Effect of treatment delay on the effectiveness and safety of antifibrinolytics in acute severe haemorrhage: a meta-analysis of individual patient-level data from 40 138 bleeding patients

Impact of time to start of tranexamic acid treatment on rebleed risk and outcome in aneurysmal subarachnoid hemorrhage

INTRODUCTION

The ULTRA-trial investigated effectiveness of ultra-early administration of tranexamic acid (TXA) in subarachnoid hemorrhage (SAH) and showed that TXA reduces the risk of rebleeding without concurrent improvement in clinical outcome. Previous trials in bleeding conditions, distinct from SAH, have shown that time to start of antifibrinolytic treatment influences outcome. This post-hoc analysis of the ULTRA-trial investigates whether the interval between hemorrhage and start of TXA impacts the effect of TXA on rebleeding and functional outcome following aneurysmal SAH.

PATIENTS AND METHODS

A post-hoc comparative analysis was conducted between aneurysmal SAH patients of the ULTRA-trial, receiving TXA and usual care to those receiving usual care only. We assessed confounders, hazard ratio (HR) of rebleeding and odds ratio (OR) of good outcome (modified Rankin Scale 0-3) at 6 months, and investigated the impact of time between hemorrhage and start of TXA on the treatment effect, stratified into time categories (0-3, 3-6 and >6 h).

RESULTS

Sixty-four of 394 patients (16.2%) in the TXA group experienced a rebleeding, compared to 83 of 413 patients (19.9%) with usual care only (HR 0.86, 95% confidence interval (CI): 0.62-1.19). Time to start of TXA modifies the effect of TXA on rebleeding rate (p < 0.001), with a clinically non-relevant reduction observed only when TXA was initiated after 6 h (absolute rate reduction 1.4%). Tranexamic acid treatment showed no effect on good outcome (OR 0.96, 95% CI: 0.72-1.27) with no evidence of effect modification on the time to start of TXA (p = 0.53).

DISCUSSION AND CONCLUSIONS

This study suggests that the effect of TXA on rebleeding is modified by time to treatment, providing a protective, albeit clinically non-relevant, effect only when started after 6 h. No difference in functional outcome was seen. Routine TXA treatment in the aneurysmal SAH population, even within a specified time frame, is not recommended to improve functional outcome.

Should soldiers take oral tranexamic acid before going into battle?

ABSTRACT

Tranexamic acid is an inexpensive antifibrinolytic treatment that reduces morbidity and mortality in civilian and military trauma patients. It must be administered within 3 hours of the injury, and its efficacy is greater the earlier it is given. It is already used preventively in the civilian environment in a number of indications to reduce bleeding and bleeding-related mortality. We wondered about the potential benefits of preventive oral administration of tranexamic acid prior to an assault for military personnel with a potential risk of injury.

Evaluation of the prehospital administration of tranexamic acid for injured patients: a state-wide observational study with sex and age-disaggregated analysis

BACKGROUND

Tranexamic acid (TXA) decreases mortality in injured patients and should be administered as soon as possible. Despite international guidelines recommending TXA in the prehospital setting, its use remains low. The aim of this study was to assess the prehospital administration of TXA for injured patients in a Swiss region.

METHODS

We conducted a retrospective observational study in Switzerland between 2018 and 2021. Inclusion criteria were injured patients ≥18 years for whom an ambulance or helicopter was dispatched. The exclusion criterion was minor injury defined by a National Advisory Committee for Aeronautics score <3. The primary outcome was the proportion of patients treated with TXA according to guidelines. The European guidelines were represented by the risk of death from bleeding (calculated retrospectively using the Bleeding Audit for Trauma and Triage (BATT) score). Factors impacting the likelihood of receiving TXA were assessed by multivariate analysis.

RESULTS

Of 13 944 patients included in the study, 2401 (17.2%) were considered at risk of death from bleeding. Among these, 257 (11%) received prehospital TXA. This represented 38% of those meeting US guidelines. For European guidelines, the treatment rate increased with the risk of death from bleeding: 6% (95% CI 4.4% to 7.0%) for low risk (BATT score 3-4); 13% (95% CI 11.1% to 15.9%) for intermediate risk (BATT score 5-7); and 21% (95% CI 17.6% to 25.6%) for high risk (BATT score ≥8) (p<0.01). Women and the elderly were treated less often than men and younger patients, irrespective of the risk of death from bleeding and the mechanism of injury.

CONCLUSION

The proportion of injured patients receiving TXA in the prehospital setting of the State of Vaud in Switzerland was low, with even lower rates for women and older patients. The reasons for this undertreatment are probably multifactorial and would require specific studies to clarify and correct them.

Intravenous tranexamic acid significantly improved visualization and shortened the operation time in microscopic middle ear surgery: a randomized controlled trial

BACKGROUND

The microscopic middle ear surgery involves a limited operating space and numerous important anatomical structures in which good visualization is crucial, as even a small amount of bleeding can greatly affect the clarity of surgical field. This study aims to investigate whether intravenous 1 g of tranexamic acid can improve surgical visualization and further shorten the operation time in microscopic middle ear surgery.

METHODS

This study is a prospective, randomized, double-blind, controlled trial conducted from December 2021 to December 2022, enrolling patients who were scheduled for microscopic modified radical mastoidectomy due to chronic otitis media. In addition to standard techniques to optimize the surgical field, participants were randomized into the TXA (tranexamic acid) group (1 g diluted to 20 ml normal saline) and the control group (20 ml normal saline). The primary outcome was assessed based on the clarity of the surgical field using the Modena Bleeding Score. Secondary outcomes included operation time, the surgeon satisfaction with the visual clarity, postoperative 24 h coagulation parameters, and the incidence of adverse events. Student's t -test, χ2 test, and ANOVA of repeated measures were used for statistical analyses.

RESULTS

A total of 28 patients were enrolled in each group using a 1:1 randomized allocation with similar demographic characteristics, including 24 male and 32 female individuals, and the mean age is 45.6±11.9 years. The surgical visualization in the TXA group was significantly better than that of the control group (2.29±0.46 vs. 2.89±0.31, P <0.001) as assessed by the Modena Bleeding Score. Furthermore, the TXA group demonstrated a shorter operation time compared to the control group (88.61±10.9 vs. 105.2±15.9, P <0.001) and higher surgeon satisfaction with surgical field (7.82±0.55 vs. 6.50±0.64, P <0.001). No statistically significant differences were found in postoperative coagulation parameters in the two groups. No TXA-related adverse events or complications occurred during the 12-month follow-up.

CONCLUSION

Intravenous 1 g of TXA can further significantly improve the visual clarity in the microscopic middle ear surgery and shorten the operation time based on other standard measures implemented.

Tranexamic Acid: An Evergreen Hemostatic Agent

Tranexamic acid (TXA) is an important antifibrinolytic agent, which inhibits plasminogen activation and fibrinolysis. Several controlled randomized trials have investigated the role of TXA in preventing or decreasing blood loss across different surgical interventions or medical conditions characterized by excessive bleeding, consistently documenting its effectiveness and safety. Although the first clinical use of TXA dates back to more than 60 years ago, TXA remains the focus of intense research. This narrative review summarizes the more recent results and indications on the clinical use of TXA.

Tranexamic acid in patients with traumatic brain injury: a meta-analysis

BACKGROUND

We performed a meta-analysis to assess the effectiveness and safety of tranexamic acid in patients with traumatic brain injury (TBI).

METHODS

We searched the literature for articles evaluating the effectiveness and safety of tranexamic acid (TXA) in TBI published between January 2012 and January 2021, and identified 8 studies with a total of 10860 patients: 5660 received TXA and 5200 served as controls. We used a dichotomous or continuous approach with a random or fixed-effect model to assess the efficacy and safety of TXA in TBI, and calculated the mean difference (MD) and odds ratio (OR) with the corresponding 95% confidence interval.

RESULTS

In patients with TBI, early administration of TXA was associated with a greater relative benefit (MD -2.45; 95% CI = -4.78 to -0.12; p=0.04) and less total haematoma expansion (MD - 2.52; 95% CI = -4.85 to -0.19; p=0.03) compared to controls. There were no statistically significant differences in mortality (OR 0.94; 95% CI=0.85-1.03; p=0.18), presence of progressive haemorrhage (OR 0.75; 95% CI=0.56-1.01; p=0.06), need for neurosurgery (OR 1.15; 95% CI=0.66-1.98; p=0.63), high Disability Rating Scale score (OR 0.90; 95% CI=0.56-1.45; p=0.68), and incidence of ischaemic or thromboembolic complications (OR 1.34; 95% CI=0.33-5.46; p=0.68) between TBI patients treated with TXA and controls.

CONCLUSIONS

Early administration of TXA in TBI patients may have a greater relative benefit and may inhibit haematoma expansion. There were no significant differences in mortality, presence of progressive haemorrhage, need for neurosurgery, high Disability Rating Scale score, and incidence of ischaemic or thromboembolic complications between TBI patients treated with TXA and controls. Further studies are needed to validate these results.

