Tranexamic acid administration for anatomic and reverse total shoulder arthroplasty: a systematic review and meta-analysis

Background

Tranexamic acid (TXA) has been shown to reduce perioperative blood loss and risk of blood transfusion. Evidence establishing its efficacy in total shoulder arthroplasty (TSA) is limited. The current study evaluated the effect of TXA on perioperative blood loss and transfusion risk after TSA.

Methods

A systematic review and meta-analysis of TXA administration for TSA was performed, and 6 studies with a total of 680 patients were found. Data on change in hemoglobin, drain output, total blood loss, and transfusion were extracted. Meta-analysis was performed with stratification into reverse and anatomic TSA subgroups.

Results

TXA administration was associated with decreased change in hemoglobin (−0.63 g/dL; 95% CI, −0.87 to −0.39 g/dL; P < .00001), drain output (−112.05 mL; 95% CI, −182.29 to −41.81 mL; P < .0001), and total blood loss (−231.87 mL; 95% CI, −334.23 to −129.48 mL; P < .00001) after reverse TSA. There was a trend toward reduction in transfusion rate after reverse TSA (−4%; 95% CI, −8% to 0%; P = .06). TXA administration was associated with reduced drain output after anatomic TSA (−123.07 mL; 95% CI, −163.93 to −82.20 mL; P < 0.00001). TXA administration was not associated with decreased transfusion rate after anatomic TSA. Data to evaluate the effect of TXA on change in hemoglobin and total blood loss after anatomic TSA were insufficient.

Conclusions

Routine administration of TXA reduces perioperative blood loss and may reduce the risk of transfusion after reverse TSA. Future studies are needed to further characterize its effect on the risk of transfusion after reverse TSA and efficacy in anatomic TSA.

Total Hip Arthroplasty in the Outpatient Setting: What You Need to Know (Part 1)

The method by which surgeons conduct outpatient total hip arthroplasty (THA) procedures has yet to be fully standardized. Careful examination of components involved in the preoperative phase of outpatient hip arthroplasty procedures may lead to improved outcomes. This article will discuss methods for implementing successful outpatient THA protocols. Specifically it reviews information regarding patient selection criteria, preoperative education, and preoperative medical optimization.

Efficacy and Safety of Tranexamic Acid in Orthopaedic Fracture Surgery: A Meta-Analysis and Systematic Literature Review

BACKGROUND

Tranexamic acid (TXA) is an antifibrinolytic drug that has been shown to be effective in reducing blood loss and the need for transfusions after several orthopaedic surgeries. However, the effectiveness of TXA use in orthopaedic fracture surgeries still remains unclear. The purpose of this meta-analysis was to review existing literature with interest in the effectiveness and safety of TXA treatment in reducing total blood loss and transfusion rates for patients who underwent surgery for fracture repairs.

METHODS

An electronic literature search of PubMed, Embase, OVID, and the Cochrane Library was conducted to identify studies published before December 2016. All randomized controlled trials and cohort studies evaluating the efficacy of TXA during fracture repair surgeries were identified. Primary outcome measures included the number of patients receiving a blood transfusion and perioperative total blood loss. Data were analyzed using Comprehensive Meta-Analysis (CMA) statistical software.

RESULTS

Seven studies encompassing 559 patients met the inclusion criteria for the meta-analysis. Our meta-analysis indicated that when compared with the placebo control group, the use of TXA in fracture surgeries significantly reduced total blood loss by approximately 330 mL (P = 0.009), reduced the transfusion rate with a relative risk of 0.54 (P < 0.001), and decreased the drop of hemoglobin by 0.76 g/dL (P < 0.001). There was no significant difference between the number of thromboembolic events among the study groups (P = 0.24).

CONCLUSIONS

This study demonstrated that tranexamic acid may be used in orthopaedic fracture surgeries to reduce total blood loss, transfusion rates, and the drop in hemoglobin level, without increasing risk of venous thrombo-embolism. A limitation to these findings is the small number of studies available. Further studies need to be conducted to confirm these findings.

LEVEL OF EVIDENCE

Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Dose optimisation of intravenous tranexamic acid for elective hip and knee arthroplasty: The effectiveness of a single pre-operative dose

Objectives

We have increased the dose of tranexamic acid (TXA) in our enhanced total joint recovery protocol at our institution from 15 mg/kg to 30 mg/kg (maximum 2.5 g) as a single, intravenous (IV) dose. We report the clinical effect of this dosage change.

Methods

We retrospectively compared two cohorts of consecutive patients undergoing total hip arthroplasty (THA) or total knee arthroplasty (TKA) surgery in our unit between 2008 and 2013. One group received IV TXA 15 mg/kg, maximum 1.2 g, and the other 30 mg/kg, maximum 2.5 g as a single pre-operative dose. The primary outcome for this study was the requirement for blood transfusion within 30 days of surgery. Secondary measures included length of hospital stay, critical care requirements, re-admission rate, medical complications and mortality rates.

Results

A total of 1914 THA and 2537 TKA procedures were evaluated. In THA, the higher dose of TXA was associated with a significant reduction in transfusion (p = 0.02, risk ratio (RR) 0.74, 95% confidence interval (CI) 0.58 to 0.96) and rate of re-admission (p < 0.001, RR 0.50, 95% CI 0.35 to 0.71). There were reductions in the requirement for critical care (p = 0.06, RR 0.55, 95% CI 0.31 to 1.00), and in the length of stay from 4.7 to 4.3 days (p = 0.02). In TKA, transfusion requirements (p = 0.049, RR 0.64, 95% CI 0.41 to 0.99), re-admission rate (p = 0.001, RR 0.56, 95% CI 0.39 to 0.80) and critical care requirements (p < 0.003, RR 0.34, 95% CI 0.16 to 0.72) were reduced with the higher dose. Mean length of stay reduced from 4.6 days to 3.6 days (p < 0.01). There was no difference in the incidence of deep vein thrombosis, pulmonary embolism, gastrointestinal bleed, myocardial infarction, stroke or death in THA and TKA between cohorts.

Conclusion

We suggest that a single pre-operative dose of TXA, 30 mg/kg, maximum 2.5g, results in a lower transfusion requirement compared with a lower dose in patients undergoing elective primary hip and knee arthroplasty. However, these findings should be interpreted in the context of the retrospective non-randomised study design.

Cite this article: R. J. M. Morrison, B. Tsang, W. Fishley, I. Harper, J. C. Joseph, M. R. Reed. Dose optimisation of intravenous tranexamic acid for elective hip and knee arthroplasty: The effectiveness of a single pre-operative dose. Bone Joint Res 2017;6:499–505. DOI: 10.1302/2046-3758.68.BJR-2017-0005.R1.

