An Analysis of Adherence to Tactical Combat Casualty Care Guidelines for the Administration of Tranexamic Acid

Tranexamic acid as an adjunct to resuscitative endovascular balloon occlusion of the aorta does not worsen outcomes in a porcine model of hemorrhage

Background

Non-compressible torso hemorrhage (NCTH) represents a leading cause of preventable mortality in trauma. Resuscitative endovascular balloon occlusion of the aorta (REBOA) stabilizes NCTH but may predispose patients to thrombus generation. REBOA must therefore be prospectively evaluated for coagulation risks with concomitant usage of anti-fibrinolytic tranexamic acid (TXA). Using a porcine model of hemorrhage, it was hypothesized that TXA with REBOA would worsen coagulation outcomes and organ damage.

Materials and methods

Thirty-two male Yorkshire swine underwent 30% blood volume hemorrhage with randomization to vehicle control (VC; normal saline), VC+REBOA, TXA, or TXA+REBOA. At T0, animals received 10 mL/minute of group-specific infusion (GSI) followed at T10 by 500 mL of whole blood (WB), second GSI at 13 mL/hour, and Zone 1 REBOA inflation in REBOA groups. At T40, REBOA was deflated, with additional 500 mL WB, and continuation of GSI for 3 hours. Physiological, coagulation, and inflammatory parameters were measured throughout the protocol, with postmortem histopathology.

Results

After REBOA deflation at T40, lactate was significantly higher for the REBOA groups versus the non-REBOA groups, and pH, bicarbonate, and base excess were all significantly lower than the non-REBOA groups. There were no significant differences observed between groups in coagulation, inflammatory, metabolic, or histopathologic parameters.

Conclusions

Administration of TXA with REBOA did not cause more deleterious coagulation outcomes. All significant changes were expected results of REBOA ischemia, and not attributable to TXA treatment. This suggests NCTH can safely be treated with both hemorrhage control methods without exacerbating clotting outcomes.

Level of evidence

Not applicable-basic animal research.

Retrospective analysis of tranexamic acid administration in French war-wounded between October 2016 and September 2020

INTRODUCTION

Since 2013, the French Army Health Service, in agreement with international experts, has recommended the administration of 1 g of tranexamic acid (TXA) in trauma patients in haemorrhagic shock or at risk of bleeding within 3 hours of the trauma.

METHODS

The aim of this analysis was to describe the administration of TXA in French military personnel wounded during military operations in the Sahelo-Sahelian band between October 2016 and September 2020. Data were collected from forward health records and hospital data from the French hospital where the casualty was finally evacuated. Underuse of TXA was defined as the lack of administration in casualties who had received a blood transfusion with one or more of red blood cells, low-titre whole blood or French lyophilised plasma within the first 24 hours of injury and overuse as its administration in the non-transfused casualty.

RESULTS

Of the 76 patients included, 75 were men with an average age of 28 years. Five patients died during their management. 19 patients received TXA (25%) and 16 patients were transfused (21%). Underuse of TXA occurred in 3 of the 16 patients (18.8%) transfused. Overuse occurred in 6 of 60 (10%) non-transfused patients.

CONCLUSION

The analysis found an important underuse of TXA (almost 20%) and highlighted the need for optimising the prehospital clinical practice guidelines to aid prehospital medical practitioners more accurately in administering TXA to casualties that will require blood products.

Characterising practice patterns of human derived, lyophilized coagulation concentrates within the trauma quality improvement program registry

OBJECTIVES

We seek to describe the current practice pattern use of prothrombin complex concentrate (PCC) and fibrinogen concentrate (FC) in trauma patients.

BACKGROUND

Trauma-induced coagulopathy (TIC) and endotheliopathy of trauma (EOT) contribute significantly to mortality from traumatic haemorrhage. FC, and 4-factor PCC are potential treatments for EOT and TIC, respectively.

MATERIALS AND METHODS

We obtained data from the Trauma Quality Improvement Program (TQIP) registry and identified patients who received either PCC or FC using procedural codes. We used descriptive statistics to characterise practice patterns of these products.