Lack of efficacy of aprotinin over tranexamic acid in type A aortic dissection repair

BACKGROUND

The role of aprotinin in modern cardiac surgery is not well defined. While licensed for use in isolated coronary artery bypass grafting it is more commonly used for cases deemed to be at an increased risk of bleeding. The relative efficacy, and safety profile, of aprotinin as compared to other antifibrinolytics in these high-risk cases is uncertain.

STUDY DESIGN AND METHODS

A retrospective observational study with propensity matching to determine whether aprotinin versus tranexamic acid reduced bleeding or transfusion requirements in patients presenting for surgical repair of type A aortic dissection (TAD).

RESULTS

Between 2016 and 2022, 250 patients presented for repair of TAD. A total of 231 patients were included in the final analysis. Bleeding and transfusion were similar between both groups in both propensity matched and unmatched cohorts. Compared to tranexamic acid, aprotinin use did not reduce transfusion requirements for any product. Rates of bleeding in the first 12 h, return to theater and return to intensive care unit with an open packed chest were similar between groups. There was no difference in rates of renal failure, stroke, or death.

CONCLUSION

Aprotinin did not reduce the risk of bleeding or transfusion requirements in patients undergoing repair of type A aortic dissections. Efficacy of aprotinin may vary depending on the type of surgery performed and the underlying pathology.

Evaluating tranexamic acid for the prevention and treatment of obstetric hemorrhage

PURPOSE OF REVIEW

Tranexamic acid (TXA) has emerged as a promising pharmacological adjunct to treat and prevent postpartum hemorrhage (PPH). We provide an overview of TXA, including its pharmacology, key findings of randomized trials and observational studies, and critical patient safety information.

RECENT FINDINGS

Pharmacokinetic data indicate that TXA infusions result in peak plasma concentration within 3 min (range: 1-6.6 min). Ex-vivo pharmacodynamic data suggest that low-dose TXA (5 mg/kg) inhibits maximum lysis for at least 1 h. In predominantly developing countries, TXA has demonstrated a 19% reduction in the risk of bleeding-related death among patients with PPH. Based on high-quality randomized trials, TXA prophylaxis does not effectively reduce the risk of PPH during vaginal delivery and is likely ineffective in reducing the PPH risk during cesarean delivery. TXA exposure does not increase the risk of maternal thrombotic events. Maternal deaths have occurred from accidental intrathecal TXA injection from look-alike medication errors.

SUMMARY

TXA has shown promise as an important adjunct for PPH treatment, especially in low-resource settings. However, TXA is not recommended as PPH prophylaxis during vaginal or cesarean delivery. Patient safety initiatives should be prioritized to prevent maternal death from accidental intrathecal TXA injection.

Early Goal-Directed Hemostatic Therapy for Severe Acute Bleeding Management in the Intensive Care Unit: A Narrative Review

This is a narrative review of the published evidence for bleeding management in critically ill patients in different clinical settings in the intensive care unit (ICU). We aimed to describe "The Ten Steps" approach to early goal-directed hemostatic therapy (EGDHT) using point-of-care testing (POCT), coagulation factor concentrates, and hemostatic drugs, according to the individual needs of each patient. We searched National Library of Medicine, MEDLINE for publications relevant to management of critical ill bleeding patients in different settings in the ICU. Bibliographies of included articles were also searched to identify additional relevant studies. English-language systematic reviews, meta-analyses, randomized trials, observational studies, and case reports were reviewed. Data related to study methodology, patient population, bleeding management strategy, and clinical outcomes were qualitatively evaluated. According to systematic reviews and meta-analyses, EGDHT guided by viscoelastic testing (VET) has been associated with a reduction in transfusion utilization, improved morbidity and outcome in patients with active bleeding. Furthermore, literature data showed an increased risk of severe adverse events and poor clinical outcomes with inappropriate prophylactic uses of blood components to correct altered conventional coagulation tests (CCTs). Finally, prospective, randomized, controlled trials point to the role of goal-directed fibrinogen substitution to reduce bleeding and the amount of red blood cell (RBC) transfusion with the potential to decrease mortality. In conclusion, severe acute bleeding management in the ICU is still a major challenge for intensive care physicians. The organized and sequential approach to the bleeding patient, guided by POCT allows for rapid and effective bleeding control, through the rational use of blood components and hemostatic drugs, since VET can identify specific coagulation disorders in real time, guiding hemostatic therapy with coagulation factor concentrates and hemostatic drugs with individual goals.

Lipid nanoparticles and siRNA targeting plasminogen provide lasting inhibition of fibrinolysis in mouse and dog models of hemophilia A

Antifibrinolytic drugs are used extensively for on-demand treatment of severe acute bleeding. Controlling fibrinolysis may also be an effective strategy to prevent or lessen chronic recurring bleeding in bleeding disorders such as hemophilia A (HA), but current antifibrinolytics have unfavorable pharmacokinetic profiles. Here, we developed a long-lasting antifibrinolytic using small interfering RNA (siRNA) targeting plasminogen packaged in clinically used lipid nanoparticles (LNPs) and tested it to determine whether reducing plasmin activity in animal models of HA could decrease bleeding frequency and severity. Treatment with the siRNA-carrying LNPs reduced circulating plasminogen and suppressed fibrinolysis in wild-type and HA mice and dogs. In HA mice, hemostatic efficacy depended on the injury model; plasminogen knockdown improved hemostasis after a saphenous vein injury but not tail vein transection injury, suggesting that saphenous vein injury is a murine bleeding model sensitive to the contribution of fibrinolysis. In dogs with HA, LNPs carrying siRNA targeting plasminogen were as effective at stabilizing clots as tranexamic acid, a clinical antifibrinolytic, and in a pilot study of two dogs with HA, the incidence of spontaneous or excess bleeding was reduced during 4 months of prolonged knockdown. Collectively, these data demonstrate that long-acting antifibrinolytic therapy can be achieved and that it provides hemostatic benefit in animal models of HA.

Does tranexamic acid have a positive effect on the outcome of older multiple trauma patients on antithrombotic drugs? An analysis using the TraumaRegister DGU®

Background

Acute hemorrhage is one of the most common causes of death in multiple trauma patients. Due to physiological changes, pre-existing conditions, and medication, older trauma patients are more prone to poor prognosis. Tranexamic acid (TXA) has been shown to be beneficial in multiple trauma patients with acute hemorrhage in general. The relation of tranexamic acid administration on survival in elderly trauma patients with pre-existing anticoagulation is the objective of this study. Therefore, we used the database of the TraumaRegister DGU® (TR-DGU), which documents data on severely injured trauma patients.

Methods

In this retrospective analysis, we evaluated the TR-DGU data from 16,713 primary admitted patients with multiple trauma and age &gt; =50 years from 2015 to 2019. Patients with pre-existing anticoagulation and TXA administration (996 patients, 6%), pre-existing anticoagulation without TXA administration (4,807 patients, 28.8%), without anticoagulation as premedication but TXA administration (1,957 patients, 11.7%), and without anticoagulation and TXA administration (8,953 patients, 53.6%) were identified. A regression analysis was performed to investigate the influence of pre-existing antithrombotic drugs and TXA on mortality. A propensity score was created in patients with pre-existing anticoagulation, and matching was performed for better comparability of patients with and without TXA administration.

Results

Retrospective trauma patients who underwent tranexamic acid administration were older and had a higher ISS than patients without tranexamic acid donation. Predicted mortality (according to the RISC II Score) and observed mortality were higher in the group with tranexamic acid administration. The regression analysis showed that TXA administration was associated with lower mortality rates within the first 24 h in older patients with anticoagulation as premedication. The propensity score analysis referred to higher fluid requirement, higher requirement of blood transfusion, and longer hospital stay in the group with tranexamic acid administration. There was no increase in complications. Despite higher transfusion volumes, the tranexamic acid group had a comparable all-cause mortality rate.

Conclusion

TXA administration in older trauma patients is associated with a reduced 24-h mortality rate after trauma, without increased risk of thromboembolic events. There is no relationship between tranexamic acid and overall mortality in patients with anticoagulation as premedication. Considering pre-existing anticoagulation, tranexamic acid may be recommended in elderly trauma patients with acute bleeding.

Pre-hospital tranexamic acid administration in patients with a severe hemorrhage: an evaluation after the implementation of tranexamic acid administration in the Dutch pre-hospital protocol

PURPOSE

To evaluate the pre-hospital administration of tranexamic acid in ambulance-treated trauma patients with a severe hemorrhage after the implementation of tranexamic acid administration in the Dutch pre-hospital protocol.

METHODS

All patients with a severe hemorrhage who were treated and conveyed by EMS professionals between January 2015, and December 2017, to any trauma-receiving emergency department in the eight participating trauma regions in the Netherlands, were included. A severe hemorrhage was defined as extracranial injury with > 20% body volume blood loss, an extremity amputation above the wrist or ankle, or a grade ≥ 4 visceral organ injury. The main outcome was to determine the proportion of patients with a severe hemorrhage who received pre-hospital treatment with tranexamic acid. A Generalized Linear Model (GLM) was performed to investigate the relationship between pre-hospital tranexamic acid treatment and 24 h mortality.

