Extraglottic device use is rare during emergency airway management: A National Emergency Airway Registry (NEAR) study.

INTRODUCTION: Airway management is a critical component of the management of emergency department (ED) patients. The ED airway literature primarily focuses upon endotracheal intubation; relatively less is known about the ED use of extraglottic devices (EGDs). The goal of this study was to describe the frequency of use, success, and complications for EGDs among ED patients. METHODS: The National Emergency Airway Registry (NEAR) is a prospective, multi-center, observational registry. It captures data on all ED patients at participating sites requiring airway management. Intubating clinicians entered all data into an online system as soon as practical after each encounter. We conducted a secondary analysis of these data for all ED encounters in which EGD placement occurred. We used descriptive statistics to characterize these encounters. RESULTS: Of 19,071 patients undergoing intubation attempts, 56 (0.3%) underwent EGD placement. Of 25 participating sites, 13 reported no cases undergoing EGD placement; the median number of EGDs placed per site was 2 (interquartile range 1-2.5, range 1-31). Twenty-nine (54%) patients had either hypotension or hypoxia prior to the start of airway management. Clinicians reported anticipation of a difficult airway in 55% and at least one difficult airway characteristic in 93% of these patients. Forty-one encounters entailed placement of a laryngeal mask airway (LMA®) Fastrach™, 33 of whom underwent subsequent successful intubation through the EGD and 7 of whom underwent intubation by alternative methods. An additional 10 encounters utilized a standard LMA® device. Providers placed 34 (61%) EGDs during the first intubation attempt. Seventeen EGD patients (30%) experienced peri-procedure adverse events, including 14 (25%) experiencing hypoxemia. None of these patients expired due to failed airways. CONCLUSIONS: EGD use was rare in this multi-center ED registry. EGD occurred predominantly in patients with difficult airway characteristics with favorable airway management outcomes. Clinicians should consider this emergency airway device for patients with a suspected difficult airway.

Portable Medical Suction and Aspirator Devices: Are the Design and Performance Standards Relevant?

Airway clearance refers to the clearing of any airway blockage caused due to foreign objects such as mud, gravel, and biomaterials such as blood, vomit, or teeth fragments using the technology of choice, portable suction devices. Currently available devices are either too heavy and bulky to be carried, or insufficiently powered to be useful despite being in accordance with the ISO 10079-1 standards. When applied to portable suction, the design and testing standards lack clinical relevancy, which is evidenced by how available portable suction devices are sparingly used in pre-hospital situations. Lack of clinical relevancy despite being in accordance with design/manufacturing standards arise due to little if any collaboration between those developing clinical standards and the bodies that maintain design and manufacturing standards. An updated set of standards is required that accurately reflects evidence-based requirements and specifications, which should promote valid, rational, and relevant engineering designs and manufacturing standards in consideration of the unique scenarios facing prehospital casualty care. This paper aims to critically review the existing standards for portable suction devices and propose modifications based on the evidence and requirements, especially for civilian prehospital and combat casualty care situations.

Prehospital Interventions Performed on Pediatric Trauma Patients in Iraq and Afghanistan.

BACKGROUND: United States (US) and coalition military medical units deployed to combat zones frequently encounter pediatric trauma patients. Pediatric patients may present unique challenges due to their anatomical and physiological characteristics and most military prehospital providers lack pediatric-specific training. A minimal amount of data exists to illuminate the prehospital care of pediatric patients in this environment. We describe the prehospital care of pediatric trauma patients in Iraq and Afghanistan. METHODS: We queried the Department of Defense Trauma Registry (DODTR) for all pediatric subjects admitted to US and Coalition fixed-facility hospitals in Iraq and Afghanistan from January 2007 to January 2016. Subjects were grouped by age: <1, 1-4, 5-9, 10-14, and 15-17 years. We focused our analysis on interventions related to trauma resuscitation. RESULTS: Of 42,790 encounters in the DODTR during the study period, 3,439 (8.0%) were aged <18 years. Most subjects were in the 5-9 age group (33.1%), male (77.1%), located in Afghanistan (67.8%), injured by explosives (43.1%). Most subjects survived to hospital discharge (90.2%). The most frequently performed interventions were tourniquet placement (6.6%), intubation (6.1%), supplemental oxygen (11.7%), IV access (24.8%), IV fluids (13.3%), IO access (5.1%), and hypothermia prevention (44.5%). The most frequently administered medications were antibiotics (6.2%) and opioids (15.0%). Most procedural and medication interventions occurred in subjects injured by explosives (43.1%) and gunshot wounds (22.1%). CONCLUSIONS: Pediatric subjects comprised over 1 in 13 casualties treated in the joint theaters with the majority injured by explosives. Vascular access and hypothermia prevention interventions were the most frequently performed procedures.

