .001). Event curves demonstrated a higher probability of thromboembolism for both doses of TXA compared to placebo. Other parameters independently associated with thromboembolism include time from injury to TXA administration, body mass index, and total blood products transfused. DISCUSSION: In patients with severe traumatic injury, there was a dose-dependent increase in the risk of at least one thromboembolic event with TXA. TXA should not be withheld, but thromboembolism screening should be considered for patients receiving a dose of at least 2-g TXA intravenously for traumatic hemorrhage.

Solvent screening, optimization and kinetic parameters of the biocatalytic epoxidation reaction of ß-pinene mediated by Novozym®435.

Monoterpenes, such as beta-pinene, are secondary metabolites widely used in the flavors and fragrance industries and can have their structure altered to enhance their applicability, such as producing epoxides, which are used as intermediaries for pharmaceuticals. Epoxides are commonly synthesized by the use of inorganic acids as catalysts, although the acid medium induces epoxide degradation. To overcome these limitations biocatalysis is shown as an alternative. Related to, this work aimed to perform the synthesis of ß-Pinene epoxide using Pseudozyma antarctica lipase B (Novozym®435) as a biocatalyst, while determining the independent variables that influence the reaction using experimental design tools. Different solvent systems were evaluated (cyclohexane, acetonitrile, ethyl acetate, and dichloromethane) until 72 h reaction time, from which ethyl acetate showed higher conversion into the epoxidized product (40% in 24 h). Under the other solvents systems, several oxidized by-products were obtained, such as ketones and aldehydes. Moreover, applying metrics of green chemistry, ethyl acetate was also corroborated as the most promising solvent, with a higher atom economy (66.8%) in comparison to the others (41.3%), and a smaller E-value (1.19). Ethyl acetate was the solvent/acyl donor of choice and had the molar ratio and percentage of biocatalyst increased, which resulted in 80% of the product after 3 h of reaction. To obtain an optimized model, four independent variables (temperature, stirring, molar ratio, percentage of biocatalyst) were evaluated using experimental design tools, Fractional Factorial Design and Central Composite Rotatable Design, with conversions ranging from 23 to 95% after 3 h. All the independent variables were statistically significant (p < 0.05) and had different degrees of impact on the conversion. Kinetic parameters of the reaction were determined using the Lineweaver-Burk model (results under 30.1 mmol for Km and 10.7 mmol.min-1 for Vmax). In conclusion, the combination of two different tools of experimental design provided the development of an optimized model for beta-Pinene epoxidation, achieving high conversion to the epoxidized product after 3 h.

Early Fasciotomy and Limb Salvage and Complications in Military Lower Extremity Vascular Injury.

BACKGROUND: Military guidelines endorse early fasciotomy after revascularization of lower extremity injuries to prevent compartment syndrome, but the real-world impact is unknown. We assessed the association between fasciotomy and amputation and limb complications among lower extremitys with vascular injury. METHODS: A retrospectively collected lower extremity injury database was queried for limbs undergoing attempted salvage with vascular procedure (2004-2012). Limbs were categorized as having undergone fasciotomy or not. Injury and treatment characteristics were collected, as were intervention timing data when available. The primary outcome measure was amputation. Multivariate models examined the impact of fasciotomy on limb outcomes. RESULTS: Inclusion criteria were met by 515 limbs, 335 (65%) with fasciotomy (median 7.7 h postinjury). Of 212 limbs, 174 (84%) with timing data had fasciotomy within 30 min of initial surgery. Compartment syndrome and suspicion of elevated pressure was documented in 127 limbs (25%; 122 had fasciotomy). Tourniquet and shunt use, fracture, multiple arterial and combined arteriovenous injuries, popliteal involvement, and graft reconstruction were more common in fasciotomy limbs. Isolated venous injury and vascular ligation were more common in nonfasciotomy limbs. Fasciotomy timing was not associated with amputation. Controlling for limb injury severity, fasciotomy was not associated with amputation but was associated with limb infection, motor dysfunction, and contracture. Sixty-three percent of fasciotomies were open for >7 d, and 43% had multiple closure procedures. Fasciotomy revision (17%) was not associated with increased amputation or complications. CONCLUSIONS: Fasciotomy after military lower extremity vascular injury is predominantly performed early, frequently without documented compartment pressure elevation. Early fasciotomy is generally performed in severely injured limbs with a subsequent high rate of limb complications.

