Blood consumption in the Role 2 setting: A Department of Defense Trauma Registry analysis.

BACKGROUND: The Role 2 setting represents the most far-forward military treatment facility with limited surgical and holding capabilities. There are limited data to guide recommendations on blood product utilization at the Role 2. We describe the consumption of blood products in this setting. STUDY DESIGN AND METHODS: We analyzed data from 2007 to 2023 from the Department of Defense Trauma Registry (DODTR) that received care at a Role 2. We used descriptive and inferential statistics to characterize the volumes of blood products consumed in this setting. We also performed a secondary analysis of US military, Coalition, and US contractor personnel. RESULTS: Within our initial cohort analysis of 15,581 encounters, 17% (2636) received at least one unit of PRBCs or whole blood, of which 11% received a submassive transfusion, 4% received a massive transfusion, and 1% received a supermassive transfusion. There were 6402 encounters that met inclusion for our secondary analysis. With this group, 5% received a submassive transfusion, 2% received a massive transfusion, and 1% received a supermassive transfusion. CONCLUSIONS: We described volumes of blood products consumed at the Role 2 during recent conflicts. The maximum number of units consumed among survivors exceeds currently recommended available blood supply. Our findings suggest that rapid resupply and cold-stored chain demands may be higher than anticipated in future conflicts.

A survey of low titer O whole blood use within the trauma quality improvement program registry.

INTRODUCTION: The use of low titer O whole blood (LTOWB) has expanded although it remains unclear how many civilian trauma centers are using LTOWB. METHODS: We analyzed data on civilian LTOWB recipients in the American College of Surgeons Trauma Quality Improvement Program (TQIP) database 2020-2021. Unique facility keys were used to determine the number of centers that used LTOWB in that period. RESULTS: A total of 16,603 patients received LTOWB in the TQIP database between 2020 and 2021; 6600 in 2020, and 10,003 in 2021. The total number of facilities that reported LTOWB use went from 287/779 (37%) in 2020 to 302/795 (38%) in 2021. Between 2020 and 2021, among all level 1-3 designated trauma facilities that report to TQIP LTOWB use increased at level-1 centers (118 to 129), and level-2 centers (81 to 86), but decreased in level-3 facilities (9 to 4). Among pediatric and dual pediatric-adult designated hospitals there was a decrease in the number of pediatric level-1 centers (29 to 28) capable of administering LTOWB. Among centers with either single or dual level-1 trauma center designation with adult centers, the number that administered LTOWB to injured pediatric patients also decreased from 17 to 10, respectively. CONCLUSIONS: There was an increase in the number of facilities transfusing LTOWB between 2020 and 2021. The use of LTOWB is underutilized in children at centers that have it available. These findings inform the expansion of LTOWB use in trauma.

The employment of resuscitative endovascular balloon occlusion of the aorta in deployed settings.

BACKGROUND: Resuscitative endovascular balloon occlusion of the aorta (REBOA) has been often used in place of open aortic occlusion for management of hemorrhagic shock in trauma. There is a paucity of data evaluating REBOA usage in military settings. STUDY DESIGN AND METHODS: We queried the Department of Defense Trauma Registry (DODTR) for all cases with at least one intervention or assessment available within the first 72 h after injury between 2007 and 2023. We used relevant procedural codes to identify the use of REBOA within the DODTR, and we used descriptive statistics to characterize its use. RESULTS: We identified 17 cases of REBOA placed in combat settings from 2017 to 2019. The majority of these were placed in the operating room (76%) and in civilian patients (70%). A penetrating mechanism caused the injury in 94% of cases with predominantly the abdomen and extremities having serious injuries. All patients subsequently underwent an exploratory laparotomy after REBOA placement, with moderate numbers of patients having spleen, liver, and small bowel injuries. The majority (82%) of included patients survived to hospital discharge. DISCUSSION: We describe 17 cases of REBOA within the DODTR from 2007 to 2023, adding to the limited documentation of patients undergoing REBOA in military settings. We identified patterns of injury in line with previous studies of patients undergoing REBOA in military settings. In this small sample of military casualties, we observed a high survival rate.

Interventions associated with survival after prehospital intubation in the deployed combat setting.