Do Orthostatic Vital Signs Have Utility in the Evaluation of Syncope?

BACKGROUND: Syncope is a common presentation in the emergency department (ED). The differential diagnosis is long and includes benign conditions as well as acute life threats, such as dysrhythmias or pulmonary embolism. OBJECTIVE: The specific goals of this review are twofold: 1) to define the diagnostic utility of orthostatic vital signs (OVS) as a test for orthostatic syncope, and 2) to determine whether OVS help diagnose or exclude life-threatening causes of syncope in ED patients. METHODS: Three prospective cohort studies plus 2017 national guidelines for syncope management were identified, reviewed, and critically appraised. RESULTS: This literature review found that orthostatic hypotension is common among ED patients with syncope and is often diagnosed as the cause of syncope. CONCLUSIONS: OVS measurements do not, in isolation, reliably diagnose or exclude orthostatic syncope, nor do they appear to have value in ruling out life-threatening causes of syncope.

Advancing Combat Casualty Care Statistics and Other Battlefield Care Metrics.

Aggregate statistics can provide intra-conflict and inter-conflict mortality comparisons and trends within and between U.S. combat operations. However, capturing individual-level data to evaluate medical and non-medical factors that influence combat casualty mortality has historically proven difficult. The Department of Defense (DoD) Trauma Registry, developed as an integral component of the Joint Trauma System during recent conflicts in Afghanistan and Iraq, has amassed individual-level data that have afforded greater opportunity for a variety of analyses and comparisons. Although aggregate statistics are easily calculated and commonly used across the DoD, other issues that require consideration include the impact of individual medical interventions, non-medical factors, non-battle-injured casualties, and incomplete or missing medical data, especially for prehospital care and forward surgical team care. Needed are novel methods to address these issues in order to provide a clearer interpretation of aggregate statistics and to highlight solutions that will ultimately increase survival and eliminate preventable death on the battlefield. Although many U.S. military combat fatalities sustain injuries deemed non-survivable, survival among these casualties might be improved using primary and secondary prevention strategies that prevent injury or reduce injury severity. The current commentary proposes adjustments to traditional aggregate combat casualty care statistics by integrating statistics from the DoD Military Trauma Mortality Review process as conducted by the Joint Trauma System and Armed Forces Medical Examiner System.

Ethical challenges in Emergency Medical Services: controversies and recommendations.

Emergency Medical Services (EMS) providers face many ethical issues while providing prehospital care to children and adults. Although provider judgment plays a large role in the resolution of conflicts at the scene, it is important to establish protocols and policies, when possible, to address these high-risk and complex situations. This article describes some of the common situations with ethical underpinnings encountered by EMS personnel and managers including denying or delaying transport of patients with non-emergency conditions, use of lights and sirens for patient transport, determination of medical futility in the field, termination of resuscitation, restriction of EMS provider duty hours to prevent fatigue, substance abuse by EMS providers, disaster triage and difficulty in switching from individual care to mass-casualty care, and the challenges of child maltreatment recognition and reporting. A series of ethical questions are proposed, followed by a review of the literature and, when possible, recommendations for management.

Lessons from the Fallen: An After-Action Review of Prehospital Casualty Data during the Global War on Terror.

BACKGROUND: The US military's recent involvement in long standing conflict has caused the pioneering of many lifesaving medical advances, often made possible by data-driven research. However, future advances in battlefield medicine will likely require greater data fidelity than is currently attainable. Continuing to improve survival rates will require data which establishes the relative contributions to preventable mortality and guides future interventions. Prehospital data, particularly that from Tactical Combat Casualty Care (TCCC) Cards and TCCC After Action Reports (TCCC AARs), are notoriously inconsistent in reaching searchable databases for formal evaluation. While the military has begun incorporating more modern technology in advanced data capture over the past few years like the Air Force's Battlefield Assisted Trauma Distributed Observation Kit (BATDOK) and the Army's Medical Hands-free Unified Broadcast system (MEDHUB), more analysis weighing the advantages and disadvantages of substituting analog solutions is needed. DISCUSSION: We propose 3 changes which may aid prehospital data capture and facilitate analysis: reexamine the current format of TCCC Cards and consider reducing the number of available datapoints to streamline completion, implement a military-wide mandate for all Role 1 providers to complete a TCCC AAR within 24 hours of a casualty event, and formalize the process of requesting de-identified data from the Armed Forces Medical Examiner System (AFMES) database. CONCLUSION: Reflecting on the state of US military medicine after 20 years of war, an important focus is improving the way prehospital data is gathered and analyzed by the military. There are steps we can take now to enhance our capabilities.

