Can Resuscitative Endovascular Balloon Occlusion of the Aorta Fly? Assessing Aortic Balloon Performance for Aeromedical Evacuation.

BACKGROUND: Noncompressible torso hemorrhage remains a leading cause of death. Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) placement may occur before transport; however, its efficacy has not been demonstrated at altitude. We hypothesized that changes in altitude would not result in blood pressure changes proximal to a deployed REBOA. METHODS: A simulation model for 7Fr guidewireless REBOA was used at altitudes up to 22,000 feet. Female pigs then underwent hemorrhagic shock to a mean arterial pressure (MAP) of 40 mm Hg. After hemorrhage, a REBOA catheter was deployed in the REBOA group and positioned but not inflated in the no-REBOA group. Animals underwent simulated aeromedical evacuation at 8000 ft or were left at ground level. After altitude exposure, the balloon was deflated, and the animals were observed. RESULTS: Taking the REBOA catheter to 22,000 ft in the simulation model resulted in a lower systolic blood pressure but a preserved MAP. In the porcine model, REBOA increased both systolic blood pressure and MAP compared with no-REBOA (P < 0.05) and was unaffected by altitude. No differences in postflight blood pressure, acidosis, or systemic inflammatory response were observed between ground and altitude REBOA groups. CONCLUSIONS: REBOA maintained MAP up to 22,000 feet in an inanimate model. In the porcine model, REBOA deployment improved MAP, and the balloon remained effective at altitude.

Utility of a tubularized extracellular matrix as an alternative conduit for arteriovenous fistula aneurysm repair.

OBJECTIVE: The treatment of segmental arteriovenous fistula aneurysms (AVFAs) remains a challenge in dialysis access preservation. We examined our experience with the use of tubularized extracellular matrix (ECM; CorMatrix, Roswell, Ga) for AVFA repair. METHODS: Between October 2013 and January 2015, we conducted a prospective study of CorMatrix ECM for AVFA repair. All patients underwent intraoperative fistulography. Patients with central venous stenosis or occlusion had simultaneous angioplasty and stenting as indicated. The aneurysm and overlying skin were then resected, and an ECM patch was fashioned into a tube for interposition repair. Patients with multiple AVFAs underwent staged repair. Cannulation of the repaired segments was allowed after 6 weeks. RESULTS: During the study period, 15 patients (40% male; mean age, 49.5 years) underwent 18 AVFA repairs using ECM (3 staged repairs). Six patients (40%) underwent simultaneous treatment of central vein lesions, whereas eight patients (53%) had associated skin erosion. Treated sites included radiocephalic (2), brachiobasilic (1), and brachiocephalic (15) AVFAs. All patients had hemodialysis at an alternative location on the same extremity without the need for catheter placement. Five patients underwent a follow-up ultrasound examination at a mean of 6 weeks. All studies demonstrated patency of the ECM segments without stenosis. At a mean follow-up time of 6.9 months, two thrombosis events were observed, both in patients with known refractory central venous stenosis treated with previous angioplasty (2) and stenting (1). Both patients required new access placement. No complications were attributable to ECM sites. CONCLUSIONS: ECM is an alternative conduit for salvage of an autologous AVFA. This technique may help avoid the use of prosthetic grafts and hemodialysis catheters. Patients with associated central venous stenosis are at risk of thrombosis.

Injury grade is a predictor of aortic-related death among patients with blunt thoracic aortic injury.