Improved survival in critically injured combat casualties treated with fresh whole blood by forward surgical teams in Afghanistan.

BACKGROUND: The objective of this study was to assess transfusion strategies and outcomes, stratified by the combat mortality index, of casualties treated by small surgical teams in Afghanistan. Resuscitation that included warm fresh whole blood (FWB) was compared to blood component resuscitation. STUDY DESIGN AND METHODS: Casualties treated by a Role 2 surgical team in Afghanistan from 2008 to 2014 who received 1 or more units of red blood cells (RBCs) or FWB were included. Patients were excluded if they had incomplete data or length of stay less than 30 minutes. Patients were separated into two groups: 1) received FWB and 2) did not receive FWB; moreover, both groups potentially received plasma, RBCs, and platelets. The analysis was stratified by critically versus noncritically injured patients using the prehospital combat mortality index. Kaplan-Meier plot, log-rank test, and multivariable Cox regression were performed to compare survival. RESULTS: In FWB patients, median units of FWB and total blood product were 4.0 (interquartile range [IQR], 2.0-7.0) and 16.0 (IQR, 10.0-28.0), respectively. The Kaplan-Meier plot demonstrated that survival was similar between FWB (79.1%) and no-FWB (74.5%) groups (p = 0.46); after stratifying patients by the combat mortality index, the risk of mortality was increased in the no-FWB group (hazard ratio, 2.8; 95% confidence interval, 1.2-6.4) compared to the FWB cohort. CONCLUSION: In forward-deployed environments, where component products are limited, FWB has logistical advantages and was associated with reduced mortality in casualties with a critical combat mortality index. Additional analysis is needed to determine if these effects of FWB are appreciable in all trauma patients or just in those with severe physiologic derangement.

The use of low-titer group O whole blood is independently associated with improved survival compared to component therapy in adults with severe traumatic hemorrhage.

BACKGROUND: There is a resurgence in the use of low-titer group O whole blood (LTOWB) for hemorrhagic shock. We hypothesized the use of LTOWB compared to component therapy (CT) would be independently associated with improved 24-hour mortality. STUDY DESIGN AND METHODS: In this prospective observational study, trauma patients 18 years of age or older with massive transfusion protocol activations were included from August 17, 2018, to May 14, 2019. The primary outcome was 24-hour mortality. Secondary outcomes included 72-hour blood product totals, multiple organ dysfunction scores (MODS), and 28-day mortality. Multivariable logistic regression (MVLR) and Cox regression were performed to determine independent associations. RESULTS: There were no clinically meaningful differences in measures of injury severity between study groups (CT, n = 42; LTOWB, n = 44). There was no difference in MODS between study groups. The unadjusted mortality was not statistically different between the study groups (9/42 [21%] for CT vs. 7/44 [16%] for LTOWB; p = 0.518). In the MVLR model, LTOWB increased the odds of 24-hour survival by 23% (odds ratio 0.81, 95% confidence interval 0.69-0.96; p = 0.017). Adjusted survival curve analysis indicated improved survival at both 24 hours and 28 days for LTOWB patients (p < 0.001). Further stratification showed an association between LTOWB use and survival when maximum clot firmness (MCF) was 60 mm or less (p = 0.009). CONCLUSIONS: The use of LTOWB is independently associated with improved 24-hour and 28-day survival, and does not increase organ dysfunction at 72 hours. Use of LTOWB most impacted survival of patients with reduced clot firmness (MCF ≤60 mm). Collectively, these data support the clinical use and continued study of LTOWB for hemostatic resuscitation.

Association of organic solvents and occupational noise on hearing loss and tinnitus among adults in the U.S., 1999-2004.

