Preparing Future Military Medical Officers to Conduct Emergency Fresh Whole Blood Transfusions in Austere Environments: A Novel Training Curriculum

ABSTRACT

Introduction

Providing resilient Damage Control Resuscitation capabilities as close to the point of injury as possible is paramount to reducing mortality and improving patient outcomes for our nation’s warfighters. Emergency Fresh Whole Blood Transfusions (EFWBT) play a critical role in supporting this capability, especially in future large-scale combat operations against peer adversaries with expected large patient volumes, restrictive operating environments, and unreliable logistical supply lines. Although there are service-specific training programs for whole blood transfusion, there is currently no dedicated EFWBT training for future military medical officers. To address this gap, we developed, implemented, and evaluated a training program to enhance EFWBT proficiency in third-year military medical students at the F. Edward Hebert School of Medicine at the USU.

Materials and Methods

After reviewing both the 75th Ranger Regiment Ranger O-Low Titer program and the Marine Corps’ Valkyrie program, along with the relevant Joint Trauma System Clinical Practice Guidelines, we created a streamlined and abbreviated training curriculum. The training consisted of both online preparatory materials as well as a 2-hour in-person training that included didactic and experiential learning components. Participants were 165 active duty third-year medical students at USU. Participants were assessed using a pre- and post-assessment self-reported questionnaire on their confidence in the practical application and administrative oversight requirements of an EFWBT program. Participants’ performance was also assessed using a pre/post knowledge assessment consisting of 10 multiple choice questions identified as critical to understanding of the academic principles of EFWBT along with the baseline questionnaire.

Results

Differences in the mean scores of the pre- and post-assessment self-reported questionnaire (increased from 2.32 to 3.95) were statistically significant (P < .001). Similarly, there was a statistically significant improvement in student test scores, with the mean score increasing by approximately 3 points or 30%. There was no significant difference in student confidence assessment or test scores based on branch of service. Students who had previously deployed did not show a statistically significant difference in scores compared to students who had not previously deployed.

Conclusions

Our results suggest that the implementation of streamlined EFWBT training into the undergraduate medical education of future military medical officers offers an efficient way to improve their baseline proficiency in EFWBTs. Future research is needed to assess the impact of this training on real-world applications in forward-deployed environments.

INTRODUCTION

The major principle of Damage Control Resuscitation (DCR) is to restore homeostasis, prevent or mitigate the development of tissue hypoxia, oxygen debt and burden of shock, and prevent coagulopathy.¹ Providing robust DCR capabilities to patients as close to the point of injury as possible is of critical importance to address critical vulnerabilities in patient care capabilities for forward-deployed operational forces in austere and resource-limited environments.² Furthermore, Mass Casualty Incidents, or even just 1 patient experiencing a massive hemorrhage, can rapidly deplete limited stores of cold-stored whole blood and blood component therapies at both large and small MTFs, thereby degrading their DCR capabilities.³ Effective implementation of Walking Blood Banks and sustained training of health care teams, both on the battlefield and in MTFs, in Emergency Fresh Whole Blood Transfusions (EFWBT) is of paramount importance as it can significantly enhance the ability to provide DCR to critically injured patients in emergencies because of logistical constraints.⁴

Need for EFWBT Training in the Undergraduate Medical Education of Future Military Medical Officers

The military medical officer fulfills many critical roles in operational units ensuring that our nation’s warfighters are fully medically ready, providing routine treatment of minor injuries and Disease Non-Battle Injuries, executing administration of the unit’s medical programs, and overseeing the training of enlisted medical personnel under their supervision.^5,6 Aspiring military physicians receive their undergraduate medical training primarily by either attending civilian medical school, through the Armed Forces HPSP, or by attending the USU, a federal medical school with a military-unique curriculum.^5,6

Problem Statement

Although there are service-specific training programs for EFWBT, there is currently no dedicated EFWBT training for future military medical officers based on our team’s review of published literature and established EFWBT training programs in the U.S. Military.^7–11 Additionally, the period of instruction at civilian medical schools varies widely and, with few exceptions, often lacks dedicated military-specific curricula that are crucial to preparing military physicians for their first deployment.⁶ Without appropriate training during their undergraduate medical education, new military medical officers may not be adequately prepared to perform or supervise EFWBT in operational environments. As medical officers are ultimately responsible for the administration and implementation of their units’ EFWBT programs, the development of an EFWBT curriculum is warranted.