OBJECTIVE: The current Society for Vascular Surgery Clinical Practice Guidelines suggest urgent (<24 hours) thoracic endovascular aortic repair for grade (G) II to G IV blunt thoracic aortic injuries (BTAIs). The purpose of this study was to determine whether some patients may require more emergency treatment. METHODS: We reviewed imaging variables of prospectively collected BTAI patients between 1999 and 2014. We used computed tomographic angiography to classify BTAIs into four categories: G I, intimal tear; G II, intramural hematoma; G III, aortic pseudoaneurysm; and G IV, free rupture. Specific examination of G III injuries was undertaken in an effort to predict aortic-related mortality (ARM) before repair. For this subset, we examined pseudoaneurysm size, lesion/normal aortic diameter ratio, and mediastinal hematoma location and size. RESULTS: Among 331 patients with BTAIs, 86 died before imaging. Admission computed tomographic angiography was available for 205 patients (71.2% male; mean age, 39.3 years) with BTAIs (24 G I, 49 G II, 124 G III, 8 G IV). The mean Injury Severity Score was 35.6, and 22.4% had hypotension (<90 mm Hg). Overall mortality was 11.2% (G I/G II, 4.1%; G III/G IV, 15.3%; P = .02). ARM was 2.4% (G I/G II, 0%; G III/G IV, 3.8%; P = .09). ARM was significantly greater in G IV (3 of 8 [37.5%]) than G III (2 of 124 [1.6%]) vs G I/II (0 of 73 [0%]) injuries (P < .0001). Medical management alone was used in 53 (20 G I, 18 G II, 13 G III, and 2 G IV). Open repair was performed in 51 (3 G I, 9 G II, 36 G III, and 3 G IV) at a mean time to repair (TTR) of 10.6 hours. Thoracic endovascular aortic repair was conducted for 101 patients (1 G I, 22 G II, 75 G III, and 3 G IV) at a mean TTR of 9.4 hours. Median TTR for the overall population of BTAI patients was 24.0 hours from admission. (G I, 64.5 hours; G II, 24.0 hours; G III, 19.7 hours; and G IV, 3.5 hours). ARM occurred in four of five patients before planned repair (2 G III and 2 G IV), 7.0 ± 3.6 hours from admission. No G I/II ARM occurred. Among eight G IV injuries, there were three ARMs. Focus on G III injuries through regression analysis demonstrated that early clinical/imaging variables (eg, mediastinal hematoma dimensions and lesion/normal aortic diameter ratio) were not significant predictors of ARM. CONCLUSIONS: Injury grade is a predictor of ARM among patients with BTAIs. Aggressive use of the current Society for Vascular Surgery Clinical Practice Guidelines at a busy level I trauma center resulted in low rates of ARM. In this setting, identification of additional physiologic and radiographic criteria indicating the need for emergency (vs urgent) repair of aortic pseudoaneurysms remains elusive.

How to Stop the Bleed: First Care Provider Model for Developing Public Trauma Response Beyond Basic Hemorrhage Control.

INTRODUCTION: Since 2013, the First Care Provider (FCP) model has successfully educated the non-medical population on how to recognize life-threatening injuries and perform interventions recommended by the Committee for Tactical Emergency Casualty Care (C-TECC) and the Hartford Consensus in the disaster setting. Recent programs, such as the federal "Stop The Bleed" campaign, have placed the emphasis of public training on hemorrhage control. However, recent attacks demonstrate that access to wounded, recognition of injury, and rapid evacuation are equally as important as hemorrhage control in minimizing mortality. To date, no training programs have produced a validated study with regard to training a community population in these necessary principles of disaster response. METHODS: In our study, we created a reproducible community training model for implementation into prehospital systems. Two matched demographic groups were chosen and divided into "trained" and "untrained" groups. The trained group was taught the FCP curriculum, which the Department of Homeland Security recognizes as a Stop the Bleed program, while the untrained group received no instruction. Both groups then participated in a simulated mass casualty event, which required evaluation of multiple victims with varying degree of injury, particularly a patient with an arterial bleed and a patient with an airway obstruction. RESULTS: The objective measures in comparing the two groups were the time elapse until their first action was taken (T1A) and time to their solution of the simulation (TtS). We compared their times using one-sided t-test to demonstrate their responses were not due to chance alone. At the arterial bleed simulation, the T1A for the trained and untrained groups, respectively, were 34.75 seconds and 111 seconds (p-value = .1064), while the TtS were 3 minutes and 33 seconds in the trained group and eight minutes in the untrained groups (physiologic cutoff) (p-value = .0014). At the airway obstruction simulation, the T1A for the trained and untrained groups, respectively, were 20.5 seconds and 43 seconds (p-value = .1064), while the TtS were 32.6 seconds in the trained group and 7 minutes and 3 seconds in the untrained group (p-value = .0087). Simulation values for recently graduated nursing students and a local fire department engine company (emergency medical services [EMS]) were also given for reference. The trained group's results mirrored times of EMS. CONCLUSION: This study demonstrates an effective training model to civilian trauma response, while adhering to established recommendations. We offer our model as a potential solution for accomplishing the Stop The Bleed mission while advancing the potential of public disaster response.