Airway Management during Large-Scale Combat Operations: A Narrative Review of Capability Requirements.

Large-scale combat and multi-domain operations will pose unprecedented challenges to the military healthcare system. This scoping review examines the specific challenges related to the management of airway compromise, the second leading cause of potentially preventable death on the battlefield. Closing existing capability gaps will require a comprehensive approach across all components of the Joint Capabilities Integration Development System. In this, we present the case for a change in doctrine to selectively provide definitive airway management in prehospital settings to maximize the effectiveness of limited resources. Organizational changes to optimize training and efficiency in delivery of complex airway intervention include centralization of assigned healthcare personnel. Training must vastly increase opportunities for live tissue and patient experiences to obtain repetitions of both non-invasive and definitive airway procedures. Potential materiel solutions include extra-glottic devices, bag-valve masks, video laryngoscopes, and oxygen generators all ruggedized and capable of operations in austere settings. Leadership and education changes must formalize more robust airway skills into the initial training curricula for more healthcare personnel who will potentially need to perform these life-saving interventions. Simultaneously, personnel changes should expand authorizations for clinicians with advanced airway skills to the lowest echelons of care. Finally, existing medical training and treatment facilities must expand as necessary to accommodate the training and skill maintenance of these personnel.

Placement of Antibiotic Powder in Open Fracture Wounds during the Emergency Room (POWDER): Design and Rationale for an Investigation of the Acute Application of Topical Antibiotic Powder in Open Fracture Wounds for Infection Prophylaxis.

BACKGROUND: Open fractures are at high risk for complications both in the military and civilian setting. Treatments to prevent fractures are limited in the Role 1 (prehospital, battalion aid station) setting. The goal of this study is to assess the efficacy of topical vancomycin powder, administered within 24 hours of an open fracture injury, in the prevention of infection and infection-related complications. METHODS: The POWDER study is a multicenter, prospective, randomized controlled clinical trial using a pragmatic open-label design. We will recruit 200 long bone open fracture patients from University Hospital at University of Texas Health at San Antonio (UTHSA) and the Brooke Army Medical Center (BAMC). We will screen and randomize patients in a 1:1 ratio to receive either usual care plus 2g topical vancomycin or usual care only. The primary objective of this study is to compare the proportion of infection and infection-related complications which occur in the 2 arms. An additional objective is to develop a risk-prediction model for open fracture wound complications. CONCLUSIONS: The infection rates seen in open fractures remain alarmingly high in both combat and civilian settings. Several orthopedic surgery studies suggest vancomycin powder is effective in reducing surgical site infections when applied topically at the time of wound closure. We expect to see a reduction in infections in open fracture injuries treated acutely with vancomycin powder. This study may provide important information regarding the use of local vancomycin powder during the acute treatment of open fractures. If shown to be efficacious, vancomycin powder could provide a simple, time- and cost-effective infection prophylaxis strategy for these injuries.

Outcomes after Prehospital Cricothyrotomy.

BACKGROUND: Prehospital surgical cricothyrotomies and complications from placement are an important and under-evaluated topic for both the military and civilian prehospital populations. This study uses the Department of Defense Trauma Registry to identify complications and the incidence of complications in prehospital combat surgical cricothyrotomies. METHODS: A secondary analysis of previously described prehospital-based dataset from the Department of Defense Trauma Registry (DODTR) was performed. Casualties who had a prehospital cricothyrotomy performed were isolated and assessed for documented airway injuries and surgical procedures after hospital admission. RESULTS: There were 25,8976 casualties in the original dataset, of which 251 met inclusion for this analysis. The median age was 25 and most (98%) were male. Explosives were most frequent (55%) followed by firearm (33%) mechanisms. Most were host nation partner forces (35%) and humanitarian (32%) casualties. The median injury severity score was 24. The most frequent seriously injured body region was the head/neck (61%). Most (61%) were discharged alive. Within the 251, 14% had a complication noted, most commonly requiring tracheostomy revision (5%). CONCLUSIONS: Cricothyrotomies are rarely performed, but when they are performed and the casualty survives long enough to reach a military treatment facility with surgical capabilities, the incidence of near-term and long-term complications is high. A better understanding of outcomes associated with this procedure will enable more targeted training and technology development.

