Fibrinolysis and tranexamic acid: mechanistic principles

Efficacy and safety of single- and double-dose intravenous tranexamic acid in hip and knee arthroplasty: a systematic review and meta-analysis

OBJECTIVE

With the increasing prevalence of osteoarthritis of the hip and knee, total joint replacement, the end-stage treatment, provides pain relief and restoration of function, but is often associated with massive blood loss. Tranexamic acid (TXA) has been reported to reduce perioperative blood loss in hip or knee arthroplasty. However, the optimal dose of TXA administration remains controversial. Therefore, we performed a meta-analysis combining data from 5 trials comparing the efficacy and safety of one fixed dose of 1 g intravenously administered TXA with two doses of 1 g each administered intravenously for hip or knee arthroplasty.

METHODS

PubMed, Medline, Embase, Web of Science, and The Cochrane Library were searched from January 2000 to February 2023. Our meta-analysis included randomized controlled trials and cohort studies comparing the efficacy and safety of different doses of intravenous TXA (IV-TXA) for THA or TKA. The observation endpoints included total blood loss, postoperative hemoglobin drop, blood transfusion rate, length of hospital stay, incidence of deep venous thrombosis (DVT), and incidence of pulmonary embolism (PE). Meta-analysis was performed according to Cochrane's guidelines and PRISMA statement. The Danish RevMan5.3 software was used for data merging.

RESULTS

Five cohort studies involving 5542 patients met the inclusion criteria. Our meta-analysis showed that the two groups were significantly higher in total blood loss (mean difference (MD) = - 65.60, 95% confidence interval (CI) [- 131.46, 0.26], P = 0.05); blood transfusion rate (risk difference (RD) = 0.00, 95% CI [- 0.01, 0.02], P = 0.55); postoperative hemoglobin (MD = 0.02, 95% CI [- 0.09, 0.13], P = 0.31); postoperative hospital stay days (MD = - 0.13), 95% CI [- 0.35, 0.09], P = 0.25); DVT (RD = 0.00, 95% CI [- 0.00, 0.01], P = 0.67); PE (RD = 0.00, 95% CI [- 0.01, 0.00], P = 0.79). There was some inherent heterogeneity due to variance in sample size across each major study.

CONCLUSION

1 dose of 1 g and 2 doses of 1 g IV-TXA each time have similar effects on reducing blood loss, blood transfusion rate, postoperative hemoglobin level, and postoperative hospital stay after TKA or THA, without increasing the risk of postoperative complications risk. For patients at high risk of thromboembolic events, one dose of 1 g TXA throughout surgery may be preferred. However, higher-quality RCT is needed to explore the optimal protocol dose to recommend the widespread use of TXA in total joint arthroplasty. Trial registration We conducted literature selection, eligibility criteria evaluation, data extraction and analysis on the research program registered in Prospero (CRD42023405387) on March 16, 2023.

Protocol for a multicentre prehospital randomised controlled trial investigating tranexamic acid in severe trauma: the PATCH-Trauma trial

INTRODUCTION

Haemorrhage causes most preventable prehospital trauma deaths and about a third of in-hospital trauma deaths. Tranexamic acid (TXA), administered soon after hospital arrival in certain trauma systems, is an effective therapy in preventing or managing acute traumatic coagulopathy. However, delayed administration of TXA appears to be ineffective or harmful. The effectiveness of prehospital TXA, incidence of thrombotic complications, benefit versus risk in advanced trauma systems and the mechanism of benefit remain uncertain.

METHODS AND ANALYSIS

The Pre-hospital Anti-fibrinolytics for Traumatic Coagulopathy and Haemorrhage (The PATCH-Trauma study) is comparing TXA, initiated prehospital and continued in hospital over 8 hours, with placebo in patients with severe trauma at risk of acute traumatic coagulopathy. We present the trial protocol and an overview of the statistical analysis plan. There will be 1316 patients recruited by prehospital clinicians in Australia, New Zealand and Germany. The primary outcome will be the eight-level Glasgow Outcome Scale Extended (GOSE) at 6 months after injury, dichotomised to favourable (GOSE 5-8) and unfavourable (GOSE 1-4) outcomes, analysed using an intention-to-treat (ITT) approach. Secondary outcomes will include mortality at hospital discharge and at 6 months, blood product usage, quality of life and the incidence of predefined adverse events.

ETHICS AND DISSEMINATION

The study was approved by The Alfred Hospital Research and Ethics Committee in Victoria and also approved in New South Wales, Queensland, South Australia, Tasmania and the Northern Territory. In New Zealand, Northern A Health and Disability Ethics Committee provided approval. In Germany, Witten/Herdecke University has provided ethics approval. The PATCH-Trauma study aims to provide definitive evidence of the effectiveness of prehospital TXA, when used in conjunction with current advanced trauma care, in improving outcomes after severe injury.

TRIAL REGISTRATION NUMBER

NCT02187120.