PURPOSE: Exposure to organic solvents and noise may be causal agents in the development of hearing loss and tinnitus. The objectives of the present study were to examine the association of organic solvents with hearing loss and tinnitus and to assess the interaction of organic solvent and occupational noise exposure on hearing loss and tinnitus. METHODS: A secondary data analysis of data from the National Health and Nutrition Examination Survey and Occupational Information Network (O*NET) among a study population ranging from 1085 to 2471 study participants from 1999 to 2004. Multiple multivariate logistic regression models were used to assess the associations of individual organic solvent exposures as measured by blood biomarkers (1,4-dichlorobenzene, benzene, ethylbenzene, styrene, toluene, o-xylene, and m-/p-xylene) with self-reported hearing loss, audiometrically assessed hearing loss, and self-reported tinnitus. Models were adjusted for age, gender, race/ethnicity, diabetes, non-occupational noise exposure, smoking, and income. Organic solvents found to be statistically significantly associated with the outcome after adjusting for covariates were tested for interaction with occupational noise exposure. RESULTS: Solvent exposure was not statistically significantly associated with self-reported tinnitus. Benzene (OR 1.43, 95% CI 1.15-1.78), ethylbenzene (OR 1.24, 95% CI 1.02-1.50), and toluene (OR 1.27, 95% CI 1.06-1.52) concentrations were statistically significantly associated with increased adjusted odds of high-frequency hearing loss. No statistically significant interaction was observed between these solvents and occupational noise on high-frequency hearing loss. CONCLUSIONS: We found no evidence of an association between organic solvents and tinnitus; however, there was evidence of an association between organic solvent exposure and prevalence of high-frequency hearing loss.

Investigation of Pertussis Cases in a Texas County, 2008-2012.

OBJECTIVES: Within the past 25 years, there has been a dramatic increase in the incidence of pertussis cases in the United States. As such, this investigation reports on the high-risk groups and describes risk factors of pertussis cases in a large Texas county. METHODS: This study was a cross-sectional analysis of data collected by health department employees using the Texas Department of State Health Service's Pertussis Case Track Record, which is the standard investigation form for collecting vital information on pertussis cases. We extracted and analyzed county-level data for a 5-year period (2008-2012). The study population at risk included all current residents in this county, and cases included all who were clinically diagnosed as having confirmed or probable pertussis cases that were reported to the health department according to the Centers for Disease Control and Prevention case definition. The vaccination status of a case was defined as fully vaccinated, partially vaccinated, or not vaccinated. RESULTS: A total of 198 probable and confirmed pertussis cases were included in this analysis. Most of the cases were infants younger than 1 year old (n = 107). The largest category of cases was not vaccinated and of the rest, 32.8% were partially vaccinated, 17.2% had unknown vaccination status, and 13.1% were fully vaccinated. Only 48 (24.2%) sources of exposure were identified and they included fathers (14.6%), sisters (14.6%), brothers (14.6%), other children (14.6%), and mothers (12.5%). Many sources of exposure (n = 26, 54.1%) were unaware of their vaccination history. Hispanics accounted for 84.5% of cases in the younger than 1 year old group and 88.9% of cases were in the 1 to 2 years old group. With respect to race/ethnicity and vaccination status of the cases, 39.46% of Hispanics, 32% of whites, and 50% of blacks were reported to be unvaccinated. CONCLUSIONS: Increasing pertussis vaccination coverage among children, as well as providing booster shots to adults with special attention on the Hispanic population, may prove to be an effective strategy for health departments.

Developing and Implementing a Citywide Asthma Action Plan: A Community Collaborative Partnership.

OBJECTIVES: Asthma affects 1 in 10 children in the United States, with higher prevalence among children living in poverty. Organizations in San Antonio, Texas, partnered to design and implement a uniform, citywide asthma action plan to improve asthma management capacity in schools. METHODS: The asthma action plan template was modified from that of the Global Initiative for Asthma. School personnel were trained in symptom recognition, actions to take, and use of equipment before the asthma action plan implementation. The annual Asthma Action Plan Summit was organized as a forum for school nurses, healthcare providers, and members of the community to exchange ideas and strategies on implementation, as well as to revise the plan. RESULTS: The asthma action plan was implemented in all 16 local school districts. Feedback received from school nurses suggests that the citywide asthma action plan resulted in improved asthma management and student health at schools. CONCLUSIONS: The evidence in this study suggests that community organizations can successfully collaborate to implement a citywide health initiative similar to the asthma action plan.