Intravenous tranexamic acid reduces total blood loss in reverse total shoulder arthroplasty: a prospective, double-blinded, randomized, controlled trial

BACKGROUND

Patients undergoing reverse total shoulder arthroplasty (RTSA) are at risk of significant perioperative blood loss. To date, few studies have examined the effectiveness of tranexamic acid (TXA) to reduce blood loss in the setting of RTSA.

METHODS

In a prospective, double-blinded, single-surgeon trial, we analyzed 102 patients undergoing primary RTSA who were randomized to receive intravenous TXA (n = 53) or placebo (n = 49). Calculated total blood loss, drain output, and hemoglobin (Hb) drop were measured. Postoperative transfusions were recorded. Complications were assessed out to 6 weeks postoperatively.

RESULTS

Total blood loss was less for the TXA group (1122.4  ± 411.6 mL) than the placebo group (1472.6 ± 475.4 mL, P < .001). Total drain output was less for the TXA group (221.4 ± 126.2 mL) than the placebo group (371.9 ± 166.3 mL , P < .001). Total Hb loss was less in the TXA group (154.57 ± 60.29 g) compared with the placebo group (200.1 ± 65.5 g, P = .001). Transfusion rates differed significantly at postoperative day 1; however, overall transfusion rates did not vary significantly. Seven patients (14.3%) and 12 units were transfused in the placebo group compared with 3 patients (5.7%) and 3 units in the TXA group.

DISCUSSION

In this cohort of patients undergoing primary RTSA, TXA was effective in reducing total drain output, total Hb loss, and total blood loss compared with a placebo control.

A nested mechanistic sub-study into the effect of tranexamic acid versus placebo on intracranial haemorrhage and cerebral ischaemia in isolated traumatic brain injury: study protocol for a randomised controlled trial (CRASH-3 Trial Intracranial Bleeding Mechanistic Sub-Study [CRASH-3 IBMS])

Background

Tranexamic acid prevents blood clots from breaking down and reduces bleeding. However, it is uncertain whether tranexamic acid is effective in traumatic brain injury. The CRASH-3 trial is a randomised controlled trial that will examine the effect of tranexamic acid (versus placebo) on death and disability in 13,000 patients with traumatic brain injury. The CRASH-3 trial hypothesizes that tranexamic acid will reduce intracranial haemorrhage, which will reduce the risk of death. Although it is possible that tranexamic acid will reduce intracranial bleeding, there is also a potential for harm. In particular, tranexamic acid may increase the risk of cerebral thrombosis and ischaemia. The protocol detailed here is for a mechanistic sub-study nested within the CRASH-3 trial. This mechanistic sub-study aims to examine the effect of tranexamic acid (versus placebo) on intracranial bleeding and cerebral ischaemia.

Methods

The CRASH-3 Intracranial Bleeding Mechanistic Sub-Study (CRASH-3 IBMS) is nested within a prospective, double-blind, multi-centre, parallel-arm randomised trial called the CRASH-3 trial. The CRASH-3 IBMS will be conducted in a cohort of approximately 1000 isolated traumatic brain injury patients enrolled in the CRASH-3 trial. In the CRASH-3 IBMS, brain scans acquired before and after randomisation are examined, using validated methods, for evidence of intracranial bleeding and cerebral ischaemia. The primary outcome is the total volume of intracranial bleeding measured on computed tomography after randomisation, adjusting for baseline bleeding volume. Secondary outcomes include progression of intracranial haemorrhage (from pre- to post-randomisation scans), new intracranial haemorrhage (seen on post- but not pre-randomisation scans), intracranial haemorrhage following neurosurgery, and new focal ischaemic lesions (seen on post-but not pre-randomisation scans). A linear regression model will examine whether receipt of the trial treatment can predict haemorrhage volume. Bleeding volumes and new ischaemic lesions will be compared across treatment groups using relative risks and 95% confidence intervals.

Discussion

The CRASH-3 IBMS will provide an insight into the mechanism of action of tranexamic acid in traumatic brain injury, as well as information about the risks and benefits. Evidence from this trial could inform the management of patients with traumatic brain injury.

Trial registration

The CRASH-3 trial was prospectively registered and the CRASH-3 IBMS is an addition to the original protocol registered at the International Standard Randomised Controlled Trials registry (ISRCTN15088122) 19 July 2011, and ClinicalTrials.gov on 25 July 2011 (NCT01402882).

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-017-2073-6) contains supplementary material, which is available to authorized users.

Compliance of tranexamic acid administration to trauma patients at a level-one trauma centre

Introduction Current practice for the treatment of traumatic hemorrhage includes fluid resuscitation and the administration of blood products. The administration of tranexamic acid (TXA) within 8 hours of injury has been shown to significantly reduce mortality in a large, prospective, randomized controlled trial. As a result, TXA is widely used in trauma centres to manage trauma patients with major bleeding. The primary aim of this study was to assess the compliance of TXA administration at a level-one trauma centre in Hamilton, Ontario, Canada.

METHODS

We conducted a retrospective medical record review of consecutive adult trauma patients received at the Hamilton General Hospital between January 1, 2012 and December 31, 2014. Compliance with TXA administration was based on the inclusion criteria of the CRASH-2 trial.

RESULTS

Five hundred and thirty-four of 2,475 trauma patients met the inclusion criteria for TXA administration. Twenty-one patients who received TXA at peripheral hospital prior to their arrival at the level-one trauma centre were excluded from the analysis, and 18 patients were excluded due to missing data. One hundred and thirty-four patients received TXA, representing a compliance rate of 27%. Mean time from arrival to TXA administration was 47 minutes. Compliance increased for those who required massive transfusion and as the number of criteria for TXA administration increased.

CONCLUSIONS

Compliance with TXA administration to trauma patients with suspected major bleeding was low. Quality improvement strategies aimed at increasing appropriate use of TXA are warranted.

Effect of early tranexamic acid administration on mortality, hysterectomy, and other morbidities in women with post-partum haemorrhage (WOMAN): an international, randomised, double-blind, placebo-controlled trial

BACKGROUND

Post-partum haemorrhage is the leading cause of maternal death worldwide. Early administration of tranexamic acid reduces deaths due to bleeding in trauma patients. We aimed to assess the effects of early administration of tranexamic acid on death, hysterectomy, and other relevant outcomes in women with post-partum haemorrhage.

