Characteristics and Outcomes of Prehospital Tourniquet Use for Trauma in the United States.

INTRODUCTION: The use of the extremity tourniquet in military environments has reduced preventable deaths due to exsanguinating hemorrhage, leading to increased use in civilian settings. However, the outcomes of contemporary prehospital tourniquet use in civilian settings are not well-described nationally. The objective of this study was to describe the characteristics and outcomes following prehospital tourniquet use by emergency medical services (EMS) in the United States. METHODS: All trauma activations reported to the National EMS Information System 2019 (NEMSIS) were included. Patients who had ≥1 tourniquet applied were identified. Descriptive analyses were used to compare characteristics between tourniquet and no-tourniquet cohorts. Coarsened exact matching was performed to generate a k2k match (on age, sex, lowest-systolic blood pressure, initial patient acuity, provider's initial impression, injury mechanism, and presence of upper/lower extremity injuries) and used to compare outcomes. Trauma patients who may have potentially benefited from tourniquet application (extremity injury, shock index ≥1 and no documented tourniquet application) were identified. RESULTS: A total of 7,161 tourniquets were applied among 4,571,379 trauma activations (1.6/1000 activations). Patients in the tourniquet cohort were younger (40 ± 18 vs 52 ± 26 mean ± SD years), more hypotensive (16.1% vs. 2.5%) and had higher initial acuity (65.0% critical/emergent vs. 20.6%) [p < 0.01 for all]. A total of 7,074 patients in the tourniquet cohort were matched with 7,074 patients in the non-tourniquet cohort. Post-match analysis revealed that the patients in tourniquet cohort had a higher final acuity (80.8% vs. 75.0%, p < 0.01), lower scene-time (15.4 ± 13.6 vs. 17.0 ± 14.2 mean ± SD minutes, p < 0.01), and higher survival-to-hospital (83.6% vs. 75.1%, p < 0.01). A total of 141,471 trauma patients who may have potentially benefited from tourniquet application were identified. CONCLUSION: Prehospital tourniquet use by EMS in the United States is associated with lower scene-time and improved survivability to hospital. Results indicate that patients might benefit from wider tourniquet use in the civilian prehospital setting.

Nationwide estimates of the need for prehospital blood products after injury.

INTRODUCTION: Prehospital blood product resuscitation after injury significantly decreases risk of mortality. However, the number of patients who may potentially benefit from this life-saving intervention is currently unknown. The primary objective of this study was to estimate the number of patients who may potentially benefit from prehospital blood product resuscitation after injury in the United States. The secondary objective was to estimate the amount of blood products needed for prehospital resuscitation of injured patients. METHODS: Patients ≥16 years with blunt/penetrating injuries included in National Emergency Medical Services Information System 2019 were identified and classified into four separate cohorts of hemodynamic instability: Cohort 1 (systolic blood pressure [SBP] <90 mmHg), Cohort 2 (SBP <90 and/or heart rate [HR] >120), Cohort 3 (SBP <90 and HR >108 or SBP <70), and Cohort 4 (shock index ≥1). The need for prehospital blood was estimated by multiplying number of patients in each cohort with average number of blood products used for prehospital resuscitation. RESULTS: After exclusions, 3.7 million adult trauma patients were included. The number of patients who may potentially benefit from prehospital blood products was estimated as 89,391 (Cohort 1), 901,346 (Cohort 2), 54,160 (Cohort 3), and 300,475 (Cohort 4). Assuming 1 unit of whole blood is needed per patient, a lower-bound estimate of 54,160 additional whole blood units (0.6% of current collections) will be need for prehospital resuscitation of the injured. CONCLUSIONS: Annually, between 54,000 and 900,000 patients may potentially benefit from prehospital blood product resuscitation after injury in the United States. Prehospital blood utilization and collection of blood products will need to be increased to scale-up this life-saving intervention nationwide.

Over-transfusion with blood for suspected hemorrhagic shock is not associated with worse clinical outcomes.