INTRODUCTION: Airway compromise is the second leading cause of potentially preventable death on the battlefield. Prehospital airway management is often unavoidable in a kinetic combat environment and expected to increase in future wars where timely evacuation will be unreliable and air superiority not guaranteed. We compared characteristics of survivors to non-survivors among combat casualties undergoing prehospital airway intubation. MATERIALS AND METHODS: We requested all Department of Defense Trauma Registry (DODTR) encounters during 2007-2023 with documentation of any airway intervention or assessment within the first 72-h after injury. We conducted a retrospective cohort study of all casualties with intubation documented in the prehospital setting. We used descriptive and inferential statistical analysis to compare survivors through 7 days post injury versus non-survivors. We constructed 3 multivariable logistic regression models to test for associations between interventions and 7-day survival after adjusting for injury severity score, mechanism of injury, and receipt of sedatives, paralytics, and blood products. RESULTS: There were 1377 of 48,301 patients with documentation of prehospital intubation in a combat setting. Of these, 1028 (75%) survived through 7 days post injury. Higher proportions of survivors received ketamine, paralytic agents, parenteral opioids, and parenteral benzodiazepines; there was no difference in the proportions of survivors versus non-survivors receiving etomidate. The multivariable models consistently demonstrated positive associations between 7-day survival and receipt of non-depolarizing paralytics and opioid analgesics. CONCLUSIONS: We found an association between non-depolarizing paralytic and opioid receipt with 7-day survival among patients undergoing prehospital intubation. The literature would benefit from future multi-center randomized controlled trials to establish optimal pharmacologic strategies for trauma patients undergoing prehospital intubation.

Implementing Tourniquet Conversion Guidelines for Civilian EMS and Prehospital Organizations : A Case Report and Review.

Since the first documented use of a tourniquet in 1674, the popularity of tourniquets has waxed and waned. During recent wars and more recently in Emergency Medical Services systems, the tourniquet has been proven to be a valuable tool in the treatment of life-threatening hemorrhage. However, tourniquet use is not without risk, and several studies have demonstrated adverse events and morbidity associated with tourniquet use in the prehospital setting, particularly when left in place for more than 2 h. Consequently, the US military's Committee on Tactical Combat Casualty Care has recommended guidelines for prehospital tourniquet conversion to reduce the risk of adverse events associated with tourniquets once the initial hemorrhage has been controlled. Emergency Medical Services systems that operate in rural, frontier, and austere environments, especially those with transport times to definitive care that routinely exceed 2 h, may consider implementing similar tourniquet conversion guidelines.

A Contemporary Analysis of Combat-related Urological Injuries: Data From the Department of Defense Trauma Registry.

PURPOSE: There has been little to no literature published on combat-related genitourinary injuries beyond 2013. With the goal of enhancing medical readiness prior to deployment and making recommendations to improve the long-term rehabilitation of service members as they become civilians, we sought to describe the incidence of combat-related genitourinary injuries and interventions from January 1, 2007, to March 17, 2020. MATERIALS AND METHODS: We conducted a retrospective analysis of the Department of Defense Trauma Registry, which is a prospectively maintained database, for the time between 2007 and 2020. We used predefined search criteria to primarily identify any casualties that arrived at a military treatment facility with urological-based injuries. RESULTS: The registry contained 25,897 adult casualties, of which 7.2% sustained urological injuries. The median age was 25. Explosive injuries (64%) and firearms (27%) predominated. The median injury severity score was 18 (IQR 10-29). Most patients survived until hospital discharge (94%). The most frequently injured organs were the scrotum (60%), testes (53%), penis (30%), and kidneys (30%). Massive transfusion protocols were activated in 35% of all patients who sustained a urological injury and accounted for 28% of all protocols between 2007 and 2020. CONCLUSIONS: The incidence of genitourinary trauma persistently increased for both military and civilian personnel as the U.S. remained actively engaged in major military conflicts during this period. Patients with genitourinary trauma in this data set were often associated with high injury severity scores and required an increased number of immediate and long-term resources for survival and rehabilitation.

A prospective assessment of the time required to obtain one unit of fresh whole blood by civilian phlebotomists and Army laboratory technicians (68 K).