METHODS

In this randomised, double-blind, placebo-controlled trial, we recruited women aged 16 years and older with a clinical diagnosis of post-partum haemorrhage after a vaginal birth or caesarean section from 193 hospitals in 21 countries. We randomly assigned women to receive either 1 g intravenous tranexamic acid or matching placebo in addition to usual care. If bleeding continued after 30 min, or stopped and restarted within 24 h of the first dose, a second dose of 1 g of tranexamic acid or placebo could be given. Patients were assigned by selection of a numbered treatment pack from a box containing eight numbered packs that were identical apart from the pack number. Participants, care givers, and those assessing outcomes were masked to allocation. We originally planned to enrol 15 000 women with a composite primary endpoint of death from all-causes or hysterectomy within 42 days of giving birth. However, during the trial it became apparent that the decision to conduct a hysterectomy was often made at the same time as randomisation. Although tranexamic acid could influence the risk of death in these cases, it could not affect the risk of hysterectomy. We therefore increased the sample size from 15 000 to 20 000 women in order to estimate the effect of tranexamic acid on the risk of death from post-partum haemorrhage. All analyses were done on an intention-to-treat basis. This trial is registered with ISRCTN76912190 (Dec 8, 2008); ClinicalTrials.gov, number NCT00872469; and PACTR201007000192283.

FINDINGS

Between March, 2010, and April, 2016, 20 060 women were enrolled and randomly assigned to receive tranexamic acid (n=10 051) or placebo (n=10 009), of whom 10 036 and 9985, respectively, were included in the analysis. Death due to bleeding was significantly reduced in women given tranexamic acid (155 [1·5%] of 10 036 patients vs 191 [1·9%] of 9985 in the placebo group, risk ratio [RR] 0·81, 95% CI 0·65-1·00; p=0·045), especially in women given treatment within 3 h of giving birth (89 [1·2%] in the tranexamic acid group vs 127 [1·7%] in the placebo group, RR 0·69, 95% CI 0·52-0·91; p=0·008). All other causes of death did not differ significantly by group. Hysterectomy was not reduced with tranexamic acid (358 [3·6%] patients in the tranexamic acid group vs 351 [3·5%] in the placebo group, RR 1·02, 95% CI 0·88-1·07; p=0·84). The composite primary endpoint of death from all causes or hysterectomy was not reduced with tranexamic acid (534 [5·3%] deaths or hysterectomies in the tranexamic acid group vs 546 [5·5%] in the placebo group, RR 0·97, 95% CI 0·87-1·09; p=0·65). Adverse events (including thromboembolic events) did not differ significantly in the tranexamic acid versus placebo group.

INTERPRETATION

Tranexamic acid reduces death due to bleeding in women with post-partum haemorrhage with no adverse effects. When used as a treatment for postpartum haemorrhage, tranexamic acid should be given as soon as possible after bleeding onset.

FUNDING

London School of Hygiene & Tropical Medicine, Pfizer, UK Department of Health, Wellcome Trust, and Bill & Melinda Gates Foundation.

"Simplified International Recommendations for the Implementation of Patient Blood Management" (SIR4PBM)

BACKGROUND

More than 30% of the world's population are anemic with serious medical and economic consequences. Red blood cell transfusion is the mainstay to correct anemia, but it is also one of the top five overused procedures and carries its own risk and cost burden. Patient blood management (PBM) is a patient-centered and multidisciplinary approach to manage anemia, minimize iatrogenic blood loss, and harness tolerance to anemia in an effort to improve patient outcome. Despite resolution 63.12 of the World Health Organization in 2010 endorsing PBM and current guidelines which include evidence-based recommendations on the use of diagnostic/therapeutic resources to provide better health care, many hospitals have yet to implement PBM in routine clinical practice.

METHOD AND RESULTS

A number of experienced clinicians developed the following "Simplified International Recommendations for Patient Blood Management." We propose a series of simple, cost-effective, best-practice, feasible, and evidence-based measures that will enable any hospital to reduce both anemia prevalence on the day of intervention/surgery and anemia-related unnecessary transfusion in surgical and medical patients, including obstetrics and gynecology.

Mild volume acute normovolemic hemodilution is associated with lower intraoperative transfusion and postoperative pulmonary infection in patients undergoing cardiac surgery -- a retrospective, propensity matching study

Background

Perioperative allogenic transfusion is required in almost 50% of patients undergoing cardiac surgery and is associated with higher risk of mortality and morbidity (Xue et al., Lancet 387:1905, 2016; Ferraris et al., Ann Thorac Surg 91:944–82, 2011). Acute normovolemic hemodilution (ANH) is recommended as a potential strategy during cardiac surgery, but the blood conservation effect and the degree of ANH was still controversial. There is also an increasing concern about the improved outcomes associated with ANH. Therefore, a better understanding of the effect of mild volume ANH during cardiac surgery is urgently needed.

Methods

This retrospective study included 2058 patients who underwent cardiac surgery between 2010 and 2015. The study population was split into two groups (with and without mild volume ANH). Propensity score adjustment analysis was applied. We reported the association between the use of mild volume ANH and perioperative outcomes.

Results

A total of 1289 patients were identified. ANH was performed in 358 patients, and the remaining 931 patients did not receive any ANH. Five hundred of the total patients (38.8%) received perioperative RBC transfusions, 10% (129/1289) of patients received platelet, and 56.4% (727/1289) of patients received fresh frozen plasma transfusions. Mild volume ANH administration was significantly associated with decreased intraoperative RBC transfuse rate (8.5% vs. 14.4%; p = 0.013), number of RBC units (p = 0.019), and decreased postoperative pulmonary infection (6.8 vs. 11.3%; p = 0.036) during cardiac surgery. However, there was no significant difference regarding intraoperative fresh frozen plasma (FFP) and platelet concentrate transfusions, as well as postoperative and total perioperative allogeneic transfusions. Furthermore, there was no significant difference regarding postoperative outcomes including mortality, prolonged wound healing, stroke, atrial fibrillation, reoperation for postoperative bleeding and acute kidney injury. There was also no difference in postoperative ventilation time, length of ICU and hospital stay.

Conclusion

Based on the 5-year experience of mild volume ANH in cardiac surgeries with CPB in our large retrospective cohort, mild volume ANH was associated with decreased intraoperative RBC transfusion and postoperative pulmonary infection in Chinese patients undergoing cardiac surgery. However, there was no significant difference regarding postoperative and total perioperative allogeneic transfusions.

Electronic supplementary material

The online version of this article (doi:10.1186/s12871-017-0305-7) contains supplementary material, which is available to authorized users.

Effect of tranexamic acid on coagulation and fibrinolysis in women with postpartum haemorrhage (WOMAN-ETAC): protocol and statistical analysis plan for a randomized controlled trial

Background: Postpartum haemorrhage (PPH) is a leading cause of maternal death. Tranexamic acid has the potential to reduce bleeding and a large randomized controlled trial of its effect on maternal health outcomes in women with PPH (The WOMAN trial) is ongoing. We will examine the effect of tranexamic acid on fibrinolysis and coagulation in a subset of WOMAN trial participants.