BACKGROUND: We evaluated patient outcomes after early, small volume red blood cell (RBC) transfusion in the setting of presumed hemorrhagic shock. We hypothesized that transfusion with even small amounts of blood would be associated with more complications. STUDY DESIGN AND METHODS: Retrospective review of trauma patients admitted to a Level 1 trauma center between 2016-2021. Patients predicted to require massive transfusion who survived ≥72 h were categorized according to units of RBCs transfused in the first 24 h. A Cox regression model stratified by dichotomized ISS and adjusted for SBP <90 mm Hg and pulse >120 bpm on arrival was used to estimate hazard ratios (HRs) for outcomes of interest. RESULTS: A total of 3121 (24%) received RBC transfusion within the first 24 h. Massive transfusion protocol (MTP) was activated in 38% (1188/3121): 17% received no RBCs, 27.4% 1-3 units, 32.4% 4-9 units, and 22.7% ≥10 units. Mean ISS increased with each category of RBC transfusion. There was no difference in the risk of acute kidney injury (AKI), acute respiratory distress syndrome (ARDS), infection, cardiac arrest, venous thromboembolism or stroke for patients receiving 1-3 units compared to the non-transfused group or 4-9 units group (p > 0.05). Compared to those receiving ≥10 units, the 1-3 units group had a significantly lower risk of AKI, ARDS, and cardiac arrest. DISCUSSION: Early empiric RBC transfusion for presumed hemorrhagic shock may subject patients to potential over-transfusion and end-organ damage. Among patients meeting clinical triggers for MTP, 1-3 units of allogeneic RBCs is not associated with worse outcomes.

How Does Mission Ground Time Impact on Population Coverage of Aeromedical Retrieval Systems?

BACKGROUND: Aeromedical retrieval is an essential component of contemporary emergency care systems. However, in many locations, ground emergency medical services are dispatched to the scene of an incident first to assess the patient and then call for a helicopter if needed. The time to definitive care therefore includes the helicopter's flight to the scene, flight to the trauma center, and nonflying time. Mission ground time (MGT) includes the time required to get the helicopter airborne, as well as time spent at the scene, packaging and loading the casualty into the aircraft. Estimates of MGT typically vary from 10 to 30 min. The impact of MGT duration on population coverage-the number of residents that could be taken to a trauma center within a set time-is not known. The aim of this study was to compare population coverage for different durations of MGT in a single state. METHODS: Coverage was calculated using elliptical coverage areas ("isochrones") based on the location of helicopter bases and Level I and Level II trauma centers. The calculations were performed using Microsoft Excel, assuming a cruising speed of 133 knots (246 km/h), and mapped using arcGIS. The access time threshold was set at 60 min, and we evaluated MGTs of 10, 15, 20, 25, and 30 min. RESULTS: MGT has a marked impact on population coverage. The effect is, furthermore, not linear. When considering the state's three Level I trauma centers, decreasing MGT from 30 to 10 min increased population coverage from 61.2% to 84.2%. When also considering Level II centers, decreasing MGT from 30 min to 10 min increased coverage by 20%. CONCLUSIONS: Elliptical isochrones, with allowance for MGT, provide realistic estimates of population coverage. MGT significantly impacts the proportion of the population that can be taken to a Level I and/or Level II Trauma Center within a set time. The impact is not linear, reflecting the uneven distribution of the population. Consideration should be given to minimizing MGT to preserve the benefits of aeromedical retrieval.

The Evolution of Blood Transfusion in the Trauma Patient: Whole Blood Has Come Full Circle.

Whole blood transfusion in the United States dates back to the Civil War, and it was widely used in all major conflicts since World War I. To understand our current civilian transfusion practices and to anticipate future changes in trauma resuscitation, it is important to understand the series of decisions that led trauma surgeons away from whole blood resuscitation and toward component therapy. In this review, we examine the historical basis for blood transfusion in trauma and examine the recent literature and future directions pertaining to blood product resuscitation in hemorrhaging patients.

Secondary Overtriage of Trauma Patients: Analysis of Clinical and Geographic Patterns.

