Tranexamic acid for post-partum haemorrhage: What, who and when.

Tranexamic acid reduces bleeding by inhibiting the breakdown of blood clots. It is cost-effective and heat-stable with a long shelf life. In the WOMAN trial, tranexamic acid reduced deaths due to bleeding with no increase in thromboembolic events. The effect was greatest when women received tranexamic acid within 3 h of childbirth (RR = 0.69, 95% CI 0.52-0.91). The WHO recommends that women with post-partum haemorrhage receive 1 g tranexamic acid intravenously as soon as possible after giving birth, followed by a second dose if bleeding continues after 30 min or restarts within 24 h since the first dose. Urgent treatment is critical because women with post-partum haemorrhage bleed to death quickly, and tranexamic acid is most effective when given early. Evidence suggests there is no benefit when the drug is given more than 3 h after bleeding onset. Alternative routes of administration and use of tranexamic acid in the prevention of post-partum haemorrhage are research priorities

Tranexamic Acid Treatment for Trauma Victims.

Worldwide, traumatic injury is responsible for over 5 million deaths per year, the majority due to exsanguination and head injury. The antifibrinolytic drug tranexamic acid is the only drug proven to reduce deaths after traumatic injury. Several large randomized controlled trials have provided high-quality evidence of its effectiveness and safety in trauma patients. Early tranexamic acid reduces deaths on the day of the injury in polytrauma patients and patients with isolated traumatic brain injury by around 20%. Treatment is time critical; for patients to benefit, tranexamic acid must be given as soon as possible after injury. Intramuscular administration is well tolerated and rapidly absorbed, with the potential to reduce time to treatment. Because the proportional reduction in bleeding death with tranexamic acid does not vary by baseline risk, a wide range of trauma patients stands to benefit. There are far more low-risk trauma patients than high-risk patients, with a substantial proportion of bleeding deaths in the low-risk group. As such, treatment should not be limited to patients with severe traumatic hemorrhage. We must give paramedics and physicians the confidence to treat a far wider range of trauma patients while emphasizing the importance of early treatment

A nested randomised trial of the effect of tranexamic acid on intracranial haemorrhage and infarction in traumatic brain injury (CRASH-3 trial intracranial bleeding mechanistic study): Statistical analysis plan [version 2; peer review: 2 approved, 1 approved with reservations]

Background: The CRASH-3 trial is a randomised trial on the effect of tranexamic acid (TXA) on death and disability in traumatic brain injury (TBI). The CRASH-3 intracranial bleeding mechanistic study (IBMS) is a randomised trial nested within the CRASH-3 trial to examine the effect of TXA on intracranial bleeding and infarction. Methods: Patients eligible for the CRASH-3 trial, with a GCS of 12 or less or intracranial bleeding on a pre-randomisation CT scan are eligible for the IBMS. The occurrence of intracranial bleeding, infarction, haemorrhagic oedematous lesions, mass effect and haemorrhage evacuation is examined within 28 days of randomisation using routinely collected brain scans. The primary outcome is the volume of intra-parenchymal bleeding in patients randomised within three hours of injury (adjusted for prognostic covariates). Secondary outcomes include a composite “poor” outcome, progressive and new intracranial bleeding, intracranial bleeding after neurosurgery and cerebral infarcts seen up to 28 days post-randomisation. All outcomes will be compared between treatment groups. Statistical analyses: The primary outcome will be analysed using a covariate adjusted linear mixed model. The same analysis will be done separately for patients who undergo haemorrhage evacuation post-randomisation. We will express the effect of TXA on the composite outcome, new and progressive bleeding using relative risks and 95% CIs, and on cerebral infarcts using hazard ratios and 95% CIs. We will conduct sensitivity analyses assuming missing data are MCAR or MNAR. Conclusion: The IBMS will provide information on the mechanism of action of TXA in TBI. This pre-specified statistical analysis plan is a technical extension of the published protocol. Trial registration: The CRASH-3 trial was prospectively registered at the International Standard Randomised Controlled Trials registry (19 July 2011) and ClinicalTrials.gov (25 July 2011). The registries were updated with details for the IBMS on 20 December 2016

A nested randomised trial of the effect of tranexamic acid on intracranial haemorrhage and infarction in traumatic brain injury (CRASH-3 trial intracranial bleeding mechanistic study): Statistical analysis plan.