RESULTS

A total of 477 patients had a severe hemorrhage, of whom 124 patients (26.0%) received tranexamic acid before arriving at the hospital. More than half (58.4%) of the untreated patients were suspected of a severe hemorrhage by EMS professionals. Patients treated with tranexamic acid had a significantly lower risk on 24 h mortality than untreated patients (OR 0.43 [95% CI 0.19-0.97]).

CONCLUSION

Approximately a quarter of the patients with a severe hemorrhage received tranexamic acid before arriving at the hospital, while a severe hemorrhage was suspected in more than half of the non-treated patients. Severely hemorrhaging patients treated with tranexamic acid before arrival at the hospital had a lower risk to die within 24 h after injury.

How I treat von Willebrand disorders in older adults

ABSTRACT

von Willebrand disease (VWD) is the most common bleeding disorder and especially milder type 1 VWD might not be cared for in specialty clinics. VW factor levels rise with age, but the rise of these levels does not necessarily correlate with bleeding risk. A recent bleeding history combined with recent labs are important for hemostatic management decision during surgical interventions. Antifibrinolytics appear safe in the population of older adults, whereas desmopressin (DDAVP) should be used cautiously. Where needed, factor concentrates present a great treatment option. Acquired von Willebrand syndrome is vastly underrecognized, but likely to surface in the aging, especially in the setting of comorbidities, such as plasma-cell dyscrasias. Intravenous immunoglobulin can be an effective treatment in this scenario, but potentially increases thrombotic risk.

Quick model-based viscoelastic clot strength predictions from blood protein concentrations for cybermedical coagulation control

Cybermedical systems that regulate patient clotting in real time with personalized blood product delivery will improve treatment outcomes. These systems will harness popular viscoelastic assays of clot strength such as thromboelastography (TEG), which help evaluate coagulation status in numerous conditions: major surgery (e.g., heart, vascular, hip fracture, and trauma); liver cirrhosis and transplants; COVID-19; ICU stays; sepsis; obstetrics; diabetes; and coagulopathies like hemophilia. But these measurements are time-consuming, and thus impractical for urgent care and automated coagulation control. Because protein concentrations in a blood sample can be measured in about five minutes, we develop personalized, phenomenological, quick, control-oriented models that predict TEG curve outputs from input blood protein concentrations, to facilitate treatment decisions based on TEG curves. Here, we accurately predict, experimentally validate, and mechanistically justify curves and parameters for common TEG assays (Functional Fibrinogen, Citrated Native, Platelet Mapping, and Rapid TEG), and verify results with trauma patient clotting data.

Comparative analysis of hyperfibrinolysis with activated coagulation between amniotic fluid embolism and severe placental abruption

Amniotic fluid embolism (AFE) and placental abruption (PA) are typical obstetric diseases associated with disseminated intravascular coagulation (DIC). AFE is more likely to be complicated with enhanced fibrinolysis than PA. AFE may have an additional mechanism activating fibrinolytic cascade. We aimed to compare the coagulation/fibrinolysis factors among AFE, PA, and peripartum controls. We assessed AFE cases registered in the Japanese AFE Registry, and PA cases complicated with DIC (severe PA) and peripartum controls recruited at our hospital. The following factors in plasma were compared: prothrombin fragment 1 + 2 (PF1 + 2), plasmin α2-plasmin inhibitor complex (PIC), tissue factor (TF), tissue plasminogen activator (tPA), annexin A2 (AnnA2), total thrombin activatable fibrinolysis inhibitor (TAFI) including its activated form (TAFIa), and plasminogen activator inhibitor-type 1 (PAI-1). PF1 + 2 and PIC were markedly increased in both AFE (n = 27) and severe PA (n = 12) compared to controls (n = 23), without significant difference between those disease groups; however, PIC in AFE showed a tendency to elevate relative to PF1 + 2, compared with severe PA. AFE had significantly increased tPA and decreased total TAFI levels compared with severe PA and controls, which might be associated with further plasmin production in AFE and underlie its specific fibrinolytic activation pathway.

Tranexamic acid for the prevention and treatment of postpartum hemorrhage in resource-limited settings: a literature review

Introduction

Postpartum haemorrhage is a major cause of maternal morbidity and mortality worldwide. Early recognition and appropriate treatment are crucial for managing postpartum haemorrhage.

Objectives

This literature review aimed to evaluate the efficacy of tranexamic acid in the prevention and treatment of postpartum haemorrhage in resource-limited settings.

Search methods

This literature review was conducted based on the Preferred Reporting Items for Systematic Review and Meta-analyses (PRISMA) guidelines. A computerized systematic search of the MEDLINE (PubMed), Google Scholar, and Cochrane databases using a combination of the following Medical Subject Headings (MeSH) terms for PubMed: [(obstetric haemorrhage OR postpartum haemorrhage OR massive obstetric haemorrhage) AND (tranexamic acid OR antifibrinolytic drugs) AND (prophylaxis OR prevention) AND (management OR treatment) AND (resource-limited settings OR resource-limited area OR developing countries)] to find articles published in English since 2010.

Selection criteria

Studies on the obstetric population who underwent vaginal or caesarean delivery, comparing the use of tranexamic acid versus placebo (or no treatment) for treatment (or prevention) of postpartum haemorrhage with the outcome of postpartum haemorrhage rate, blood transfusion requirements, uterotonics requirements, hysterectomy, or mortality were included.

Result

In total, 5315 articles were identified. Following the elimination of duplicates, the methodological quality of 15 studies was evaluated independently, with eligibility determined based on the inclusion and exclusion criteria, as well as outcome variables. Finally, eight articles were included in the review.

Conclusion

This review provides evidence that the administration of tranexamic acid has the potential to decrease the need for blood transfusion, incidence of postpartum haemorrhage, demand for supplementary uterotonics, and maternal morbidity and mortality with marginal adverse effects. Healthcare systems must develop and implement interventions that involve the use of tranexamic acid for the treatment of postpartum haemorrhage in resource-limited settings.

Tranexamic acid by the intramuscular or intravenous route for the prevention of postpartum haemorrhage in women at increased risk: a randomised placebo-controlled trial (I'M WOMAN)

BACKGROUND

Postpartum haemorrhage (PPH) causes about 70,000 maternal deaths every year. Tranexamic acid (TXA) is a life-saving treatment for women with PPH. Intravenous (IV) TXA reduces deaths due to PPH by one-third when given within 3 h of childbirth. Because TXA is more effective when given early and PPH usually occurs soon after childbirth, giving TXA just before childbirth might prevent PPH. Although several randomised trials have examined TXA for PPH prevention, the results are inconclusive. Because PPH only affects a small proportion of births, we need good evidence on the balance of benefits and harms before using TXA to prevent PPH. TXA is usually given by slow IV injection. However, recent research shows that TXA is well tolerated and rapidly absorbed after intramuscular (IM) injection, achieving therapeutic blood levels within minutes of injection.

METHODS

The I'M WOMAN trial is an international, multicentre, three-arm, randomised, double-blind, placebo-controlled trial to assess the effects of IM and IV TXA for the prevention of PPH in women with one or more risk factors for PPH giving birth vaginally or by caesarean section.

DISCUSSION

The trial will provide evidence of the benefits and harms of TXA for PPH prevention and the effects of the IM and IV routes of administration. The IM route should be as effective as the IV route for preventing bleeding. There may be fewer side effects with IM TXA because peak blood concentrations are lower than with the IV route. IM TXA also has practical advantages as it is quicker and simpler to administer. By avoiding the need for IV line insertion and a slow IV injection, IM administration would free up overstretched midwives and doctors to focus on looking after the mother and baby and expand access to timely TXA treatment.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05562609. Registered on 3 October 2022. ISRCTN Registry ISRCTN12590098. Registered on 20 January 2023. Pan African Clinical Trial Registry PACTR202305473136570. Registered on 18 May 2023.

Nationwide analysis of prehospital tranexamic acid for trauma demonstrates systematic bias in adherence to treatment guidelines: a retrospective cohort study

BACKGROUND

Prehospital (PH) tranexamic acid (TXA) improves survival from trauma haemorrhage. Injury mechanism, physiology, and sex demographics vary with patient age. The authors hypothesised that these factors influence TXA guideline compliance and examined national trends in PH use to identify any systematic biases in bleeding management.

MATERIALS AND METHODS

The UK Trauma Audit and Research Network data for TXA eligible patients admitted to major trauma centres were divided into two cohorts: 2013-2015 ( n =32 072) and 2017-2019 ( n =14 974). Patients were stratified by PH, emergency department or no TXA use. Logistic regression models explored interaction between PH variables and TXA administration. Results are presented as odds ratios with a 95% CI.