RESULTS

There were 6 714 002 total encounters within the TQIP from 2017 to 2022, of which 10 589 received PCC and 3009 received FC. Of the recipients, there were 35 that received both products. There were 44 that received both. The median age of PCC recipients was 77 (69-84) with 19 patients <15 years of age with the youngest being 2 years of age. There was a general upward trend in the number of facilities with documented use of PCC: 155/744, 168/766, 189/764, 206/780, 234/795, and 235/816, respectively. The median age of FC recipients was 57 (32-75) with 48 patients <15 years of age with the youngest being 1 year of age. There was a minor downward trend in the number of facilities that had documented use of FC: 55, 44, 39, 32, 38 and 40.

CONCLUSIONS

The administration of PCC and FC remains uncommon, although there appears to be an upward trend of PCC use. Most PCC use appeared to be for anticoagulation reversal in the setting of head trauma. Data guiding the use of these products are necessary as these products become more recognised as adjuncts to traumatic haemorrhage control.

Intravenous Versus Intraosseous Use of Tranexamic Acid in Patients With Traumatic Brain Injury

INTRODUCTION

Tranexamic acid (TXA) is an antifibrinolytic drug that has been demonstrated to reduce head injury-related mortality when given within 2 h of injury in patients with traumatic brain injury and intracranial hemorrhage. It is usually administered via intravenous (IV) access, which can be difficult to obtain in prehospital and austere settings. Intraosseous (IO) access is fast and offers an alternative when IV access proves challenging; however, TXA administration via IO access has never been studied in humans. We sought to determine if the total drug exposure of TXA given in the prehospital setting in patients with moderate or severe brain injury differs based on route of administration.

METHODS

We performed a retrospective analysis of prospectively collected data from the prehospital TXA for traumatic brain injury trial (NCT01990768). Participants who received TXA via IO administration were compared to those who received TXA via IV administration and stratified by renal function category based on the Kidney Disease Improving Global Outcomes criteria. The area under the plasma drug concentration-time curve (AUC) was calculated using the trapezoidal rule (Phoenix WinNonlin 8.3, Certara, Princeton NJ) to obtain total drug exposure. The inverse variance method was used to combine observations within strata and calculate mean differences.

RESULTS

Of the 966 participants enrolled in the trial, 345 participants received a 2-g TXA prehospital bolus (11 IO, 334 IV); 312 participants received a 1-g TXA prehospital bolus followed by a 1-g TXA infusion in-hospital over 8 h (13 IO, 299 IV). After exclusion because of missing data and extreme estimated AUC, 233 IV and eight IO participants in the 2-g bolus arm and 152 IV and eight IO participants in the 1-g bolus 1-g infusion arm remained. Participants did not differ by age, sex, race, ethnicity, body mass index, serum creatinine, estimated glomerular filtration rate, or clot lysis at 30 min on thromboelastography. No difference in the mean AUCs were observed between IV and IO for either the 2-g bolus group (-2.6 μ g/mL/h [IO] compared to IV, 95% confidence interval: -28.4 to 23.3 μ g/mL/h) or the 1-g bolus/1-g infusion group (-13.0 μ g/mL/h [IO] compared to IV, 95% confidence interval: -236.2 to 210.3 μ g/mL/h).

CONCLUSIONS

These preliminary data suggest that the administration of TXA via IO and IV routes may result in similar total drug exposure. Further studies incorporating larger numbers with clinical outcomes are needed to confirm this finding.

Lessons learned from the war in Ukraine for the anesthesiologist and intensivist: A scoping review

BACKGROUND

The war in Ukraine provides purposefully anesthesiologists and intensivists with important data for improving the management of trauma patients. This scoping review aims to investigate the specific management of war-related trauma patients, during the war in Ukraine, through an objective and comprehensive analysis.

METHODS

A comprehensive search of the Embase, Medline, and Open Grey databases from 2014 to February 2024 yielded studies focusing on anesthesia and surgery. These studies were assessed by PRISMA and STROBE criteria and needed to discuss anesthesiology and surgical procedures.

RESULTS

Of the 519 studies identified, 21 were included, with a low overall level of evidence. The studies covered 11,622 patients and 2470 surgical procedures. Most patients were Ukrainian men, 25-63 years old, who had sustained severe injuries from high-energy weapons, such as multiple rocket systems and combat drones. These injuries included major abdominal, facial, and extremity traumas. The surgical procedures varied from initial debridement to complex reconstructions. Anesthesia management faced significant challenges, including resource scarcity and the need for quick adaptability. Evacuations of casualties were lengthy, complex, and often involved rail transportation. Hemorrhage control with tourniquets was critical but associated with many complications. The very frequent presence of multi-resistant organisms required dedicated preventive measures and appropriated treatments. The need for qualified human resources underscored the importance of civilian-military cooperation.

