Integrated military and civilian partnerships are necessary for effective trauma-related training and skills sustainment during the inter-war period. Lee JJ, Hall AB, Carr MJ, MacDonald AG, Edson TD, Tadlock MD. J Trauma Acute Care Surg. 2022 Apr 1;92(4):e57-e76.
Recognizing a gap in knowledge and skills required for combat trauma surgical care since the 1990s, The National defense Authorization Act created funding for integrated training programs incorporating military and civilian trauma centers to ensure military medical readiness. Military Civilian partnerships (MCPs) are now considered integral to preparing military providers for combat casualty care and continue to be required as the primary means to combat the ‘peacetime effect.’ The ‘peacetime effect’ refers to the erosion of military combat relevant skills due to the drawdown of combat operations and limited military treatment facility combat relevant skills sustainment opportunities. Utilizing a broad literature-based search from 1980-2000, 866 articles relating to the topic areas were screened, 153 underwent full text review, and 61 articles ultimately met inclusion criteria and were evaluated. Concepts of the MCP, different MCP types and opportunities are described, and best practices in MCP delivery are suggested.
Five primary types of MCPs are described. “Skills Sustainment” referring to an MCP where military providers maintain their skillset through skills sustainment experiences at regular intervals in a civilian trauma center. “Just-In-Time Training” where a trauma team can receive trauma-specific training and exposure to clinical trauma care at a civilian trauma center just prior to deployment. “Strategic” referring to Military and Civilian information and education exchange, opportunity building and policy creation. “Integrated” referring to embedded military physicians at level 1 trauma centers functioning as staff, often with integrated GME programs. Finally, “Mentorship” referring to a senior civilian expert providing mentorship to junior military colleagues, such as a visiting surgeon program. Objective evaluation of programs and ‘outcomes’ of programs are difficult to quantify, with most reviews relating to case numbers, operative density (procedures per days worked), and qualitative review. All quantitative and qualitative metrics related to these partnerships showed improvement across all MCP model types (i.e., all MCP types showed increased trauma case volume and density and noted training to be beneficial to readiness as compared to the MTF experience). Despite the overall level of evidence being low, and that no direct link between skills maintenance and retention can be proven, most outcomes-related data indicates that both civilian and military MCP improve combat casualty care readiness. This was particularly true for teams who do not perform trauma-related care during their regular clinical practice. In the absence of integrating MTF into regional or national trauma systems, the best option for skills sustainment appears to be embedded teams in civilian trauma centers full time, or use of regional partnerships allowing the practice of relevant care at regular intervals. Not surprisingly, the available evidence suggests that skill sustainment is best accomplished through continual practice of relevant skills, and multiple efforts are underway to further expand MCP opportunities.
Prehospital whole blood reduces early mortality in patients with hemorrhagic shock. Braverman MA, Smith A, Pokorny D, Axtman B, Shahan CP, Barry L, Corral H, Jonas RB, Shiels M, Schaefer R, Epley E, Winckler C, Waltman E, Eastridge BJ, Nicholson SE, Stewart RM, Jenkins DH. Transfusion. 2021 Jul;61 Suppl 1:S15-S21.
Reintroduced and popularized during recent military conflicts, resuscitation with whole blood is practiced in all phases of care in the military environment, with the greatest benefit being seen closest to the point of injury. Whole blood has become a first-line agent in hemorrhagic shock resuscitation. Whole blood has also experienced a resurgence of interest in the civilian setting with the proposed advantages of lower transfusion volume, ease of administration compared to component therapy (defined as a 1:1:1 ratio of packed red blood cells, fresh frozen plasma, and platelets), and exposure to multiple donors. Few studies have specifically addressed the use of whole blood in the civilian prehospital setting. This study capitalized on the unique capabilities of STRAC (Southwest Texas Regional Advisory Council), where whole blood has been used in the prehospital civilian setting since 2018, including flight and ground prehospital assets. Under IRB approval, registry data- including patients receiving prehospital whole blood (PHT) vs. no transfusion (NT)- from 2015-2019 was analyzed. Primary data outcomes included vital signs (HR, SBP, and Shock index), mortality (ED, 6- and 12- hour time points), and massive transfusion needs. Use of prehospital WH was based on previously published protocol, subgroup analysis on prehospital cardiac arrest was also analyzed. Finally, a propensity-matched analysis comparing PHT and NT was performed for patients in shock.