Methods: Adult women with clinically diagnosed primary PPH after vaginal or caesarean delivery are eligible for inclusion in the WOMAN trial. In a sub-group of trial participants, blood samples will be collected at baseline and 30 minutes after the first dose of tranexamic acid or matching placebo.  Our primary objective is to evaluate the effect of tranexamic acid on fibrinolysis. Fibrinolysis will be assessed by measuring D-dimers and by rotational thromboelastometry (ROTEM). Secondary outcomes are international normalized ratio (INR), prothrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen, haemoglobin and platelets. We aim to include about 180 women from the University College Hospital, Ibadan in Nigeria.

Discussion:  This sub-study of WOMAN trial participants should provide information on the mechanism of action of tranexamic acid in women with postpartum haemorrhage. We present the trial protocol and statistical analysis plan. The trial protocol was registered prior to the start of patient recruitment. The statistical analysis plan was completed before un-blinding.

Trial registration: The trial was registered: ClinicalTrials.gov, Identifier NCT00872469 https://clinicaltrials.gov/ct2/show/NCT00872469; ISRCTN registry, Identifier ISRCTN76912190 http://www.isrctn.com/ISRCTN76912190 (Registration date: 22/03/2012).

Spine tumor resection among patients who refuse blood product transfusion: a retrospective case series

STUDY OBJECTIVE

To describe the perioperative blood conservation strategies and postoperative outcomes in patients who undergo complex spinal surgery for tumor resection and who also refuse blood product transfusion.

DESIGN

A retrospective case series.

SETTING

A single-center, tertiary care and academic teaching hospital in Canada.

PATIENTS

All adult patients undergoing elective major spine tumor resection and refusing blood product transfusion who were referred to our institutional Blood Utilization Program between June 1, 2004, and May 9, 2014.

MEASUREMENTS

Data on the use of iron, erythropoietin, preoperative autologous blood donation, acute normovolemic hemodilution, antifibrinolytic therapy, cell salvage, intraoperative hypotension, and active warming techniques were collected. Data on perioperative hemoglobin nadir, adverse outcomes, and hospital length of stay were also collected.

MAIN RESULTS

Four patients who refused blood transfusion (self-identified as Jehovah's Witnesses) underwent non-emergent complex spine surgery for recurrent chondrosarcoma, meningioma, metastatic adenocarcinoma, and metastatic malignant melanoma. All patients received 1 or more perioperative blood conservation strategy including preoperative iron and/or erythropoietin, intraoperative antifibrinolytic therapy, and cell salvage. No patients experienced severe perioperative anemia (average hemoglobin nadir, 124 g/L) or anemia-related postoperative complications.

CONCLUSIONS

Patients who decline blood product transfusion can successfully undergo major spine tumor resection. Careful patient selection and timely referral for perioperative optimization such that the risk of severe anemia is minimized are important for success.

Topical versus systemic tranexamic acid after total knee and hip arthroplasty: A meta-analysis of randomized controlled trials

BACKGROUND

Tranexamic acid (TXA) is an antifibrinolytic drug widely used to reduce blood loss during joint replacements, including total knee arthroplasty (TKA) and total hip arthroplasty (THA). However, there is no final consensus regarding the composition of an optimal administration of TXA regime between topical and systemic (intravenous). The purpose of our study was to compare the efficacy of topical and intravenous (IV) regimen of TXA during TKA and THA.

METHODS

Five relevant electronic online databases, PubMed, EMBASE, the Cochrane Central Register of Controlled Trials, Web of Science and Chinese Biomedical Database were systematically searched in November 2015. Randomized controlled trials (RCTs) that compared topical with intravenous TXA in patients with TKA or THA were included. The search terms included "topical," "intravenous," "tranexamic acid," "knee arthroplasty" and "hip arthroplasty." Two reviewers independently extracted data and assessed the risk of bias and study quality. Data were analyzed with Review Manager 5.3 software. Grades of Recommendation Assessment, Development and Evaluation (GRADE) were used to assess the quality of evidence.

RESULTS

Sixteen RCTs with 1250 patients undergoing TKA and 4 RCTs involving 550 patients undergoing THA were included. There were no significant differences in total blood loss (mean difference [MD]TKA = -28.72 mL, 95% confidence interval [CI] -195.97 to 138.54 mL, P = 0.74; MDTHA = 14.03 mL, 95% CI -35.53 to 63.59 mL; P = 0.78), total drain out (MDTKA = -3.09 mL, 95% CI -39.05 to 32.88 mL; P = 0.87; MDTHA -31.00 mL, 95% CI -66.56 to 4.66 mL; P = 0.09), and transfusion rates (ORTKA = 0.90, 95% CI 0.58-1.40, P = 0.64; ORTHA = 1.19, 95% CI 0.67-2.09; P = 0.63) between topical and intravenous (IV) TXA.

CONCLUSIONS

The current evidence suggested that topical TXA was equally effective and safe compared with intravenous TXA in reducing blood loss and transfusion rate following TKA or THA. We recommended that either topically or systemically could be used in TKA and THA to decrease perioperative blood loss.

Anti-hemorrhagic effect of prophylactic tranexamic acid in benign hysterectomy-a double-blinded randomized placebo-controlled trial

BACKGROUND

Hysterectomy is one of the most frequently performed major gynecological surgical procedures. Even when the indication for the procedure is benign, relatively high complication rates have been reported. Perioperative bleeding seems to represent the most common cause of complications and in 2004, 8% of all women in Denmark undergoing benign hysterectomy experienced a bleeding complication. Tranexamic acid is an antifibrinolytic agent that has shown to effectively reduce bleeding complications within other surgical and medical areas. However, knowledge about the drug's effect in relation to benign hysterectomy is still missing.

OBJECTIVE

To investigate the antihemorrhagic effect of prophylactic tranexamic acid in elective benign hysterectomy.

STUDY DESIGN

A double-blinded randomized placebo-controlled trial was conducted at 4 gynecological departments in Denmark from April 2013 to October 2014. A total of 332 women undergoing benign abdominal, laparoscopic, or vaginal hysterectomy were included in the trial, randomized to either 1 g of intravenous tranexamic acid or placebo at start of surgery. Chi-square test and Student t test statistical analyses were applied.

RESULTS

The primary outcome of intraoperative total blood loss was reduced in the group treated with tranexamic acid compared to the placebo group when estimated both subjectively by the surgeon and objectively by weight (98.4 mL vs 134.8 mL, P = .006 and 100.0 mL vs 166.0 mL, P = .004). The incidence of blood loss ≥500 mL was also significantly reduced (6 vs 21, P = .003), as well as the use of open-label tranexamic acid (7 vs 18, P = .024). Furthermore, the risk of reoperations owing to postoperative hemorrhage was significantly reduced in the tranexamic acid group compared to the placebo group (2 vs 9, P = .034). This corresponds to an absolute risk reduction of 4.2% and number needed to treat of 24. No incidence of thromboembolic events or death was observed in any of the groups.