Does platelet administration affect mortality in elderly head-injured patients taking antiplatelet medications?

A significant portion of patients sustaining traumatic brain injury (TBI) take antiplatelet medications (aspirin or clopidogrel), which have been associated with increased morbidity and mortality. In an attempt to alleviate the risk of increased bleeding, platelet transfusion has become standard practice in some institutions. This study was designed to determine if platelet transfusion reduces mortality in patients with TBI on antiplatelet medications. Databases from two Level I trauma centers were reviewed. Patients with TBI 50 years of age or older with documented preinjury use of clopidogrel or aspirin were included in our cohort. Patients who received platelet transfusions were compared with those who did not to assess outcome differences between them. Demographics and other patient characteristics abstracted included Injury Severity Score, Glasgow Coma Scale, hospital length of stay, and warfarin use. Three hundred twenty-eight patients comprised the study group. Of these patients, 166 received platelet transfusion and 162 patients did not. Patients who received platelets had a mortality rate of 17.5 per cent (29 of 166), whereas those who did not receive platelets had a mortality rate of 16.7 per cent (27 of 162) (P = 0.85). Transfusion of platelets in patients with TBI using antiplatelet therapy did not reduce mortality.

Multicenter retrospective study of noncompressible torso hemorrhage: Anatomic locations of bleeding and comparison of endovascular versus open approach.

BACKGROUND: Rational development of technology for rapid control of noncompressible torso hemorrhage (NCTH) requires detailed understanding of what is bleeding. Our objectives were to describe the anatomic location of truncal bleeding in patients presenting with NCTH and compare endovascular (ENDO) management versus open (OPEN) management. METHODS: This is a retrospective study of adult trauma patients with NCTH admitted to four urban Level I trauma centers in the Houston and San Antonio metropolitan areas in 2008 to 2012. Inclusion criteria include named axial torso vessel disruption, Abbreviated Injury Scale chest or abdomen score of 3 or higher with shock (base excess, <-4) or truncal operation in 90 minutes or less, or pelvic fracture with ring disruption. Exclusion criteria include isolated hip fractures, falls from standing, or prehospital cardiopulmonary resuscitation. After dichotomizing into OPEN, ENDO, and resuscitative thoracotomy (RT) groups based on the initial approach to control NCTH, a mixed-effects Poisson regression with robust error variance (controlling for age, mechanism, Injury Severity Score, shock, hypotension, and severe head injury as fixed effects and site as a random effect) was used to test the hypothesis that ENDO was associated with reduced in-hospital mortality in NCTH patients. RESULTS: Five hundred forty-three patients with NCTH underwent ENDO (n = 166, 31%), OPEN (n = 309, 57%), or RT (n = 68, 12%). Anatomic bleeding locations were 25% chest, 41% abdomen, and 31% pelvis. ENDO was used to treat relatively few types of vascular injuries, whereas OPEN and RT injuries were more diverse. ENDO patients had more blunt trauma (95% vs. 34% vs. 32%); severe injuries (median Injury Severity Score, 34 vs. 27 vs. 21), and increased time to intervention (median, 298 vs. 92 vs. 51 minutes) compared with OPEN and RT. Mortality was 15% versus 20% versus 79%. ENDO was associated with decreased mortality compared to OPEN (relative risk, 0.58; 95% confidence interval, 0.46-0.73). CONCLUSION: Although ENDO may reduce mortality in NCTH patients, significant group differences limit the generalizability of this finding. LEVEL OF EVIDENCE: Therapeutic, level V.

