The Efficacy of Whole Blood Resuscitation During Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) to Mitigate Post-occlusion Circulatory Collapse: A Translational Model in Large Swine.

INTRODUCTION: Uncontrolled torso hemorrhage is the primary cause of potentially survivable deaths on the battlefield. Zone 1 Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA), in conjunction with damage control resuscitation, may be an effective management strategy for these patients in the prehospital or austere phase of their care. However, the effect of whole blood (WB) transfusion during REBOA on post-occlusion circulatory collapse is not fully understood. MATERIALS AND METHODS: Yorkshire male swine (n = 6 per group, 70-90 kg) underwent a 40% volume-controlled hemorrhage. After a 10-minute hemorrhagic shock period, a REBOA balloon was inflated in Zone 1. Fifteen minutes after inflation, 0, 1, or 3 units (450 mL/unit) of autologous WB was infused through the left jugular vein. Thirty minutes after initial balloon inflation, the balloon was deflated slowly over 3 minutes. Following deflation, normal saline was administered (up to 3,000 mL) and swine were observed for 2 hours. Survival (primary outcome), hemodynamics, and blood gas values were compared among groups. Statistical significance was determined by log-rank test, one-way ANOVA, and repeated measures ANOVA. RESULTS: Survival rates were comparable between groups (P = .345) with 66% of control, 33% of the one-unit animals, and 50% of the 3-unit animals survived until the end of the study. Following WB infusion, both the 1-unit and the 3-unit groups had significantly higher blood pressure (P < .01), pulmonary artery pressure (P < .01), and carotid artery flow (P < .01) compared to the control group. CONCLUSIONS: WB transfusion during Zone 1 REBOA was not associated with increased short-term survival in this large animal model of severe hemorrhage. We observed no signal that WB transfusion may mitigate post-occlusion circulatory collapse. However, there was evidence of supra-normal blood pressures during WB transfusion.

Associations with Prehospital Antibiotic Receipt among Combat Casualties with Open Wounds: A Department of Defense Trauma Registry Study.

INTRODUCTION: Current Tactical Combat Casualty Care (TCCC) guidelines recommend antibiotic administration for all open wounds to prevent infection. We identified associations between demographics, procedures, and medicines with the receipt of prehospital antibiotics among combat casualties. MATERIALS AND METHODS: We used a series of emergency department procedure codes to identify adult subjects within the Department of Defense Trauma Registry from January 2007 to August 2016 who sustained open wounds. We compared demographics, procedures, and medicines administered among casualties receiving prehospital wound prophylaxis versus casualties not receiving antibiotic prophylaxis. We controlled for confounders with multivariable logistical regression. RESULTS: We identified 18,366 encounters meeting inclusion criteria. Antibiotic recipients (n = 2384) were comparable to nonrecipients (n = 15,982) with regard to age and sex. Antibiotic recipients were more likely to sustain injuries from firearms and undergo all procedures examined related to hemorrhage control, airway management, pneumothorax treatment, and volume replacement except for intraosseous access. Antibiotic recipients were less likely to sustain injuries from explosives. Antibiotic recipients had a modestly higher survival than nonrecipients (97.4% versus 96.0%). Associations with prehospital antibiotic receipt in multivariable logistic regression included non-North Atlantic Treaty Organization military force affiliation (odds ratio (OR) 4.65, 95% CI, 1.0-20.8), tachycardia (OR 3.4, 95% CI, 1.1-10.5), intubation (OR 2.0, 95% CI, 1.1-3.8), and administration of tranexamic acid (OR 5.6, 95% CI, 1.2-26.5). CONCLUSIONS: The proportion of combat casualties with open wounds receiving prehospital antibiotics was low despite published recommendations for early antibiotics in patients with open wounds. These findings highlight the ongoing need for additional educational and quality assurance initiatives to continue improving adherence to TCCC guidelines with regard to prehospital antibiotic administration. Future studies are necessary to determine reasons for suboptimal TCCC guideline compliance.

Patterns of Palliation: A Review of Casualties That Received Pain Management Before Reaching Role 2 in Afghanistan.

INTRODUCTION: Battlefield pain management changed markedly during the first 20 years of the Global War on Terror. Morphine, long the mainstay of combat analgesia, diminished in favor of fentanyl and ketamine for military pain control, but the options are not hemodynamically or psychologically equivalent. Understanding patterns of prehospital analgesia may reveal further opportunities for combat casualty care improvement. MATERIALS AND METHODS: Using Department of Defense Trauma Registry data for the Afghanistan conflict from 2005 to 2018, we examined 2,402 records of prehospital analgesia administration to assess temporal trends in medication choice and proportions receiving analgesia, including subanalysis of a cohort screened for an indication with minimal contraindication for analgesia. We further employed frequency matching to explore the presence of disparities in analgesia by casualty affiliation. RESULTS: Proportions of documented analgesia increased throughout the study period, from 0% in 2005 to 70.6% in 2018. Afghan casualties had the highest proportion of documented analgesia (53.0%), versus U.S. military (31.9%), civilian/other (23.3%), and non-U.S. military (19.3%). Fentanyl surpassed morphine in the frequency of administration in 2012. The median age of those receiving ketamine was higher (30 years) than those receiving fentanyl (26 years) or nonsteroidal anti-inflammatory drugs (23 years). Among the frequency-matched subanalysis, the odds ratio for ketamine administration with Afghan casualties was 1.84 (95% CI, 1.30-2.61). CONCLUSIONS: We observed heterogeneity of prehospital patient care across patient affiliation groups, suggesting possible opportunities for improvement toward an overall best practice system. General increase in documented prehospital pain management likely reflects efforts toward complete documentation, as well as improved options for analgesia. Current combat casualty care documentation does not include any standardized pain scale.

Development and Evaluation of An Abbreviated Extracorporeal Membrane Oxygenation (ECMO) Course for Nonsurgical Physicians and Nurses.

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) is a modification of cardiopulmonary bypass that allows prolonged support of patients with severe respiratory or cardiac failure. ECMO indications arse rapidly evolving and there is growing interest in its use for cardiac arrest and cardiogenic shock. However, ECMO training programs are limited. Training of emergency medicine and critical care clinicians could expand the use of this lifesaving intervention. Our objective was to develop and evaluate an abbreviated ECMO course that can be taught to emergency and critical care physicians and nurses. METHODS: We developed a training model using Yorkshire swine (Sus scrofa), a procedure instruction checklist, a confidence assessment, and a knowledge assessment. Participants were assigned to teams of one emergency medicine or critical care physician and one nurse and completed an abbreviated 8-hour ECMO course. An ECMO specialist trained participants on preparation of the ECMO circuit and oversaw vascular access and ECMO initiation. We used the instruction checklist to evaluate performance. Participants completed confidence and knowledge assessments before and after the course. RESULTS: Seventeen teams (34 clinicians) completed the abbreviated ECMO course. None had previously completed an ECMO certification course. Immediately following the course, all teams successfully primed and prepared the ECMO circuit. Fifteen teams (88%, 95% confidence interval [CI] = 64% to 99%) successfully initiated ECMO. Participants improved their knowledge (difference 21.2, 95% CI = 16.5 to 25.8) and confidence (difference 40.3, 95% CI = 35.6 to 45.0) scores after completing the course. CONCLUSIONS: We developed an accelerated 1-day ECMO course. Clinicians' confidence and knowledge assessments improved and 88% of teams could successfully initiate venoarterial ECMO after the course.