Background: The CRASH-3 trial is a randomised trial on the effect of tranexamic acid (TXA) versus placebo on death and disability in traumatic brain injury (TBI). The CRASH-3 intracranial bleeding mechanistic study (IBMS) is a randomised trial nested within the CRASH-3 trial to examine the effect of TXA versus placebo on intracranial bleeding and infarction. Methods: Patients eligible for the CRASH-3 trial, with a GCS of 12 or less or intracranial bleeding on a pre-randomisation CT scan are eligible for the IBMS. The occurrence of intracranial bleeding, infarction, haemorrhagic oedematous lesions, mass effect and haemorrhage evacuation is examined within 28 days of randomisation using routinely collected brain scans. The primary outcome is the volume of intra-parenchymal bleeding in patients randomised within three hours of injury (adjusted for prognostic covariates). Secondary outcomes include a composite "poor" outcome, progressive and new intracranial bleeding, intracranial bleeding after neurosurgery and cerebral infarcts seen up to 28 days post-randomisation. All outcomes will be compared between treatment groups. Statistical analyses: The primary outcome will be analysed using a covariate adjusted linear mixed model. The same analysis will be done separately for patients who undergo haemorrhage evacuation post-randomisation. We will express the effect of TXA on the composite outcome, new and progressive bleeding using relative risks and 95% CIs, and on cerebral infarcts using hazard ratios and 95% CIs. We will conduct sensitivity analyses assuming missing data are MCAR or MNAR. Conclusion: The IBMS will provide information on the mechanism of action of TXA in TBI. This pre-specified statistical analysis plan is a technical extension of the published protocol. Trial registration: The CRASH-3 trial was prospectively registered at the International Standard Randomised Controlled Trials registry (19 July 2011) and ClinicalTrials.gov (25 July 2011). The registries were updated with details for the IBMS on 20 December 2016

Effects of tranexamic acid treatment in severely and non-severely injured trauma patients.

BACKGROUND: Urgent treatment with tranexamic acid (TXA) reduces bleeding deaths but there is disagreement about which patients should be treated. We examine the effects of TXA treatment in severely and non-severely injured trauma patients. STUDY DESIGN AND METHODS: We did an individual patient data meta-analysis of randomized trials with over 1000 trauma patients that assessed the effects of TXA on survival. We defined the severity of injury according to characteristics at first assessment: systolic blood pressure of less than 90 mm Hg and a heart rate greater than 120 beats per minute or Glasgow Coma Scale score of less than nine or any GCS with one or more fixed dilated pupils. The primary measure was survival on the day of the injury. We examined the effect of TXA on survival in severely and non-severely injured patients and how these effects vary with the time from injury to treatment. RESULTS: We obtained data for 32,944 patients from two randomized trials. Tranexamic acid significantly increased survival on the day of the injury (OR = 1.22, 95% CI 1.11-1.34; p < .01). The effect of tranexamic acid on survival in non-severely injured patients (OR = 1.25, 1.03-1.50) was similar to that in severely injured patients (OR = 1.22, 1.09-1.37) with no significant heterogeneity (p = .87). In severely and non-severely injured pateints, treatment within the first hour after injury was the most effective. DISCUSSION: Early tranexamic acid treatment improves survival in both severely and non-severely injured trauma patients. Its use should not be restricted to the severely injured

Accuracy of time to treatment estimates in the CRASH-3 clinical trial: impact on the trial results.

BACKGROUND: Early treatment with tranexamic acid may reduce deaths after traumatic brain injury (TBI). In mild and moderate TBI, there is a time to treatment interaction, with early treatment being most beneficial. Time to treatment was recorded by clinicians and is subject to error. Using monitoring data from the CRASH-3 trial, we examine the impact of errors in time to treatment on estimated treatment effects. METHODS: The CRASH-3 trial was a randomised trial of the effect of tranexamic acid on death and vascular occlusive events in 12,737 TBI patients. This analysis includes the 8107 patients with a Glasgow coma scale score of 9 to 15 since previous analyses showed that these patients benefit most from early treatment. Clinician-recorded time to treatment was checked against ambulance and hospital records for 1368/12,737 (11%) patients. Patients who died were preferentially selected for monitoring and we monitored 36% of head injury deaths. We describe measurement errors using Bland-Altman graphs. We model the effect of tranexamic acid on head injury death using logistic regression with a time-treatment interaction term. We use regression calibration, multiple imputation and Bayesian analysis to estimate the impact of time to treatment errors. RESULTS: Clinicians rounded times to the nearest half or full hour in 66% of cases. Monitored times were also rounded and were identical to clinician times in 63% of patients. Times were underestimated by an average of 9 min (95% CI -?85, 66). There was more variability between clinician-recorded and monitored times in low- and middle-income countries than in high-income countries. The treatment effect estimate at 1 h was greater for monitored times OR?=?0.61 (95% CI 0.47, 0.81) than for clinician-recorded times OR?=?0.63 (95% CI 0.48, 0.83). All three adjustment methods gave similar time to treatment interactions. For Bayesian methods, the treatment effect at 1 h was OR?=?0.58 (95% CI 0.43, 0.78). Using monitored times increased the time-treatment interaction term from 1.15 (95% CI 1.03, 1.27) to 1.16 (95% CI 1.05, 1.28). CONCLUSIONS: Accurate estimation of time from injury to treatment is challenging, particularly in low resource settings. Adjustment for known errors in time to treatment had minimal impact on the trial results. TRIAL REGISTRATION: ClinicalTrials.gov NCT01402882 . Registered on 25 July 2011