The Fog of War: Delirium Prevalence in a Combat Intensive Care Unit.

INTRODUCTION: Delirium is a fluctuating disturbance in consciousness associated with increased mortality. Injured warriors represent a unique unstudied population. We hypothesized delirium is common because of high injury severity scores and multidrug sedation regimens. METHODS: Mandatory delirium screening using the confusion assessment method (CAM) was initiated at Craig Joint Theater Hospital in Bagram, Afghanistan. Data were collected in July to August 2012 from the first 50 English-speaking trauma patients with CAM for the Intensive Care Unit (ICU) scores. RESULTS: Patients were male with mean age of 27.8 years; 88% of them were U.S. military personnel. Injury mechanisms were blast (68%) and gunshot (26%). Mean injury severity score was 20. Average ICU length of stay was 2.3 days; 64% were ventilated (for mean 1.2 days). Average time from arrival to CAM assessment was 7 hours, and 26 hours from the time of injury. Of patients, 44% were delirious, 36% at first CAM assessment. Fentanyl (62%) and ketamine (16%) were used for pain control (62%) and propofol for sedation (52%). There was no relationship between delirium and mechanism (p = 0.5) or ketamine on first ICU day (p = 0.2262). Delirium increased with vent days (p < .0001) and was associated with admission and mechanical ventilation (p = 0.0025). CONCLUSIONS: This study demonstrates a high rate of delirium in this unique population.

Contemporary outcomes of lower extremity vascular repairs extending below the knee: A multicenter retrospective study.

OBJECTIVES: To determine the outcomes of vascular injury interventions extending below the knee. METHODS: Vascular injury repairs extending below the knee from January 2008 to December 2014 were collected from six American College of Surgeons Level I trauma centers. Demographics, management, and outcomes were collected and analyzed. RESULTS: A total of 194 vascular injuries were identified. The mean age was 33.7 years, with 88.1% male, and 71.1% had blunt injury. Admission systolic blood pressure was less than 90 mm Hg in 10.8%; prehospital tourniquets were used in 5.6%. Median mangled extremity severity score (MESS) was 6.0 [interquartile range, 6]. Imaging used included computed tomography angiography (58.2%) and angiography (7.2%); with 66 (34.0%) proceeding directly to OR based on examination alone. Vascular interventions were conducted primarily by vascular (66.0%) and trauma (25.3%) surgeons at a median time from injury of 8 hours (interquartile range, 7 hours). Initial interventions included graft interposition (57.7%) with saphenous vein (111) or synthetic graft (1), primary repair (14.9%), endovascular stent-graft (1.5%), and patch angioplasty (2.1%). Fasciotomy was performed at initial operation in 41.8%, and for delayed compartment syndrome in 2.1%. Vascular reintervention was required in 20 patients (6.7%) for bleeding (seven patients) or thrombosis (13 patients). There was a higher reintervention rates for thrombosis among interposition grafts with distal anastomotic sites at the below-knee popliteal compared to those extending to the tibioperoneal trunk or distal trifurcation vessels, but this was not significant. (4/60, 6.7% vs. 6/49, 12.2%; p = 0.34). Postintervention amputation rates were significantly higher among interposition grafts extending distal to the popliteal (4/60 [6.7%] vs. 15/49 [30.6%]; p = 0.006). CONCLUSIONS: The management of vascular injuries extending below the knee remains a complex issue of extremity trauma care. The need for delayed amputation is significantly more common when revascularization below the distal popliteal artery is required. LEVEL OF EVIDENCE: Prognostic/epidemiologic study, level III; therapeutic/care management study, level IV.

The predictive value of multidetector CTA on outcomes in patients with below-the-knee vascular injury.