BACKGROUND: Resuscitation with blood products improves survival after major hemorrhage. Blood product administration at or near the point-of-injury (POI) amplifies this benefit. Size, weight, and cold-chain management challenges all limit the amount of blood medics can carry. Warm fresh whole blood (WFWB) transfusions from a pre-screened donor within the unit represent an alternative source of blood at the POI. We measured the time required for civilian and Army technicians performing phlebotomy frequently to obtain one unit of blood to serve as a goal metric for combat medics being trained in this skill. METHODS: We gathered demographic and experience data along with proportion of first intravenous cannulation attempt success, time to blood flow initiated, and time to unit draw complete. RESULTS: We prospectively enrolled 12 civilian phlebotomy technicians and 10 Army laboratory technicians performing whole blood collections on 50 and 68 donors respectively. The mean time from setup to needle insertion was 3.7 min for civilians versus 4.2 min for Army technicians. The mean time from blood flowing to the bag being full was 10.7 min versus 8.4 min for civilians versus Army technicians respectively. The mean bag weights were 514 g versus 522 g. First-pass intravenous cannulation success was 96% versus 98% respectively. CONCLUSIONS: We found a high first intravenous cannulation attempt success among both the civilian and Army technicians. Medians times were <5 min to obtain venipuncture and <11 min to obtain one unit. These findings provide time-based benchmarks for potential use during transfusion training among military medics.

A prospective assessment of the medic autologous blood transfusion skills for field transfusion preparation.

BACKGROUND: Data demonstrate the benefit of blood product administration near point-of-injury (POI). Fresh whole blood transfusion from a pre-screened donor provides a source of blood at the POI when resources are constrained. We captured transfusion skills data for medics performing autologous blood transfusion training. METHODS: We conducted a prospective, observational study of medics with varying levels of experience. Inexperienced medics were those with minimal or no reported experience learning the autologous transfusion procedures, versus reported experience among special operations medics. When available, medics were debriefed after the procedure for qualitative feedback. We followed them for up to 7 days for adverse events. RESULTS: The median number of attempts for inexperienced and experienced medics was 1 versus 1 (interquartile range 1-1 for both, p = .260). The inexperienced medics had a slower median time to needle venipuncture access for the donation of 7.3 versus 1.5 min, needle removal after clamping time of 0.3 versus 0.2 min, time to bag preparation of 1.9 versus 1.0 min, time to IV access for reinfusion of 6.0 versus 3.0 min, time to transfusion completion of 17.3 versus 11.0 min, and time to IV removal of 0.9 versus 0.3 min (all p < .05). We noted one administrative safety event in which an allogeneic transfusion occurred. No major adverse events occurred. Qualitative data saturated around the need for quarterly training. CONCLUSIONS: Inexperienced medics have longer procedure times when training autologous whole blood transfusion skills. This data will help establish training measures of performance for skills optimization when learning this procedure.

Hypothermia in the Combat Trauma Population.

BACKGROUND: The MARCH (Massive hemorrhage, Airway, Respirations, Circulation, and Hypothermia/Head injuries) algorithm taught to military medics includes interventions to prevent hypothermia. As possible sequelae from major trauma, hypothermia is associated with coagulopathy and lower survival. This paper sought to define hypothermia within our combat trauma population using an outcomes-based method, and determine clinical variables associated with hypothermia. METHODS: This is a secondary analysis of a previously described dataset from the Department of Defense Trauma Registry focused on casualties who received prehospital care. A receiver operating curve was constructed and Youden's index was used to define hypothermia within the predetermined population based on mortality risk. A multivariable regression model was used to identify associations. RESULTS: There were 23,243 encounters that met the inclusion criteria for this study with patients having received prehospital care and documentation of at least one emergency department temperature. An optimal threshold of 36.2° C was found to predict mortality; 3,159 casualties had temperatures below this threshold (14%). Survival to discharge was lower among casualties with hypothermia (91% versus 98%). Hypothermic casualties were less likely to undergo blanket application (38% versus 40%). However, they had higher proportions with Hypothermia Prevention and Management Kit application (11% versus 7%) and radiant warming (2% versus 1%). On multivariable regression modeling, none of the hypothermia interventions were associated with a decreased likelihood of hypothermia. Non-hypothermia interventions associated with hypothermia included prehospital intubation (OR 1.57, 95% CI 1.45-1.69) and blood product administration. CONCLUSIONS: Hypothermia, including a single recorded low temperature in the patient care record, was associated with worse outcomes in this combat trauma population. Prehospital intubation was most strongly associated with developing hypothermia. Prehospital warming interventions were not associated with a reduction in hypothermia risk. Our dataset suggests that current methods for prehospital warming are inadequate.