BACKGROUND: The purpose of a trauma system is to match patients' needs with hospitals' ability to care for them, recognizing that the highest levels of care cannot be provided in all locations. This means that some patients will need to be transferred from a local facility to a higher level of care. Unnecessary transfers are expensive and inconvenient to patients and families. The aim of this study is to analyze the pattern of secondary transfers in a regional trauma system. METHODS: This is a retrospective analysis. We included patients aged 16 y and older who were transferred to University of Alabama at Birmingham Hospital between 2014 and 2018. We conducted bivariate and multivariate logistic regression analysis to identify clinical and organizational predictors of requiring a critical intervention, early discharge, intensive care unit admission, and mortality. Rather than treating each injury as isolated, we analyzed injury patterns. RESULTS: A total of3824 patients met the inclusion criteria. Of them, 664 patients (17.4%) required a critical intervention, 635 (16.6%) were discharged within 24 h, 1356 (35.5%) were admitted to the intensive care unit, and 172 (4.0%) patients died. Univariate and multivariate analyses revealed many positive associations, with regard to injury pattern, originating center, and insurance status. CONCLUSIONS: There are patterns in the data, and further study is required to understand drivers of secondary overtriage, and how we might be able to address this problem. Reducing the number of unnecessary transfers is a difficult task, which will require engagement at all levels of the trauma system.

Correction: Role of heme in lung bacterial infection after trauma hemorrhage and stored red blood cell transfusion: A preclinical experimental study.

[This corrects the article DOI: 10.1371/journal.pmed.1002522.].

Complications Associated With Placement of Chest Tubes: A Trauma System Perspective.

BACKGROUND: The insertion of a chest tube is a common procedure in trauma care, and the Advanced Trauma Life Support program teaches the insertion of chest tubes as an essential and life-saving skill. It is also recognized that the insertion of chest tubes is not without risks or complications. The purpose of this study was to evaluate complications of chest tube placement in a level 1 trauma center compared with those placed in surrounding referral hospitals. METHODS: A retrospective matched cohort study of trauma patients was performed between those who underwent chest tube placement at the level 1 trauma center and those with a chest tube placed before transfer to the level 1 center between 2004 and 2013. Conditional logistic regression was used to compare the likelihood of complications and death between chest tube placement groups. RESULTS: Four thousand two hundred and sixteen trauma patients had a chest tube placed at the level 1 center, and 364 patients had a chest tube placed at an outside hospital before transfer. Two hundred and eighty-one patients were matched. Patients with a chest tube placed outside the trauma center had an increased likelihood of malposition (OR 7.2, 95% CI 3.6-14.6), residual hemothorax (OR 6.3, 95% CI 3.4-11.6), residual pneumothorax (OR 6.7, 95% CI 3.9-11.4), and having a second chest tube placed (OR 3.77, 95% CI 2.37-6.01). However, the patients with a chest tube placed outside of the trauma center were also less likely to develop pneumonia (OR 0.32, 95% CI 0.14-0.73). There were no differences in the odds of developing an empyema, the need for video-assisted thoracoscopic surgery, thoracotomy, or death. CONCLUSIONS: There are opportunities for improving the care of patients who require chest tubes at both referring hospitals and the receiving trauma center. Improving the care of patients who require intercostal drainage requires a systems-based approach, focusing on training and quality improvement.

Older Blood Is Associated With Increased Mortality and Adverse Events in Massively Transfused Trauma Patients: Secondary Analysis of the PROPPR Trial.

STUDY OBJECTIVE: The transfusion of older packed RBCs may be harmful in critically ill patients. We seek to determine the association between packed RBC age and mortality among trauma patients requiring massive packed RBC transfusion. METHODS: We analyzed data from the Pragmatic, Randomized Optimal Platelet and Plasma Ratios trial. Subjects in the parent trial included critically injured adult patients admitted to 1 of 12 North American Level I trauma centers who received at least 1 unit of packed RBCs and were predicted to require massive blood transfusion. The primary exposure was volume of packed RBC units transfused during the first 24 hours of hospitalization, stratified by packed RBC age category: 0 to 7 days, 8 to 14 days, 15 to 21 days, and greater than or equal to 22 days. The primary outcome was 24-hour mortality. We evaluated the association between transfused volume of each packed RBC age category and 24-hour survival, using random-effects logistic regression, adjusting for total packed RBC volume, patient age, sex, race, mechanism of injury, Injury Severity Score, Revised Trauma Score, clinical site, and trial treatment group. RESULTS: The 678 patients included in the analysis received a total of 8,830 packed RBC units. One hundred patients (14.8%) died within the first 24 hours. On multivariable analysis, the number of packed RBCs greater than or equal to 22 days old was independently associated with increased 24-hour mortality (adjusted odds ratio [OR] 1.05 per packed RBC unit; 95% confidence interval [CI] 1.01 to 1.08): OR 0.97 for 0 to 7 days old (95% CI 0.88 to 1.08), OR 1.04 for 8 to 14 days old (95% CI 0.99 to 1.09), and OR 1.02 for 15 to 21 days old (95% CI 0.98 to 1.06). Results of sensitivity analyses were similar only among patients who received greater than or equal to 10 packed RBC units. CONCLUSION: Increasing quantities of older packed RBCs are associated with increased likelihood of 24-hour mortality in trauma patients receiving massive packed RBC transfusion (≥10 units), but not in those who receive fewer than 10 units.