CONCLUSION

This scoping review provides original and relevant insights on the lessons learned from the ongoing war in Ukraine, which could be useful for anesthesiologists and intensivists.

Pharmacokinetics of Tranexamic Acid (TXA) Delivered by Expeditious Routes in a Swine Model of Polytrauma and Hemorrhagic Shock

OBJECTIVE

Hemorrhage is the leading cause of preventable death in civilian trauma centers and on the battlefield. One of the emerging treatment options for hemorrhage in austere environments is tranexamic acid (TXA). However, the landscape is not amenable to the current delivery standard. This study compared the pharmacokinetics of TXA via a standard 10-minute intravenous infusion (IV infusion), intravenous rapid push over 10 s (IV push), and intramuscular injection (IM) in a swine polytrauma and hemorrhagic shock model (trauma group) compared to uninjured controls (control group).

METHODS

Thirty swine were randomized to the trauma or control group. Following anesthesia, the trauma group experienced a simulated blast injury and 40% controlled hemorrhage. Subjects in both groups were then randomized to receive 1 g/10 mL TXA via IV infusion, IV push, or IM. Animals were monitored for four hours with serial blood sampling. Serum TXA concentrations were measured by liquid chromatography with tandem mass spectrometry (LC-MS/MS) and analyzed.

RESULTS

The time to maximum TXA concentration (Tmax) was not affected by trauma in IV infusion or IV push, but was affected in the IM administration with Tmax significantly slower than the control group (p = 0.016). The minimum effective serum concentration of TXA (Ceff, 10 µg/mL) was reached in less than one minute with IV infusion and instantaneously with IV push. Despite lower bioavailability, the time to reach Ceff (Teff) was achieved via IM administration in less than 10 min for both groups (6.4 min trauma vs. 2.1 min control).

CONCLUSIONS

In austere prehospital environments, an alternative to intravenous infusion of a life-saving medication is desired. Administration of TXA via all three methods reached the level needed to cause substantial inhibition of fibrinolysis within 10 min. The IV push method showed similar pharmacokinetics to IV infusion of TXA but can be delivered quickly without sacrificing an access site for 10 min.

A survey of low titer O whole blood use within the trauma quality improvement program registry

INTRODUCTION

The use of low titer O whole blood (LTOWB) has expanded although it remains unclear how many civilian trauma centers are using LTOWB.

METHODS

We analyzed data on civilian LTOWB recipients in the American College of Surgeons Trauma Quality Improvement Program (TQIP) database 2020-2021. Unique facility keys were used to determine the number of centers that used LTOWB in that period.

RESULTS

A total of 16,603 patients received LTOWB in the TQIP database between 2020 and 2021; 6600 in 2020, and 10,003 in 2021. The total number of facilities that reported LTOWB use went from 287/779 (37%) in 2020 to 302/795 (38%) in 2021. Between 2020 and 2021, among all level 1-3 designated trauma facilities that report to TQIP LTOWB use increased at level-1 centers (118 to 129), and level-2 centers (81 to 86), but decreased in level-3 facilities (9 to 4). Among pediatric and dual pediatric-adult designated hospitals there was a decrease in the number of pediatric level-1 centers (29 to 28) capable of administering LTOWB. Among centers with either single or dual level-1 trauma center designation with adult centers, the number that administered LTOWB to injured pediatric patients also decreased from 17 to 10, respectively.

CONCLUSIONS

There was an increase in the number of facilities transfusing LTOWB between 2020 and 2021. The use of LTOWB is underutilized in children at centers that have it available. These findings inform the expansion of LTOWB use in trauma.

Associations with Prehospital Antibiotic Receipt among Combat Casualties with Open Wounds: A Department of Defense Trauma Registry Study

INTRODUCTION

Current Tactical Combat Casualty Care (TCCC) guidelines recommend antibiotic administration for all open wounds to prevent infection. We identified associations between demographics, procedures, and medicines with the receipt of prehospital antibiotics among combat casualties.

MATERIALS AND METHODS

We used a series of emergency department procedure codes to identify adult subjects within the Department of Defense Trauma Registry from January 2007 to August 2016 who sustained open wounds. We compared demographics, procedures, and medicines administered among casualties receiving prehospital wound prophylaxis versus casualties not receiving antibiotic prophylaxis. We controlled for confounders with multivariable logistical regression.