Review of EFWBT Training in the U.S. Military

When used appropriately, EFWBT possesses the unparalleled capacity to address the challenges of treating critically injured patients in emergency situations and resource-limited environments.^1,4,12–14 However, a rigorous and standardized EFWBT curriculum is required in order for this critical life-saving skill to be performed effectively and safely in an operational environment.

Although medics and physicians have been trained to perform EFWBT during large-scale combat operations since the turn of the twentieth century,^15,16 the current implementation of EFWBT training varies widely across the services and their subordinate components. For example, in the U.S. Army, the 75th Ranger Regiment has served as the vanguard of institutional adoption of a robust EFWBT training curriculum for their medics, physicians, and physician assistants.^7–9,14 The 75th Ranger Regiment experienced one of the highest operational tempos during the Global War on Terror and quickly identified their lack of DCR capabilities to treat injured Rangers as close to the point of injury as possible.^7–9,14

Identifying the critical need to improve their DCR capabilities, medics and senior medical officers from the 75th Ranger Regiment seized the initiative and developed the Ranger O Low Titer (ROLO) Blood Program which trained and equipped their medical personnel to treat critically injured warfighters.^7–9,14 Their efforts saved many lives and their accomplishments were recognized by receiving the Army’s Greatest Innovation Award at the 2017 Association of the U.S. Army Global Warfare Symposium.^8,9

The U.S. Marine Corps has also found immense success in the adoption and implementation of an EFWBT training program which builds upon the foundations of the ROLO program but is specifically designed for use by the conventional forces of the Marine Corps Ground Combat Element.^10,11 In 2017, the Marine Corps collaborated with the founders of the ROLO program to design and implement the Valkyrie EFWBT Training program—a unique 4-day EFWBT training curriculum that incorporates autologous blood transfusions into the framework of a high-fidelity Tactical Combat Casualty Care (TCCC) assessment to prepare Navy Corpsmen and medical providers attached to Marine Corps Ground Combat Element forces to treat battlefield casualties resulting in hundreds of Marines, Corpsmen, and medical providers being trained in EFWBT over the last 5 years.^10,11

Although significant improvements have been made in training medics and physicians to perform DCR,¹⁵ they are still beholden to the inherent limitations of providing medical care on the battlefield: (1) Tyranny of distance requiring prolonged transport of patients and supplies across vast areas of operations; (2) logistical requirements to appropriately store blood products; and (3) large quantities of resources required in the treatment of just one severely injured casualty.^16,17

Therefore, fresh whole blood serves as the logical choice for providing a cost-effective solution to overcoming these constraints. As put simply in a recent study, “There is one single product [fresh whole blood] available on target which contains all the clotting factors, has fully functioning red blood cells and platelets, costs less than $100 per unit to collect, and is maintained indefinitely at 98.6 degrees Fahrenheit.”¹⁴ Furthermore, a 2017 retrospective study found a 4-fold decrease in patient mortality when the first unit of blood was administered within 36 minutes of the point of injury.¹⁸

Research Team

In order to identify and evaluate gaps in EFWBT training within the undergraduate medical education of future military medical officers, we gathered a research team of subject matter experts, consisting of 4 senior board-certified emergency medicine physicians who are faculty at USU, an Army Special Operations medic, a Navy Special Operations Independent Duty Corpsman, 2 Navy Corpsmen, and a Ph.D. curriculum researcher. Conducting a thorough review of the ROLO and Valkyrie-established EFWBT training curriculums, our team elucidated common foundational concepts and identified best practices in the application of EFWBT.

Curriculum Development

After reviewing both of the ROLO and Valkyrie curriculums, along with the relevant Joint Trauma System (JTS) Clinical Practice Guidelines (CPGs), we created a streamlined and abbreviated training curriculum for military medical students.^1,4,7–14 The training drew heavily from the Valkyrie curriculum and was divided into 5 learning modules (Supplementary Appendix A). These 5 modules were chosen as they were determined to cover the critical knowledge components covered in the JTS CPGs required to successfully, and safely, conduct an EFWBT. The training consisted of 5 online learning modules (Supplementary Appendix A) as well as a 2-hour in-person training which included a PowerPoint presentation summarizing information from the 5 learning modules, demonstration of the EFWBT in accordance with the assessment rubric by 2 subject matter experts, and hands-on experiential learning components at 4 different skills stations as outlined in Supplementary Appendix B.