Evaluation of "Stop the Bleed" training among K-12 faculty and staff in Alabama.

OBJECTIVES: To evaluate "Stop the Bleed" (STB) training among/K12 personnel in an Alabama school system, and to assess participants' perceived readiness to train peers in STB methods. DESIGN AND SAMPLE: We performed a cross-sectional observational study with a convenience, nonprobability sample of 466 full-time personnel who received STB training. Data were collected using an anonymous online survey. MEASUREMENTS: We asked participants to recall feelings related to STB both prior to and after completing training using a 5-point Likert scale (5 = "Strongly Disagree", 1 = "Strongly Agree"). We used logistic regression to evaluate the association among posttraining feelings and perceived preparedness to train others in STB. RESULTS: Participants were primarily female (78%), aged 41 ± 10 years, who held faculty positions (94%). Results revealed increased knowledge of (4 [IQR 2-4] vs. 2 [1-2], p < .001) and comfort with (4 [2-5] vs. 2 [1-2], p < .001) STB skills. Participants felt more empowered to organize STB training (4 [3-5] vs. 3 [2-4], p < .001); those who felt empowered to organize STB training were eight times more likely to feel capable of teaching STB. CONCLUSIONS: After STB training, K-12 personnel felt empowered to organize additional STB trainings and capable of teaching STB methods to others.

Role of heme in lung bacterial infection after trauma hemorrhage and stored red blood cell transfusion: A preclinical experimental study.

BACKGROUND: Trauma is the leading cause of death and disability in patients aged 1-46 y. Severely injured patients experience considerable blood loss and hemorrhagic shock requiring treatment with massive transfusion of red blood cells (RBCs). Preclinical and retrospective human studies in trauma patients have suggested that poorer therapeutic efficacy, increased severity of organ injury, and increased bacterial infection are associated with transfusion of large volumes of stored RBCs, although the mechanisms are not fully understood. METHODS AND FINDINGS: We developed a murine model of trauma hemorrhage (TH) followed by resuscitation with plasma and leukoreduced RBCs (in a 1:1 ratio) that were banked for 0 (fresh) or 14 (stored) days. Two days later, lungs were infected with Pseudomonas aeruginosa K-strain (PAK). Resuscitation with stored RBCs significantly increased the severity of lung injury caused by P. aeruginosa, as demonstrated by higher mortality (median survival 35 h for fresh RBC group and 8 h for stored RBC group; p < 0.001), increased pulmonary edema (mean [95% CI] 106.4 µl [88.5-124.3] for fresh RBCs and 192.5 µl [140.9-244.0] for stored RBCs; p = 0.003), and higher bacterial numbers in the lung (mean [95% CI] 1.2 × 10(7) [-1.0 × 10(7) to 2.5 × 10(7)] for fresh RBCs and 3.6 × 10(7) [2.5 × 10(7) to 4.7 × 10(7)] for stored RBCs; p = 0.014). The mechanism underlying this increased infection susceptibility and severity was free-heme-dependent, as recombinant hemopexin or pharmacological inhibition or genetic deletion of toll-like receptor 4 (TLR4) during TH and resuscitation completely prevented P. aeruginosa-induced mortality after stored RBC transfusion (p < 0.001 for all groups relative to stored RBC group). Evidence from studies transfusing fresh and stored RBCs mixed with stored and fresh RBC supernatants, respectively, indicated that heme arising both during storage and from RBC hemolysis post-resuscitation plays a role in increased mortality after PAK (p < 0.001). Heme also increased endothelial permeability and inhibited macrophage-dependent phagocytosis in cultured cells. Stored RBCs also increased circulating high mobility group box 1 (HMGB1; mean [95% CI] 15.4 ng/ml [6.7-24.0] for fresh RBCs and 50.3 ng/ml [12.3-88.2] for stored RBCs), and anti-HMGB1 blocking antibody protected against PAK-induced mortality in vivo (p = 0.001) and restored macrophage-dependent phagocytosis of P. aeruginosa in vitro. Finally, we showed that TH patients, admitted to the University of Alabama at Birmingham ER between 1 January 2015 and 30 April 2016 (n = 50), received high micromolar-millimolar levels of heme proportional to the number of units transfused, sufficient to overwhelm endogenous hemopexin levels early after TH and resuscitation. Limitations of the study include lack of assessment of temporal changes in different products of hemolysis after resuscitation and the small sample size precluding testing of associations between heme levels and adverse outcomes in resuscitated TH patients. CONCLUSIONS: We provide evidence that large volume resuscitation with stored blood, compared to fresh blood, in mice increases mortality from subsequent pneumonia, which occurs via mechanisms sensitive to hemopexin and TLR4 and HMGB1 inhibition.