RESULTS

We identified 18,366 encounters meeting inclusion criteria. Antibiotic recipients (n = 2384) were comparable to nonrecipients (n = 15,982) with regard to age and sex. Antibiotic recipients were more likely to sustain injuries from firearms and undergo all procedures examined related to hemorrhage control, airway management, pneumothorax treatment, and volume replacement except for intraosseous access. Antibiotic recipients were less likely to sustain injuries from explosives. Antibiotic recipients had a modestly higher survival than nonrecipients (97.4% versus 96.0%). Associations with prehospital antibiotic receipt in multivariable logistic regression included non-North Atlantic Treaty Organization military force affiliation (odds ratio (OR) 4.65, 95% CI, 1.0-20.8), tachycardia (OR 3.4, 95% CI, 1.1-10.5), intubation (OR 2.0, 95% CI, 1.1-3.8), and administration of tranexamic acid (OR 5.6, 95% CI, 1.2-26.5).

CONCLUSIONS

The proportion of combat casualties with open wounds receiving prehospital antibiotics was low despite published recommendations for early antibiotics in patients with open wounds. These findings highlight the ongoing need for additional educational and quality assurance initiatives to continue improving adherence to TCCC guidelines with regard to prehospital antibiotic administration. Future studies are necessary to determine reasons for suboptimal TCCC guideline compliance.

A Systematic Review of Tranexamic Acid-Associated Venous Thromboembolic Events in Combat Casualties and Considerations for Prolonged Field Care

INTRODUCTION

Tranexamic acid (TXA) is a standard component of Tactical Combat Casualty Care. Recent retrospective studies have shown that TXA use is associated with a higher rate of venous thromboembolic (VTE) events in combat-injured patients. We aim to determine if selective administration should be considered in the prolonged field care environment.

MATERIALS AND METHODS

We performed a systematic review using the 2020 Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines. Clinical trials and observational studies of combat casualties published between January 1, 1960, and June 20, 2022, were included. We analyzed survival and VTE outcomes in TXA recipients and non-recipients. We discussed the findings of each paper in the context of current and future combat environments.

RESULTS

Six articles met criteria for inclusion. Only one study was powered to report mortality data, and it demonstrated a 7-fold increase in survival in severely injured TXA recipients. All studies reported an increased risk of VTE in TXA recipients, which exceeded rates in civilian literature. However, five of the six studies used overlapping data from the same registry and were limited by a high rate of missingness in pertinent variables. No VTE-related deaths were identified.

CONCLUSIONS

There may be an increased risk of VTE in combat casualties that receive TXA; however, this risk must be considered in the context of improved survival and an absence of VTE-associated deaths. To optimize combat casualty care during prolonged field care, it will be essential to ensure the timely administration of VTE chemoprophylaxis as soon as the risk of significant hemorrhage permits.

Factors that influence the administration of tranexamic acid (TXA) to trauma patients in prehospital settings: a systematic review

OBJECTIVE

In the UK there are around 5400 deaths annually from injury. Tranexamic acid (TXA) prevents bleeding and has been shown to reduce trauma mortality. However, only 5% of UK major trauma patients who are at risk of haemorrhage receive prehospital TXA. This review aims to examine the evidence regarding factors influencing the prehospital administration of TXA to trauma patients.

DESIGN

Systematic literature review.

DATA SOURCES

AMED, CENTRAL, CINAHL, Cochrane Database of Systematic Reviews, Conference Proceedings Citation Index-Science, Embase and MEDLINE were searched from January 2010 to 2020; searches were updated in June 2022.

CLINICALTRIALS

gov and OpenGrey were also searched and forward and backwards citation chasing performed.

ELIGIBILITY CRITERIA

All primary research reporting factors influencing TXA administration to trauma patients in the prehospital setting was included.

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers performed the selection process, quality assessment and data extraction. Data were tabulated, grouped by setting and influencing factor and synthesised narratively.

RESULTS

Twenty papers (278 249 participants in total) were included in the final synthesis; 13 papers from civilian and 7 from military settings. Thirteen studies were rated as 'moderate' using the Effective Public Health Practice Project Quality Assessment Tool. Several common factors were identified: knowledge and skills; consequences and social influences; injury type (severity, injury site and mechanism); protocols; resources; priorities; patient age; patient sex.

