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INTRODUCTION Previously, in a murine model of blunt thoracic trauma, we provided evidence of primary pulmonary thrombosis associated with increased expression of the cell adhesion molecule, P-selectin. In this study, mice are treated with P-selectin blocking antibody after injury to investigate the clinical viability of this antibody for the prevention of pulmonary thrombosis. In addition, viscoelastic testing is performed to investigate if P-selectin inhibition has a detrimental impact on normal hemostasis. METHODS A murine model of thoracic trauma was used. Mice were divided into sham control and experimental injury groups. Thirty minutes after trauma, mice were treated with the following: P-selectin blocking antibody, isotype control antibody, low-dose heparin, high-dose heparin, or normal saline. At 90 minutes, whole blood was collected for characterization of coagulation by viscoelastic coagulation monitor (VCM Vet; Entegrion, Durham, NC). Mean clotting time, clot formation time, clot kinetics (α angle), and maximum clot firmness were compared between each treatment group. RESULTS Mice that received P-selectin antibody 30 minutes after blunt thoracic trauma had four- to fivefold less (p < 0.001) arterial fibrin accumulation than those that received the isotype control. In both sham and trauma groups, compared with vehicle (normal saline) alone, no statistical difference was noted in any coagulation parameters after injection with P-selectin antibody, isotype control, or low-dose heparin. In addition, blinded histopathological evaluation yielded no difference in hemorrhage scores between injured mice treated with P-selectin blocking antibody and those treated with isotype antibody control. CONCLUSION This study supports the clinical use of P-selectin blocking antibody for the prevention of pulmonary thrombosis by confirming its efficacy when given after a blunt thoracic trauma. In addition, we demonstrated that the administration of P-selectin antibody does not adversely affect systemic coagulation as measured by viscoelastic testing, suggesting that P-selectin antibody can be safely given during the acute posttraumatic period.

The Military Health System is currently in the midst of a sea change as Military Treatment Facilities transition to Defense Health Agency governance. During this time of transition, the measurement and sustainment of forward deployed caregiver readiness is undergoing appropriate and much needed scrutiny. Recently, the American Association for the Surgery of Trauma assembled an expert panel to examine forward deployed caregiver readiness, identify gaps, and propose potential solutions. A qualitative theme array analysis of the session was performed, and three readiness themes were identified including: 1) defining readiness, 2) measuring readiness, and 3) maintaining and replenishing readiness. This article focuses on the various readiness gaps, solutions and areas of controversy identified. Level of evidence Expert opinion, level V.

Abdominal vascular trauma accounts for a small percentage of military and a moderate percentage of civilian trauma, affecting all age ranges and impacting young adult men most frequently. Penetrating causes are more frequent than blunt in adults, while blunt mechanisms are more common among pediatric populations. High rates of associated injuries, bleeding, and hemorrhagic shock ensure that, despite advances in both diagnostic and therapeutic technologies, immediate open surgical repair remains the mainstay of treatment for traumatic abdominal vascular injuries. Because of their devastating nature, abdominal vascular injuries remain a significant source of morbidity and mortality among trauma patients. The American Association for the Surgery of Trauma in conjunction with the World Society of Emergency Surgery seek to summarize the literature to date and provide guidelines on the presentation, diagnosis, and treatment of abdominal vascular injuries. LEVEL OF EVIDENCE: Review study, level IV.

Background Thromboembolic events within the pulmonary arterial vasculature are a troublesome complication of severe blunt thoracic trauma. Mechanisms underlying these events are currently in question as pulmonary thromboembolic events in this particular trauma population tend to be diagnosed more rapidly, more frequently and without an associated systemic thrombosis. This study investigates the role of P-selectin in thrombus formation through the use of in vivo blocking antibodies. We hypothesize that P-selectin plays a pivotal role in de novo pulmonary arterial thrombosis following blunt thoracic trauma. Methods A murine weight-drop model of lateral blunt thoracic trauma was used. Wild-type mice in the experimental group were given blocking antibodies against P-selectin prior to the trauma. All mice were euthanized at 24 hours for evaluation with hematoxylin-eosin staining or immunofluorescent staining for fibrin and P-selectin. Results Injured mice that did not receive the P-selectin antibody showed a robust fourfold to fivefold increase in fibrin accumulation in both coup and contrecoup tissues (fluorescence per um of arterial wall) compared to uninjured sham mice. In contrast, mice pretreated with P-selectin blocking antibody showed no significant increase in fibrin accumulation on either side of the lungs after blunt thoracic trauma. No difference in mean fibrin deposition was found between sham controls that received the P-selectin-blocking antibody and those that received an isotype control antibody. Conclusion P-selectin expression increases at the pulmonary arterial luminal surface following blunt thoracic trauma. In addition, P-selectin-blocking in vivo prevents pulmonary arterial fibrin accumulation after blunt thoracic trauma, confirming that P-selectin is necessary for de novo pulmonary arterial thrombosis after traumatic injury.