A decompositional analysis of firearm-related mortality in the United States, 2001-2012.

Prior literature reporting increased rates of firearm-related homicide and suicide with increasing firearm availability is limited by only examining the availability of firearms, which is only one component of firearm-related mortality. The objective of the current study is to separate the rates into their respective components and determine which components contribute to mortality rate changes. To address the objective, nationally representative data from 2001 to 2012 was collected from a variety of publicly-available sources. Utilizing decompositional methodology, a negative binomial regression was used to estimate rate ratios for the association between the components and year category, and relative contributions of each component were calculated. From 2001 to 2012, the homicide and unintentional mortality rate decreased while the suicide rate increased. The suicide rate was only the firearm prevalence rate. The unintentional mortality rate was a factor of firearm prevalence, injury incidence, and case fatality rate. The homicide rate was a factor of firearm prevalence, violent crime rate, injury incidence, and case fatality rate. The current results suggest that the contributors of changes in firearm-related mortality are multi-faceted. Future studies should perform a decompositional analysis utilizing more granular data to examine whether the currently reported results are true associations or a factor of ecologic fallacy.

Acute brain trauma, lung injury, and pneumonia: more than just altered mental status and decreased airway protection.

Traumatic brain injury (TBI) is a major cause of mortality and morbidity worldwide. Even when patients survive the initial insult, there is significant morbidity and mortality secondary to subsequent pulmonary edema, acute lung injury (ALI), and nosocomial pneumonia. Whereas the relationship between TBI and secondary pulmonary complications is recognized, little is known about the mechanistic interplay of the two phenomena. Changes in mental status secondary to acute brain injury certainly impair airway- and lung-protective mechanisms. However, clinical and translational evidence suggests that more specific neuronal and cellular mechanisms contribute to impaired systemic and lung immunity that increases the risk of TBI-mediated lung injury and infection. To better understand the cellular mechanisms of that immune impairment, we review here the current clinical data that support TBI-induced impairment of systemic and lung immunity. Furthermore, we also review the animal models that attempt to reproduce human TBI. Additionally, we examine the possible role of damage-associated molecular patterns, the chlolinergic anti-inflammatory pathway, and sex dimorphism in post-TBI ALI. In the last part of the review, we discuss current treatments and future pharmacological therapies, including fever control, tracheostomy, and corticosteroids, aimed to prevent and treat pulmonary edema, ALI, and nosocomial pneumonia after TBI.

Validity of the Braden Scale in grading pressure ulcers in trauma and burn patients.