A trauma expert consensus: Capabilities are required early to improve survivability from traumatic injury.

BACKGROUND: Mortality reviews examine US military fatalities resulting from traumatic injuries during combat operations. These reviews are essential to the evolution of the military trauma system to improve individual, unit, and system-level trauma care delivery and inform trauma system protocols and guidelines. This study identifies specific prehospital and hospital interventions with the potential to provide survival benefits. METHODS: US Special Operations Command fatalities with battle injuries deemed potentially survivable (2001-2021) were extracted from previous mortality reviews. A military trauma review panel consisting of trauma surgeons, forensic pathologists, and prehospital and emergency medicine specialists conducted a methodical review to identify prehospital, hospital, and resuscitation interventions (e.g., laparotomy, blood transfusion) with the potential to have provided a survival benefit. RESULTS: Of 388 US Special Operations Command battle-injured fatalities, 100 were deemed potentially survivable. Of these (median age, 29 years; all male), 76.0% were injured in Afghanistan, and 75% died prehospital. Gunshot wounds were in 62.0%, followed by blast injury (37%), and blunt force injury (1.0%). Most had a Maximum Abbreviated Injury Scale severity classified as 4 (severe) (55.0%) and 5 (critical) (41.0%). The panel recommended 433 interventions (prehospital, 188; hospital, 315). The most recommended prehospital intervention was blood transfusion (95%), followed by finger/tube thoracostomy (47%). The most common hospital recommendations were thoracotomy and definitive vascular repair. Whole blood transfusion was assessed for each fatality: 74% would have required ≥10 U of blood, 20% would have required 5 to 10 U, 1% would have required 1 to 4 U, and 5% would not have required blood products to impact survival. Five may have benefited from a prehospital laparotomy. CONCLUSION: This study systematically identified capabilities needed to provide a survival benefit and examined interventions needed to inform trauma system efforts along the continuum of care. The determination was that blood transfusion and massive transfusion shortly after traumatic injury would impact survival the most. LEVEL OF EVIDENCE: Prognostic and Epidemiological; Level V.

The thin red line: Blood planning factors and the enduring need for a robust military blood system to support combat operations.

ABSTRACT: Battlefield lessons learned are forgotten; the current name for this is the Walker Dip. Blood transfusion and the need for a Department of Defense Blood Program are lessons that have cycled through being learned during wartime, forgotten, and then relearned during the next war. The military will always need a blood program to support combat and contingency operations. Also, blood supply to the battlefield has planning factors that have been consistent over a century. In 2024, it is imperative that we codify these lessons learned. The linchpins of modern combat casualty care are optimal prehospital care, early whole blood transfusion, and forward surgical care. This current opinion comprised of authors from all three military Services, the Joint Trauma System, the Armed Services Blood Program, blood SMEs and the CCC Research Program discuss two vital necessities for a successful military trauma system: (1) the need for an Armed Services Blood Program and (2) Planning factors for current and future deployed military ere is no effective care for wounded soldiers, and by extension there is no effective military medicine.

Patterns of Palliation: A Review of Casualties That Received Pain Management Before Reaching Role 2 in Afghanistan.