The US Military has achieved the highest casualty survival rates in its history. However, there remain multiple areas in combat trauma that present challenges to the delivery of high-quality and effective trauma care. Previous work has identified research priorities for pre-hospital care, but there has been no similar analysis for forward surgical care.A list of critical "focus areas" was developed by the Committee on Surgical Combat Casualty Care (CoSCCC). Individual topics were solicited and mapped to appropriate focus areas by group consensus and review of Eastern Association for the Surgery of Trauma (EAST) and Joint Trauma System guidelines. A web-based survey was distributed to the CoSCCC and the military committees of EAST and the American Association for the Surgery of Trauma. Topics were rated on a Likert scale from 1 (low) to 10 (high priority). Descriptives, univariate statistics, and inter-rater correlation analysis was performed.13 research focus areas were identified (eight clinical and five adjunctive categories). Ninety individual topics were solicited. The survey received 64 responses. The majority of respondents were military (90%) versus civilians (10%). There was moderate to high agreement (inter-rater correlation coefficient = 0.93, p0.01) for 10 focus areas. The top five focus areas were Personnel/Staffing (mean, 8.03), Resuscitation and Hemorrhage Management (7.49), Pain/Sedation/Anxiety Management (6.96), Operative Interventions (6.9), and Initial Evaluation (6.9). The "Top 10" research priorities included four in Personnel/Staffing, four in Resuscitation/Hemorrhage Management, and three in Operative Interventions. A complete list of the topics/scores will be presented.This is the first objective ranking of research priorities for combat trauma care. The "Top 10" priorities were all from three focus areas, supporting prioritization of personnel/staffing of austere teams, resuscitation/hemorrhage control, and damage-control interventions. This data will help guide Department of Defense research programs and new areas for prioritized funding of both military and civilian researchers.Study design, level IV.

Screening for blunt cerebrovascular injuries (BCVIs) in asymptomatic high-risk patients has become routine. To date, the length of this asymptomatic period has not been defined. Determining the time to stroke could impact therapy including earlier initiation of antithrombotics in multiply injured patients. The purpose of this study was to determine the time to stroke in patients with a BCVI-related stroke. We hypothesized that the majority of patients suffer stroke between 24 hours and 72 hours after injury.Patients with a BCVI-related stroke from January 2007 to January 2017 from 37 trauma centers were reviewed.During the 10-year study, 492 patients had a BCVI-related stroke; the majority were men (61%), with a median age of 39 years and ISS of 29. Stroke was present at admission in 182 patients (37%) and occurred during an Interventional Radiology procedure in six patients. In the remaining 304 patients, stroke was identified a median of 48 hours after admission: 53 hours in the 144 patients identified by neurologic symptoms and 42 hours in the 160 patients without a neurologic examination and an incidental stroke identified on imaging. Of those patients with neurologic symptoms, 88 (61%) had a stroke within 72 hours, whereas 56 had a stroke after 72 hours; there was a sequential decline in stroke occurrence over the first week. Of the 304 patients who had a stroke after admission, 64 patients (22%) were being treated with antithrombotics when the stroke occurred.The majority of patients suffer BCVI-related stroke in the first 72 hours after injury. Time to stroke can help inform clinicians about initiation of treatment in the multiply injured patient.Prognostic/Epidemiologic, level III.