BACKGROUND: Pressure ulcers are a costly hospital-acquired condition in terms of clinical outcome and expense. The Braden Scale was developed in 1987 as a risk scoring method for pressure ulcers and uses six different risk factors: sensory perception, moisture, activity, mobility, nutrition, and friction and shear. A score of ≤18 is considered high risk. To date, research on the utility of the Braden Scale has focused on general medicine and nontrauma/burn surgery patients. We hypothesize that the Braden Scale does not accurately discriminate who will get a pressure ulcer among trauma and burn patients. METHODS: We collected data from medical records regarding documented Braden scores and presence of pressure ulcers regardless of staging. Patients with ulcers present on admission were excluded from analysis. For each patient, the lowest Braden score documented before the occurrence of the pressure ulcer was determined. A logistic regression was used to estimate odds ratios and associated 95% confidence intervals for the association between pressure ulcer likelihood and lowest Braden Scale measurement. To determine the discriminatory ability of the Braden Scale on pressure ulcer risk, four measures of performance (i.e., sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio) were calculated for four nonmutually exclusive groups: a Braden Scale measurement ≤18, ≤14, ≤12, and ≤9. RESULTS: From 2011 through 2014, a total of 2660 patients were admitted to the trauma/burn intensive care unit. Of these patients, 63 (2.3%) subsequently developed a pressure ulcer. A Braden Scale of ≤18 as the threshold for being at-risk of pressure ulcer had a sensitivity of 100% and specificity of 6%, whereas a Braden Scale of ≤9 had a sensitivity of 28.6% and a specificity of 90%. For all Braden Scale measurements, the positive likelihood ratio never reached the value of 10 that suggests high likelihood of an ulcer. CONCLUSIONS: The Braden scale has mediocre discriminatory ability among the trauma/burn population. In addition, the low positive likelihood ratio suggests that the Braden scale may not be a useful clinical tool as it may result in unnecessary expenditure of time and personnel resources in preventing pressure ulcer formation.

Early prediction of outcome after severe traumatic brain injury: a simple and practical model.

BACKGROUND: Traumatic brain injury (TBI) is a heterogeneous syndrome with a broad range of outcome. We developed a simple model for long-term outcome prognostication after severe TBI. METHODS: Secondary data analysis of a large multicenter randomized trial. Patients were grouped according to 6-month extended Glasgow outcome scale (eGOS): poor-outcome (eGOS ≤ 4; severe disability or death) and acceptable outcome (eGOS > 4; no or moderate disability). A prediction decision tree was built using binary recursive partitioning to predict poor or acceptable 6-month outcome. Comparison to two previously published and validated models was made. RESULTS: The decision tree included the predictors of head Abbreviated Injury Scale (AIS) severity, the Marshall computed tomography score, and pupillary reactivity. All patients with a head AIS severity of 5 were predicted to have a poor outcome. In patients with head AIS severity < 5, the model predicted an acceptable outcome for (1) those with Marshall score of 1, and (2) those with Marshall score above 1 but with reactive pupils at admission. The decision tree had a sensitivity of 72.3 % (95 % CI: 66.4-77.6 %) and specificity of 62.5 % (95 % CI: 54.9-69.6 %). The proportion correctly classified for the comparison models was similar to our model. Our model was more apt at correctly classifying those with poor outcome but more likely to misclassify those with acceptable outcome than the comparison models. CONCLUSION: Predicting long-term outcome early after TBI remains challenging and inexact. This model could be useful for research and quality improvement studies to provide an early assessment of injury severity, but is not sufficiently accurate to guide decision-making in the clinical setting.

Identification of Risk Factors for the Development of Pressure Ulcers Despite Standard Screening Methodology and Prophylaxis in Trauma Patients.

PURPOSE: To present information about a study of risk factors for development of pressure ulcers (PrUs) in trauma patients. TARGET AUDIENCE: This continuing education activity is intended for physicians and nurses with an interest in skin and wound care. OBJECTIVES/OUTCOMES: After participating in this educational activity, the participant should be better able to:1. Describe the previous PrU research, scope of the problem, and methodology of the study.2. Explain the results of the study identifying PrU risk factors for trauma patients. OBJECTIVE: Pressure ulceration prevention has been emphasized over the past several years in inpatient hospital settings with subsequent decreases in the development of pressure ulcers (PrUs). However, there remains a subset of trauma and burn patients that develop PrUs despite standard screening methodology and prophylaxis. This study determines the conditions that predict development of pressure ulcers (PrUs) despite conventional prophylaxis and screening. METHODS: Demographic and PrU data were collected over a 5-year period from June 2008 to May 2013. Patients diagnosed with PrUs upon arrival in the trauma bay were excluded from analysis. An ordinal logistic regression of PrU stage was used to estimate odds ratios (ORs) and associated 95% confidence intervals (CIs) for the association between characteristics of interest and odds of a PrU. A backward selection process was used to select the most parsimonious model. RESULTS: During the study period, 14,616 trauma patients were admitted and had available data. A total of 124 patients (0.85%) that met inclusion criteria went on to develop PrUs during their hospital course. Factors associated with the development of PrUs included spine Abbreviated Injury Scale (AIS) >3 (OR, 5.72; CI, 3.63-9.01), mechanical ventilation (OR, 1.95; CI, 1.23-3.10) and age 40 to 64 (OR, 2.09; CI, 1.24-3.52) and age ≥ 65 (OR, 4.48; CI, 2.52-7.95). Interestingly, head injury AIS >3 was protective from the development of PrUs (OR, 0.56; CI, 0.32-0.96). Hypotension and shock defined as systolic BP <90 mm Hg and base deficit less than -6 were not associated with the development of PrUs. In addition, body mass index was not associated with PrU development. CONCLUSIONS: Spinal injuries, older than age 40, and mechanical ventilation predict the development of PrUs for a subset of patients, despite conventional prophylaxis and screening. Advanced prevention methods, such as low-air-loss mattresses for these patient subgroups should be considered immediately upon identification of these risk factors during the hospital course.