INTRODUCTION: Battlefield pain management changed markedly during the first 20 years of the Global War on Terror. Morphine, long the mainstay of combat analgesia, diminished in favor of fentanyl and ketamine for military pain control, but the options are not hemodynamically or psychologically equivalent. Understanding patterns of prehospital analgesia may reveal further opportunities for combat casualty care improvement. MATERIALS AND METHODS: Using Department of Defense Trauma Registry data for the Afghanistan conflict from 2005 to 2018, we examined 2,402 records of prehospital analgesia administration to assess temporal trends in medication choice and proportions receiving analgesia, including subanalysis of a cohort screened for an indication with minimal contraindication for analgesia. We further employed frequency matching to explore the presence of disparities in analgesia by casualty affiliation. RESULTS: Proportions of documented analgesia increased throughout the study period, from 0% in 2005 to 70.6% in 2018. Afghan casualties had the highest proportion of documented analgesia (53.0%), versus U.S. military (31.9%), civilian/other (23.3%), and non-U.S. military (19.3%). Fentanyl surpassed morphine in the frequency of administration in 2012. The median age of those receiving ketamine was higher (30 years) than those receiving fentanyl (26 years) or nonsteroidal anti-inflammatory drugs (23 years). Among the frequency-matched subanalysis, the odds ratio for ketamine administration with Afghan casualties was 1.84 (95% CI, 1.30-2.61). CONCLUSIONS: We observed heterogeneity of prehospital patient care across patient affiliation groups, suggesting possible opportunities for improvement toward an overall best practice system. General increase in documented prehospital pain management likely reflects efforts toward complete documentation, as well as improved options for analgesia. Current combat casualty care documentation does not include any standardized pain scale.

A Deeper Dive Into Combat Medic Training.

The recent article by Knisely et al. provides a comprehensive review and summary of recent literature describing simulation techniques, training strategies, and technologies to teach medics combat casualty care skills. Some of the results reported by Knisely et al. align with the findings of our team's work, and these findings may be helpful to military leadership with their ongoing efforts to maintain medical readiness. Accordingly, we provide some additional contextual understanding to the results of Knisely et al. in this commentary. Our team recently published two papers describing the results of a large survey that examined Army medic pre-deployment training. Combining the findings of Knisely et al. along with some of the contextual information from our work, we provide some recommendations for improving and optimizing the pre-deployment training paradigm for medics.

Finding the bleeding edge: 24-hour mortality by unit of blood product transfused in combat casualties from 2002-2020.

BACKGROUND: Transfusion studies in civilian trauma patients have tried to identify a general futility threshold. We hypothesized that in combat settings there is no general threshold where blood product transfusion becomes unbeneficial to survival in hemorrhaging patients. We sought to assess the relationship between the number of units of blood products transfused and 24-hour mortality in combat casualties. METHODS: A retrospective analysis of the Department of Defense Trauma Registry supplemented with data from the Armed Forces Medical Examiner. Combat casualties who received at least one unit of blood product at US military medical treatment facilities (MTFs) in combat settings (2002-2020) were included. The main intervention was the total units of any blood product transfused, which was measured from the point of injury until 24 hours after admission from the first deployed MTF. The primary outcome was discharge status (alive, dead) at 24 hours from time of injury. RESULTS: Of 11,746 patients included, the median age was 24 years, and most patients were male (94.2%) with penetrating injury (84.7%). The median injury severity score was 17 and 783 (6.7%) patients died by 24 hours. Median units of blood products transfused was 8. Most blood products transfused were red blood cells (50.2%), followed by plasma (41.1%), platelets (5.5%), and whole blood (3.2%). Among the 10 patients who received the most units of blood product (164 units to 290 units), 7 survived to 24 hours. The maximum amount of total blood products transfused to a patient who survived was 276 units. Of the 58 patients who received over 100 units of blood product, 20.7% died by 24 hours. CONCLUSION: While civilian trauma studies suggest the possibility of futility with ultra-massive transfusion, we report that the majority (79.3%) of combat casualties who received transfusions greater than 100 units survived to 24 hours. These results do not support a threshold for futility of blood product transfusion. Further analysis as to predictors for mortality will help in situations of blood product and resource constraints. LEVEL OF EVIDENCE: Prognostic and Epidemiological; Level IV.

Prior Extracorporeal Membrane Oxygenation (ECMO) Experience and Performance in High-Fidelity Simulation Scenarios.