CONCLUSION

The results support the hypothesis that prophylactic treatment with tranexamic acid reduces the overall total blood loss, the incidence of substantial blood loss, and the need for reoperations owing to postoperative hemorrhage in relation to benign hysterectomy. No incidences of serious adverse events occurred. Thus, tranexamic acid should be considered as a prophylactic treatment prior to elective benign hysterectomy.

Combined Intra-Articular and Intravenous Tranexamic Acid Reduces Blood Loss in Total Knee Arthroplasty: A Randomized, Double-Blind, Placebo-Controlled Trial

BACKGROUND

In total knee arthroplasty, both intravenous (IV) and intra-articular (IA) administration of tranexamic acid (TXA) have been shown to reduce blood loss in several randomized controlled trials, although routine use of systemic TXA is considerably more common. However, to our knowledge, the additional benefit of IA administration of TXA when combined with IV administration, without the use of a tourniquet, has not been previously investigated. Thus, the aim of this study was to evaluate whether combined IV and IA administration of TXA reduced total blood loss compared with IV-only administration of TXA.

METHODS

In this randomized, double-blind, placebo-controlled trial, 60 patients scheduled for total knee arthroplasty were randomized to one of two interventions. The TXA IV and IA group received combined administration of TXA consisting of 1 g administered intravenously preoperatively and 3 g diluted in 100 mL of saline solution administered intra-articularly after closure of the capsule. The TXA IV and placebo group received 1 g of TXA administered intravenously only and 100 mL of saline solution administered intra-articularly. IA TXA was administrated through a needle. The primary outcome was the 24-hour calculated blood loss. Secondary outcomes were blood loss on postoperative day 2, thromboembolic complications, and transfusion rate. Blood loss was calculated by hemoglobin differences using the Gross formula.

RESULTS

Data on the primary outcome were available for all 60 included patients. Baseline characteristics were comparable between the allocation groups. The mean 24-hour blood loss (and standard deviation) was 466 ± 313 mL in the TXA IV and IA group compared with 743 ± 358 mL in the TXA IV and placebo group; treatment effect (difference), 277 mL (95% confidence interval [CI], 103 to 451 mL) (p = 0.002). Second-day blood loss was 644 ± 382 mL in the TXA IV and IA group compared with 1017 ± 519 mL in the TXA IV and placebo group; treatment effect, 373 mL (95% CI, 132 to 614 mL) (p = 0.003). No thromboembolic complications were observed within 90 days postoperatively.

CONCLUSIONS

The combined administration of IV and IA TXA resulted in a clinically relevant reduction in blood loss of 37% compared with IV TXA alone both at 24 hours postoperatively and on postoperative day 2. No thromboembolic complications were observed.

LEVEL OF EVIDENCE

Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

The effect of tranexamic acid on the risk of death and hysterectomy in women with post-partum haemorrhage: statistical analysis plan for the WOMAN trial

BACKGROUND

Severe haemorrhage is a leading cause of maternal death worldwide. Most haemorrhage deaths occur soon after childbirth. Severe post-partum bleeding is sometimes managed by the surgical removal of the uterus (hysterectomy). Death and hysterectomy are important health consequences of post-partum haemorrhage, and clinical trials of interventions aimed at preventing these outcomes are needed.

METHODS

The World Maternal Antifibrinolytic trial aims to determine the effect of tranexamic acid on death, hysterectomy and other health outcomes in women with post-partum haemorrhage. It is an international, multicentre, randomised trial. Approximately 20,000 women with post-partum haemorrhage will be randomly allocated to receive an intravenous injection of either tranexamic acid or matching placebo in addition to usual care. The primary outcome measure is a composite of death in hospital or hysterectomy within 42 days of delivery. The cause of death will be described. Secondary outcomes include death, death due to bleeding, hysterectomy, thromboembolic events, blood transfusion, surgical and radiological interventions, complications, adverse events and quality of life. The health status and occurrence of thromboembolic events in breastfed babies will also be reported. We will conduct subgroup analyses for the primary outcome by time to treatment, type of delivery and cause of haemorrhage. We will conduct an analysis of treatment effect adjusted for baseline risk.

DISCUSSION

The World Maternal Antifibrinolytic trial should provide reliable evidence for the efficacy of tranexamic acid in the prevention of death, hysterectomy and other outcomes that are important to patients. We present a protocol update and the statistical analysis plan for the trial.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN76912190 (Registration date 08 December 2008), Clinicaltrials.gov NCT00872469 (Registration date 30 March 2009) and Pan African Clinical Trials Registry: PACTR201007000192283 (Registration date 02 September 2010).

Prehospital administration of tranexamic acid in trauma patients

Background

Evidence on prehospital administration of the antifibrinolytic tranexamic acid (TXA) in civilian trauma populations is scarce. The aim was to study whether prehospital TXA use in trauma patients was associated with improved outcomes.

Methods

The prehospital database of the ADAC (General German Automobile Club) Air Rescue Service was linked with the TraumaRegister of the German Trauma Society to reidentify patients documented in both registries. Primarily admitted trauma patients (2012 until 2014) who were treated with TXA during the prehospital phase were matched with patients who had not received prehospital TXA, applying propensity score-based matching.

Results

The matching yielded two identical cohorts (n = 258 in each group), since there were no significant differences in demographics or injury characteristics (mean Injury Severity Score 24 ± 14 [TXA] vs. 24 ± 16 [control]; p = 0.46). The majority had sustained blunt injury (90.3 % vs. 93.0 %; p = 0.34). There were no differences with respect to prehospital therapy, including rates of intubation, chest tube insertion or both administration of i.v. fluids and catecholamines. During ER treatment, the TXA cohort received fewer numbers of red blood cells and plasma units, but without reaching statistical significance. Incidences of organ failure, sepsis or thromboembolism showed no significant differences as well, although data were incomplete for these parameters. Early mortality was significantly lower in the TXA group (e.g., 24-h mortality 5.8 % [TXA] vs. 12.4 % [control]; p = 0.01), and mean time to death was 8.8 ± 13.4 days vs. 3.6 ± 4.9 days, respectively (p = 0.001). Overall hospital mortality was similar in both groups (14.7 % vs. 16.3 %; p = 0.72). The most pronounced mortality difference was observed in patients with a high propensity score, reflecting severe injury load.

Conclusions

This is the first civilian study, to our knowledge, in which the effect of prehospital TXA use in trauma patients has been examined. TXA was associated with prolonged time to death and significantly improved early survival. Until further evidence emerges, the results of this study support the use of TXA during prehospital treatment of severely injured patients.