A Retrospective Analysis of Combat Injury Patterns and Prehospital Interventions Associated with the Development of Sepsis.

BACKGROUND: Combat injury related wound infections are common. Untreated, these wound infections may progress to sepsis and septic shock leading to increased morbidity and mortality rates. Understanding infectious complications, patterns, progression, and correlated prehospital interventions are vital to understand the development of sepsis. We aim to analyze demographics, injury patterns, and interventions associated with sepsis in battlefield settings. MATERIALS AND METHODS: This is a secondary analysis of previously published data from the Department of Defense Trauma Registry (DoDTR) from 2007 to 2020. We searched for casualties diagnosed with sepsis (excluding line-sepsis) throughout their initial hospitalization. Regression models were used to seek associations. RESULTS: Our initial request yielded 28,950 encounters, of which 25,654 (88.6%) were adults that met inclusion, including 243 patients (0.9%) diagnosed with sepsis. Patients included US military (34%), non-North Atlantic Treaty Organization (NATO) military (33%) and humanitarian (30%) groups. Patients diagnosed with sepsis had a significantly lower survival rate than non-septic patients (78.1% vs. 95.7%, p < 0.001). There was no significant difference in administration of prehospital antibiotics between septic and the general populations (10.6% vs. 12.3%, p = 0.395). Prehospital intraosseous access (OR 1.56, 95% CI 1.27-1.91, p = 0.207) and packed red cell administration (1.63, 1.24-2.15, 0.029) were the interventions most associated with sepsis. CONCLUSIONS: Sepsis occurred infrequently in the DoDTR when evacuation from battlefield is not delayed, but despite increased intervention frequency, developing sepsis demonstrates a significant drop in survival rates. Future research would benefit from the development of risk mitigation measures.

Condition of bob veal calves on arrival at an abattoir in Ohio.

Previous research has shown surplus dairy calves arrive at 'formula-fed' veal operations in North America in sub-optimal condition; however, little is known about the condition of 'bob' veal calves on arrival at abattoirs. The objectives of this study were to assess the condition of bob veal calves on arrival at an abattoir in Ohio and determine risk factors for poor health outcomes. On arrival, 35 calves in each of 12 cohorts (n = 420 calves) were assessed using a standardised health examination. A blood sample was also collected to assess failed transfer of passive immunity (FTPI) and hypoglycaemia. Descriptive statistics were used to describe the prevalence of poor health outcomes. Mixed-effects logistic regression models were used to identify if calf breed, sex, or source were risk factors for poor health outcomes. The most common physical health concern observed on arrival at the abattoir was dehydration (mean: 68.6%), followed by thin body condition (39.8%), and navel inflammation (25.7%). Approximately one-quarter (23.4%) of calves had FTPI and 73.4% were hypoglycaemic. Male calves were more likely than females to arrive hypoglycaemic. Hydration status was associated with breed; Jersey and crossbreed calves were less likely to be dehydrated than Holstein-Friesian calves. Buying station tended to be associated with FTPI. These results underline the need for more studies investigating morbidity, mortality, and their underlying risk factors to promote calf welfare prior to slaughter in each stage of the production chain: on the dairy farm of birth, during marketing, and in transit.

An analysis of early volume resuscitation and the association with prolonged mechanical ventilation.