Background Extracorporeal Membrane Oxygenation (ECMO) provides a heart-lung bypass for patients with life-threatening cardiorespiratory failure. It is a classic low-volume, a high-risk procedure that requires specialized training to develop and maintain competence. Therefore, our ability to train efficiently and effectively is essential. The purpose of this study is to determine if specific participant training or experience leads to better performance in emergency ECMO scenarios during high-fidelity simulation training. Methods Fifty-one physicians, nurses, and respiratory/medical technicians participated in a study comparing an animal model vs. simulation-based ECMO education. All completed a multiple-choice questionnaire about prior ECMO experience and other demographics, as well as a four-hour pre-lab didactic session. They completed individual ECMO scenarios with both modalities during two sessions, and task completion times (minutes) and scores (percentage) were measured using a validated ECMO skills assessment tool. The scores of the 19 participants who completed the simulation-based scenarios during their first session were further analyzed in the context of their self-reported ECMO experience, and participants were divided into a novice group and an experienced group. Statistical testing included the Mann-Whitney U test (times) and Fisher's exact test (scores). Results Data from the 19 participants who completed the simulation-based ECMO training on the first session showed no statistically significant differences in the task completion time or scores among those in the novice group vs. the experienced group in the years of ECMO experience category (28 vs. 34 minutes; p=0.66 and 61% vs. 62%; p=0.54), a number of cannulations category (30 vs. 25 minutes; p=0.11 and 59% vs. 62%; p=0.82) or the number of ECMO patients cared for category (28 vs. 34 minutes; p=0.30 and 57% vs. 62%; p=0.54). Findings were similar for both the lecture-based training and simulation-based training categories, respectively (33 vs. 28 minutes; p=0.71 and 62% vs. 60%; p=0.91 and 34 vs. 28 minutes; p=0.74 and 63% vs. 58%; p=0.12). Conclusion Among this small subset of participants, we observed no statistically significant differences in performance based on participant experience during simulation-based ECMO scenarios. The didactic/review sessions preceding the training may have contributed to an effective form of training for participants with no prior ECMO experience. Due to the small sample size of this study, further studies are needed to better elucidate what factors lead to better performance in emergency ECMO scenarios.

Determining resuscitation outcomes in combat casualties: Design of the Deployed Hemostatic Emergency Resuscitation of Traumatic Exsanguinating Shock (Deployed HEROES) study.

BACKGROUND: During the course of the recent conflicts, the recommendations for resuscitation practices have evolved, but there has been no comprehensive comparative effectiveness study of these resuscitation strategies. The objective of this study was to describe the development and study design of the Deployed Hemostatic Emergency Resuscitation of Traumatic Exsanguinating Shock (Deployed HEROES) study-the first comprehensive analysis of military resuscitation practices in the deployed environment from October 2001 to October 2019. METHODS: This retrospective cohort study uses the Department of Defense Trauma Registry, Armed Services Blood Program database, and Military Trauma Mortality Review, while abstractors will use Theater Medical Data Store and Web Interface Patient Records to collect transfusion timing data. This study includes patients, who received blood products or died before receiving blood, treated at US military medical treatment facilities. The primary endpoints are survival at 6 hours, 24 hours, and 30 days postinjury. Secondary outcomes include infection, renal dysfunction, pulmonary dysfunction, and thromboembolic event. Exposure will be defined by blood product transfusion. Study groups will be frequency matched. Cox proportional hazards will compare patients who received warm fresh whole blood, low titer type-O whole blood, or only component therapy, while using adjustment for type of blood product transfused as a time-dependent covariate. Multilevel mixed-effects logistic regression will determine the effect of incompatible plasma in low titer type-O whole blood. RESULTS: An analysis plan for the Deployed HEROES study was developed with the aim of minimizing bias. CONCLUSION: This study will inform the optimal resuscitation strategies, which will potentially have a substantial impact on combat mortality. If whole blood is found to be the optimal transfusion strategy, this finding will be crucial in future operating environments involving dispersed medical assets. These results will provide critical information necessary for combat casualty care guidelines. LEVEL OF EVIDENCE: Prognostic and epidemiological; Level III.

A Retrospective Cohort Study of Burn Casualties Transported by the US Army Burn Flight Team and US Air Force Critical Care Air Transport Teams.

