Prehospital whole blood reduces early mortality in patients with hemorrhagic shock.

BACKGROUND: Low titer O+ whole blood (LTOWB) is being increasingly used for resuscitation of hemorrhagic shock in military and civilian settings. The objective of this study was to identify the impact of prehospital LTOWB on survival for patients in shock receiving prehospital LTOWB transfusion. STUDY DESIGN AND METHODS: A single institutional trauma registry was queried for patients undergoing prehospital transfusion between 2015 and 2019. Patients were stratified based on prehospital LTOWB transfusion (PHT) or no prehospital transfusion (NT). Outcomes measured included emergency department (ED), 6-h and hospital mortality, change in shock index (SI), and incidence of massive transfusion. Statistical analyses were performed. RESULTS: A total of 538 patients met inclusion criteria. Patients undergoing PHT had worse shock physiology (median SI 1.25 vs. 0.95, p < .001) with greater reversal of shock upon arrival (-0.28 vs. -0.002, p < .001). In a propensity-matched group of 214 patients with prehospital shock, 58 patients underwent PHT and 156 did not. Demographics were similar between the groups. Mean improvement in SI between scene and ED was greatest for patients in the PHT group with a lower trauma bay mortality (0% vs. 7%, p = .04). No survival benefit for patients in prehospital cardiac arrest receiving LTOWB was found (p > .05). DISCUSSION: This study demonstrated that trauma patients who received prehospital LTOWB transfusion had a greater improvement in SI and a reduction in early mortality. Patient with prehospital cardiac arrest did not have an improvement in survival. These findings support LTOWB use in the prehospital setting. Further multi-institutional prospective studies are needed.

Prehospital shock index and systolic blood pressure are highly specific for pediatric massive transfusion.

BACKGROUND: While massive transfusion protocols (MTPs) are associated with decreased mortality in adult trauma patients, there is limited research on the impact of MTP on pediatric trauma patients. The purpose of this study was to compare pediatric trauma patients requiring massive transfusion with all other pediatric trauma patients to identify triggers for MTP activation in injured children. METHODS: Using our level I trauma center's registry, we retrospectively identified all pediatric trauma patients from January 2015 to January 2018. Massive transfusion (MT) was defined as infusion of 40 mL/kg of blood products in the first 24 hours of admission. Patients missing prehospital vital sign data were excluded from the study. We retrospectively collected data including demographics, blood utilization, variable outcome data, prehospital vital signs, prehospital transport times, and Injury Severity Scores. Statistical significance was determined using Mann-Whitney U test and χ2 test. p Values of less than 0.05 were considered significant. RESULTS: Thirty-nine (1.9%) of the 2,035 pediatric patients met the criteria for MT. All-cause mortality in MT patients was 49% (19 of 39 patients) versus 0.01% (20 of 1996 patients) in non-MT patients. The two groups significantly differed in Injury Severity Score, prehospital vital signs, and outcome data.Both systolic blood pressure (SBP) of <100 mm Hg and shock index (SI) of >1.4 were found to be highly specific for MT with specificities of 86% and 92%, respectively. The combination of SBP of <100 mm Hg and SI of >1.4 had a specificity of 94%. The positive and negative predictive values of SBP of <100 mm Hg and SI of >1.4 in predicting MT were 18% and 98%, respectively. Based on positive likelihood ratios, patients with both SBP of <100 mm Hg and SI of >1.4 were 7.2 times more likely to require MT than patients who did not meet both of these vital sign criteria. CONCLUSION: Pediatric trauma patients requiring early blood transfusion present with lower blood pressures and higher heart rates, as well as higher SIs and lower pulse pressures. We found that SI and SBP are highly specific tools with promising likelihood ratios that could be used to identify patients requiring early transfusion. LEVEL OF EVIDENCE: Therapeutic/care management, level V.

Shock index and pulse pressure as triggers for massive transfusion.

