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.

The 16-year evolution of a military-civilian partnership: The University of Alabama at Birmingham experience.

BACKGROUND: At the University of Alabama at Birmingham (UAB), a multi-tiered military-civilian partnership (MCP) has evolved since 2006. We aimed to outline this model to facilitate potential replication nationally. METHODS: We performed a comprehensive review of the partnership between UAB, the United States Air Force Special Operations Command, and the Department of Defense (DoD) reviewing key documents and conducting interviews with providers. As a purely descriptive study, this project did not involve any patient data acquisition or analysis and therefore was exempt from institutional review board approval per institutional policy. RESULTS: At the time of this review, six core programs existed targeting training, clinical proficiency, and research. Training: (1) The Special Operations Center for Medical Integration and Development trains up to 144 combat medics yearly. (2) UAB trains one integrated military Surgery resident yearly with two additional civilian-sponsored military residents in Emergency Medicine. (3) UAB's Surgical Critical Care Fellowship had one National Guard member with two incoming Active-Duty, one Reservist and one prior service member in August 2022. Clinical Proficiency: (4) UAB hosts four permanently assigned United States Air Force Special Operations Command Special Operations Surgical Teams composed of general surgeons, anesthesiologists, certified registered nurse anesthetists, surgical technologists, emergency physicians, critical care registered nurses, and respiratory therapists totaling 24 permanently assigned active-duty health care professionals. (5) In addition, two fellowship-trained Air Force Trauma Critical Care Surgeons, one Active-Duty and one Reservist, are permanently assigned to UAB. These clinicians participate fully and independently in the routine care of patients alongside their civilian counterparts. Research: (6) UAB's Division of Trauma and Acute Care Surgery is currently conducting nine DoD-funded research projects totaling $6,482,790, and four research projects with military relevance funded by other agencies totaling $15,357,191. CONCLUSION: The collaboration between UAB and various elements within the DoD illustrates a comprehensive approach to MCP. Replicating appropriate components of this model nationally may aid in the development of a truly integrated trauma system best prepared for the challenges of the future. LEVEL OF EVIDENCE: Economic and Value-based Evaluations; Level IV.

Military Medical Role in Civilian Disaster.

US military medical units have responded to natural disasters (eg, hurricanes, earthquakes), relieved overwhelmed civilian health care systems (eg, during the COVID-19 pandemic), and provided support to stabilization efforts after civil unrest. The military will continue to assist civilian agencies with future medical response to similar disasters, contagious outbreaks, or even terrorist attacks. The keys to an effective disaster response are unity of effort, prior coordination, and iterative practice during military-civilian exercises to identify strengths and areas of improvement. Critical care advanced practice nurses are likely to work concurrently with military medical colleagues in multiple scenarios in the future; therefore, it is important for these nurses to understand the capacities and limitations of military medical assets. This article describes the capabilities and collaboration needed between civilian and military medical assets during a variety of disaster scenarios.

Universal screening for blunt cerebrovascular injury.

BACKGROUND: Blunt cerebrovascular injury (BCVI) can result in thromboembolic stroke. Many trauma centers selectively screen patients with cervical computed tomographic angiography (CTA) based on clinical criteria. In 2016, our institution adopted universal screening for BCVI for all blunt trauma patients. The aim of this study was to accurately determine the incidence of BCVI and to evaluate the diagnostic performance of the Denver criteria (DC), expanded Denver criteria (eDC), and Memphis criteria (MC) in selecting patients for screening. METHODS: Retrospective cohort study of adult (≥16 years) blunt trauma patients who presented to the Level I trauma center at University of Alabama at Birmingham. We reviewed all CTA reports and selected CTA images to obtain the true incidence rate of BCVI. We then evaluated the diagnostic performance of the DC, eDC, and MC. RESULTS: A total of 6,800 patients who had suffered blunt trauma were evaluated, of whom 6,287 (92.5%) had a neck CTA. Of these, 480 (7.6%) patients had CTA evidence of BCVI. The eDC identified the most BCVI cases (sensitivity 74.7%) but had the lowest positive predictive value (14.6%). The DC and MC had slightly greater positive predictive values (19.6% and 20.6%, respectively) and had the highest diagnostic ability in terms of likelihood ratio (2.8 and 2.9) but had low sensitivity (57.5% and 47.3%). Consequently, if relying on the traditional screening criteria, the DC, eDC, and MC would have respectively resulted in 42.5%, 25.3%, and 52.7% of patients with BCVI identified by universal screening not receiving a neck CTA to screen for BCVI. CONCLUSION: Blunt cerebrovascular injury is even more common than previously thought. The diagnostic performance of selective clinical screening criteria is poor. Consideration should be given to the implementation of universal screening for BCVI using neck CTA in all blunt trauma patients. LEVEL OF EVIDENCE: Diagnostic, level III.

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.

Aeromedical retrieval of trauma patients: Impact of flight path model on estimates of population coverage.