Descriptive Analysis of Combat-Associated Aspiration Pneumonia.

BACKGROUND: Airway obstruction is the second leading cause of potentially preventable death on the battlefield. The treatment for airway obstruction is intubation or advanced airway adjunct, which has a known risk of aspiration. We sought to describe the variables associated with aspiration pneumonia after prehospital airway intervention. METHODS: This is a sub-analysis of previously described data from the Department of Defense Trauma Registry (DoDTR) from 2007 to 2020. We included casualties that had at least one prehospital airway intervention with documentation of subsequent aspiration pneumonia or pneumonia within three days of the intervention. We used a generalized linear model with Firth bias estimates to test for associations. RESULTS: There were 1,509 casualties that underwent prehospital airway device placement. Of these, 41 (2.7%) met inclusion criteria into the aspiration pneumonia cohort. The demographics had no statistical difference between the groups. The non-aspiration cohort had fewer median ventilator days (2 versus 6, p < 0.001), intensive care unit days (2 versus 7, p < 0.001, and hospital days [3 versus 8, p < 0.001]). Survival was lower in the non-aspiration cohort (74.2% versus 90.2%, p = 0.017). The administration of succinylcholine was higher in the non-aspiration cohort (28.0% versus 12.2%, p = 0.031). In our multivariable model, only the administration of succinylcholine was significant and was associated with lower probability of aspiration pneumonia (odds ratio 0.56). CONCLUSION: Overall, the incidence of aspiration pneumonia was low in our cohort. The administration of succinylcholine was associated with a lower odds of developing aspiration pneumonia.

Improving Outcomes Associated with Prehospital Combat Airway Interventions: An Unrealized Opportunity.

BACKGROUND: Airway obstruction is the second leading cause of potentially survivable death on the battlefield. Assessing outcomes associated with airway interventions is important, and temporal trends can reflect the influence of training, technology, the system of care, and other factors. We assessed mortality among casualties undergoing prehospital airway intervention occurring over the course of combat operations during 2007-2019. METHODS: This is a retrospective analysis of a previously described dataset from the Department of Defense Trauma Registry (DODTR). We included only casualties with documented placement of an endotracheal tube, cricothyrotomy, or supraglottic airway (SGA) in the prehospital setting. RESULTS: Within the DODTR from January 2007 to December 2019, there were 25,849 adult encounters with documentation of any prehospital activity. Within that group, there were 251 documented cricothyrotomies, 1,147 documented intubations, and 35 documented supraglottic airways placed. Cricothyrotomy recipients had a median age of 25. Within this group, the largest proportion were non-North Atlantic Treaty Organization (NATO) military personnel (35%), were injured by explosives (54%), had a median injury severity score (ISS) of 24, and 60% survived to hospital discharge. Intubation recipients had a median age of 24. Within this group, the largest proportion were non-NATO military personnel (37%), were injured by explosives (57%), had a median ISS of 18, and 76% survived to hospital discharge. SGA recipients had a median age of 28. Within this group, the largest proportion were non-NATO military (37%), were injured by firearms (48%), had a median ISS of 25, and 54% survived to hospital discharge. A downward trend existed in the quantity of all procedures performed during the study period. In both unadjusted and adjusted regression models, we identified no year-to-year differences in survival after prehospital cricothyrotomy or SGA placement. In the unadjusted and adjusted models, we noted a decrease in mortality during the 2007-2008 (odds ratio [OR] for death 0.47, 95% CI 0.26-0.86) and an increase from 2012-2013 (OR 2.10, 95% CI 1.09-4.05) for prehospital intubation. CONCLUSION: Mortality among combat casualties undergoing prehospital or emergency department airway interventions showed no sustained change during the study period. These findings suggest that advances in airway resuscitation are necessary to achieve mortality improvements in potentially survivable airway injuries in the prehospital setting.

Military Standard Testing of Commercially Available Supraglottic Airway Devices for Use in a Military Combat Setting.

