Strategic air medical evacuation of critically ill patients involving an intensive care physician: A retrospective analysis of 16 years of mission data

The first two years of the use of low titer group O whole blood during French Military overseas operations: A retrospective study

BACKGROUND

On the battlefield, hemorrhage is the main cause of potentially preventable death. To reduce mortality due to hemorrhagic injuries, the French Military Medical Service (FMMS) has deployed low titer group O whole blood (LTOWB) since June 2021 during operation BARKHANE in the Sahel-Saharan strip. Questions persist regarding the circumstances under which the FMMS employs LTOWB during overseas operations.

STUDY DESIGN

We performed a retrospective analysis of all LTOWB transfused by the FMMS during overseas operations in the Sahel-Saharan strip between June 1, 2021, and June 1, 2023. Information was collected from battlefield forward transfusion sheets.

RESULTS

Over the 2-year study period, 40 units of LTOWB were transfused into 25 patients. Of the 25 patients, 18 were combat casualties and seven were transfused for non-trauma surgery. Of the 40 units of LTOWB transfused, 22 were provided during Role 2 care, 11 during tactical medical evacuation (MEDEVAC), and seven in light and mobile surgical units. Among combat casualties, LTOWB was the first blood product transfused in 13 patients. In combat casualties, 6 h post-trauma, the median ratio of plasma: red blood cells (RBCs) was 1.5, and the median equivalent platelet concentrate (PC) transfused was 0.17. No immediate adverse events related to LTOWB transfusion were reported.

CONCLUSION

LTOWB is transfused by the FMMS during overseas operations from the tactical MEDEVAC until Role 2 care. Deployment of LTOWB by the FMMS enables an early high-ratio plasma/RBC transfusion and an early platelet transfusion for combat casualties.

Please get me out of here: The difficult decision making in fit-to-fly assessments for international fixed-wing air ambulance operations

INTRODUCTION

With international travel for leisure and business almost back to pre-pandemic levels, demand for repatriation due to illness and injury abroad is increasing [1,2]. In any repatriation, there is considerable pressure on all involved to organize a rapid transport back home. Delay in such action may be perceived by the patient, relatives, and the public as an attempt by the underwriter to hold off on an expensive air ambulance mission [3-5].

METHODS

Review of the available literature and analysis of assistance and air ambulance Companies' infrastructure and processes to identify risk and benefit of executing or delaying aeromedical transport for international travellers.

KEY FINDINGS

While patients of almost any severity can be safely transported over great distances in modern air ambulance aircraft, immediate transport is not always in the patient's best interest. Each call for assistance requires a complex and dynamic risk-benefit analysis with multiple stakeholders involved to achieve an optimized outcome. Opportunities for risk mitigation within the assistance team include active case management with clearly assigned ownership, as well as medical and logistical experience with knowledge on local treatment opportunities and limitations. On the air ambulance side, modern equipment, experience, standards and procedures as well as accreditation can reduce risk.

CONCLUSIONS

Each patient evaluation remains a highly individual risk-benefit assessment. Optimal outcomes require a clear understanding of responsibilities, flawless communication and significant expertise among the key decision-makers. Negative outcomes are mostly associated with insufficient information, communication, inadequate experience or a lack of ownership/assigned responsibility.

An observational study of the blood use in combat casualties of the French Armed Forces, 2013-2021

BACKGROUND

The French Armed Forces conduct asymmetric warfare in the Sahara-Sahel Strip. Casualties are treated with damage control resuscitation to the extent possible. Questions remain about the feasibility and sustainability of using blood for wider use in austere environments.

METHODS

We performed a retrospective analysis of all French military trauma patients transfused after injury in overseas military operations in Sahel-Saharan Strip, from the point of injury, until day 7, between January 11, 2013 to December 31, 2021.

RESULTS

Forty-five patients were transfused. Twenty-three (51%) of them required four red blood cells units (RBC) or more in the first 24H defining a severe hemorrhage. The median blood product consumption within the first 48 h, was 8 (IQR [3; 18]) units of blood products (BP) for all study population but up to 17 units (IQR [10; 27.5]) for the trauma patients with severe hemorrhage. Transfusion started at prehospital stage for 20 patients (45%) and included several blood products: French lyophilized plasma, RBCs, and whole blood. Patients with severe hemorrhage required a median of 2 [IQR 0; 34] further units of BP from day 3 to day 7 after injury. Eight patients died in theater, 4 with severe hemorrhage and these 4 used an average of 12 products at Role 1 and 2.