BACKGROUND: Multidetector computed tomographic angiography (MDCTA) has become the gold standard for the early assessment of lower extremity vascular injury. The objective of this study was to evaluate the predictive value of MDCTA documented vessel run-off to the foot on limb salvage rates after lower extremity vascular injury. METHODS: All trauma patients undergoing lower extremity MDCTA for suspected vascular injury assessed at 2 high-volume Level I trauma centers between January 2009 and December 2012. Demographics, clinical data and outcomes (compartment syndrome requiring fasciotomy and limb salvage) were extracted. The predictive value of MDCTA vessel run-off was tested against an aggregate gold standard of operative intervention, clinical follow-up and all imaging obtained. RESULTS: During the 4-year study period, 398 patients sustained lower extremity trauma and were screened for inclusion into this study. Of those, 166 (41.7%) patients (72.9% at MHH and 27.1% at LAC+USC Medical Center) underwent initial evaluation with MDCTA, 86 (51.8%) had vascular injury below the knee identified by MDCTA. Among these, the average age was 38.0±15.8 years, 80.2% were men and 83.7% sustained a blunt injury mechanism. On admission, 8.1% were hypotensive and the median ISS was 10 (range 1-57). There was a direct correlation between the number of patent vessels to the foot and the need for operative intervention (86.4% with no patent vessels, 56.0% with 1 patent vessel, 33.3% with 2 and 0.0% with 3, p<0.001). When outcomes were analysed, the rates of fasciotomy for compartment syndrome decreased in a stepwise fashion as the number of patent vessels to the foot increased (63.6% with no patent vessels; 44.0% with 1; 21.2% with 2; and 0.0% with 3; p=0.003). No amputations occurred in patients with 2 or more patent vessels to the foot (68.2% for no patent vessel; 16.0% for 1; 0.0% for 2; and 0.0% for 3; p<0.001). CONCLUSIONS: In this multicenter evaluation of patients undergoing MDCTA for suspected below-the-knee vascular injury, there was a stepwise increase in the need for operative intervention, fasciotomy and amputation as the number of patent vessels to the foot decreased.

Adherence to published antimicrobial prophylaxis guidelines for wounded service members in the ongoing conflicts in Southwest Asia.

In 2008, a clinical practice guideline (CPG) was developed for the prevention of infections among military personnel with combat-related injuries. Our analysis expands on a prior 6-month evaluation and assesses CPG adherence with respect to antimicrobial prophylaxis for U.S. combat casualties medically evacuated to Landstuhl Regional Medical Center over a 1-year period (June 2009 through May 2010), with an eventual goal of continuously monitoring CPG adherence and measuring outcomes as a function of compliance. We classified adherence to the CPG as receipt of recommended antimicrobials within 48 hours of injury. A total of 1106 military personnel eligible for CPG assessment were identified and 74% received antimicrobial prophylaxis. Overall, CPG compliance within 48 hours of injury was 75%. Lack of antimicrobial prophylaxis contributed 2 to 22% to noncompliance varying by injury category, whereas receipt of antibiotics other than preferred was 11 to 30%. For extremity injuries, antimicrobial prophylaxis adherence was 60 to 83%, whereas it was 80% for closed injuries and 68% for penetrating abdominal injuries. Overall, the results of our analysis suggest an ongoing need to improve adherence, monitor CPG compliance, and assess effectiveness.

Evaluation of military trauma system practices related to complications after injury.