Systemic and Topical Use of Tranexamic Acid in Spinal Surgery: A Systematic Review

Study Design Combination of narrative and systematic literature reviews. Objectives Massive perioperative blood loss in complex spinal surgery often requires blood transfusions and can negatively affect patient outcome. Systemic use of the antifibrinolytic agent tranexamic acid (TXA) has become widely used in the management of surgical bleeding. We review the clinical evidence for the use of intravenous TXA as a hemostatic agent in spinal surgery and discuss the emerging role for its complementary use as a topical agent to reduce perioperative blood loss from the surgical site. Through a systematic review of published and ongoing investigations on topical TXA for spinal surgery, we wish to make spine practitioners aware of this option and to suggest opportunities for further investigation in the field. Methods A narrative review of systemic TXA in spinal surgery and topical TXA in surgery was conducted. Furthermore, a systematic search (using PRISMA guidelines) of PubMed (MEDLINE), EMBASE, and Cochrane CENTRAL databases as well as World Health Organization International Clinical Trials Registry Platform, ClinicalTrials.gov (National Institutes of Health), and International Standard Randomized Controlled Trial Number registries was conducted to identify both published literature and ongoing clinical trials on topical TXA in spinal surgery. Results Of 1,631 preliminary search results, 2 published studies were included in the systematic review. Out of 285 ongoing clinical trials matching the search criteria, a total of 4 relevant studies were included and reviewed. Conclusion Intravenous TXA is established as an efficacious hemostatic agent in spinal surgery. Use of topical TXA in surgery suggests similar hemostatic efficacy and potentially improved safety as compared with intravenous TXA. For spinal surgery, the literature on topical TXA is sparse but promising, warranting further clinical investigation and consideration as a clinical option in cases with significant anticipated surgical site blood loss.

Care bundles for management of obstetrical hemorrhage

Peripartum hemorrhage is one of the most preventable causes of maternal mortality worldwide. Much effort has been directed toward creating programs that address deficits in maternity care responsible for preventable hemorrhage-related morbidity and mortality. To have a significant impact on outcomes, such programs must address both providers and processes involved in the delivery of maternity care. At the core of a successful program, are standardized care bundles integrating medical and surgical techniques for managing hemorrhage with principles of transfusion medicine and critical care. In this article, we review the components of the safety bundle for obstetric hemorrhage developed by ACOG District II Safe Motherhood Initiative.

Comprehensive review on endonasal endoscopic sinus surgery

Endonasal endoscopic sinus surgery is the standard procedure for surgery of most paranasal sinus diseases. Appropriate frame conditions provided, the respective procedures are safe and successful. These prerequisites encompass appropriate technical equipment, anatomical oriented surgical technique, proper patient selection, and individually adapted extent of surgery. The range of endonasal sinus operations has dramatically increased during the last 20 years and reaches from partial uncinectomy to pansinus surgery with extended surgery of the frontal (Draf type III), maxillary (grade 3-4, medial maxillectomy, prelacrimal approach) and sphenoid sinus. In addition there are operations outside and beyond the paranasal sinuses. The development of surgical technique is still constantly evolving. This article gives a comprehensive review on the most recent state of the art in endoscopic sinus surgery according to the literature with the following aspects: principles and fundamentals, surgical techniques, indications, outcome, postoperative care, nasal packing and stents, technical equipment.

Efficacy and Safety of Tranexamic Acid in Bilateral Total Knee Replacement: A Meta-Analysis and Systematic Review

Background

Tranexamic acid (TXA) has been well documented to reduce blood loss and transfusion requirements in patients undergoing unilateral total knee arthroplasty (TKA). However, the efficacy and safety of TXA in simultaneous bilateral TKA have not been clearly defined. The aim of our study was to systematically review the existing evidence regarding the role of TXA in patients undergoing simultaneous bilateral TKA.

Material/Methods

A systematic search of all studies published through June 2014 was performed using Medline, EMBASE, OVID, and other databases. All studies that compared the efficacy and safety of TXA administration in simultaneous bilateral TKA patients were identified. The data from the included trials were extracted and analyzed regarding blood loss and transfusion rates. The evidence quality levels of the selected articles were evaluated using a grading system.

Results

Six studies were included, in which a total of 245 patients received TXA and 271 patients were controls. Overall, the results demonstrated that the use of TXA significantly reduced total blood loss by a mean of 371.1 ml (95% confidence interval (CI)=−412.12 to −330.09; p<0.001) and reduced the number of patients requiring blood transfusion (risk ratio (RR)=0.16; 95% CI=0.10 to 0.28; p<0.001). No significant differences in adverse effects such as deep vein thrombosis (DVT) or pulmonary embolism (PE) were noted in any group.

Conclusions

The intravenous use of TXA in patients undergoing simultaneous bilateral TKA is effective and safe and results in significantly reduced estimated blood loss and transfusion rates. No significant difference was observed in the incidence of side effects. Due to the limitations in the evidence quality of current meta-analyses, well-conducted, larger, high-quality randomized controlled trials (RCTs) are required.

Randomized clinical trial of topical tranexamic acid after reduction mammoplasty

BACKGROUND

The antifibrinolytic drug tranexamic acid is currently being rediscovered for both trauma and major surgery. Intravenous administration reduces the need for blood transfusion and blood loss by about one-third, but routine administration in surgery is not yet advocated owing to concerns regarding thromboembolic events. The aim of this study was to investigate whether topical application of tranexamic acid to a wound surface reduces postoperative bleeding.

METHODS

This was a randomized double-blind placebo-controlled trial on 30 consecutive women undergoing bilateral reduction mammoplasty. On one side the wound surfaces were moistened with 25 mg/ml tranexamic acid before closure, and placebo (saline) was used on the other side. Drain fluid production was measured for 24 h after surgery, and pain was measured after 3 and 24 h. Postoperative complications including infection, seroma, rebleeding and suture reactions were recorded.

RESULTS

Topical application of tranexamic acid to the wound surface after reduction mammoplasty reduced drain fluid production by 39 per cent (median 12·5 (range 0-44) versus 20·5 (0-100) ml; P = 0·038). Adverse effects were not observed. There were no significant differences in postoperative pain scores or complications.

CONCLUSION

Topical application of dilute tranexamic acid reduced bleeding in this model. The study adds to the evidence that this simple procedure may reduce wound bleeding after surgery.

REGISTRATION NUMBER

NCT01964781 ( http://www.clinicaltrials.gov).