CONCLUSION

The transfusion needs were predominant in the first 48 h after the injury but also continued throughout the first week for the most severe trauma patients. Importantly, our study involved a low-intensity conflict, with a small number of injured combatants.

Effects of sequential aeromedical evacuations following traumatic brain injury in swine

INTRODUCTION

Traumatic brain injuries (TBI) represent a significant percentage of critical injuries in military conflicts. Following injury, wounded warfighters are often subjected to multiple aeromedical evacuations (AE) and associated hypobaria, yet the impact in TBI patients remains to be characterized. This study evaluated the impact of two consecutive simulated AEs in a fluid-percussion TBI model in swine to characterize these effects.

METHODS

Following instrumentation, anesthetized Yorkshire swine underwent a frontal TBI via fluid-percussion. A hypobaric chamber was then used to simulate AE at simulated cabin pressure equivalent to 8000ft (hypobaria) in a 6 h initial flight on day 3, followed by a 9 h flight on day 6, and were monitored for 14 days. Animals in the normobaria group were subjected to the same steps at sea level while Sham animals in both groups were instrumented but not injured. Parameters measured included physiologic response, intracranial pressure (ICP), hematology, chemistry, and serum cytokines. Histopathology of brain, lung, intestine, and kidney was performed, as well as fluorojade staining to evaluate neurodegeneration. All animals were divided into sub-groups by block randomization utilizing a 2-way ANOVA to analyze independent variables.

RESULTS

Survival was 100% in all groups. Physiologic parameters were largely similar across groups as well during both 6 and 9 h AE. Animals exposed to hypobaria in both the TBI and Sham groups had elevated heart rate (HR) during the 6 h flight (p<0.05). Three animals in the TBI hypo group demonstrated leukocytosis with histologic evidence of meningeal inflammatory response. Expression of serum cytokines was low across all groups. No significant neuronal degeneration was identified in areas away from the site of injury.

CONCLUSION

Aeromedical evacuation in swine was not associated with significant differences in physiologic measures, cytokine expression or levels of neuronal degeneration. Histological examination revealed higher risk of meningeal inflammatory response and leucocytosis in swine exposed to hypobaria.

Level of Onboard Care for Critical Patients: Analysis of the French Armed Forces Air Medical Evacuations From the Sahel Since 2013

OBJECTIVE

Since 2013, the French Armed Forces have been engaged in the Sahel. The aim of our work was to study the characteristics of severe patients evacuated according to the composition of the air medical staff (ie, an anesthesiologist/intensive care physician [AICP] or an emergency physician [EP]).

METHODS

This was a retrospective cohort analysis including all French service members repatriated from the Sahel with a speedy evacuation priority between 2013 and 2019.

RESULTS

A total of 191 patients were evacuated. The causes were trauma for 103 patients and disease for 88. Trauma patients included war injuries (n = 58) and nonbattle injuries (n = 44). For disease patients, the main pathologies were cardiovascular (n = 17), infectious (n = 17), neurologic (n = 15), and gastrointestinal (n = 12). Highly dependent patients were significantly (P < .001) more likely to be managed by an AICP (n = 41) than an EP (n = 5). Moderately dependent patients managed by an AICP (n = 51) were more frequently unstable hemodynamically (n = 5 vs. n = 0, P < .05) and referred to an intensive care unit (n = 24 vs. n = 2, P < .001) than those managed by an EP (n = 41). There were no deaths in flight.

CONCLUSION

Greater use of EPs, especially for transporting stabilized patients, would provide more personnel trained in long-distance air transport.

Analysis of European Air Medical Evacuation Flights of Coronavirus Disease 2019 Patients

Objective

As part of the humanitarian response to the coronavirus disease 2019 (COVID-19) pandemic, the German and French Armed Forces provided air transport for patients from overwhelmed regional hospitals in Italy and France. The objective of this study was to analyze the characteristics of the missions and the medical conditions of COVID-19 patients transported during an air medical evacuation on fixed wing aircraft in March and April 2020.

Method

This was a retrospective analysis of transport records as well as other documents for 58 COVID-19 patients requiring artificial ventilation.

Results

The median age of the transported patients was 61.5 years, and 61% of them had preexisting medical conditions. They had been ventilated for a median of 5 days and experienced the first symptoms 18 days before transport. The patients flown out of France had less days of ventilation before flight, a lower end-tidal carbon dioxide level at the beginning of the flight, and a lower Charlson Comorbidity Index. There were also some differences between the ventilation and the flight level flown by the 2 air forces.

Conclusion

The intensive care transport of ventilated COVID-19 patients requires highly qualified personnel and appropriate equipment and should be planned appropriately.