RESULTS

PH TXA use increased from 8% to 27% over time ( P <0.001). Only 3% of eligible patients who fell less than 2 m received PH TXA versus 63% with penetrating injuries ( P <0.001). Older patients eligible for PH TXA were less likely to receive it compared to younger patients [≥65 years old: 590 (13%) vs. <65 years old: 3361 (33%), P <0.001]. There was a significant interaction between age and sex with fewer older women receiving PH TXA. In shocked patients, one third of females compared to a fifth of men did not receive TXA ( P <0.001). There was a decrease in PH TXA use as age increased ( P <0.001).

CONCLUSIONS

Despite a threefold increase in use, treatment guidance for PH TXA is not universally applied. Older people, women, and patients with low energy injury mechanisms appear to be systematically under treated. Training and education for PH providers should address these potential treatment biases.

The Effectiveness of Prehospital Administration of Tranexamic Acid in Reducing Mortality in Trauma Patients: An Overview

Tranexamic acid (TXA) is an antifibrinolytic drug that reduces bleeding by inhibiting plasminogen activation and fibrin clot degradation. Its role in prehospital trauma management remains unclear. This article aims to systematically review the current evidence on the effect of prehospital TXA administration on mortality in adult and pediatric trauma patients. A literature search was conducted of PubMed, Web of Science, Scopus, and Cochrane databases from March 2023 to August 2023 for studies evaluating the impact of prehospital TXA use on trauma mortality. Inclusion criteria were articles published in the English language in the past 20 years focusing on clinical outcomes of prehospital TXA administration. Data on all-cause mortality, thromboembolic events, and time to TXA administration were extracted. In adult trauma, prehospital TXA appears to reduce early all-cause mortality when given within three hours of injury without increasing thromboembolic risks. Some studies found decreased delayed mortality, while others found no difference. In pediatric trauma, preliminary evidence suggests TXA may lower in-hospital mortality in hemodynamically unstable patients, though higher doses may increase seizure risk. Early prehospital administration of TXA within three hours of adult trauma may reduce mortality through improved hemorrhage control. Potential benefits in pediatric trauma warrant further investigation, balancing efficacy against safety risks such as seizures from high doses. Well-designed randomized trials are needed to validate optimal TXA dosing strategies across age groups and injury severity levels.

Cost of the Defence Medical Services Patient Group Directive for a 10-minute tranexamic acid (TXA) infusion in trauma: a bolus is safe and saves lives

Tranexamic acid (TXA) is a life-saving drug that reduces the risk of death from haemorrhage. Intervention is time critical with benefit decreasing with delayed administration. The current Joint Service Publication Patient Group Directive (PGD) for giving TXA during the tactical field care phase of the operational patient care pathway specifies it is given over 10 min via intravenous infusion based on TXA's Summary of Product Characteristics. This paper aims to explore the risks of administering TXA as a bolus rather than a 10-minute infusion. There is little evidence to support the risk of quoted adverse events from bolus administration of TXA, good-quality evidence for the mortality benefit of early administration and some evidence that bolus dosing is safe. The Defence Medical Service should consider a default PGD of rapid TXA administration to maximise mortality benefit.

HOW SHOULD TRANEXAMIC ACID BE ADMINISTERED IN HEMORRHAGIC SHOCK? CONTINUOUS SERUM CONCENTRATION MEASUREMENTS IN A SWINE MODEL

ABSTRACT

Background : Tranexamic acid (TXA) reduces mortality in trauma patients. Intramuscular (IM) administration could be advantageous in low-resource and military settings. Achieving the same serum concentration as intravenous (IV) administration is important to achieve equal mortality reduction. Therefore, we aimed to investigate whether dividing an IM dose of TXA between two injection sites and whether an increase in dose would lead to serum concentrations comparable to those achieved by IV administration. Methods : Norwegian landrace pigs (n = 29) from a course in hemostatic emergency surgery were given TXA 1 h after start of surgery. Blood samples were drawn at 0, 5, 10, 15, 20, 25, 35, 45, 60, and 85 min. The samples were centrifuged and serum TXA concentrations quantified with liquid chromatography-tandem mass spectrometry. The use of two injection sites was compared with distributing the dose on one injection site, and a dose of 15 mg/kg was compared with a dose of 30 mg/kg. All IM groups were compared with IV administration. Results : The groups were in a similar degree of shock. Increasing the IM dose from the standard of 15 mg/kg to 30 mg/kg resulted in significantly higher serum concentrations of TXA, comparable to those achieved by IV administration. Distributing the IM dose on two injection sites did not affect drug uptake, as shown by equal serum concentrations. Conclusions : For IM administration of TXA, 30 mg/kg should be the standard dose. With a short delay, IM administration will provide equal serum concentrations as IV administration, above what is considered necessary to inhibit fibrinolysis.

Prehospital tranexamic acid is associated with a dose-dependent decrease in syndecan-1 after trauma: A secondary analysis of a prospective randomized trial

BACKGROUND

In the Study of Tranexamic Acid During Air and Ground Prehospital Transport (STAAMP) Trial, prehospital tranexamic acid (TXA) was associated with lower mortality in specific patient subgroups. The underlying mechanisms responsible for a TXA benefit remain incompletely characterized. We hypothesized that TXA may mitigate endothelial injury and sought to assess whether TXA was associated with decreased endothelial or tissue damage markers among all patients enrolled in the STAAMP Trial.

METHODS

We collected blood samples from STAAMP Trial patients and measured markers of endothelial function and tissue damage including syndecan-1, soluble thrombomodulin (sTM), and platelet endothelial cell adhesion molecule-1 at hospital admission (0 hours) and 12 hours, 24 hours, and 72 hours after admission. We compared these marker values for patients in each treatment group during the first 72 hours, and modeled the relationship between TXA and marker concentration using regression analysis to control for potential confounding factors.

RESULTS

We analyzed samples from 766 patients: 383 placebo, 130 abbreviated dosing, 119 standard dosing, and 130 repeat dosing. Lower levels of syndecan-1, TM, and platelet endothelial cell adhesion molecule measured within the first 72 hours of hospital admission were associated with survival at 30 days ( p < 0.001). At hospital admission, syndecan-1 was lower in the TXA group (28.30 [20.05, 42.75] vs. 33.50 [23.00, 54.00] p = 0.001) even after controlling for patient, injury, and prehospital factors ( p = 0.001). For every 1 g increase in TXA administered over the first 8 hours of prehospital transport and hospital admission, there was a 4-ng/mL decrease in syndecan-1 at 12 hours controlling for patient, injury, and treatment factors ( p = 0.03).

CONCLUSION

Prehospital TXA was associated with decreased syndecan-1 at hospital admission. Syndecan-1 measured 12 hours after admission was inversely related to the dose of TXA received. Early prehospital and in-hospital TXA may decrease endothelial glycocalyx damage or upregulate vascular repair mechanisms in a dose-dependent fashion.

LEVEL OF EVIDENCE

Therapeutic/Care Management; Level III.

Prehospital tranexamic acid in trauma patients: a systematic review and meta-analysis of randomized controlled trials

Background

Prehospital tranexamic acid (TXA) may hold substantial benefits for trauma patients; however, the data underlying its efficacy and safety is scarce.

Methods

We searched PubMed, Embase, the Cochrane Library, and ClinicalTrials.gov from inception to July 2023 for all randomized controlled trials (RCTs) investigating prehospital TXA in trauma patients as compared to placebo or standard care without TXA. Data were pooled under a random-effects model using RevMan 5.4 with risk ratio (RR) and mean difference (MD) as the effect measures.

Results

A total of three RCTs were included in this review. Regarding the primary outcomes, prehospital TXA reduced the risk of 1-month mortality (RR 0.82, 95% CI 0.69-0.97) but did not increase survival with a favorable functional outcome at 6 months (RR 1.00, 95% CI 0.93-1.09). Prehospital TXA also reduced the risk of 24-h mortality but did not affect the risk of mortality due to bleeding and traumatic brain injury. There was no significant difference between the TXA and control groups in the incidence of RBC transfusion, and the number of ventilator- and ICU-free days. Prehospital TXA did not increase the risk of adverse events except for a small increase in the incidence of infections.

Conclusion

Prehospital TXA is useful in reducing mortality in trauma patients without a notable increase in the risk of adverse events. However, there was no effect on the 6-month favorable functional status. Further large-scale trials are required to validate the aforementioned findings.

Systematic review registration

PROSPERO (CRD42023451759).

Tranexamic Acid (TXA) for the Hemostatic Treatment of Post-Partum Hemorrhage (PPH): What Key Points Have We Learnt After All These Years?

Post-partum bleeding or post-partum hemorrhage (PPH) is often defined as the loss of more than 500 mL of blood after vaginal delivery or 1000 mL of blood after cesarean section following the delivery of a child [...].

A new global fibrinolysis capacity assay for the sensitive detection of hyperfibrinolysis and hypofibrinogenemia in trauma patients

BACKGROUND

Conventional clotting tests are not expeditious enough to allow timely targeted interventions in trauma, and current point-of-care analyzers, such as rotational thromboelastometry (ROTEM), have limited sensitivity for hyperfibrinolysis and hypofibrinogenemia.