The efficacy of tranexamic acid in hip hemiarthroplasty surgery: an observational cohort study

Tranexamic acid (TXA) has been shown to reduce perioperative blood loss in elective lower limb arthroplasty surgery. There are potentially even greater physiological benefits in minimising blood loss in hip fracture surgery, however limited evidence exists for TXA use in hemiarthroplasty surgery. This study investigates the effect of TXA use on postoperative transfusion rates and haemoglobin (Hb) levels specifically following hemiarthroplasty surgery for hip fractures. A retrospective cohort study was conducted for consecutive hip hemiarthroplasties for fractures between June 2013 and October 2014 comparing patients with or without prophylactic TXA before incision. During the study, 305 hemiarthroplasties were performed with 271 cases eligible. TXA was given in 84 (31%) cases, and both patient groups were matched for known confounding factors. Patients given TXA had a lower transfusion rate (6% vs. 19%. p=0.005) and less blood loss (Hb drop>20g/L) on day 1 post surgery (26% vs. 42%; p=0.014). One transfusion was prevented with every 8 patients given prophylactic TXA. There were no differences in the 30 and 90-day mortality rates with TXA use. Tranexamic acid is safe, cost-effective and reduces the need for blood transfusion and should be considered in all patients undergoing hip hemiarthroplasty for fractures.

Patient blood management to reduce surgical risk

BACKGROUND

Preoperative anaemia and perioperative blood transfusion are both identifiable and preventable surgical risks. Patient blood management is a multimodal approach to address this issue. It focuses on three pillars of care: the detection and treatment of preoperative anaemia; the reduction of perioperative blood loss; and harnessing and optimizing the patient-specific physiological reserve of anaemia, including restrictive haemoglobin transfusion triggers. This article reviews why patient blood management is needed and strategies for its incorporation into surgical pathways.

METHODS

Studies investigating the three pillars of patient blood management were identified using PubMed, focusing on recent evidence-based guidance for perioperative management.

RESULTS

Anaemia is common in surgical practice. Both anaemia and blood transfusion are independently associated with adverse outcomes. Functional iron deficiency (iron restriction due to increased levels of hepcidin) is the most common cause of preoperative anaemia, and should be treated with intravenous iron. Intraoperative blood loss can be reduced with antifibrinolytic drugs such as tranexamic acid, and cell salvage should be used. A restrictive transfusion practice should be the standard of care after surgery.

CONCLUSION

The significance of preoperative anaemia appears underappreciated, and its detection should lead to routine investigation and treatment before elective surgery. The risks of unnecessary blood transfusion are increasingly being recognized. Strategic adoption of patient blood management in surgical practice is recommended, and will reduce costs and improve outcomes in surgery.

Forum for debate: Safety of allogeneic blood transfusion alternatives in the surgical/critically ill patient

In recent years, several safety alerts have questioned or restricted the use of some pharmacological alternatives to allogeneic blood transfusion in established indications. In contrast, there seems to be a promotion of other alternatives, based on blood products and/or antifibrinolytic drugs, which lack a solid scientific basis. The Multidisciplinary Autotransfusion Study Group and the Anemia Working Group España convened a multidisciplinary panel of 23 experts belonging to different healthcare areas in a forum for debate to: 1) analyze the different safety alerts referred to certain transfusion alternatives; 2) study the background leading to such alternatives, the evidence supporting them, and their consequences for everyday clinical practice, and 3) issue a weighted statement on the safety of each questioned transfusion alternative, according to its clinical use. The members of the forum maintained telematics contact for the exchange of information and the distribution of tasks, and a joint meeting was held where the conclusions on each of the items examined were presented and discussed. A first version of the document was drafted, and subjected to 4 rounds of review and updating until consensus was reached (unanimously in most cases). We present the final version of the document, approved by all panel members, and hope it will be useful for our colleagues.

Tranexamic acid in trauma: how should we use it?

Tranexamic acid (TXA) reduces blood loss by inhibiting the enzymatic breakdown of fibrin. It is often used in surgery to decrease bleeding and the need for blood transfusion. In 2011, results from a multi-center, randomized, and placebo-controlled trial (CRASH-2 trial) showed that TXA (1 g loading dose over 10 min followed by an infusion of 1 g over 8 h) safely reduces mortality in bleeding trauma patients. Initiation of TXA treatment within 3 h of injury reduces the risk of hemorrhage death by about one-third, regardless of baseline risk. Because it does not have any serious adverse effects, TXA can be administered to a wide spectrum of bleeding trauma patients. Limiting its use to the most severely injured or those with a diagnosis of 'hyperfibrinolysis' would result in thousands of avoidable deaths. A clinical trial (CRASH-3 trial) of TXA in patients with traumatic brain injury is now in progress.

Prevention of Bleeding in Orthognathic Surgery--A Systematic Review and Meta-Analysis of Randomized Controlled Trials

PURPOSE

The objective of the present study was to evaluate the efficacy of hemostatic adjuncts on intraoperative blood loss (IOB) in orthognathic surgery (OS) detected by randomized controlled trials (RCTs) of the highest quality.

MATERIALS AND METHODS

A search of the Medline, Cochrane, Embase, and Web of Science databases was performed in January 2015, and the risk of bias was assessed using the Jadad and Delphi scales. The predictor variable was the hemostatic measures, and the main outcome variable was the total IOB volume. The secondary outcome variables were the hemoglobin and hematocrit and operating time. This review is registered at PROSPERO (CRD42014014840).

RESULTS

Eleven trials were included for review. The individual trials demonstrated the effects on IOB from hypotensive anesthetic regimens, the use of aprotinin, and the herbal medicine Yunnan Baiyao. Six studies of tranexamic acid (TXA), with 288 patients, were suitable for a meta-analysis of continuous data. TXA reduced IOB by an average of 171 mL (95% confidence interval [CI] -230 to -112; P < .00001). Its topical use yielded similarly significant results (mean difference -197, 95% CI -319 to -76; P < .001). A subgroup analysis showed a decreased operating time in the TXA groups by an average of 15 minutes (mean difference -14.78, 95% CI -22.21 to -7.35; P < .0001).

CONCLUSIONS

Efficient hemostatic adjuncts exist for OS. Our meta-analysis showed that TXA significantly reduces IOB by an average of one third, regardless of whether it was given intravenously (IV) or applied topically. Additional RCTs are needed to confirm the effect of topical TXA in OS, and larger studies of intravenous administration are needed before any routine recommendations. No hemostatic effect of hypotensive anesthesia was found, mainly owing to imprecise descriptions of the blinding procedures. Transparent and uniform trial reporting is thus encouraged in future studies.

Efficacy of tranexamic acid on surgical bleeding in spine surgery: a meta-analysis

BACKGROUND CONTEXT

Spine surgery is usually associated with large amount of blood loss, necessitating blood transfusions. Blood loss-associated morbidity can be because of direct risks, such as hypotension and organ damage, or as a result of blood transfusions. The antifibrinolytic, tranexamic acid (TXA), is a lysine analog that inhibits activation of plasminogen and has shown to be beneficial in reducing surgical blood loss.