CONCLUSIONS

This review highlights an absence of high-quality research. Preliminary evidence suggests a host of system and individual-level factors that may be important in determining whether TXA is administered to trauma patients in the prehospital setting.

FUNDING AND REGISTRATION

This review was supported by Research Capability Funding from the South Western Ambulance Service NHS Foundation Trust and the National Institute for Health Research Applied Research Collaboration South West Peninsula.

PROSPERO REGISTRATION NUMBER

CRD42020162943.

Impact of time and distance on outcomes following tourniquet use in civilian and military settings: A scoping review

BACKGROUND

The last two decades have seen the reintroduction of tourniquets into guidelines for the management of acute limb trauma requiring hemorrhage control. Evidence supporting tourniquet application has demonstrated low complication rates in modern military settings involving rapid evacuation timeframes. It is unclear how these findings translate to patients who have prolonged transport times from injury in rural settings. This scoping review investigates the relationship between time and distance on metabolic complications, limb salvage and mortality following tourniquet use in civilian and military settings.

METHODS

A systematic search strategy was conducted using PubMed, Embase, and SafetyLit databases. Study characteristics, setting, mechanism of injury, prehospital time, tourniquet time, distance, limb salvage, metabolic response, mortality, and tourniquet removal details were extracted from eligible studies. Descriptive statistics were recorded, and studies were grouped by ischemia time (< 2 h, 2-4 h, or > 4 h).

RESULTS

The search identified 3103 studies, from which 86 studies were included in this scoping review. Of the 86 studies, 55 studies were primarily in civilian environments and 32 were based in military settings. One study included both settings. Blast injury was the most common mechanism of injury sustained by patients in military settings (72.8% [5968/8200]) followed by penetrating injury (23.5% [1926/8200]). In contrast, in civilian settings penetrating injury was the most common mechanism (47.7% [1633/3426]) followed by blunt injury (36.4% [1246/3426]). Tourniquet time was reported in 66/86 studies. Tourniquet time over four hours was associated with reduced limb salvage rates (57.1%) and higher mortality rates (7.1%) compared with a tourniquet time of less than two hours. The overall limb salvage and mortality rates were 69.6% and 6.7% respectively. Metabolic outcomes were reported in 28/86 studies with smaller sample sizes and inconsistencies in which parameters were reported.

CONCLUSION

This scoping review presents literature describing comparatively safe tourniquet application when used for less than two hours duration. However, there is limited research describing prolonged tourniquet application or when used for protracted distances, such that the impact of tourniquet release time on metabolic outcomes and complications remains unclear. Prospective studies utilizing the development of an international database to provide this dataset is required.

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.

To Tranexamic Acid or Not to Tranexamic Acid? Accuracy of Antifibrinolytic Administration at Altitude

OBJECTIVE

Tranexamic acid (TXA) has demonstrated a reduction in all-cause mortality in trauma patients with hemorrhage. Administering TXA in the prehospital setting presents unique challenges because the identification of bleeding is based on clinical suspicion without advanced imaging or diagnostic tools. The objective of this study was to examine whether prehospital suspicion of bleeding is validated by in-hospital computed tomographic imaging and examination and to determine if patients received TXA in the absence of hemorrhage. The study was conducted at a level 1 trauma center supported by air medical transport services.

METHODS

This is a retrospective cohort study examining 88 trauma patients receiving prehospital TXA to treat suspected hemorrhage. Adult trauma patients who received TXA during the study period and were transported to our level 1 trauma center were included. A panel of trauma surgeons reviewed CT imaging and examination findings to retrospectively identify significant hemorrhage.

RESULTS

Forty-three percent of patients who received TXA during air medical transport did not have confirmed hemorrhage upon arrival.

CONCLUSION

TXA was given to a significant number of patients who did not have confirmed hemorrhage upon arrival. We recommend that institutions using TXA perform this internal validation to ensure they are accurately identifying hemorrhage in the prehospital setting.

Efficacy and safety of the second in-hospital dose of tranexamic acid after receiving the prehospital dose: double-blind randomized controlled clinical trial in a level 1 trauma center

Background

Prehospital administration of tranexamic acid (TXA) to injured patients is increasing worldwide. However, optimal TXA dose and need of a second infusion on hospital arrival remain undetermined. We investigated the efficacy and safety of the second in-hospital dose of TXA in injured patients receiving 1 g of TXA in the prehospital setting. We hypothesized that a second in-hospital dose of TXA improves survival of trauma patients.