OBJECTIVES

To evaluate the performance of a recently developed global fibrinolysis capacity (GFC) assay in identifying fibrinolysis and hypofibrinogenemia in trauma patients.

METHODS

Exploratory analysis of a prospective cohort of adult trauma patients admitted to a single UK major trauma center and of commercially available healthy donor samples was performed. Lysis time (LT) was measured in plasma according to the GFC manufacturer's protocol, and a novel fibrinogen-related parameter (percentage reduction in GFC optical density from baseline at 1 minute) was derived from the GFC curve. Hyperfibrinolysis was defined as a tissue factor-activated ROTEM maximum lysis of >15% or LT of ≤30 minutes.

RESULTS

Compared to healthy donors (n = 19), non-tranexamic acid-treated trauma patients (n = 82) showed shortened LT, indicative of hyperfibrinolysis (29 minutes [16-35] vs 43 minutes [40-47]; p < .001). Of the 63 patients without overt ROTEM-hyperfibrinolysis, 31 (49%) had LT of ≤30 minutes, with 26% (8 of 31) of them requiring major transfusions. LT showed increased accuracy compared to maximum lysis in predicting 28-day mortality (area under the receiver operating characteristic curve, 0.96 [0.92-1.00] vs 0.65 [0.49-0.81]; p = .001). Percentage reduction in GFC optical density from baseline at 1 minute showed comparable specificity (76% vs 79%) to ROTEM clot amplitude at 5 minutes from tissue factor-activated ROTEM with cytochalasin D in detecting hypofibrinogenemia but correctly reclassified >50% of the patients with false negative results, leading to higher sensitivity (90% vs 77%).

CONCLUSION

Severe trauma patients are characterized by a hyperfibrinolytic profile upon admission to the emergency department. The GFC assay is more sensitive than ROTEM in capturing hyperfibrinolysis and hypofibrinogenemia but requires further development and automation.

Validating indicators for monitoring availability and geographic distribution of emergency obstetric and newborn care (EmoNC) facilities: A study triangulating health system, facility, and geospatial data

Availability of emergency obstetric and newborn care (EmONC) is a strong supply side measure of essential health system capacity that is closely and causally linked to maternal mortality reduction and fundamentally to achieving universal health coverage. The World Health Organization's indicator "Availability of EmONC facilities" was prioritized as a core indicator to prevent maternal death. The indicator focuses on whether there are sufficient emergency care facilities to meet the population need, but not all facilities designated as providing EmONC function as such. This study seeks to validate "Availability of EmONC" by comparing the value of the indicator after accounting for key aspects of facility functionality and an alternative measure of geographic distribution. This study takes place in four subnational geographic areas in Argentina, Ghana, and India using a census of all birthing facilities. Performance of EmONC in the 90 days prior to data collection was assessed by examining facility records. Data were collected on facility operating hours, staffing, and availability of essential medications. Population estimates were generated using ArcGIS software using WorldPop to estimate the total population, and the number of women of reproductive age (WRA), pregnancies and births in the study areas. In addition, we estimated the population within two-hours travel time of an EmONC facility by incorporating data on terrain from Open Street Map. Using these data sources, we calculated and compared the value of the indicator after incorporating data on facility performance and functionality while varying the reference population used. Further, we compared its value to the proportion of the population within two-hours travel time of an EmONC facility. Included in our study were 34 birthing facilities in Argentina, 51 in Ghana, and 282 in India. Facility performance of basic EmONC (BEmONC) and comprehensive EmONC (CEmONC) signal functions varied considerably. One facility (4.8%) in Ghana and no facility in India designated as BEmONC had performed all seven BEmONC signal functions. In Argentina, three (8.8%) CEmONC-designated facilities performed all nine CEmONC signal functions, all located in Buenos Aires Region V. Four CEmONC-designated facilities in Ghana (57.1%) and the three CEmONC-designated facilities in India (23.1%) evidenced full CEmONC performance. No sub-national study area in Argentina or India reached the target of 5 BEmONC-level facilities per 20,000 births after incorporating facility functionality yet 100% did in Argentina and 50% did in India when considering only facility designation. Demographic differences also accounted for important variation in the indicator's value. In Ghana, the total population in Tolon within 2 hours travel time of a designated EmONC facility was estimated at 99.6%; however, only 91.1% of women of reproductive age were within 2 hours travel time. Comparing the value of the indicator when calculated using different definitions reveals important inconsistencies, resulting in conflicting information about whether the threshold for sufficient coverage is met. This raises important questions related to the indicator's validity. To provide a valid measure of effective coverage of EmONC, the construct for measurement should extend beyond the most narrow definition of availability and account for functionality and geographic accessibility.

Tranexamic Acid for Intracerebral Hemorrhage in Patients on Non-Vitamin K Antagonist Oral Anticoagulants (TICH-NOAC): A Multicenter, Randomized, Placebo-Controlled, Phase 2 Trial

BACKGROUND

Evidence-based hemostatic treatment for intracerebral hemorrhage (ICH) associated with non-vitamin K antagonist oral anticoagulants (NOACs) is lacking. Tranexamic acid (TXA) is an antifibrinolytic drug potentially limiting hematoma expansion. We aimed to assess the efficacy and safety of TXA in NOAC-ICH.

METHODS

We performed a double-blind, randomized, placebo-controlled trial at 6 Swiss stroke centers. Patients with NOAC-ICH within 12 hours of symptom onset and 48 hours of last NOAC intake were randomized (1:1) to receive either intravenous TXA (1 g over 10 minutes followed by 1 g over 8 hours) or matching placebo in addition to standard medical care via a centralized Web-based procedure with minimization on key prognostic factors. All participants and investigators were masked to treatment allocation. Primary outcome was hematoma expansion, defined as ≥33% relative or ≥6 mL absolute volume increase at 24 hours and analyzed using logistic regression adjusted for baseline hematoma volume on an intention-to-treat basis.

RESULTS

Between December 12, 2016, and September 30, 2021, we randomized 63 patients (median age, 82 years [interquartile range, 76-86]; 40% women; median hematoma volume, 11.5 [4.8-27.4] mL) of the 109 intended sample size before premature trial discontinuation due to exhausted funding. The primary outcome did not differ between TXA (n=32) and placebo (n=31) arms (12 [38%] versus 14 [45%]; adjusted odds ratio, 0.63 [95% CI, 0.22-1.82]; P=0.40). There was a signal for interaction with onset-to-treatment time (Pinteraction=0.024), favoring TXA when administered within 6 hours of symptom onset. Between the TXA and placebo arms, the proportion of participants who died (15 [47%] versus 13 [42%]; adjusted odds ratio, 1.07 [0.37-3.04]; P=0.91) or had major thromboembolic complications within 90 days (4 [13%] versus 2 [6%]; odds ratio, 1.86 [0.37-9.50]; P=0.45) did not differ. All thromboembolic events occurred at least 2 weeks after study treatment, exclusively in participants not restarted on oral anticoagulation.

CONCLUSIONS

In a smaller-than-intended NOAC-ICH patient sample, we found no evidence that TXA prevents hematoma expansion, but there were no major safety concerns. Larger trials on hemostatic treatments targeting an early treatment window are needed for NOAC-ICH.

REGISTRATION

URL: https://clinicaltrials.gov; Unique identifier: NCT02866838.

Tranexamic acid for the prevention of postpartum bleeding in women with anaemia: Statistical analysis plan for the WOMAN-2 trial: an international, randomised, placebo-controlled trial

Background: Postpartum haemorrhage (PPH) is responsible for over 50,000 maternal deaths every year. Most of these deaths are in low- and middle-income countries. Tranexamic acid (TXA) reduces bleeding by inhibiting the enzymatic breakdown of fibrin blood clots. TXA decreases surgical bleeding and reduces deaths from bleeding after traumatic injury. When given within three hours of birth, TXA reduces deaths from bleeding in women with PPH. However, for many women, treatment of PPH is too late to prevent death. World-wide, over one-third of pregnant women are anaemic and many are severely anaemic. These women have an increased risk of PPH and are more likely to die if PPH occurs. There is an urgent need to identify ways to prevent severe postpartum bleeding in anaemic women. The WOMAN-2 trial will quantify the effects of TXA on postpartum bleeding in women with anaemia. Results: This statistical analysis plan (version 1.0; dated 22 February 2023) has been written based on information in the WOMAN-2 Trial protocol version 2.0, dated 30 June 2022. The primary outcome of the WOMAN-2 trial is the proportion of women with a clinical diagnosis of primary PPH. Secondary outcomes are maternal blood loss and its consequences (estimated blood loss, haemoglobin, haemodynamic instability, blood transfusion, signs of shock, use of interventions to control bleeding); maternal health and wellbeing (fatigue, headache, dizziness, palpitations, breathlessness, exercise tolerance, ability to care for her baby, health related quality of life, breastfeeding); and other health outcomes (deaths, vascular occlusive events, organ dysfunction, sepsis, side effects, time spent in higher level facility, length of hospital stay, and status of the baby). Conclusions: WOMAN-2 will provide reliable evidence about the effects of TXA in women with anaemia. Registration: WOMAN-2 was prospectively registered at the International Standard Randomised Controlled Trials registry ( ISRCTN62396133) on 07/12/2017 and ClinicalTrials.gov on 23/03/2018 ( NCT03475342).