Detailed description of all deaths in both the shock and traumatic brain injury hypertonic saline trials of the Resuscitation Outcomes Consortium.

OBJECTIVE: To identify causes and timing of mortality in trauma patients to determine targets for future studies. BACKGROUND: In trials conducted by the Resuscitation Outcomes Consortium in patients with traumatic hypovolemic shock (shock) or traumatic brain injury (TBI), hypertonic saline failed to improve survival. Selecting appropriate candidates is challenging. METHODS: Retrospective review of patients enrolled in multicenter, randomized trials performed from 2006 to 2009. Inclusion criteria were as follows: injured patients, age 15 years or more with hypovolemic shock [systolic blood pressure (SBP) ≤ 70 mm Hg or SBP 71-90 mm Hg with heart rate ≥ 108) or severe TBI [Glasgow Coma Score (GCS) ≤ 8]. Initial fluid administered was 250 mL of either 7.5% saline with 6% dextran 70, 7.5% saline or 0.9% saline. RESULTS: A total of 2061 subjects were enrolled (809 shock, 1252 TBI) and 571 (27.7%) died. Survivors were younger than nonsurvivors [30 (interquartile range 23) vs 42 (34)] and had a higher GCS, though similar hemodynamics. Most deaths occurred despite ongoing resuscitation. Forty-six percent of deaths in the TBI cohort were within 24 hours, compared with 82% in the shock cohort and 72% in the cohort with both shock and TBI. Median time to death was 29 hours in the TBI cohort, 2 hours in the shock cohort, and 4 hours in patients with both. Sepsis and multiple organ dysfunction accounted for 2% of deaths. CONCLUSIONS: Most deaths from trauma with shock or TBI occur within 24 hours from hypovolemic shock or TBI. Novel resuscitation strategies should focus on early deaths, though prevention may have a greater impact.

Transfusion of plasma, platelets, and red blood cells in a 1:1:1 vs a 1:1:2 ratio and mortality in patients with severe trauma: the PROPPR randomized clinical trial.