Methods

A prospective, double-blind, placebo-controlled randomized, clinical trial included adult trauma patients receiving 1 g of TXA in the prehospital settings. Patients were then blindly randomized to Group I (second 1-g TXA) and Group II (placebo) on hospital arrival. The primary outcome was 24-h (early) and 28-day (late) mortality. Secondary outcomes were thromboembolic events, blood transfusions, hospital length of stay (HLOS) and organs failure (MOF).

Results

A total of 220 patients were enrolled, 110 in each group. The TXA and placebo groups had a similar early [OR 1.000 (0.062–16.192); p = 0.47] and late mortality [OR 0.476 (95% CI 0.157–1.442), p = 0.18].The cause of death (n = 15) was traumatic brain injury (TBI) in 12 patients and MOF in 3 patients. The need for blood transfusions in the first 24 h, number of transfused blood units, HLOS, thromboembolic events and multiorgan failure were comparable in the TXA and placebo groups. In seriously injured patients (injury severity score > 24), the MTP activation was higher in the placebo group (31.3% vs 11.10%, p = 0.13), whereas pulmonary embolism (6.9% vs 2.9%, p = 0.44) and late mortality (27.6% vs 14.3%, p = 0.17) were higher in the TXA group but did not reach statistical significance.

Conclusion

The second TXA dose did not change the mortality rate, need for blood transfusion, thromboembolic complications, organ failure and HLOS compared to a single prehospital dose and thus its routine administration should be revisited in larger and multicenter studies.

Trial registration

ClinicalTrials.gov Identifier: NCT03846973.

Barriers and facilitators to the administration of prehospital tranexamic acid: a paramedic interview study using the theoretical domains framework

BACKGROUND

Tranexamic acid (TXA) is an antifibrinolytic drug used to prevent bleeding. It was introduced as an intervention for post-traumatic haemorrhage across emergency medical services (EMS) in the UK during 2012. However, despite strong evidence of effectiveness, prehospital TXA administration rates are low. This study used the theoretical domains framework (TDF) to identify barriers and facilitators to the administration of TXA to trauma patients by EMS providers (paramedics) in the UK.

METHODS

Interviews were completed with 18 UK paramedics from a single EMS provider organisation. A convenience sampling approach was used, and interviews continued until thematic saturation was reached. Semistructured telephone interviews explored paramedics' experiences of administering TXA to trauma patients, including identifying whether or not patients were at risk of bleeding. Data were analysed inductively using thematic analysis (stage 1). Themes were mapped to the theoretical domains of the TDF to identify behavioural theory-derived barriers and facilitators to the administration of TXA to trauma patients (stage 2). Belief statements were identified and assessed for importance according to prevalence, discordance and evidence base (stage 3).

RESULTS

Barriers and facilitators to paramedics' administration of TXA to trauma patients were represented by 11 of the 14 domains of the TDF. Important barriers included a lack of knowledge and experience with TXA (Domain: Knowledge and Skills), confusion and restrictions relating to the guidelines for TXA administration (Domain: Social/professional role and identity), a lack of resources (Domain: Environmental context and resources) and difficulty in identifying patients at risk of bleeding (Domain: Memory, attention and decision processes).

CONCLUSIONS

This study presents a behavioural theory-based approach to identifying barriers and facilitators to the prehospital administration of TXA to trauma patients in the UK. It identifies multiple influencing factors that may serve as a basis for developing an intervention to increase prehospital administration of TXA.

An Analysis of 13 Years of Prehospital Combat Casualty Care: Implications for Maintaining a Ready Medical Force