Introduction Pancreatic trauma results in high morbidity and mortality, in part caused by the delay in diagnosis and subsequent organ dysfunction. Optimal operative management strategies remain unclear. We therefore sought to determine CT accuracy in diagnosing pancreatic injury and the morbidity and mortality associated with varying operative strategies. Methods We created a multicenter, pancreatic trauma registry from 18 Level 1 and 2 trauma centers. Adult, blunt or penetrating injured patients from 2005 to 2012 were analyzed. Sensitivity and specificity of CT scan identification of main pancreatic duct injury was calculated against operative findings. Independent predictors for mortality, adult respiratory distress syndrome (ARDS), and pancreatic fistula and/or pseudocyst were identified through multivariate regression analysis. The association between outcomes and operative management was measured. Results We identified 704 pancreatic injury patients of whom 584 (83%) underwent a pancreas-related procedure. CT grade modestly correlated with OR grade (r 0.39) missing 10 ductal injuries (9 grade III, 1 grade IV) providing 78.7% sensitivity and 61.6% specificity. Independent predictors of mortality were age, Injury Severity Score (ISS), lactate, and number of packed red blood cells transfused. Independent predictors of ARDS were ISS, Glasgow Coma Scale score, and pancreatic fistula (OR 5.2, 2.6-10.1). Among grade III injuries (n = 158, 22.4%), the risk of pancreatic fistula/pseudocyst was reduced when the end of the pancreas was stapled (OR 0.21, 95% CI 0.05-0.9) compared with sewn and was not affected by duct stitch placement. Drainage alone in grades IV (n = 25) and V (n = 24) injuries carried increased risk of pancreatic fistula/pseudocyst (OR 8.3, 95% CI 2.2-32.9). Conclusion CT is insufficiently sensitive to reliably identify pancreatic duct injury. Patients with grade III injuries should have their resection site stapled instead of sewn and a duct stitch is unnecessary. Further study is needed to determine if drainage alone should be employed in grades IV and V injuries. Level of evidence Epidemiologic/Diagnostic study, level III.

BACKGROUNDDespite clinical reports of poor outcomes, the degree to which resuscitative endovascular balloon occlusion of the aorta (REBOA) exacerbates traumatic brain injury (TBI) is not known. We hypothesized that combined effects of increased proximal mean arterial pressure (pMAP), carotid blood f

BACKGROUND Combat-injured patients may require rapid and sustained support during transport; however, the prolonged aortic occlusion produced by conventional resuscitative endovascular balloon occlusion of the aorta (REBOA) may lead to substantial morbidity. Partial REBOA (P-REBOA) may permit longer periods of occlusion by allowing some degree of distal perfusion. However, the ability of this procedure to limit exsanguination is unclear. We evaluated the impact of P-REBOA on immediate survival and ongoing hemorrhage in a highly lethal swine liver injury model. METHODS Fifteen Yorkshire-cross swine were anesthetized, instrumented, splenectomized, and subjected to rapid 10% total blood loss followed by 30% liver amputation. Coagulopathy was created through colloid hemodilution. Randomized swine received no intervention (control), P-REBOA, or complete REBOA (C-REBOA). Central mean arterial pressure (cMAP), carotid blood flow, and blood loss were recorded. Balloons remained inflated in the P-REBOA and C-REBOA groups for 90 minutes followed by graded deflation. The study ended at 180 minutes from onset of hemorrhage or death of the animal. Survival analysis was performed, and data were analyzed using repeated-measures analysis of variance with post hoc pairwise comparisons. RESULTS Mean survival times in the control, P-REBOA, and C-REBOA groups were, 25 ± 21, 86 ± 40, and 163 ± 20 minutes, respectively (p < 0.001). Blood loss was greater in the P-REBOA group than the C-REBOA or control groups, but this difference was not significant (4,722 ± 224, 3,834 ± 319, 3,818 ± 37 mL, respectively, p = 0.10). P-REBOA resulted in maintenance of near-baseline carotid blood flow and cMAP, while C-REBOA generated extreme cMAP and prolonged supraphysiologic carotid blood flow. Both experimental groups experienced profound decreases in cMAP following balloon deflation. CONCLUSION In the setting of severe ongoing hemorrhage, P-REBOA increased survival time beyond the golden hour while maintaining cMAP and carotid flow at physiologic levels.