BACKGROUND: Previous studies have found that intravenous fluid administration within the first 24 h may be associated with prolonged mechanical ventilation (PMV). We examined the association between initial 24 h fluids and PMV in combat casualties. METHODS: This is a secondary analysis of a previously described dataset from the Department of Defense Trauma Registry (DODTR). We included casualties with at least 24 h on the ventilator and no significant traumatic brain injury. The definition of PMV and associations were constructed using univariable and multivariable logistic regression models. RESULTS: We identified 1508 casualties available for analysis for this study - 1275 in the non-PMV cohort (<9 days on ventilator vs. 233 in the PMV cohort (≥9 days on ventilator). Explosives comprised the most common mechanism of injury for both groups (72% vs. 75%) followed by firearms (21% vs. 16%). The composite injury severity score (ISS) was lower in the non-PMV cohort (18 vs. 30, p < .001). There were lower volumes of all resuscitation fluid within the first 24 h in the non-PMV cohort. When adjusting for composite ISS and mechanism of injury in a multivariable logistic regression model with PMV as the outcome, crystalloid volume (unit odds ratio [UOR] 1.07) and colloid volume (UOR 1.03) were both associated with PMV. CONCLUSIONS: We found that volume of resuscitation fluids were substantially higher in the PMV cohort. Our findings suggest the need for caution with the routine use of crystalloid and colloid in the first 24 h of resuscitation.

An Analysis of 13 Years of Prehospital Combat Casualty Care: Implications for Maintaining a Ready Medical Force.

Background: Most potentially preventable deaths occur in the prehospital setting before reaching a military treatment facility with surgical capabilities. Thus, optimizing the care we deliver in the prehospital combat setting represents a ripe target for reducing mortality. We sought to analyze prehospital data within the Department of Defense Trauma Registry (DODTR). Materials and methods: We requested all encounters with any prehospital activity (e.g., interventions, transportation, vital signs) documented within the DODTR from January 2007 to March 2020 along with all hospital-based data that was available. We excluded from our search casualties that had no prehospital activity documented. Results: There were 28,950 encounters that met inclusion criteria. Of these, 25,897 (89.5%) were adults and 3053 were children (10.5%). There was a steady decline in the number of casualties encountered with the most notable decline occurring in 2014. U.S. military casualties comprised the largest proportion (n = 10,182) of subjects followed by host nation civilians (n = 9637). The median age was 24 years (interquartile range/IQR 21-29). Most were battle injuries (78.6%) and part of Operation ENDURING FREEDOM (61.8%) and Operation IRAQI FREEDOM (24.4%). Most sustained injuries from explosives (52.1%) followed by firearms (28.1%), with serious injury to the extremities (24.9%) occurring most frequently. The median injury severity score was 9 (IQR 4-16) with most surviving to discharge (95.0%). A minority had a documented medic or combat lifesaver (27.9%) in their chain of care, nor did they pass through an aid station (3.0%). Air evacuation predominated (77.9%). Conclusions: Within our dataset, the deployed U.S. military medical system provided prehospital medical care to at least 28,950 combat casualties consisting mostly of U.S. military personnel and host nation civilian care. There was a rapid decline in combat casualty volumes since 2014, however, on a per-encounter basis there was no apparent drop in procedural volume.

Characterizing pediatric supermassive transfusion and the contributing injury patterns in the combat environment.