Tranexamic acid for the prevention of blood loss after cesarean section: an updated systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

Tranexamic acid is a cost-effective intervention for the prevention of postpartum hemorrhage among women who undergo cesarean delivery, but the evidence to support its use is conflicting. We conducted this meta-analysis to evaluate the efficacy and safety of tranexamic acid in low- and high-risk cesarean deliveries.

DATA SOURCES

We searched MEDLINE (via PubMed), Embase, the Cochrane Library, ClinicalTrials.gov, and the World Health Organization International Clinical Trials Registry Platform portal from inception to April 2022 (updated October 2022 and February 2023) with no language restrictions. In addition, grey literature sources were also explored.

STUDY ELIGIBILITY CRITERIA

All randomized controlled trials that investigated the prophylactic use of intravenous tranexamic acid in addition to standard uterotonic agents among women who underwent cesarean deliveries in comparison with a placebo, standard treatment, or prostaglandins were included in this meta-analysis.

METHODS

We used the revised Cochrane Risk of Bias tool (RoB 2.0) to assess the quality of the included randomized controlled trials. RevMan 5.4 was used to conduct all statistical analyses using a random-effects model.

RESULTS

We included 50 randomized controlled trials (6 in only high-risk patients and 2 with prostaglandins as the comparator) that evaluated tranexamic acid in our meta-analysis. Tranexamic acid reduced the risk for blood loss >1000 mL, the mean total blood loss, and the need for blood transfusion in both low- and high-risk patients. Tranexamic acid was associated with a beneficial effect in the secondary outcomes, including a decline in hemoglobin levels and the need for additional uterotonic agents. Tranexamic acid increased the risk for nonthromboembolic adverse events but, based on limited data, did not increase the incidence of thromboembolic events. The administration of tranexamic acid before skin incision, but not after cord clamping, was associated with a large benefit. The quality of evidence was rated as low to very low for outcomes in the low-risk population and moderate for most outcomes in the high-risk subgroup.

CONCLUSION

Tranexamic acid may reduce the risk for blood loss in cesarean deliveries with a higher benefit observed in high-risk patients, but the lack of high-quality evidence precludes any strong conclusions. The administration of tranexamic acid before skin incision, but not after cord clamping, was associated with a large benefit. Additional studies, especially in the high-risk population and focused on evaluating the timing of tranexamic acid administration, are needed to confirm or refute these findings.

Patient Blood Management in Pregnancy

BACKGROUND

Patient blood management (PBM) is a multidisciplinary and patient-centered treatment approach, comprising the detection and treatment of anemia, the minimization of blood loss, and the rational use of allogeneic transfusions. Pregnancy, delivery, and the puerperium are associated with increased rates of iron deficiency and anemia, which correlates with worse maternal and fetal outcomes and places pregnant women at increased risk of obstetric hemorrhage.

SUMMARY

Early screening for iron deficiency before the onset of anemia, as well as the use of oral and intravenous iron to treat iron deficiency anemia, has been shown to be beneficial. Anemia in pregnancy and the puerperium should be treated according to a staged regimen, administering either iron alone or in combination with an off-label use of human recombinant erythropoietin in selected patients. This regimen should be tailored to the needs of each individual patient. Postpartum hemorrhage (PPH) accounts for up to one-third of maternal deaths in both developing and developed countries. Bleeding complications should be anticipated and blood loss reduced by interdisciplinary preventive measures and individually tailored care. It is recommended that facilities have a PPH algorithm, primarily focusing on prevention through use of uterotonics, but also incorporating early diagnosis of the cause of bleeding, optimization of hemostatic conditions, timely administration of tranexamic acid, and integration of point-of-care tests to support the guided substitution of coagulation factors, alongside standard laboratory tests. Additionally, cell salvage has proven beneficial and should be considered for various indications in obstetrics including hematologic disturbances, as well as various forms of placental disorders.

KEY MESSAGE

This article reviews PBM in pregnancy, delivery, and the puerperium. The concept comprises early screening and treatment of anemia and iron deficiency, a transfusion and coagulation algorithm during delivery, as well as cell salvage.

External Hemorrhage Control Techniques for Human Space Exploration: Lessons from the Battlefield

The past few decades of military experience have brought major advances in the prehospital care of patients with trauma. A focus on early hemorrhage control with aggressive use of tourniquets and hemostatic gauze is now generally accepted. This narrative literature review aims to discuss external hemorrhage control and the applicability of military concepts in space exploration. In space, environmental hazards, spacesuit removal, and limited crew training could cause significant time delays in providing initial trauma care. Cardiovascular and hematological adaptations to the microgravity environment are likely to reduce the ability to compensate, and resources for advanced resuscitation are limited. Any unscheduled emergency evacuation requires a patient to don a spacesuit, involves exposure to high G-forces upon re-entry into Earth's atmosphere, and costs a significant amount of time until a definitive care facility is reached. As a result, early hemorrhage control in space is critical. Safe implementation of hemostatic dressings and tourniquets seems feasible, but adequate training will be essential, and tourniquets are preferably converted to other methods of hemostasis in case of a prolonged medical evacuation. Other emerging approaches such as early tranexamic acid administration and more advanced techniques have shown promising results as well. For future exploration missions to the Moon and Mars, when evacuation is not possible, we look into what training or assistance tools would be helpful in managing the bleed at the point of injury.

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.

Tranexamic acid for the prevention of postpartum bleeding: Protocol for a systematic review and individual patient data meta-analysis

Tranexamic acid (TXA) reduces the risk of death and is recommended as a treatment for women with severe postpartum bleeding. There is hope that giving TXA shortly before or immediately after birth could prevent postpartum bleeding. Extending the use of TXA to prevent harmful postpartum bleeding could improve outcomes for millions of women; however we must carefully consider the balance of benefits and potential harms. This article describes the protocol for a systematic review and individual patient data (IPD) meta-analysis to assess the effectiveness and safety of TXA for preventing postpartum bleeding in all women giving birth, and to explore how the effects vary by underlying risk and other patient characteristics.   Methods: We will search for prospectively registered, randomised controlled trials involving 500 patients or more assessing the effects of TXA in women giving birth. Two authors will extract data and assess risk of bias. IPD data will be sought from eligible trials. Primary outcomes will be life-threatening bleeding and thromboembolic events. We will use a one-stage model to analyse the data. Subgroup analyses will be conducted to explore whether the effectiveness and safety of TXA varies by underlying risk, type birth, maternal haemoglobin (Hb), and timing of TXA. This protocol is registered on PROSPERO (CRD42022345775).  Conclusions: This systematic review and IPD meta-analysis will address important clinical questions about the effectiveness and safety of the use of TXA for the prevention of postpartum bleeding that cannot be answered reliably using aggregate data and will inform the decision of who to treat.   PROSPERO registration: CRD42022345775  Keywords   Anti-fibrinolytics; Tranexamic acid; childbirth; postpartum haemorrhage; meta-analysis.

Development of a national out-of-hospital transfusion protocol: a modified RAND Delphi study

BACKGROUND

Early resuscitation with blood components or products is emerging as best practice in selected patients with trauma and medical patients; as a result, out-of-hospital transfusion (OHT) programs are being developed based on limited and often conflicting evidence. This study aimed to provide guidance to Canadian critical care transport organizations on the development of OHT protocols.

METHODS

The study period was July 2021 to June 2022. We used a modified RAND Delphi process to achieve consensus on statements created by the study team guiding various aspects of OHT in the context of critical care transport. Purposive sampling ensured representative distribution of participants in regard to geography and relevant clinical specialties. We conducted 2 written survey Delphi rounds, followed by a virtual panel discussion (round 3). Consensus was defined as a median score of at least 6 on a Likert scale ranging from 1 ("Definitely should not include") to 7 ("Definitely should include"). Statements that did not achieve consensus in the first 2 rounds were discussed and voted on during the panel discussion.

RESULTS

Seventeen subject experts participated in the study, all of whom completed the 3 Delphi rounds. After the study process was completed, a total of 39 statements were agreed on, covering the following domains: general oversight and clinical governance, storage and transport of blood components and products, initiation of OHT, types of blood components and products, delivery and monitoring of OHT, indications for and use of hemostatic adjuncts, and resuscitation targets of OHT.

INTERPRETATION

This expert consensus document provides guidance on OHT best practices. The consensus statements should support efficient and safe OHT in national and international critical care transport programs.

The CRYOSTAT2 trial: The rationale and study protocol for a multi-Centre, randomised, controlled trial evaluating the effects of early high-dose cryoprecipitate in adult patients with major trauma haemorrhage requiring major haemorrhage protocol activation

OBJECTIVES

To describe the protocol for a multinational randomised, parallel, superiority trial, in which patients were randomised to receive early high-dose cryoprecipitate in addition to standard major haemorrhage protocol (MHP), or Standard MHP alone.