Background Although thoracic trauma is common, little is known about which factors lead to poor functional outcomes. We sought to determine which characteristics of chest wall injury predict postrecovery pulmonary symptoms or health-related quality of life. Methods We conducted a secondary analysis of data from a randomized trial involving patients with chest wall injuries at a Level I trauma center between December 2007 and July 2012. We evaluated the overall severity of the chest wall injury-characterized primarily by the number of fractured ribs-and rib fracture location (upper, middle, and lower; anterior, lateral, and posterior) as predictors of patient-reported outcomes 60 days after injury: dyspnea burden (0-40), Modified Medical Research Council Dyspnea Scale (MMRC) (0-4), St. George's Respiratory Questionnaire (SGRQ), and normalized Medical Outcomes Study Short-Form 36 (SF-36) scores. Results Of 189 evaluable subjects, the mean (SD) number of fractured ribs was 5 (4). The number of fractured ribs was not associated with dyspnea burden, MMRC, or SGRQ scores. After adjustment for confounders, each additional fractured rib was associated with worse SF-36 Physical Functioning and Bodily Pain scores (-0.6 units [95% confidence interval (CI), -1.1 to 0.0] and -0.8 units [95% CI, -1.3 to -0.2], respectively). Lower rib fractures were associated with worse dyspnea burden (3.4 units; 95% CI, 1.0-5.9), MMRC score (0.4 units; 95% CI, 0.0-0.8), and SF-36 Physical Functioning, Role-Physical, Role-Emotional, and Physical Component Summary scores (-4 units [95% CI, -8 to 0], -5 units [95% CI, -8 to -1], -4 units [95% CI, -8 to 0], and -4 units [95% CI, -7 to -1], respectively). Conclusion The overall anatomic severity of chest wall injuries does not predict worse dyspnea symptoms 60 days after injury, but it does predict increased patient perceptions of pain and physical function limitations. Lower rib fractures predict both persistent respiratory symptoms and perception of decreased overall health. Level of evidence Prognostic/epidemiologic study, level III.

As North Atlantic Treaty Organization (NATO) countries begin troop withdrawal from Afghanistan, military medicine needs programs for combat surgeons to retain the required knowledge and surgical skills. Each military branch runs programs at various Level I academic trauma centers to deliver predeployment training and provide a robust trauma experience for deploying surgeons. Outside of these successful programs, there is no system-wide mechanism for nondeploying military surgeons to care for a high volume of critically ill trauma patients on a regular basis in an educational environment that promotes continued professional development. We hypothesize that fully integrated military-civilian relationship regional Level I trauma centers provide a surgical experience more closely mirroring that seen in a Role III hospital than local Level II and Level III trauma center or medical treatment facilities.We characterized the Level I trauma center practice using the number of trauma resuscitations, operative trauma/acute care surgery procedures, number of work shifts, operative density (defined as the ratio of operative procedures/days worked), and frequency of educational conferences. The same parameters were collected from two NATO Role III hospitals in Afghanistan during the peak of Operation Enduring Freedom. Data for two civilian Level II trauma centers, two civilian Level III trauma centers, and a Continental United States Military Treatment Facility without trauma designation were collected.The number of trauma resuscitations, number of 24-hour shifts, operative density, and educational conferences are shown in the table for the Level I trauma center compared with the different institutions. Civilian center trauma resuscitations and operative density were highest at the Level I trauma center and were only slightly lower than what was seen in Afghanistan. Level II and III trauma centers had lower numbers for both. The Level I trauma center provided the most frequent educational opportunities.In a Level I academic trauma center integrated program, military and civilian surgeons have the same clinical and educational responsibilities: rounding and operating, managing critical care patients, covering trauma/acute care surgery call, and mentoring surgery residents in an integrated residency program. The Level I trauma center experience most closely mimics the combat surgeon experience seen at NATO Role III hospitals in Afghanistan compared with other civilian trauma centers. At high-volume Level I trauma centers, military surgeons will have a comprehensive trauma practice, including dedicated educational opportunities. We recommend integrated programs with Level I academic trauma centers as the primary mechanism for sustaining military combat surgical skills in the future.