BACKGROUND: The Joint Theater Trauma System (JTTS) was developed with the vision that every soldier, marine, sailor, and airman injured on the battlefield would have the optimal chance for survival and maximum potential for functional recovery. In this analysis, we hypothesized that injury and complication after injury surveillance information diffusion through the JTTS, via the dissemination of clinical practice guidelines and process improvements, would be associated with improved combat casualty clinical outcomes. METHODS: The current analysis was designed to profile different aspects of trauma system performance improvement, including monitoring of frequent posttraumatic complications, the assessment of an emerging complication trend, and measurement of the impact of the system interventions to identify potential practices for future performance improvement. Data captured from the Joint Theater Trauma Registry on patients admitted to military medical treatment facilities as a result of wounds incurred in Iraq and Afghanistan from 2003 to 2010 were retrospectively analyzed to determine the potential impact of complication surveillance and process improvement initiatives on clinical practice. RESULTS: Developed metrics demonstrated that the surveillance capacity and evidence-based quality improvement initiatives disseminated through the JTTS were associated with improved identification and mitigation of complications following battlefield injury. CONCLUSION: The Joint Trauma System enables evidence-based practice across the continuum of military trauma care. Concurrent data collection and performance improvement activities at the local and system level facilitate timely clinical intervention on identified trauma complications and the subsequent measurement of the effectiveness of those interventions. LEVEL OF EVIDENCE: Epidemiologic study, level III.

Early treatment of blunt cerebrovascular injury with concomitant hemorrhagic neurologic injury is safe and effective.

BACKGROUND: Early pharmacologic treatment for blunt cerebrovascular injury (BCVI) is often withheld when concomitant traumatic brain injury or cervical spinal cord injury occurs. This study examines the safety and efficacy of early treatment for patients with both BCVI and traumatic neurologic injury (TNI). METHODS: Ten-year retrospective review of patients with BCVI and a TNI was performed. Stroke outcomes for those treated with pharmacologic therapy for their BCVI were compared with those not treated. In addition, the likelihood of worsening of TNI was determined for those exposed to pharmacologic therapy compared with those not exposed. Multivariate logistic regression techniques were used to analyze adjusted odds ratio for stroke risk. RESULTS: Seventy-seven patients were identified with BCVI + TNI. Strokes occurred in 27% patients with 3 of 21 (14%) strokes present at arrival. There were no differences in baseline characteristics between groups. Stroke rate was higher in the untreated group compared with treated (57% vs. 4%, p < 0.0001). On multivariate regression, treatment status was the most significant stroke predictor (adjusted odds ratio 4.4, 3.0-6.5, p < 0.0001, c-stat 0.93). There was no difference in risk of hemorrhagic deterioration of traumatic brain injury based on pharmacologic exposure versus no exposure (5% vs. 6%, p = 0.6). Likewise, no patient with spinal cord injury worsened as a result of pharmacologic exposure. Of the potentially preventable strokes, 24% (4 of 17) resulted in a stroke-related death and all four deaths occurred in the untreated group. CONCLUSION: The benefit of early treatment for BCVI markedly outweighs the risk of treatment for patients suffering concomitant BCVI and hemorrhagic neurologic injury. LEVEL OF EVIDENCE: : III.

The impact of preinjury antiplatelet and anticoagulant pharmacotherapy on outcomes in elderly patients with hemorrhagic brain injury.

BACKGROUND: More elderly trauma patients are identified with preinjury use of clopidogrel, aspirin, or warfarin (CAW). The purpose of this study was to determine whether preinjury CAW use was an important predictor of mortality in patients aged >or=50 years with blunt, hemorrhagic brain injury (HBI). METHODS: A retrospective review of patients with blunt, HBI aged >or=50 years with subgroup analysis for older (>70 years) and younger (50-70 years) patients was performed. CAW use was analyzed for differences in age, gender, hospital length of stay (LOS), Injury Severity Score (ISS), Glasgow Coma Score (GCS), mechanism of injury (MOI), platelet transfusion therapy (PLT), disposition at discharge, and in-hospital mortality. RESULTS: From January 2003 to October 2005, 416 patients were identified. The mean age was 69+/-1 years. No differences were found for ISS (24 +/- 0.5), GCS (12 +/- 0.2), or LOS (8 +/- 0.4 days). CAW use was present in 40% of patients and significantly higher in older patients. Mortality was not different between older and younger CAW(+) patients, but it significantly increased for older CAW(-) patients. Significant predictors of death included age, ISS, and GCS (P<.02). CONCLUSIONS: Preinjury CAW use in older blunt, HBI patients is not associated with increased mortality. Age was a significant predictor of mortality independent of CAW use.