INTRODUCTION: The US Army Burn Center, the only burn center in the Department of Defense provides comprehensive burn care. The Burn Flight Team (BFT) provides specialized burn care during transcontinental evacuation. During Operations Iraqi and Enduring Freedom, burn injuries accounted for approximately 5% of all injuries in military personnel. To augment BFT capacity, US Air Force Critical Care Air Transport Teams (CCATTs) mobilized to transport burn patients. The purpose of this study was to describe critically ill, burn injured patients transported to the US Army Burn Center by BFT or CCATT, to compare and contrast characteristics, evacuation procedures, in-flight treatments, patient injuries/illnesses, and outcomes between the two groups. MATERIALS AND METHODS: We conducted a retrospective cohort study of CCATT and BFT patients, admitted to the burn ICU between January 1, 2001 and September 30, 2018. Patients with total body surface area burned (TBSA) >30% were evacuated by BFT, while CCATT evacuated patients with ≤ 30% TBSA. RESULTS: Ninety-seven patients met inclusion criteria for this study. Of these, 40 (41%) were transported by the BFT and 57 (59%) were transported by CCATTs. Compared with patients transported by CCATTs, patients transferred by the BFT had higher median TBSA and full-thickness burn size, higher prevalence of chest, back and groin burns, and higher prevalence of inhalation injury. BFT patients had increased hospital days (62 vs. 37; P = .08), ICU days (29 vs. 12; P = .003) and ventilator days (14 vs. 6; P < .001). TBSA was the only variable significantly associated with ARDS (aOR = 1.04; 95% CI: 1.01, 1.08; P = 0.04), renal failure (aOR = 1.07; 95% CI: 1.03, 1.11; P = .002), and mortality (aOR = 1.08; 95% CI: 1.03, 1.13; P = .001). CONCLUSIONS: Evacuation by the BFT was associated with increased ICU and ventilator days, increased mortality, and a greater risk for developing renal failure. The severity of injury/TBSA likely accounted for most of these differences.

Whole blood at the tip of the spear: A retrospective cohort analysis of warm fresh whole blood resuscitation versus component therapy in severely injured combat casualties.

BACKGROUND: Death from uncontrolled hemorrhage occurs rapidly, particularly among combat casualties. The US military has used warm fresh whole blood during combat operations owing to clinical and operational exigencies, but published outcomes data are limited. We compared early mortality between casualties who received warm fresh whole blood versus no warm fresh whole blood. METHODS: Casualties injured in Afghanistan from 2008 to 2014 who received ≥2 red blood cell containing units were reviewed using records from the Joint Trauma System Role 2 Database. The primary outcome was 6-hour mortality. Patients who received red blood cells solely from component therapy were categorized as the non-warm fresh whole blood group. Non- warm fresh whole blood patients were frequency-matched to warm fresh whole blood patients on identical strata by injury type, patient affiliation, tourniquet use, prehospital transfusion, and average hourly unit red blood cell transfusion rates, creating clinically unique strata. Multilevel mixed effects logistic regression adjusted for the matching, immortal time bias, and other covariates. RESULTS: The 1,105 study patients (221 warm fresh whole blood, 884 non-warm fresh whole blood) were classified into 29 unique clinical strata. The adjusted odds ratio of 6-hour mortality was 0.27 (95% confidence interval 0.13-0.58) for the warm fresh whole blood versus non-warm fresh whole blood group. The reduction in mortality increased in magnitude (odds ratio = 0.15, P = .024) among the subgroup of 422 patients with complete data allowing adjustment for seven additional covariates. There was a dose-dependent effect of warm fresh whole blood, with patients receiving higher warm fresh whole blood dose (>33% of red blood cell-containing units) having significantly lower mortality versus the non-warm fresh whole blood group. CONCLUSION: Warm fresh whole blood resuscitation was associated with a significant reduction in 6-hour mortality versus non-warm fresh whole blood in combat casualties, with a dose-dependent effect. These findings support warm fresh whole blood use for hemorrhage control as well as expanded study in military and civilian trauma settings.