PURPOSE

To consolidate the findings of randomized controlled trials (RCTs) investigating the use of TXA on surgical bleeding in spine surgery.

STUDY DESIGN

A metaanalysis.

STUDY SAMPLE

Randomized controlled trials investigating the effectiveness of intravenous TXA in reducing blood loss in spine surgery, compared with a placebo/no treatment group.

METHODS

MEDLINE, Embase, Cochrane controlled trials register, and Google Scholar were used to identify RCTs published before January 2014 that examined the effectiveness of intravenous TXA on reduction of blood loss and blood transfusions, compared with a placebo/no treatment group in spine surgery. Metaanalysis was performed using RevMan 5. Weighted mean difference with 95% confidence intervals was used to summarize the findings across the trials for continuous outcomes. Dichotomous data were expressed as risk ratios with 95% confidence intervals. A p<.05 was considered statistically significant.

RESULTS

Eleven RCTs were included for TXA (644 total patients). Tranexamic acid reduced intraoperative, postoperative, and total blood loss by an average of 219 mL ([-322, -116], p<.05), 119 mL ([-141, -98], p<.05), and 202 mL ([-299, -105], p<.05), respectively. Tranexamic acid led to a reduction in proportion of patients who received a blood transfusion (risk ratio 0.67 [0.54, 0.83], p<.05) relative to placebo. There was one myocardial infarction (MI) in the TXA group and one deep vein thrombosis (DVT) in placebo.

CONCLUSIONS

Tranexamic acid reduces surgical bleeding and transfusion requirements in patients undergoing spine surgery. Tranexamic acid does not appear to be associated with an increased incidence of pulmonary embolism, DVT, or MI.

Modern Patient Blood Management in Arthroplasty

One of the oldest and still commonest procedures in clinical practice, allogeneic blood transfusion (ABT), is not fully supported by available evidence. In the last few decades, increasing concerns about unfavorable outcomes associated with ABT, anticipation of future insufficient blood supply, and awareness of the cost (direct and indirect) of transfusion have led to the promotion of patient blood management (PBM) as a cost-effective strategy, beneficial for patients as well as for society (Shander et al. 2010). PBM programs utilize a series of measures with a proven ability to reduce ABT and to be cost-effective. Despite that the impact of PBM on patient clinical outcomes needs to be fully defined and future studies are needed, PBM should be adopted as a new standard of care.

Mechanism of action of tranexamic acid in bleeding trauma patients: an exploratory analysis of data from the CRASH-2 trial

Introduction

To investigate the mechanism of action of tranexamic acid (TXA) in bleeding trauma patients, we examined the timing of its effect on mortality. We hypothesised that if TXA reduces mortality by decreasing blood loss, its effect should be greatest on the day of the injury when bleeding is most profuse. However, if TXA reduces mortality via an anti-inflammatory mechanism its effect should be greater over the subsequent days.

Methods

Exploratory analysis, including per-protocol analyses, of data from the CRASH-2 trial, a randomised placebo controlled trial of the effect of TXA on mortality in 20,211 trauma patients with, or at risk of, significant bleeding. We examined hazard ratios (HR) and 95% confidence intervals for all-cause mortality, deaths due to bleeding and non-bleeding deaths, according to the day since injury. The CRASH-2 trial is registered as ISRCTN86750102 and ClinicalTrials.gov NCT00375258.

Results

The effect of TXA on mortality is greatest for deaths occurring on the day of the injury (HR all-cause mortality = 0.83, 0.73 to 0.93). This survival benefit is only evident in patients in whom treatment is initiated within 3 hours of their injury (HR ≤3 hours = 0.78, 0.68 to 0.90; HR >3 hours = 1.02, 0.76 to 1.36). Initiation of TXA treatment within 3 hours of injury reduced the hazard of death due to bleeding on the day of the injury by 28% (HR = 0.72, 0.60 to 0.86). TXA treatment initiated beyond 3 hours of injury appeared to increase the hazard of death due to bleeding, although the estimates were imprecise.

Conclusions

Early administration of tranexamic acid appears to reduce mortality primarily by preventing exsanguination on the day of the injury.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-014-0685-8) contains supplementary material, which is available to authorized users.

[Efficacy and safety of tranexamic acid administration for the prevention and/or the treatment of post-partum haemorrhage: a systematic review with meta-analysis]

OBJECTIVE(S)

Assess the efficacy and safety of tranexamic acid administration for the prevention and/or the treatment of postpartum haemorrhage.

STUDY DESIGN

Systematic review with meta-analysis.

MATERIAL AND METHODS

Systematic review of the literature with the aim of identifying prospective, randomised, controlled trials that assessed the effect of tranexamic acid on peripartum blood loss and transfusion requirement in three clinical contexts: (i) prevention of post-partum haemorrhage in case of elective caesarean section, (ii) prevention of post-partum haemorrhage in case of vaginal delivery, (iii) treatment of post-partum haemorrhage.

RESULTS

Prophylactic administration of tranexamic acid reduced blood loss (mean difference for intraoperative blood loss: -177.9mL, IC 95%: -189.51 to -166.35, total blood loss: -183.94, IC 95%: -198.29 to -169.60), and the incidence of severe post-partum haemorrhage (OR: 0.49, IC 95%: 0.33 to 0.74). None of the published trials assessed the effect of tranexamic acid on blood products administration or transfusion requirement. Only one study assessed and reported the efficacy of tranexamic acid when administered as a treatment for postpartum haemorrhage. A significant reduction in blood loss was reported within 30 minutes after randomisation (P=0.03) and confirmed after 6 hours (median: 170mL (58-323) vs 221mL (110-543), P=0.04). None of the included studies adequately studied the incidence of side effects after tranexamic acid administration.

CONCLUSION

Although tranexamic acid administration seemed to significantly reduce blood loss and the incidence of severe post-partum haemorrhage, further prospective trials are needed to confirm the efficacy and safety of tranexamic administration in the treatment of postpartum haemorrhage. Those studies should assess the pharmacokinetic profile and the safety of this drug in pregnant women.

Applying results from clinical trials: tranexamic acid in trauma patients

This paper considers how results from clinical trials should be applied in the care of patients, using the results of the Clinical Randomisation of an Antifibrinolytic in Significant Haemorrhage (CRASH-2) trial of tranexamic acid in bleeding trauma patients as a case study. We explain why an understanding of the mechanisms of action of the trial treatment, and insight into the factors that might be relevant to this mechanism, is critical in order to properly apply (generalise) trial results and why it is not necessary that the trial population is representative of the population in which the medicine will be used. We explain why cause (mechanism)-specific mortality is more generalizable than all-cause mortality and why the risk ratio is the generalizable measure of the effect of the treatment. Overall, we argue that a biological insight into how the treatment works is more relevant when applying research results to patient care than the application of statistical reasoning.