Purpose

The purpose of this study was to determine the effectiveness of a new, and safe, EFWBT curriculum focused on knowledge, skills, and confidence of future military medical officers.

METHODS

Institutional Review Board (Human Subjects)

This study was approved by the USU Institutional Review Board (IRB) (DBS.2022.362).

Participants

A total of 165 third-year medical students at the USU participated in the training. Every branch of the armed forces with a Medical Corps component was represented and all 165 students were on active duty, including 46 from the Air Force, 62 from the Army, 55 from the Navy, and 2 from the USPHS.

Curriculum Implementation

We implemented this curriculum with third-year medical students at the USU on March 9, 2023 before their deployment to a military medical field practicum. The pre-training preparatory materials (Supplementary Appendix A) were posted on Canvas, the USU online learning platform, 2 weeks before the in-person didactic day. The in-person portion of the training was administered in two 2-hour blocks on March 9, 2023 with 83 participants in the first block and 82 participants in the second block. Testing conditions and instructional information were identical in both blocks of instruction. The in-person training began with administration of a 10-question pre-test knowledge assessment to determine how well the students had retained information from the 5 online learning modules. Additionally, the students were administered the baseline self-reported questionnaire (Supplementary Appendix C) to assess perceived confidence on the knowledge required to conduct an EFWBT. Both of these were immediately followed by a 30-minute review PowerPoint that included familiarization with the EFWBT skill assessment rubric.

Following the presentation, 2 separate small group demonstrations of an EFWBT were conducted on an Intravenous access simulation trainer (Supplementary Fig. S1) by 2 subject matter experts (Supplementary Fig. S2). Students were then divided into 4 groups of approximately 20 students each rotating every 20 minutes between different skills stations proctored by a subject matter expert (Supplementary Appendix B).

Immediately following completion of the skills stations, all students were administered the Post-knowledge test with the same questions as the Pre-test (Supplementary Appendix D) to assess whether there was any significant increase in the students’ performance along with the Post-training self-reported questionnaire which utilized the same Likert-scale model as the Pre-questionnaire to assess whether there was any self-reported increase in perceived confidence of students’ knowledge required to conduct an EFWBT.

Data Collection

Participants were given a pre-assessment questionnaire (Supplementary Appendix C) that consisted of self-reported demographic information including: Branch of service, previously held MOS or Navy Enlisted Classification, length of experience in months, any previous/current certifications in health care and length held months, number of deployments, number of combat deployments, experience with previous training on EFWBTs, previous experiencing collecting a unit of blood in a civilian health care setting, MTFs, military training, or in an operational/combat environment. Both the pre- and post-assessment self-reported questionnaire consisted of the same 8 Likert-scale items asking students to self-report their perceived confidence as, “1—not confident at all, 2—slightly confident but still with major concerns, 3—neither, 4—fairly confident, 5—extremely confident,” on having the appropriate knowledge required to conduct critical subtasks related to EFWBTs (Supplementary Appendix C).

Additionally, students were administered a 10-question pre-training knowledge assessment (Supplementary Appendix D) at the beginning of training to determine how well they had retained key information from the 5 online learning modules. At the conclusion of the training, students were administered a post-training knowledge assessment which was identical to the pre-training questionnaire (Supplementary Appendix D). Students were not provided feedback on their score and an answer key was not provided to ensure that there were no confounding effects on knowledge assessment score outcomes.

Curriculum Evaluation

We evaluated the impact of the curriculum on students’ perceived confidence in the knowledge required to conduct whole blood transfusions before and after the didactic training using Likert-scale items and performance on the 10-question multiple choice knowledge test. In this analysis, these items were treated as interval scale variables with values ranging from 1 to 5. For all the statistics reported the larger values correspond to more desirable ratings. For example, the first question was “I can perform an emergency fresh whole blood transfusion safely without direct supervision or assistance from another medical provider.” The potential answer choices were “1—not confident at all, 2—slightly confident but still with major concerns, 3—neither, 4—fairly confident, 5—extremely confident.”