BACKGROUND: Hemorrhage is the most common cause of preventable death in trauma patients. These mortalities might be prevented with prehospital transfusion. We sought to characterize injured patients requiring massive transfusion to determine the potential impact of a prehospital whole blood transfusion program. The primary goal of this analysis was to determine a method to identify patients at risk of massive transfusion in the prehospital environment. Many of the existing predictive models require laboratory values and/or sonographic evaluation of the patient after arrival at the hospital. Development of an algorithm to predict massive transfusion protocol (MTP) activation could lead to an easy-to-use tool for prehospital personnel to determine when a patient needs blood transfusion. METHODS: Using our Level I trauma center's registry, we retrospectively identified all adult trauma patients from January 2015 to August 2017 requiring activation of the MTP. Patients who were younger than 18 years, older than 89 years, prisoners, pregnant women, and/or with nontraumatic hemorrhage were excluded from the study. We retrospectively collected data including demographics, blood utilization, variable outcome data (survival, length of stay, intensive care unit days, ventilator days), prehospital vital signs, prehospital transport times, and Injury Severity Score. The independent-samples t test and χ test were used to compare the group who died to the group who survived. p < 0.05 was considered significant. Based on age and mechanism of injury, relative risk of death was calculated. Graphs were generated using Microsoft Excel software to plot patient variables. RESULTS: Our study population of 102 MTP patients had an average age of 42 years and average Injury Severity Score of 29, consisted of 80% males (82/102), and was 66% blunt trauma (67/102). The all-cause mortality was 67% (68/102). The positive predictive value of death for patients with pulse pressure of less than 45 and shock index of greater than 1 was 0.78 for all patients, but was 0.79 and 0.92 for blunt injury and elderly patients, respectively. CONCLUSIONS: Our data demonstrate a high mortality rate in trauma patients who require MTP despite short transport times, indicating the need for early intervention in the prehospital environment. Given our understanding that the most severely injured patients in hemorrhagic shock require blood resuscitation, this study demonstrates that this subset of trauma patients requiring massive transfusion can be identified in the prehospital setting. We recommend using Emergency Medical Services pulse pressure in combination with shock index to serve as a trigger for initiation of prehospital whole blood transfusion. LEVEL OF EVIDENCE: Therapeutic/care management, level V.

Give the trauma patient what they bleed, when and where they need it: establishing a comprehensive regional system of resuscitation based on patient need utilizing cold-stored, low-titer O+ whole blood.

BACKGROUND: Despite countless advancements in trauma care a survivability gap still exists in the prehospital setting. Military studies clearly identify hemorrhage as the leading cause of potentially survivable prehospital death. Shifting resuscitation from the hospital to the point of injury has shown great promise in decreasing mortality among the severely injured. MATERIALS AND METHODS: Our regional trauma network (Southwest Texas Regional Advisory Council) developed and implemented a multiphased approach toward facilitating remote damage control resuscitation. This approach required placing low-titer O+ whole blood (LTO+ WB) at helicopter emergency medical service bases, transitioning hospital-based trauma resuscitation from component therapy to the use of whole blood, modifying select ground-based units to carry and administer whole blood at the scene of an accident, and altering the practices of our blood bank to support our new initiative. In addition, we had to provide information and training to an entire large urban emergency medical system regarding changes in policy. RESULTS: Through a thorough, structured program we were able to successfully implement point-of-injury resuscitation with LTO+ WB. Preliminary evaluation of our first 25 patients has shown a marked decrease in mortality compared to our historic rate using component therapy or crystalloid solutions. Additionally, we have had zero transfusion reactions or seroconversions. CONCLUSION: Transfusion at the scene within minutes of injury has the potential to save lives. As our utilization expands to our outlying network we expect to see a continued decrease in mortality among significantly injured trauma patients.

Bigger is better: Comparison of alternative devices for tension hemopneumothorax and pulseless electrical activity in a Yorkshire swine model.

BACKGROUND: Tension pneumothorax is a cause of potentially preventable death in prehospital and battlefield settings and 14-gauge angiocatheter (14G AC) decompression remains the current treatment standard, despite its high incidence of failure. Traumatic pneumothorax is often associated with hemothorax, but 14G AC has no proven efficacy for associated hemothorax. We sought to compare the 14G AC to three alternative devices for treatment of tension hemopneumothorax (t-H/PTX) in a positive-pressure ventilation swine model. METHODS: Our tension model was modified to incorporate a persistent air leak and pleural blood. Tension physiology was achieved with escalating carbon dioxide insufflation via transdiaphragmatic trocar, and 10% estimated blood volume was instilled into each chest. Intervention was randomized between 14G AC, 10-gauge angiocatheter (10G AC), modified Veress-type needle (mVN), and 3-mm laparoscopic trocar (LT). After recovery, serial tension-induced pulseless electrical activity (PEA) events were induced and decompressed. Success of rescue, time to rescue, and physiologic data were recorded. RESULTS: One hundred ninety-five t-H/PTX and 88 PEA events were conducted in 25 swine. Laparoscopic trocar and 10G AC were more successful and had faster median time to rescue for t-H/PTX compared with 14G AC, whereas mVN performed comparably. Following PEA, 14G AC and mVN succeeded at rescue only 50% and 57% of the time, whereas 10G AC and LT had 100% success at return of spontaneous circulation. Time to successful return of circulation following PEA did not differ between devices; however, there was a noticeable difference in the rate of meaningful hemodynamic recovery following PEA favoring LT and 10G AC. There were no significant injuries noted. CONCLUSIONS: While mVN performed comparably to 14G AC, both have unacceptable failure rates. Ten-gauge AC and LT performed superiorly in both t-H/PTX and PEA. We believe there is now ample evidence supporting replacement of the 14G AC with 10G AC in current treatment recommendations.