During the study period, 803 patients underwent transfusion, 538 patients remained for analysis after exclusions. Of these, 107 patients (19.8%) received PHT with 431 patients in the NT group. 265 excluded patients were due to lack of complete data. The PHT group were more likely male (84.1% vs. 69.4%, p = .002), with more penetrating trauma (63.6% vs. 27.6%, p < .001), and lower median ISS (17 vs. 22, p = .004) (Table 1). PHT patients had a lower SBP, higher HR, and higher SI compared to NT patients, and improvement in SI (delta SI) from nadir to arrival was greatest in the PHT group compared to the NT group. Mortality between the two groups at all time points was not different. PHT and NT groups were similar regarding incidence of massive transfusion. PHT patients required less blood product volume in the ED but ultimately received the same total transfusion volume over total hospital LOS. The subgroup of cardiac arrest has equivalent mortality. With propensity matching, patients undergoing PHT had a lower median HR, a trend toward a higher median SBP and a greater improvement in median SI, with reduced ED mortality in the PHT group. Overall, though limited in sample size, this retrospective study illustrates the potential impact of prehospital transfusion with LTOWB in severely injured patients with hemorrhagic shock. In examining all patients transfused, despite a higher degree of shock on arrival the PHT group exhibited a greater improvement in SI and a resultant reduction in transfusion. PHT demonstrated a reduction in trauma bay mortality short term, albeit with no observed benefit in long-term mortality outcomes. Authors call for a prospective, multi-institutional study to better define practice.
Systematic review of temporary intravascular shunt use in military and civilian extremity trauma. Laverty RB, Treffalls RN, Kauvar DS. J Trauma Acute Care Surg. 2022 Jan 1;92(1):232-238.
The use of temporary intravascular shunting (TIVS) has continued to increase in both the military and civilian trauma setting. TIVS offers the advantage of temporary restoration of blood flow to injured extremities, allowing focus to shift to correcting physiology and to other injuries. In addition, it re-establishes blood flow within an ischemic window which helps in planning eventual limb salvage procedures, providing a good option for far-forward military surgical teams or rural medical centers, who would eventually transfer the patient to a higher level of care. Multiple studies from various centers have been published outlining the benefits of intravascular shunts. The aim of the study by Laverty and colleagues was to consolidate and analyze the information presented across these multiple studies to better understand TIVS use across military and civilian populations. By compiling this data, the goal was to categorize trends in intravascular shunt use as well as identify any gaps for potential future research.
This systematic review examined 21 studies out of 138 cases screened from EMBASE, MEDLINE, EBSCO, and Cochrane databases investigating TIVS. These articles included reports from one or more civilian trauma centers, analysis of databases (NTDP and PROOVIT), reports from military field hospitals, as well as military casualty care databases. This review included a mix of retrospective and prospective studies from the United States and internationally, as well as military articles, which allowed the group to consider data in patients with higher injury severity scores and with military-unique blast injuries.
In reviewing this data, the authors found that TIVS seemed to be more commonly used in the military population than in the civilian population (1.3 shunts per patient vs 1.1 shunts per patient). Shunts were more commonly used in the setting of penetrating injury of the lower extremity than blunt injury. The mean injury severity score was higher within the military population, with this population also having a high percentage of explosive injury in comparison with a civilian population. Arterial shunts were more frequently used as compared to venous shunts. The most common reason for TIVS was for damage control, with staged fixation of an orthopedic injury being the second most common use. Only a few studies compared TIVS to patients without shunts. In these specific studies, the use of shunts decreased the time to reperfusion and the rate of compartment syndrome, though there did not appear to be a significant difference in limb salvage rates.