IMPORTANCE: Severely injured patients experiencing hemorrhagic shock often require massive transfusion. Earlier transfusion with higher blood product ratios (plasma, platelets, and red blood cells), defined as damage control resuscitation, has been associated with improved outcomes; however, there have been no large multicenter clinical trials. OBJECTIVE: To determine the effectiveness and safety of transfusing patients with severe trauma and major bleeding using plasma, platelets, and red blood cells in a 1:1:1 ratio compared with a 1:1:2 ratio. DESIGN, SETTING, AND PARTICIPANTS: Pragmatic, phase 3, multisite, randomized clinical trial of 680 severely injured patients who arrived at 1 of 12 level I trauma centers in North America directly from the scene and were predicted to require massive transfusion between August 2012 and December 2013. INTERVENTIONS: Blood product ratios of 1:1:1 (338 patients) vs 1:1:2 (342 patients) during active resuscitation in addition to all local standard-of-care interventions (uncontrolled). MAIN OUTCOMES AND MEASURES: Primary outcomes were 24-hour and 30-day all-cause mortality. Prespecified ancillary outcomes included time to hemostasis, blood product volumes transfused, complications, incidence of surgical procedures, and functional status. RESULTS: No significant differences were detected in mortality at 24 hours (12.7% in 1:1:1 group vs 17.0% in 1:1:2 group; difference, -4.2% [95% CI, -9.6% to 1.1%]; P = .12) or at 30 days (22.4% vs 26.1%, respectively; difference, -3.7% [95% CI, -10.2% to 2.7%]; P = .26). Exsanguination, which was the predominant cause of death within the first 24 hours, was significantly decreased in the 1:1:1 group (9.2% vs 14.6% in 1:1:2 group; difference, -5.4% [95% CI, -10.4% to -0.5%]; P = .03). More patients in the 1:1:1 group achieved hemostasis than in the 1:1:2 group (86% vs 78%, respectively; P = .006). Despite the 1:1:1 group receiving more plasma (median of 7 U vs 5 U, P < .001) and platelets (12 U vs 6 U, P < .001) and similar amounts of red blood cells (9 U) over the first 24 hours, no differences between the 2 groups were found for the 23 prespecified complications, including acute respiratory distress syndrome, multiple organ failure, venous thromboembolism, sepsis, and transfusion-related complications. CONCLUSIONS AND RELEVANCE: Among patients with severe trauma and major bleeding, early administration of plasma, platelets, and red blood cells in a 1:1:1 ratio compared with a 1:1:2 ratio did not result in significant differences in mortality at 24 hours or at 30 days. However, more patients in the 1:1:1 group achieved hemostasis and fewer experienced death due to exsanguination by 24 hours. Even though there was an increased use of plasma and platelets transfused in the 1:1:1 group, no other safety differences were identified between the 2 groups. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01545232.

Developing the Ready Military Medical Force: military-specific training in Graduate Medical Education.

Introduction: Graduate Medical Education plays a critical role in training the next generation of military physicians, ensuring they are ready to uphold the dual professional requirements inherent to being both a military officer and a military physician. This involves executing the operational duties as a commissioned leader while also providing exceptional medical care in austere environments and in harm's way. The purpose of this study is to review prior efforts at developing and implementing military unique curricula (MUC) in residency training programs. Methods: We performed a literature search in PubMed (MEDLINE), Embase, Web of Science, and the Defense Technical Information Center through August 8, 2023, including terms "graduate medical education" and "military." We included articles if they specifically addressed military curricula in residency with terms including "residency and operational" or "readiness training", "military program", or "military curriculum". Results: We identified 1455 articles based on title and abstract initially and fully reviewed 111. We determined that 64 articles met our inclusion criteria by describing the history or context of MUC, surveys supporting MUC, or military programs or curricula incorporated into residency training or military-specific residency programs. Conclusion: We found that although there have been multiple attempts at establishing MUC across training programs, it is difficult to create a uniform curriculum that can be implemented to train residents to a single standard across services and specialties.

Erythrocyte storage increases rates of NO and nitrite scavenging: implications for transfusion-related toxicity.

Storage of erythrocytes in blood banks is associated with biochemical and morphological changes to RBCs (red blood cells). It has been suggested that these changes have potential negative clinical effects characterized by inflammation and microcirculatory dysfunction which add to other transfusion-related toxicities. However, the mechanisms linking RBC storage and toxicity remain unclear. In the present study we tested the hypothesis that storage of leucodepleted RBCs results in cells that inhibit NO (nitric oxide) signalling more so than younger cells. Using competition kinetic analyses and protocols that minimized contributions from haemolysis or microparticles, our data indicate that the consumption rates of NO increased ~40-fold and NO-dependent vasodilation was inhibited 2-4-fold comparing 42-day-old with 0-day-old RBCs. These results are probably due to the formation of smaller RBCs with increased surface area: volume as a consequence of membrane loss during storage. The potential for older RBCs to affect NO formation via deoxygenated RBC-mediated nitrite reduction was also tested. RBC storage did not affect deoxygenated RBC-dependent stimulation of nitrite-induced vasodilation. However, stored RBCs did increase the rates of nitrite oxidation to nitrate in vitro. Significant loss of whole-blood nitrite was also observed in stable trauma patients after transfusion with 1 RBC unit, with the decrease in nitrite occurring after transfusion with RBCs stored for >25 days, but not with younger RBCs. Collectively, these data suggest that increased rates of reactions between intact RBCs and NO and nitrite may contribute to mechanisms that lead to storage-lesion-related transfusion risk.