BACKGROUND: The aim of this study was to compare the impact of different flight path models on the calculated population coverage of aeromedical retrieval systems, using the state of Alabama as a case study. METHODS: Geospatial analysis of U.S. Census Bureau population data using helicopter bases and trauma centers as foci of either circular or elliptical coverage areas. RESULTS: Circular isochrone models around helicopter bases or trauma centers suggest that the entire population of Alabama could reach a level I or II trauma center within 60 min. Elliptical isochrones, incorporating outbound and inbound flights, suggest that only 78.8% of the population have ready access to level I or II trauma centers. CONCLUSION: While all three flight path models described have some validity and utility, simplistic circular flight time isochrones around trauma centers and helicopter bases provide overly optimistic estimates of population coverage. The elliptical model provides a more realistic evaluation.

Early Identification of Acute Lung Injury in a Porcine Model of Hemorrhagic Shock.

BACKGROUND: Acute lung injury (ALI) is a frequent complication after severe trauma. Lung-protective ventilation strategies and damage control resuscitation have been proposed for the prevention of ALI; however, there are no clinical or laboratory parameters to predict who is at risk of developing ALI after trauma. In the present study, we explored pulmonary inflammatory markers as a potential predictor of ALI using a porcine model of hemorrhagic shock. MATERIALS AND METHODS: Female swine were randomized to mechanical ventilation with low tidal volume (VT) (6 mL/kg) or high VT (12 mL/kg). After equilibration, animals underwent pressure-controlled hemorrhage (mean arterial pressure [MAP] 35 ± 5 mmHg) for 1 h, followed by resuscitation with fresh whole blood or Hextend. They were maintained at MAP of 50 ± 5 mmHg for 3 h in the postresuscitation phase. Bronchoalveolar lavage fluids were collected hourly and analyzed for inflammatory markers. Lung samples were taken, and porcine neutrophil antibody staining was used to evaluate the presence of neutrophils. ELISA evaluated serum porcine surfactant protein D levels. Sham animals were used as negative controls. RESULTS: Pigs that underwent hemorrhagic shock had higher heart rates, lower cardiac output, lower MAPs, and worse acidosis compared with sham at the early time points (P < 0.05 each). There were no significant differences in central venous pressure or pulmonary capillary wedge pressure between groups. Pulmonary neutrophil infiltration, as defined by neutrophil antibody staining on lung samples, was greater in the shock groups regardless of resuscitation fluid (P < 0.05 each). Bronchoalveolar lavage fluid neutrophil levels were not different between groups. There were no differences in levels of porcine surfactant protein D between groups at any time points, and the levels did not change over time in each respective group. CONCLUSIONS: Our study demonstrates the reproducibility of a porcine model of hemorrhagic shock that is consistent with physiologic changes in humans in hemorrhagic shock. Pulmonary neutrophil infiltration may serve as an early marker for ALI; however, the practicality of this finding has yet to be determined.

Population Coverage of Trauma Systems: What Do Helicopters Add?

Trauma is a time-critical condition. Helicopters are thought to enhance the accessibility to trauma centers, but this benefit is poorly quantified. The aim of this study was to conduct a geographical analysis of the added benefit provided by helicopters, over ground transport. This study uses geospatial analysis. Helicopter bases and Level I and II designated trauma centers were geocoded. 60-minute drive-time and elliptical flight-time isochrones were mapped with ArcGIS™ (Esri, Redlands, CA). Calculations included allowance for mission ground time (MGT). We compared the proportion of the population that could be taken to Level I and II trauma centers, within 60 minutes, by road and by air. Using a 30-minute MGT model, helicopters permit 279,317 additional residents (5.8%) access to a Level I trauma center within 60 minutes. Using the 20-minute MGT model, 1,089,177 more residents (22.8%) would have access to Level I trauma center care. The benefits were marginally greater for access to Level I and II trauma center care. Helicopters enhance access to specialist trauma center care, but the benefit is small and dependent on MGT. Consideration should be given to the siting of helicopters, particularly in relation to trauma patients, MGT, and the timely response of EMS when determining the triage for helicopter transport.

Use of helicopters for retrieval of trauma patients: A geospatial analysis.

BACKGROUND: Helicopters are widely used to facilitate the transport of trauma patients, from the scene of an incident to the hospital. However, the use of helicopters may not always be appropriate. The aim of this project was to conduct a geospatial analysis of helicopter transport to a Level I trauma center. METHODS: Retrospective geospatial analysis of trauma registry data, 2013 to 2018. We included all adult (≥16) trauma patients brought to the trauma center directly from the scene. Data were geocoded and analyzed using arcGIS. Drive times and flight times were calculated using Google Maps. Flight times included the time required to reach the incident location. RESULTS: Two thousand eight hundred ninety-three patients were identified, and 1,911 had incident locations recorded and were therefore included in the analysis. The median age was 41 years (interquartile range [IQR], 27-58 years). Twenty-four percent of the patients had suffered severe injuries (Injury Severity Score [ISS], 16-25), 17% very severe injuries (ISS > 25), 24% moderately severe injuries, and 36% minor injuries (ISS, 1-8). The overall geographical distribution was centroidal, although with a concentration of case volume in the vicinity, and to the northeast, of the trauma center. Median flight time was 60 minutes (IQR, 52-69 minutes), and median drive time 65 minutes (IQR, 54-86 minutes). In 33% of the patients, the calculated drive time to the trauma center was shorter than the calculated flight time when considering the time for the helicopter to reach the scene. CONCLUSION: The majority of patients taken to our level I trauma center by helicopter are injured in relatively close proximity. One in four patients is severely or very severely injured, but one third of the patients have only minor injuries. Over a quarter of trauma patients might have reached hospital more quickly if they had been taken by road, rather than helicopter. LEVEL OF EVIDENCE: Epidemiological/geographical study, level V.