Although some conclusions could be drawn from this review, it also revealed some continued areas of controversies with shunt use. The effect of dwell time on thrombosis or whether anticoagulation has any effect on successful use were two questions that were not able to be adequately addressed. In addition, there was no standardization of data collection, creating a paucity in comparative data. This analysis exposes these deficiencies, suggesting that a prospective study with standardized collection criteria may be the next step in better understanding TIVS and their applications in both civilian and military trauma.
Whole blood at the tip of the spear: A retrospective cohort analysis of warm fresh whole blood resuscitation versus component therapy in severely injured combat casualties. Gurney JM, Staudt AM, Del Junco DJ, Shackelford SA, Mann-Salinas EA, Cap AP, Spinella PC, Martin MJ. Surgery. 2022 Feb;171(2):518-525.
Hemorrhage continues to be the leading causes of death in trauma for military populations. Therefore, it is not surprising that a significant amount of research has been performed on the most effective transfusion strategies to decrease mortality from hemorrhage. It is well known that quick access to blood products improves survival in combat casualties. Earlier studies have explored the optimal ratio of blood product transfusions. Warm Fresh Whole Blood (WFWB) resuscitation is a method that has been employed in the military setting, as this is one of the easiest forms of blood to access in austere environments through “walking blood banks.” Previous observational studies from earlier in the wars in Iraq and Afghanistan using WFWB showed promise, but these were very broad and did not take into account variability of injury or physiologic severity. After retrospectively reviewing over 10,000 units of WFWB transfused in combat casualties in the recent conflicts, the current authors identified a survival advantage. However, the authors recognized shortfalls with their previous review and, thus, aimed to perform a secondary analysis of these data by adjusting for potential time-dependency bias (so called immortal time bias) using advanced statistical methods.
The study was a retrospective cohort study using data obtained from Role 2 military treatment facilities (MTFs) abroad and stored in the Joint Trauma System database. Five characteristics (injury type, patient affiliation, tourniquet use, pre-hospital blood transfusion, hourly rate of transfusion) were used to match patients who received WFWB with those who received other blood component therapy, but not WFWB. Patients who were not able to be matched were excluded from the study. The primary outcome was mortality at 6-hours after time of injury. Secondary outcomes of 6-hour mortality incorporating additional inclusion criteria (injury severity score, maximum abbreviated injury scale, admission base deficit, age, gender, shock, and time from injury to Role 2) and 6-hour mortality with associated head injury were also explored using the same set of patients. 1,105 patients met the eligibility criteria and were frequency matched with each other for analysis using logistic regression and Cox proportional hazards modeling. Though the raw number of patients receiving WFWB was significantly lower than those who did not receive WFWB, the frequency matching allowed for a fair comparison. It was found that receipt of WFWB was associated with significantly lower 6-hour mortality relative to the non WFWB patients. Secondary analysis, which included the additional factors and the presence of severe head injury also showed a stronger association of reduced mortality in WFWB patients.
Overall, this study suggests that the type of blood product being transfused is just as important as the timing of delivering the transfusion. This was a large study with a robust, military specific data set to pull from, which used a very systematic approach to collect and analyze the data. It also suggests that WFWB contributes to reduced mortality in combat trauma patients, which offers a logistical advantage in a military population. It is important to note that this study did include a mix of US and foreign nationals, which was the reason for the 6-hour window. This was a reasonable, clinically relevant time frame, but long-term data was unable to be analyzed. There are also some associated limitations regarding the collection of timing and other data in austere environments, and it was noted that some conclusions were made relying on the authors own combat experience. However, even including these limitations, this study highlights the utility of WFWB in resuscitative pathways, paving the way for further investigation regarding the benefits of WFWB.