BACKGROUND

Blood transfusion support for trauma-related major bleeding includes red cells, plasma and platelets. The role of concentrated sources of fibrinogen is less clear and has not been evaluated in large clinical trials. Fibrinogen is a key pro-coagulant factor that is essential for stable clot formation. A pilot trial had demonstrated that it was feasible to deliver cryoprecipitate as a source of fibrinogen within 90 min of admission.

METHODS

Randomisation was via opaque sealed envelopes held securely in participating Emergency Departments or transfusion laboratories. Early cryoprecipitate, provided as 3 pools (equivalent to 15 single units of cryoprecipitate or 6 g fibrinogen supplementation), was transfused as rapidly as possible, and started within 90 min of admission. Participants in both arms received standard treatment defined in the receiving hospital MHP. The primary outcome measure was all-cause mortality at 28 days. Symptomatic thrombotic events including venous thromboembolism and arterial thrombotic events (myocardial infarction, stroke) were collected from randomisation up to day 28 or discharge from hospital. EQ5D-5Land Glasgow Outcome Score were completed at discharge and 6 months. All analyses will be performed on an intention to treat basis, with per protocol sensitivity analysis.

RESULTS

The trial opened for recruitment in June 2017 and the final patient completed follow-up in May 2022.

DISCUSSION

This trial will provide firmer evidence to evaluate the effectiveness and cost-effectiveness of early high-dose cryoprecipitate alongside the standard MHP in major traumatic haemorrhage.

A self-gelling powder based on polyacrylic acid/polyacrylamide/quaternate chitosan for rapid hemostasis

In order to improve the hemostatic effect of the hemostatic dressing for non-compressible wounds, unknown bleeding points and irregularly shaped wounds, a self-gelling hemostasis powder based on polyacrylic acid/polyacrylamide/quaternate chitosan (PAA/PAM/QCS) is prepared in this study. When in contact with water, the PAA/PAM/QCS can fuse and rapidly form a stable hydrogel in a short time (< 0.25 min). The PAA/PAM ratio is the main parameter that modulates the formation of the self-gel. The PAA/PAM self-gel can be formed only when the PAA/PAM ratio is 5:5, and the introduction of QCS does not influence the self-gelling behaviors and hydrogel stability. Moreover, the PAA/PAM/QCS self-gel shows good adhesive properties on wet tissue surfaces. In addition, the introduction of QCS improves the antibacterial activity of the self-gelling hemostasis powder. Furthermore, the prepared PAA/PAM/QCS powder can rapidly adsorb lots of blood, aggregate blood cells and platelets. The hemostatic results in vivo show that PAA/PAM/QCS powder is superior to the control group and commercial product groups (chitosan powder) with performance similar to hemostatic zeolite in terms of the amount of bleeding and hemostatic time. Therefore, the PAA/PAM/QCS self-gelling powder shows great application prospects for rapid hemostasis.

Prehospital tranexamic acid for trauma victims

The public enquiry into the mass casualty incident at the Manchester Arena in the UK in which 23 people died and over 1000 were injured, identified the need for timely intramuscular administration of tranexamic acid to trauma patients. Since then, a number of studies and trials have been carried out and UK paramedics are now authorized to give intramuscular tranexamic acid in the pre-hospital setting. In Japan, pre-hospital administration by emergency life-saving technicians is not yet authorized, despite the fact that tranexamic acid was invented by Japanese scientists. In Japan, the need for the pre-hospital administration of tranexamic acid has been raised on several occasions, where a patient died from traumatic bleeding prior to hospital admission. This paper summarizes the evidence on the use of tranexamic acid in patients with traumatic bleeding, including new evidence on the intramuscular route.

Tranexamic acid for gastrointestinal bleeding: can a reduction in the risk of death be discounted? A systematic review and meta-analysis of individual patient data from 64 724 bleeding patients

OBJECTIVES

HALT-IT was an international, randomised trial which assessed the effects of tranexamic acid (TXA) in 12 009 patients with gastrointestinal (GI) bleeding. The results found no evidence that TXA reduces death. It is widely accepted that results of trials should be interpreted in the context of other relevant evidence. We conducted a systematic review and individual patient data (IPD) meta-analysis to assess if the results of HALT-IT are compatible with evidence for TXA in other bleeding conditions.

DESIGN

Systematic review and IPD meta-analysis of randomised trials involving ≥5000 patients assessing TXA for bleeding. We searched our Antifibrinolytics Trials Register on 1 November 2022. Two authors extracted data and assessed risk of bias.

DATA SYNTHESIS

We used a one-stage model to analyse IPD in a regression model stratified by trial. We assessed heterogeneity of the effect of TXA on death within 24 hours and vascular occlusive events (VOEs).

RESULTS

We included IPD for 64 724 patients from four trials involving patients with traumatic, obstetric and GI bleeding. Risk of bias was low. There was no evidence for heterogeneity between trials for the effect of TXA on death or for the effect of TXA on VOEs. TXA reduced the odds of death by 16% (OR=0.84, 95% CI: 0.78 to 0.91, p<0.0001; p-heterogeneity=0.40). In patients treated within 3 hours of bleeding onset, TXA reduced the odds of death by 20% (0.80, 0.73 to 0.88, p<0.0001; p-heterogeneity=0.16). TXA did not increase the odds of VOEs (0.94, 0.81 to 1.08, p for effect=0.36; p-heterogeneity=0.27).

CONCLUSIONS

There is no evidence for statistical heterogeneity between trials assessing the effect of TXA on death or VOEs in different bleeding conditions. When the HALT-IT results are considered in the context of other evidence, a reduction in the risk of death cannot be discounted.

TRIAL REGISTRATION NUMBER

PROSPERO CRD42019128260.Cite Now.

Should pre-hospital intramuscular tranexamic acid be given to trauma patients at risk of significant haemorrhage?

There are situations in the pre-hospital setting where gaining intravenous or intraosseous access is impossible or delayed. This can delay the administration of tranexamic acid to bleeding trauma patients, which may reduce its effectiveness. We sought to investigate whether some patients would benefit from early administration of tranexamic acid via the intramuscular route. Relevant observational and interventional studies were identified and summarised using a BestBET format. The current evidence supports clinicians considering intramuscular tranexamic acid in trauma patients at risk of haemorrhage when there may be significant delay in administration via intravenous or intraosseous routes.

Major haemorrhage: past, present and future

Major haemorrhage is a leading cause of morbidity and mortality worldwide. Successful treatment requires early recognition, planned responses, readily available resources (such as blood products) and rapid access to surgery or interventional radiology. Major haemorrhage is often accompanied by volume loss, haemodilution, acidaemia, hypothermia and coagulopathy (factor consumption and fibrinolysis). Management of major haemorrhage over the past decade has evolved to now deliver a 'package' of haemostatic resuscitation including: surgical or radiological control of bleeding; regular monitoring of haemostasis; advanced critical care support; and avoidance of the lethal triad of hypothermia, acidaemia and coagulopathy. Recent trial data advocate for a more personalised approach depending on the clinical scenario. Fresh frozen plasma should be given as early as possible in major trauma in a 1:1 ratio with red blood cells until the results of coagulation tests are available. Tranexamic acid is a cheap, life-saving drug and is advocated in major trauma, postpartum haemorrhage and surgery, but not in patients with gastrointestinal bleeding. Fibrinogen levels should be maintained > 2 g.l^-1 in postpartum haemorrhage and > 1.5 g.l^-1 in other haemorrhage. Improving outcomes after major traumatic haemorrhage is now driving research to include extending blood-product resuscitation into prehospital care.

Systemic hemostatic agents initiated in trauma patients in the pre-hospital setting: a systematic review

Purpose

The effect of systemic hemostatic agents initiated during pre-hospital care of severely injured patients with ongoing bleeding or traumatic brain injury (TBI) remains controversial. A systematic review and meta-analysis was therefore conducted to assess the effectiveness and safety of systemic hemostatic agents as an adjunctive therapy in people with major trauma and hemorrhage or TBI in the context of developing the Italian National Institute of Health guidelines on major trauma integrated management.

Methods

PubMed, Embase, and Cochrane Library databases were searched up to October 2021 for studies that investigated pre-hospital initiated treatment with systemic hemostatic agents. The certainty of evidence was evaluated with the Grading of Recommendations Assessment, Development, and Evaluation approach, and the quality of each study was determined with the Cochrane risk-of-bias tool. The primary outcome was overall mortality, and secondary outcomes included cause-specific mortality, health-related quality of life, any adverse effects and blood product use, hemorrhage expansion, and patient-reported outcomes.