INTRODUCTION: Airway obstruction is the second leading cause of death on the battlefield. The harsh conditions of the military combat setting require that devices be able to withstand extreme circumstances. Military standards (MIL-STD) testing is necessary before devices are fielded. We sought to determine the ability of supraglottic airway (SGA) devices to withstand MIL-STD testing. METHODS: We tested 10 SGA models according to nine MIL-STD-810H test methods. We selected these tests by polling five military and civilian emergency-medicine subject matter experts (SMEs), who weighed the relevance of each test. We performed tests on three devices for each model, with operational and visual examinations, to assign a score (1 to 10) for each device after each test. We calculated the final score of each SGA model by averaging the score of each device and multiplying that by the weight for each test, for a possible final score of 2.6 to 26.3. RESULTS: The scores for the SGA models were LMA Classic Airway, 25.9; AuraGain Disposable Laryngeal Mask, 25.5; i-gel Supraglottic Airway, 25.2; Solus Laryngeal Mask Airway, 24.4; LMA Fastrach Airway, 24.4; AuraStraight Disposable Laryngeal Mask, 24.1; King LTS-D Disposable Laryngeal Tube, 22.1; LMA Supreme Airway, 21.0; air-Q Disposable Intubating Laryngeal Airway, 20.1; and Baska Mask Supraglottic Airway, 18.1. The limited (one to three) samples available for testing provide adequate preliminary information but restrict the range of failures that could be discovered. CONCLUSIONS: Lower scoring SGA models may not be optimal for military field use. Models scoring sufficiently close to the top performers (LMA Classic, AuraGain, i-gel, Solus, LMA Fastrach, AuraStraight) may be viable for use in the military setting. The findings of our testing should help guide device procurement appropriate for different battlefield conditions.

Expert Consensus Panel Recommendations for Selection of the Optimal Supraglottic Airway Device for Inclusion to the Medic's Aid Bag.

INTRODUCTION: Airway obstruction is the second leading cause of potentially survivable death on the battlefield. The Committee on Tactical Combat Casualty Care (CoTCCC) has evolving recommendations for the optimal supraglottic airway (SGA) device for inclusion to the medics' aid bag. METHODS: We convened an expert consensus panel consisting of a mix of 8 prehospital specialists, emergency medicine experts, and experienced combat medics, with the intent to offer recommendations for optimal SGA selection. Prior to meeting, we independently reviewed previously published studies conducted by our study team, conducted a virtual meeting, and summarized the findings to the panel. The studies included an analysis of end-user after action reviews, a market analysis, engineering testing, and prospective feedback from combat medics. The panel members then made recommendations regarding their top 3 choices of devices including the options of military custom design. Simple descriptive statistics were used to analyze panel recommendations. RESULTS: The preponderance (7/8, 88%) of panel members recommended the gel-cuffed SGA, followed by the self-inflating-cuff SGA (5/8, 62%) and laryngeal tube SGA (5/8, 62%). Panel members expressed concerns primarily related to the (1) devices' tolerance for the military environment, and (2) ability to effectively secure the gel-cuffed SGA and the self-inflating-cuff SGA during transport. CONCLUSIONS: A preponderance of panel members selected the gel-cuff SGA with substantial feedback highlighting the need for military-specific customizations to support the combat environment needs.

Does a simple bedside sonographic measurement of the inferior vena cava correlate to central venous pressure?

BACKGROUND: Bedside ultrasound has been suggested as a non-invasive modality to estimate central venous pressure (CVP). OBJECTIVE: Evaluate a simple bedside ultrasound technique to measure the diameter of the inferior vena cava (IVC) and correlate to simultaneously measured CVP. Secondary comparisons include anatomic location, probe orientation, and phase of respiration. METHODS: An unblinded prospective observation study was performed in an emergency department and critical care unit. Subjects were a convenience sample of adult patients with a central line at the superior venocaval-atrial junction. Ultrasound measured transverse and longitudinal diameters of the IVC at the subxiphoid, suprailiac, and mid-abdomen, each measured at end-inspiration and end-expiration. Correlation and regression analysis were used to relate CVP and IVC diameters. RESULTS: There were 72 subjects with a mean age of 67 years (range 21-94 years), 37 (53%) male, enrolled over 9 months. Seven subjects were excluded for tricuspid valvulopathy. Primary diagnoses were: respiratory failure 12 (18%), sepsis 11 (17%), and pancreatitis 3 (5%). There were 28 (43%) patients mechanically ventilated. Adequate measurements were obtainable in 57 (89%) using the subxiphoid, in 44 (68%) using the mid-abdomen, and in 28 (43%) using the suprailiac views. The correlation coefficients were statistically significant at 0.49 (95% confidence interval [CI] 0.26-0.66), 0.51 (95% CI 0.23-0.71), and 0.50 (95% CI 0.14-0.74) for end-inspiratory longitudinal subxiphoid, midpoint, and suprailiac views, respectively. Transverse values were statistically significant at 0.42 (95% CI 0.18-0.61), 0.38 (95% CI 0.09-0.61), and 0.67 (95% CI 0.40-0.84), respectively. End-expiratory measurements gave similar or slightly less significant values. CONCLUSION: The subxiphoid was the most reliably viewed of the three anatomic locations; however, the suprailiac view produced superior correlations to the CVP. Longitudinal views generally outperformed transverse views. A simple ultrasound measure of the IVC yields weak correlation to the CVP.