Data Analysis

Statistical analysis and graph generation were performed using Microsoft Excel and R-Studio. We conducted a 1-tailed paired t-test with a 95% confidence level to determine if there was an increase in scores following training. A 2-way ANOVA was performed to determine whether there was a difference in post-training scores based on branch of service and previous deployment status. Pairwise comparisons were conducted, and a Bonferroni correction was performed on the P-values. Results with a P-value less than .05 were considered significant. One star (*) corresponds to P <.05, two stars (**) correspond to P <.01, three stars (***) correspond to P <.001, and four stars (****) correspond to P <.0001. Scores from 2 USPHS students were omitted from branch-specific analysis because of insufficient sample size. Additionally, data points from 8 participants were omitted because of incomplete questionnaires yielding a final sample size of 157 students.

RESULTS

The perceived confidence of third-year medical students increased significantly after receiving the training, with the average confidence score increasing by 1.5 points (Fig. 1). The largest increase in confidence was found to be in the student’s ability to identify “red flags” when inspecting a unit of blood, which rose by 2.62 points (Table I). Similarly, student test scores also increased significantly, with the average score increasing by approximately 3 points, or 30% (Fig. 2). There was no significant difference in student confidence assessment or test scores based on branch of service; each branch showed a strong increase in scores following training (Fig. 3).

A total of 47 of these participants self-reported prior military service with an average length of 6.49 years and the average number of deployments reported was 2.33. Out of this sub-group, 4 participants reported an average number of 3 combat deployments. Additionally, 14 participants reported previous experience with EFWBT training in a field/training setting, MTF, or combat environment.

DISCUSSION

Our results suggest that the implementation of a novel and efficient EFWBT training curriculum is an effective method to improve knowledge in the foundational topics required by future military medical officers to safely and effectively perform EFWBT. The participants in our study demonstrated statistically significant improvement as indicated by improved scores on both the multiple-choice questions and on the self-reported questionnaire values. Evaluation of the change in confidence scores indicates that the EFWBT program administered in this study effectively improves student confidence in the evaluation and administration of EFWBT. The results indicate that students significantly improved confidence in the knowledge and skills required to conduct EFWBT in austere environments.

Although confidence is an important contributing factor in patient management, there are many factors to take into consideration when training medical students to safely and effectively perform medical treatments and procedures in real-world environments. However, a recent study from 2023 assessing the impact of high-fidelity medical simulation training demonstrated that, “increasing confidence in decision-making through education and training has the potential to improve the effectiveness of patient management. In addition, greater confidence may facilitate medical student decision-making processes through reduced stress and increased tolerance of uncertainty, especially when faced with immediately life-threatening patient problems.”¹⁹ Future military medical officers will be faced with complex decision-making related to overcoming the unique challenges inherent to conducting EFWBT in operational environments. Therefore, increased confidence in the knowledge required to conduct EFWBT in these environments offers a meaningful first step towards addressing current gaps in undergraduate medical education related to EFWBT training.

Although there was a statistically significant difference between pre- and post-assessment self-reported confidence scores of participants who had been deployed, this was most likely not because of previous deployment status. This finding is further supported by lack of statistically significant differences when comparing pre-assessment self-reported scores for those who had been deployed versus those who had not. The relatively small sample size of those who had been deployed (N = 18) may also have limited any meaningful statistical analysis. Similar results were noted for those who had received prior EFWBT training (N = 14) suggesting that EFWBT is a perishable skill that must be maintained through periodic training and reassessment.

Modernized combat casualty care in far-forward landscapes of war requires military medical officers to leverage capabilities that can deliver life-saving care at the point of injury, provide DCR in resource-limited environments, enable prolonged casualty care, and support long-distance en route care consistent with the demands of an all-domain battlespace against a near-peer competitor.⁵ Providing a structured, standardized, and efficient training curriculum like the one presented in our study early on in future military medical officer’s undergraduate medical education can help ensure that they are able to effectively treat our nation’s warfighters in future large-scale combat operations.