Results

Five trials of tranexamic acid (TXA) met the inclusion criteria for this meta-analysis. With a high certainty of evidence, when compared to placebo TXA reduced mortality at 24 h (relative risk = 0.83, 95% confidence interval = 0.73–0.94) and at 1 month among trauma patients (0.91, 0.85–0.97). These results depend on the subgroup of patients with significant hemorrhage because in the subgroup of TBI there are no difference between TXA and placebo. TXA also reduced bleeding death and multiple organ failure whereas no difference in health-related quality of life.

Conclusion

Balancing benefits and harms, TXA initiated in the pre-hospital setting can be used for patients experiencing major trauma with significant hemorrhage since it reduces the risk of mortality at 24 h and one month with no difference in terms of adverse effects when compared to placebo. Considering the subgroup of severe TBI, no difference in mortality rate was found at 24 h and one month. These results highlight the need to conduct future studies to investigate the role of other systemic hemostatic agents in the pre-hospital settings.

State-by-state estimates of avoidable trauma mortality with early and liberal versus delayed or restricted administration of tranexamic acid

OBJECTIVE

Early administration of tranexamic acid (TXA) has been shown to save lives in trauma patients, and some U.S. emergency medical systems (EMS) have begun providing this therapy prehospital. Treatment protocols vary from state to state: Some offer TXA broadly to major trauma patients, others reserve it for patients meeting vital sign criteria, and still others defer TXA entirely pending a hospital evaluation. The purpose of this study is to compare the avoidable mortality achievable under each of these strategies, and to report on the various approaches used by EMS.

METHODS

We used the National Center for Health Statistics Underlying Cause of Death data to identify a TXA-naïve population of trauma patients who died from 2007 to 2012 due to hemorrhage. We estimated the proportion of deaths where the patient was hypotensive or tachycardic using the National Trauma Data Bank. We used avoidable mortality risk ratios from the landmark CRASH 2 study to calculate lives saved had TXA been given within one hour of injury based on a clinician's gestalt the patient was at risk for significant hemorrhage; had it been reserved only for hypotensive or tachycardic patients; or had it been given between hours one to three of injury, considered here as a surrogate for deferring the question to the receiving hospital.

RESULTS

Had TXA been given within 1 hour of injury, an average of 3409 deaths per year could have been averted nationally. Had TXA been given between one and three hours after injury, 2236 deaths per year could have been averted. Had TXA only been given to either tachycardic or hypotensive trauma patients, 1371 deaths per year could have been averted. Had TXA only been given to hypotensive trauma patients, 616 deaths per year could have been averted. Similar trends are seen at the individual state level. A review of EMS practices found 15 statewide protocols that allow EMS providers to administer TXA for trauma.

CONCLUSION

Providing early TXA to persons at risk of significant hemorrhage has the potential to prevent many deaths from trauma, yet most states do not offer it in statewide prehospital treatment protocols.

Tranexamic acid for the prevention of blood loss after cesarean among women with twins: a secondary analysis of the TRAnexamic Acid for Preventing Postpartum Hemorrhage Following a Cesarean Delivery randomized clinical trial

BACKGROUND

Although prophylactic tranexamic acid administration after cesarean delivery resulted in a lower incidence of calculated estimated blood loss of >1000 mL or red cell transfusion by day 2, its failure to reduce the incidence of hemorrhage-related secondary clinical outcomes (TRAnexamic Acid for Preventing Postpartum Hemorrhage Following a Cesarean Delivery trial) makes its use questionable. The magnitude of its effect may differ in women at higher risk of blood loss, including those with multiple pregnancies.

OBJECTIVE

This study aimed to compare the effect of tranexamic acid vs placebo to prevent blood loss after cesarean delivery among women with multiple pregnancies.

STUDY DESIGN

This was a secondary analysis of the TRAnexamic Acid for Preventing Postpartum Hemorrhage Following a Cesarean Delivery trial data, a double-blind, randomized controlled trial from March 2018 to January 2020 in 27 French maternity hospitals, that included 319 women with multiple pregnancies. Women with a cesarean delivery before or during labor at ≥34 weeks of gestation were randomized to receive intravenously 1 g of tranexamic acid (n=160) or placebo (n=159), both with prophylactic uterotonics. The primary outcome was a calculated estimated blood loss of >1000 mL or a red blood cell transfusion by 2 days after delivery. The secondary outcomes included clinical and laboratory blood loss measurements.

RESULTS

Of the 4551 women randomized in this trial, 319 had a multiple pregnancy and cesarean delivery, and 298 (93.4%) had primary outcome data available. This outcome occurred in 62 of 147 women (42.2%) in the tranexamic acid group and 67 of 152 (44.1%) receiving placebo (adjusted risk ratio, 0.97; 95% confidence interval, 0.68-1.38; P=.86). No significant between-group differences occurred for any hemorrhage-related clinical outcomes: gravimetrically estimated blood loss, provider-assessed clinically significant hemorrhage, additional uterotonics, postpartum blood transfusion, arterial embolization, and emergency surgery (P>.05 for all comparisons).

CONCLUSION

Among women with a multiple pregnancy and cesarean delivery, prophylactic tranexamic acid did not reduce the incidence of any blood loss-related outcomes.

Guideline No. 431: Postpartum Hemorrhage and Hemorrhagic Shock

OBJECTIVE

This guideline aims to provide evidence for prevention, recognition, and treatment of postpartum hemorrhage including severe hemorrhage leading to hemorrhagic shock.

TARGET POPULATION

All pregnant patients.

BENEFITS, HARMS, AND COSTS

Appropriate recognition and treatment of postpartum hemorrhage can prevent serious morbidity while reducing costs to the health care system by minimizing more costly interventions and length of hospital stays.

EVIDENCE

Medical literature, PubMed, ClinicalTrials.gov, the Cochrane Database, and grey literature were searched for articles, published between 2012 and 2021, on postpartum hemorrhage, uterotonics, obstetrical hemorrhage, and massive hemorrhage protocols.

VALIDATION METHODS

The authors rated the quality of evidence and strength of recommendations using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. See online Appendix A (Tables A1 for definitions and A2 for interpretations of strong and conditional [weak] recommendations).

INTENDED AUDIENCE

All members of the health care team who care for labouring or postpartum women, including, but not restricted to, nurses, midwives, family physicians, obstetricians, and anesthesiologists.

RECOMMENDATIONS

Total Hip Arthroplasty Patients with Distinct Postoperative Fibrinolytic Phenotypes Require Different Antifibrinolytic Strategies

Bleeding patients exhibit different fibrinolytic phenotypes after injury, and the universal use of tranexamic acid (TXA) is doubted. We aimed to evaluate the efficacy of postoperative antifibrinolytic treatment in total hip arthroplasty (THA) patients with different fibrinolytic phenotypes. A retrospective analysis was conducted in 238 patients who underwent THA. Patients were divided into two groups by different fibrinolytic phenotypes (non-fibrinolytic shutdown and fibrinolytic shutdown), determined by the LY30 level on postoperative day 1 (POD1). The two groups were further stratified into four sub-groups based on different postoperative TXA regimens (Group A received no TXA postoperatively, while Group B did). Hidden blood loss (HBL), decline of hemoglobin (ΔHb), D-dimer (D-D), fibrinogen/fibrin degradation product (FDP), prothrombin time (PT), activated partial thromboplastin time (APTT), and demographics were collected and compared. The clinical baseline data were comparable between the studied groups. In patients who presented non-fibrinolytic shutdown postoperatively, Group B suffered significantly lower HBL and ΔHb than Group A on POD3 and POD5. In patients who presented postoperative fibrinolytic shutdown, Group B failed to benefit from the postoperative administration of TXA when compared to Group A. No difference was found in postoperative levels of D-D, FDP, PT, and APTT. Postoperative antifibrinolytic therapy is beneficial for THA patients who presented non-fibrinolytic shutdown postoperatively, while the efficacy and necessity should be considered with caution in those with fibrinolytic shutdown. LY30 is a promising parameter to distinguish different fibrinolytic phenotypes and guide TXA administration. However, further prospective studies are needed to confirm these findings.

Intramuscular Tranexamic Acid Administration on the Battlefield

Background

Tranexamic acid (TXA) is routinely administered intravenously (IV) and intraosseously (IO) in response to exsanguination.

Case

This report describes a patient who sustained multiple high-powered rifle gunshot wounds that received battlefield-environment intramuscular (IM) administration of TXA due to inability to obtain IV / IO access. This case represents the unlikely positive outcome in the setting of multiple remarkable obstacles, which may have been ameliorated by novel administration of TXA.

Conclusion

Cases of IM TXA administration as a primary intervention are not well represented in the current body of medical literature. This case report highlights a clinical scenario where IM TXA was utilized as part of first-line treatment that led to a positive clinical outcome. Although IM TXA is not yet endorsed by current trauma guidelines, this case suggests that IM route administration of TXA should be further investigated. If indeed IM administration of TXA proves just as efficacious as alternative routes, this would hold considerable advantageous implications for austere situations were sterility and IV / IO placement are impractical. This would also represent another avenue by which to decrease the time-to-TXA for patients, allowing sooner correction of hemorrhage and trauma-associated coagulopathy.