BACKGROUND: Trauma is the leading cause of pediatric mortality in the United States. Often, these patients require supermassive transfusion (SMT), which we define as receipt of >80 mL/kg blood products, double the proposed volume for standard pediatric massive transfusion (MT). Evaluating the blood volumes, injury patterns, clinical findings, and prehospital interventions predictive for SMT are critical to reducing pediatric mortality. We describe the pediatric casualties, injury patterns, and clinical findings that comprise SMT. METHODS: We retrospectively analyzed pediatric trauma data from the Department of Defense Trauma Registry from January 2007-2016. We stratified patients into two cohorts based on blood products received in the first 24 h after injury: 1) those who received 40-80 mL/kg (MT), or 2) those who received >80 mL/kg (SMT). We evaluated demographics, injury patterns, prehospital interventions, and clinical findings. RESULTS: Our original dataset included 3439 pediatric casualties. We identified 536 patients who met inclusion parameters (receipt of ≥40 mL/kg of blood products [whole blood, packed red blood cells, fresh frozen plasma, platelets, or cryoprecipitate]). The MT cohort included 271 patients (50.6%), and the SMT cohort comprised 265 patients (49.4%). Survival to discharge was significantly lower (78% for SMT, 86% for MT; p < 0.011) in the SMT cohort. Multivariable analysis of injury patterns revealed serious injuries (Abbreviated Injury Scale 3-6) to the extremities (OR 2.13, 95% CI 1.45-3.12) and abdomen (OR 1.65, 1.08-2.53) were associated with SMT. Wound dressings (41% versus 29%; p = 0.003), tourniquets (23% vs 12%; p = 0.001), and IO access (17% vs 10%; p = 0.013) were more common in the SMT group. Age-adjusted hypotension was significantly higher in the SMT group (41%, n = 100 vs 23%, n = 59; p < 0.001) with no statistical difference detected in tachycardia (87%, n = 223 vs 87%, n = 228; p = 0.932). CONCLUSIONS: Our research demonstrates that pediatric SMT patients are at increased risk of mortality. Our study highlights the seriousness of extremity injuries in pediatric trauma patients, identifying associations between severe injuries to the extremities and abdomen with the receipt of SMT. Prehospital interventions of wound dressing, tourniquets, and IO access were more frequent in the SMT cohort. Our research determined that hypotension was associated with SMT, but tachycardia was not a reliable predictor of SMT over MT.

FINGER: A Novel Approach to Teaching Simple Thoracostomy.

For decades, most prehospital clinicians have only been armed with needle thoracostomy to treat a tension pneumothorax, which has a significant failure rate. Following recent changes by the US military, more ground and air transport agencies are adopting simple thoracostomy, also commonly referred to as finger thoracostomy, as a successful alternative. However, surgical procedures performed by prehospital clinicians remain uncommon, intimidating, and challenging. Therefore, it is imperative to adopt a training strategy that is comprehensive, concise, and memorable to best reduce cognitive load on clinicians while in a high-acuity, low-frequency situation. We suggest the following mnemonic to aid in learning and retention of the key procedural steps: FINGER (Find landmarks; Inject lidocaine/pain medicine; No infection allowed; Generous incision; Enter pleural space; Reach in with finger, sweep, reassess). This teaching aid may help develop and maintain competence in the simple thoracostomy procedure, leading to successful treatment of both a tension pneumothorax and hemothorax.

More sophisticated than a drink cooler or an old sphygmomanometer but still not adequate for prehospital blood: A market review of commercially available equipment for prehospital blood transport and administration.

BACKGROUND: Hemorrhage is the leading cause of death in trauma patients with most fatalities occurring before reaching a higher level of care-this applies to both the civilian setting and the military combat setting. Hemostatic resuscitation with increased emphasis on blood transfusion while limiting use of crystalloids has become routine in trauma care. However, the prehospital setting-especially in combat-presents unique challenges with regard to storage, transport, and administration. We sought to evaluate available technology on the market for storage and administration technology that is relevant to the prehospital setting. STUDY DESIGN AND METHODS: We conducted a market review of available technology through subject-matter expert inquiry, reviews of published literature, reviews of Federal Drug Administration databases, internal military publications, and searches of Google. RESULTS: We reviewed and described a total of 103 blood transporters, 22 infusers, and 6 warmers. CONCLUSIONS: The risk of on-scene fatality in trauma patients and recent developments in trauma care demonstrate the need for prehospital transfusion. These transfusions have been logistically prohibited in many operations. We have reviewed the current commercially available equipment and recommended pursuit of equipment that improves accessibility to field transfusion. Current technology has limited applicability for the prehospital setting and is further limited for the military setting.

An analysis of outcomes for pediatric trauma warm fresh whole blood recipients in Iraq and Afghanistan.