In addition to its potential to increase medical readiness, this training established a baseline knowledge and skill assessment in EFWBT which is of significant educational, medical, and operational importance. For example, the framework of this curriculum can potentially support periodic reassessment of an individual’s proficiency in EFWBT providing operational commanders and their unit’s senior medical officer with an effective tool to identify deficiencies in their medical personnel’s capabilities.

LIMITATIONS

Although the results of this study are promising, there are important limitations that should be noted. This study lacked a control group to serve as a comparison for our training group. Additionally, the practical applications were all performed on intravenous access trainers using simulated blood products. Intravenous access trainers are not representative of performing EFWBT on real patients and can induce training scars in understanding how to appropriately adjust the flow rate of the blood delivered, overcoming challenges in gaining intravenous access on a volume-depleted trauma patient, and appreciating the increased cognitive load in executing this skill in a simulated combat environment.

According to the JTS Fresh Whole Blood Transfusion CPG, there is no substitution for autologous transfusions in terms of training value for future clinicians and medics as this more realistically simulates real-world conditions and places increased cognitive and psychomotor demands on the student to gain intravenous access on a live patient, appropriately draw a unit of FWB, and re-administer that blood to the same patient ensuring safety and efficacy is maintained at all times.¹⁴ With a robust risk assessment and appropriately implemented controls, incorporation of both intravenous access and autologous transfusions to more accurately assess the efficacy of the training curriculum may be warranted.

FUTURE RESEARCH

Future research studies should explore training using both intravenous access and autologous transfusions to more accurately assess the efficacy of the training curriculum. Of utmost importance, follow-up evaluation is required to identify the rate of skill and knowledge degradation acquired during the EFWBT program to drive policy implementation outlining the appropriate frequency in skill re-assessment and sustainment training of EFWBT.

Additionally, DCR is an important skill that is traditionally utilized within the larger framework of team-based treatment of a critically injured trauma patient with the end goal to work synergistically with Damage Control Surgery to reduce patient morbidity and mortality.¹ Incorporation of autologous transfusions and assessment of EFWBT procedural skill proficiency should be incorporated into high-fidelity simulated TCCC patient scenarios to provide a more accurate assessment of the capability of medical providers in treating real-world casualties. Future research should also compare the performance of participants who received this training early in their undergraduate medical education, compared with military medical students who did not receive this training, to assess whether there is an effect on EFWBTs performance in either a training environment or clinical patient care.

CONCLUSION

Our study suggests that the implementation of streamlined EFWBT training curriculum into the undergraduate medical education of future military medical officers can improve their confidence in the knowledge required to successfully conduct an EFWBT.

ACKNOWLEDGMENTS

The authors would like to acknowledge the contributions of their colleagues Sherri Rudinsky, M.D., Cynthia Shen, D.O., Melissa Givens, M.D., the 75th Ranger Regiment, and the Navy Education and Training Office (NETO), 1st Marine Division.

INSTITUTIONAL REVIEW BOARD (HUMAN SUBJECTS)

This study was approved by the USU Institutional Review Board (IRB) (DBS.2022.362).

INSTITUTIONAL ANIMAL CARE AND USE COMMITTEE (IACUC)

Not applicable.

INDIVIDUAL AUTHOR CONTRIBUTION STATEMENT

KJM, SW, ZLB, JPC, JTS, and RC designed this study. KJM, SW, ZLB, JPC, JTS, and RC collected the data. KJM and DW analyzed the data. KJM, SW, DW, and RC drafted the manuscript. KJM, SW, ZLB, JPC, JTS, DW, and RC reviewed and approved the final manuscript.

INSTITUTIONAL CLEARANCE

Institutional clearance approved.

CLINICAL TRIAL REGISTRATION

None declared.

SUPPLEMENTARY MATERIAL

SUPPLEMENTARY MATERIAL is available at Military Medicine online.

FUNDING

FY 2023 Uniformed Services University Intramural Award.

CONFLICT OF INTEREST STATEMENT

None declared.

DATA AVAILABILITY

The data that support the findings of this study are available from the corresponding author. All data are freely accessible and will be provided upon request.

REFERENCES

Author notes