Risk factors for blood transfusion in traumatic and postpartum hemorrhage patients: Analysis of the CRASH-2 and WOMAN trials.

BACKGROUND: Hemorrhage is a leading cause of death after trauma and childbirth. In response to severe hemorrhage, bleeding patients often receive transfusions of red blood cells, plasma, platelets, or other blood components. We examined risk factors for transfusion in acute severe bleeding in two trials of over 20,000 patients to better understand factors associated with transfusion likelihood. STUDY DESIGN AND METHODS: We conducted a cohort analysis of data from the CRASH-2 and WOMAN trials, two multinational trials that recruited patients with traumatic and postpartum hemorrhage, respectively. For each trial, we examined the effect of 10 factors on blood transfusion likelihood. Univariate and multivariate Poisson regressions were used to analyze the relationship between risk factors and blood transfusion. RESULTS: Of the 20,207 traumatic hemorrhage patients, 10,232 (51%) received blood components. Of the 20,060 women with postpartum hemorrhage, 10,958 (55%) received blood components. For patients who suffered from traumatic hemorrhage, those greater than three hours from injury to hospitalization were more likely to be transfused (ARR 1.37; 95% CI, 1.20-1.56). Postpartum hemorrhage patients had an increased likelihood of transfusion if they gave birth outside the hospital (ARR 1.30; 95% CI 1.22-1.39), gave birth more than three hours before hospitalization (ARR 1.09; 95% CI 1.01-1.17), had a Caesarean section (ARR 1.16; 95% CI 1.08-1.25), and if they had any identifiable causes of hemorrhage other than uterine atony. CONCLUSION: Several risk factors are associated with an increased likelihood of transfusion in traumatic and postpartum hemorrhage patients. Altering modifiable factors, by reducing time from injury or childbirth to hospitalization, for example, might be able to reduce transfusions and their complications. TRIAL REGISTRATION: CRASH-2 is registered as ISRCTN86750102, ClinicalTrials.gov NCT00375258 and South African Clinical Trial Register DOH-27-0607-1919. WOMAN is registered as ISRCTN76912190, ClinicalTrials.gov NCT00872469, PACTR201007000192283, and EudraCT number 2008-008441-38

WOMAN-2 Pilot Study Data

Data and supporting material produced as part of a pilot study to test outcome questions for the WOMAN-2 trial of tranexamic acid for the prevention of postpartum haemorrhage. This pilot study was conducted in one hospital which will also be conducting the WOMAN-2 Trial in Pakistan. The pilot study population included participants similar to those to be included in the WOMAN-2 Trial: women who are anaemic, and having given birth. Participants took part in an interview which included answering questions from the draft participant reported outcomes questionnaire. A small subset of participants enrolled in this pilot study also took part in a cognitive interview directly following the questionnaire to learn how they understood the questions. Each row of the dataset table represents data for an individual participant

Tranexamic acid quantification in human whole blood using liquid samples or volumetric absorptive microsampling devices.

Background: Recent clinical trials demonstrate the benefits of the antifibrinolytic drug tranexamic acid but its pharmacokinetics remain to be investigated more in depth. Although pharmacokinetics studies are usually performed with plasma, volumetric absorptive microsampling devices allow us to analyze dried whole blood samples with several advantages. Materials & methods: High-sensitivity LC-MS/MS methods for the quantification of tranexamic acid in human whole blood using liquid samples or dry samples on volumetric absorptive microsampling devices were developed and validated based on International Association from Therapeutic Drug Monitoring and Clinical Toxicology, European Medicines Agency and US FDA guidance. Conclusion: The method performances were excellent across the range of clinically relevant concentrations. The stability of tranexamic acid in blood samples stored up to 1 month at +50°C was demonstrated. The methods' suitability was confirmed with clinical samples