Emergent interfacility evacuation of critical care patients in combat.

During the Second Iraq War (Operation Iraqi Freedom), high-intensity, low-utilization medical and surgical services, such as neurosurgical care, were consolidated into a centralized location within the combat zone. This arrangement necessitated intra-theater air medical evacuation of critically ill or injured patients from outlying combat support hospitals (CSH) to another combat zone facility having the needed services. A case series is presented of intratheater transfer of neurosurgical patients in Iraq during 2005-06. Ninety-eight patients are included in the series, with typical transfer distances of 40 miles (approximately 20-25 minutes of flight time). All patients were transported with a CSH nurse in addition to the standard Army EMT-B flight medic. Seventy-six percent of cases were battle injury, 17% were non-battle injuries, and the balance were classified as non-injury mechanisms. Seventy-six percent of cases were head injuries, with the balance involving burns, stroke, and other injuries. At 30 days, 12% of the patients had died, and 9% remained hospitalized in a critical care setting. None of the patients died during evacuation. Intratheater and interfacility transfer of critical care patients in the combat theater often involves severely head-injured and other neurosurgical cases. Current Army staffing for helicopter transport in these case requires a nurse or other advanced personnel to supplement the standard EMT-B flight medic.

The Use of Portable Oxygen Concentrators in Low-Resource Settings: A Systematic Review.

INTRODUCTION: Portable oxygen concentrators (POCs) are medical devices that use physical means to separate oxygen from the atmosphere to produce concentrated, medical-grade gas. Providing oxygen to low-resources environments, such as austere locations, military combat zones, rural Emergency Medical Services (EMS), and during disasters, becomes expensive and logistically intensive. Recent advances in separation technology have promoted the development of POC systems ruggedized for austere use. This review provides a comprehensive summary of the available data regarding POCs in these challenge environments. METHODS: PubMed, Google Scholar, and the Defense Technical Information Center were searched from inception to November 2021. Articles addressing the use of POCs in low-resource settings were selected. Three authors were independently involved in the search, review, and synthesis of the articles. Evidence was graded using Oxford Centre for Evidence-Based Medicine guidelines. RESULTS: The initial search identified 349 articles, of which 40 articles were included in the review. A total of 724 study subjects were associated with the included articles. There were no Level I systematic reviews or randomized controlled trials. DISCUSSION: Generally, POCs are a low-cost, light-weight tool that may fill gaps in austere, military, veterinary, EMS, and disaster medicine. They are cost-effective in low-resource areas, such as rural and high-altitude hospitals in developing nations, despite relatively high capital costs associated with initial equipment purchase. Implementation of POC in low-resource locations is limited primarily on access to electricity but can otherwise operate for thousands of hours without maintenance. They provide a unique advantage in combat operations as there is no risk of explosive if oxygen tanks are struck by high-velocity projectiles. Despite their deployment throughout the battlespace, there were no manuscripts identified during the review involving the efficacy of POCs for combat casualties or clinical outcomes in combat. Veterinary medicine and animal studies have provided the most robust data on the physiological effectiveness of POCs. The success of POCs during the coronavirus disease 2019 (COVID-19) pandemic highlights the potential for POCs during future mass-casualty events. There is emerging technology available that combines a larger oxygen concentrator with a compressor system capable of refilling small oxygen cylinders, which could transform the delivery of oxygen in austere environments if ruggedized and miniaturized. Future clinical research is needed to quantify the clinical efficacy of POCs in low-resource settings.