Background: Most potentially preventable deaths occur in the prehospital setting before reaching a military treatment facility with surgical capabilities. Thus, optimizing the care we deliver in the prehospital combat setting represents a ripe target for reducing mortality. We sought to analyze prehospital data within the Department of Defense Trauma Registry (DODTR). Materials and methods: We requested all encounters with any prehospital activity (e.g., interventions, transportation, vital signs) documented within the DODTR from January 2007 to March 2020 along with all hospital-based data that was available. We excluded from our search casualties that had no prehospital activity documented. Results: There were 28,950 encounters that met inclusion criteria. Of these, 25,897 (89.5%) were adults and 3053 were children (10.5%). There was a steady decline in the number of casualties encountered with the most notable decline occurring in 2014. U.S. military casualties comprised the largest proportion (n = 10,182) of subjects followed by host nation civilians (n = 9637). The median age was 24 years (interquartile range/IQR 21-29). Most were battle injuries (78.6%) and part of Operation ENDURING FREEDOM (61.8%) and Operation IRAQI FREEDOM (24.4%). Most sustained injuries from explosives (52.1%) followed by firearms (28.1%), with serious injury to the extremities (24.9%) occurring most frequently. The median injury severity score was 9 (IQR 4-16) with most surviving to discharge (95.0%). A minority had a documented medic or combat lifesaver (27.9%) in their chain of care, nor did they pass through an aid station (3.0%). Air evacuation predominated (77.9%). Conclusions: Within our dataset, the deployed U.S. military medical system provided prehospital medical care to at least 28,950 combat casualties consisting mostly of U.S. military personnel and host nation civilian care. There was a rapid decline in combat casualty volumes since 2014, however, on a per-encounter basis there was no apparent drop in procedural volume.

Tranexamic Acid During Prehospital Transport in Patients at Risk for Hemorrhage After Injury: A Double-blind, Placebo-Controlled, Randomized Clinical Trial

IMPORTANCE

In-hospital administration of tranexamic acid after injury improves outcomes in patients at risk for hemorrhage. Data demonstrating the benefit and safety of the pragmatic use of tranexamic acid in the prehospital phase of care are lacking for these patients.

OBJECTIVE

To assess the effectiveness and safety of tranexamic acid administered before hospitalization compared with placebo in injured patients at risk for hemorrhage.

DESIGN, SETTING, AND PARTICIPANTS

This pragmatic, phase 3, multicenter, double-blind, placebo-controlled, superiority randomized clinical trial included injured patients with prehospital hypotension (systolic blood pressure ≤90 mm Hg) or tachycardia (heart rate ≥110/min) before arrival at 1 of 4 US level 1 trauma centers, within an estimated 2 hours of injury, from May 1, 2015, through October 31, 2019.

INTERVENTIONS

Patients received 1 g of tranexamic acid before hospitalization (447 patients) or placebo (456 patients) infused for 10 minutes in 100 mL of saline. The randomization scheme used prehospital and in-hospital phase assignments, and patients administered tranexamic acid were allocated to abbreviated, standard, and repeat bolus dosing regimens on trauma center arrival.

MAIN OUTCOMES AND MEASURES

The primary outcome was 30-day all-cause mortality.

RESULTS

In all, 927 patients (mean [SD] age, 42 [18] years; 686 [74.0%] male) were eligible for prehospital enrollment (460 randomized to tranexamic acid intervention; 467 to placebo intervention). After exclusions, the intention-to-treat study cohort comprised 903 patients: 447 in the tranexamic acid arm and 456 in the placebo arm. Mortality at 30 days was 8.1% in patients receiving tranexamic acid compared with 9.9% in patients receiving placebo (difference, -1.8%; 95% CI, -5.6% to 1.9%; P = .17). Results of Cox proportional hazards regression analysis, accounting for site, verified that randomization to tranexamic acid was not associated with a significant reduction in 30-day mortality (hazard ratio, 0.81; 95% CI, 0.59-1.11, P = .18). Prespecified dosing regimens and post-hoc subgroup analyses found that prehospital tranexamic acid were associated with significantly lower 30-day mortality. When comparing tranexamic acid effect stratified by time to treatment and qualifying shock severity in a post hoc comparison, 30-day mortality was lower when tranexamic acid was administered within 1 hour of injury (4.6% vs 7.6%; difference, -3.0%; 95% CI, -5.7% to -0.3%; P < .002). Patients with severe shock (systolic blood pressure ≤70 mm Hg) who received tranexamic acid demonstrated lower 30-day mortality compared with placebo (18.5% vs 35.5%; difference, -17%; 95% CI, -25.8% to -8.1%; P < .003).

CONCLUSIONS AND RELEVANCE

In injured patients at risk for hemorrhage, tranexamic acid administered before hospitalization did not result in significantly lower 30-day mortality. The prehospital administration of tranexamic acid after injury did not result in a higher incidence of thrombotic complications or adverse events. Tranexamic acid given to injured patients at risk for hemorrhage in the prehospital setting is safe and associated with survival benefit in specific subgroups of patients.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02086500.