Evaluation of a Novel Fibrin Sealant Patch in Hemorrhage Control After Vascular or Hepatic Injury.

INTRODUCTION: Acute hemorrhage remains the leading cause of death in potentially survivable injuries. The use of topical hemostatic agents has increased over the last two decades with the evolution of damage control surgery. By 2008, the military widely adopted Combat Gauze as the hemostatic dressing of choice for compressible hemorrhage. The goal of this study was to compare the performance of a novel fibrin sealant patch to Combat Gauze in two clinically relevant models of hemorrhage. MATERIALS AND METHODS: Yorkshire swine underwent unilateral femoral artery puncture or a grade V liver laceration with timed free bleeding then received either the fibrin patch or Combat Gauze packing with 3 minutes of standardized pressure. Animals were then resuscitated to maintain a mean arterial pressure of 60 mmHg for 4 hours. Hemostasis, blood loss, resuscitation volume, survival, vessel patency, and hematologic parameters were evaluated. RESULTS: Hemostasis was equivalent in both groups after hepatic and vascular injury. Survival was 80% in the fibrin patch vascular injury group and 100% in all other groups. Hematologic parameters were not significantly different between treatment groups. Femoral artery patency was 80% in both groups after vascular injury. With simulated ambulation after vessel injury, 60% of the Combat Gauze group and 80% of the fibrin patch group remained hemostatic (p > 0.05). In simulated re-exploration with packing removal, all animals rebled after hemostatic product removal. CONCLUSION: There was no significant difference in hemostasis between a novel fibrin patch and Combat Gauze after extremity arterial or hepatic injury. This novel fibrin patch may have a clinical advantage over the Combat Gauze, as it can be left in the body, thereby limiting the potential need for reoperation.

En Route Resuscitation - Utilization of CCATT to Transport and Stabilize Critically Injured and Unstable Casualties.

INTRODUCTION: The U.S. Air Force utilizes specialized Critical Care Air Transport Teams (CCATT) for transporting "stabilized" patients. Given the drawdown of military forces from various areas of operation, recent CCATT operations have increasingly involved the evacuation of unstable and incompletely resuscitated patients from far forward, austere locations. This brief report describes unique cases representative of the evolving CCATT mission and provides future direction for changes in doctrine and educational requirements in preparation for en route combat casualty care. METHODS AND MATERIALS: This case series describes three patients who required significant resuscitation during CCATT transport from austere locations between April and November 2017. Approval for this project was received from the US Air Force 59th Medical Wing Institutional Review Board as non-research. RESULTS: Case 1: CCATT was dispatched to transport patient 1 who was reported to have a head injury after a fall. Upon evaluation of the patient onboard the aircraft, it was discovered that the patient was in cardiac arrest. Cardiopulmonary resuscitation was performed during tactical takeoff with frequent combat maneuvers. The patient developed a palpable pulse after three rounds of CPR, three doses of epinephrine, and one unit of packed red blood cells. Point of care laboratory analysis demonstrated a profoundly elevated lactate level. Cyanide poisoning was a concern but there was no antidote available in the available equipment set. After delivery to a medical facility, blood samples were positive for cyanide. Over the next 2 weeks, the patient improved and was discharged home, neurologically intact. Case 2: Patient 2 sustained complex blast injuries and bilateral lower extremity amputations. He required early transport for continuous renal replacement therapy (CRRT). The patient received 200 units of blood products in the 24 hours prior to transport and developed renal failure, pulmonary edema, and elevated ICP. During the 7 hour flight, Patient 2 received frequent adjustments of vasopressor medications, multiple Dakins solution soaks and flushes, and 1 unit of fresh frozen plasma. He remained alive 2 months later. Case 3: The team was notified to collect an urgent patient with a blast lung injury and bilateral lower extremity amputations. The ground team encountered difficulty ventilating the patient. Patient 3 arrived in the back of a pickup truck accompanied by medics and being bag valve mask ventilated with a pulse oximetry reading of 65%. He was secured to the floor of the aircraft which departed within 5 minutes of arrival. An ultrasound of the lungs showed no pneumothorax. By the end of the flight, the patient's oxygen saturation had risen to 95% and he was delivered to the emergency department in stable condition. He later passed away in the operating room due to severe blast lung and cardiac contusion. CONCLUSION: This brief report demonstrates the need of CCATT in the transport of unstable patients from forward deployed locations. The Air Force has adapted and is continuing to adapt CCATT training, equipment, onboard diagnostics and therapies, and team members' clinical skills to meet en route care combat casualty needs.