BACKGROUND: Whole blood therapy-which contains the ideal balance of components, and particularly fresh whole blood-has been shown to be beneficial in adult trauma. It remains unclear whether there is potential benefit in the pediatric population. STUDY DESIGN AND METHODS: This is a secondary analysis of previously published data analyzing pediatric casualties undergoing massive transfusion in the Department of Defense Trauma Registry. Pediatric patients with traumatic injury who were transfused at least one blood product were included in the analysis. We compared children who received component therapy exclusively to those who received any amount of warm fresh whole blood. RESULTS: Of the 3439 pediatric casualties within our dataset, 1244 were transfused at least one blood product within the first 24 h. There were 848 patients without severe head injury. Within this cohort, 23 children received warm fresh whole blood overall, 20 of whom did not have severe head injury. In an adjusted analysis, the odds ratio (95% confidence interval [CI]) for survival for warm fresh whole blood recipients was 2.86 (0.40-20.45). After removing children with severe brain injury, there was an independent association with improved survival for warm fresh whole blood recipients with an odds ratio (95% CI) of 58.63 (2.70-1272.67). DISCUSSION: Our data suggest that warm fresh whole blood may be associated with improved survival in children without severe head injury. Larger prospective studies are needed to assess the efficacy and safety of whole blood in children with severe traumatic bleeding.

Prehospital Vasopressor Use Is Associated with Worse Mortality in Combat Wounded.

INTRODUCTION: Vasopressor medications are frequently used in the management of hypotension secondary to shock. However, little data exists regarding their use in hypotensive trauma patients and their use is controversial. METHODS: The Department of Defense Trauma Registry was queried from January 2007 to August 2016 using a series of procedural codes to identify eligible casualties, which has been previously described. Mortality was compared between hypotensive casualties with documentation of receipt of vasopressor medications versus casualties not receiving vasopressors. To control for potential confounders, comparisons were repeated by constructing a multivariable logistic regression model that utilized patient category, mechanism of injury, composite injury severity score, total blood products transfused, prehospital heart rate and prehospital systolic pressure. Survival was compared between these groups using propensity matching. RESULTS: Our search strategy yielded 28,222 patients, 124 (0.4%) of whom received prehospital vasopressors. On univariable analysis vasopressor use was associated with lower odds of survival (OR 0.09, 0.06-0.13). The lower odds of survival persisted in the multivariate logistic regression model (OR 0.32, 0.18-0.56). Survival was lower among the vasopressor group (71.3%) when compared to a propensity matched cohort (94.3%). CONCLUSIONS: In this dataset, prehospital vasopressor use was associated with lower odds of survival. This finding persisted when adjusting for confounders and in a propensity matched cohort model.

Vital sign thresholds predictive of death in the combat setting.

INTRODUCTION: Identifying patients at imminent risk of death is a paramount priority in combat casualty care. This study measures the vital sign values predictive of mortality among combat casualties in Iraq and Afghanistan. METHODS: We used data from the Department of Defense Trauma Registry from January 2007 to August 2016. We used the highest documented heart rate and the lowest documented systolic pressure in the emergency department for each casualty. We constructed receiver operator curves (ROCs) to assess the accuracy of these variables for predicting survival to hospital discharge. RESULTS: There were 38,769 encounters of which our dataset included 15,540 (40.1%). The median age of these patients was 25 years and 97.5% were male. The most common mechanisms of injury were explosives (n = 9481, 61.0%) followed by gunshot wounds (n = 2393, 15.3%). The survival rate to hospital discharge was 97.5%. The median heart rate was 94 beats per minute (bpm) with area under the ROC of 0.631 with an optimal threshold to predict mortality of 110 bpm (sensitivity 52.2%, specificity 79.2%). The median systolic blood pressure was 128 mmHg with area under the ROC of 0.790 with an optimal threshold to predict mortality of 112 mmHg (sensitivity 68.5%, specificity 81.5%). CONCLUSIONS: Casualties with a systolic blood pressure <112 mmHg, are at high risk of mortality, a value significantly higher than the traditional 90 mmHg threshold. Our dataset highlights the need for better methods to guide resuscitation as vital sign measurements have limited accuracy in predicting mortality.

Implementation of a low titer group O whole blood program for a law enforcement tactical team.

The Texas Ranger Special Operations Group (SOG) performs high-risk warrant service and responds to callouts for evolving kinetic situations and special missions as required. These operations may occur many hours from a trauma center. Fresh whole blood (FWB) transfusions may offer a stopgap for those who are critically injured. To make FWB transfusions a viable option, several steps must be implemented. The following lays out how the Texas Ranger SOG will implement and conduct FWB transfusions using low titer group O whole blood. The techniques outlined may be useful for communities that may face critical blood shortage in disasters.