Effect of tranexamic acid on surgical bleeding: systematic review and cumulative meta-analysis

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

BACKGROUND

Antifibrinolytics reduce death from bleeding in trauma and post-partum haemorrhage. We examined the effect of treatment delay on the effectiveness of antifibrinolytics.

METHODS

We did an individual patient-level data meta-analysis of randomised trials done with more than 1000 patients that assessed antifibrinolytics in acute severe bleeding. We identified trials done between Jan 1, 1946, and April 7, 2017, from MEDLINE, Embase, the Cochrane Central Register of Controlled Trials (CENTRAL), Web of Science, PubMed, Popline, and the WHO International Clinical Trials Registry Platform. The primary measure of treatment benefit was absence of death from bleeding. We examined the effect of treatment delay on treatment effectiveness using logistic regression models. We investigated the effect of measurement error (misclassification) in sensitivity analyses. This study is registered with PROSPERO, number 42016052155.

FINDINGS

We obtained data for 40 138 patients from two randomised trials of tranexamic acid in acute severe bleeding (traumatic and post-partum haemorrhage). Overall, there were 3558 deaths, of which 1408 (40%) were from bleeding. Most (884 [63%] of 1408) bleeding deaths occurred within 12 h of onset. Deaths from post-partum haemorrhage peaked 2-3 h after childbirth. Tranexamic acid significantly increased overall survival from bleeding (odds ratio [OR] 1·20, 95% CI 1·08-1·33; p=0·001), with no heterogeneity by site of bleeding (interaction p=0·7243). Treatment delay reduced the treatment benefit (p<0·0001). Immediate treatment improved survival by more than 70% (OR 1·72, 95% CI 1·42-2·10; p<0·0001). Thereafter, the survival benefit decreased by 10% for every 15 min of treatment delay until 3 h, after which there was no benefit. There was no increase in vascular occlusive events with tranexamic acid, with no heterogeneity by site of bleeding (p=0·5956). Treatment delay did not modify the effect of tranexamic acid on vascular occlusive events.

INTERPRETATION

Death from bleeding occurs soon after onset and even a short delay in treatment reduces the benefit of tranexamic acid administration. Patients must be treated immediately. Further research is needed to deepen our understanding of the mechanism of action of tranexamic acid.

FUNDING

UK NIHR Health Technology Assessment programme, Pfizer, BUPA Foundation, and J P Moulton Charitable Foundation (CRASH-2 trial). London School of Hygiene & Tropical Medicine, Pfizer, UK Department of Health, Wellcome Trust, and Bill & Melinda Gates Foundation (WOMAN trial).

Tranexamic Acid Use in Prehospital Uncontrolled Hemorrhage

The use of tranexamic acid (TXA) in the treatment of trauma patients was relatively unexplored until the landmark Clinical Randomisation of an Antifibrinolytic in Significant Haemorrhage-2 (CRASH-2) trial in 2010 demonstrated a reduction in mortality with the use of TXA. Although this trial was a randomized, double-blinded, placebo-controlled study incorporating >20,000 patients, numerous limitations and weaknesses have been described. As a result, additional studies have followed, delineating the potential risks and benefits of TXA administration. A systematic review of the literature to date reveals a mortality benefit of early (ideally <1 hour and no later than 3 hours after injury) TXA administration in the treatment of severely injured trauma patients (systolic blood pressure <90 mm Hg, heart rate >110). Combined with abundant literature showing a reduction in bleeding in elective surgery, the most significant benefit may be administration of TXA before the patient goes into shock. Those trials that failed to show a mortality benefit of TXA in the treatment of hemorrhagic shock acknowledged that most patients received blood products before TXA administration, thus confounding the results. Although the use of prehospital TXA in the severely injured trauma patient will become more clear with the trauma studies currently underway, the current literature supports the use of prehospital TXA in this high-risk population. We recommend considering a 1 g TXA bolus en route to definitive care in high-risk patients and withholding subsequent doses until hyperfibrinolysis is confirmed by thromboelastography.

Effect of tranexamic acid use on blood loss and thromboembolic risk in hip fracture surgery: systematic review and meta-analysis

INTRODUCTION

Intravenous tranexamic acid (IV TXA) is a recognised pharmaceutical intervention utilised to minimise blood loss and allogenic blood transfusion. However, the use of IV TXA in hip fracture surgery remains inconclusive. We conducted a meta-analysis to investigate the role of TXA in operative hip fracture management on operative and total blood loss, allogenic blood transfusion requirements and impact on venous thromboembolic (VTE) event incidence.

METHODS

A systematic computerised literature search of PubMed, Medline, Embase, Ovid, The Cochrane Controlled Trials Register, Trip and Google was conducted. We reviewed the efficacy of IV TXA on perioperative blood loss, total blood loss, pre- and postoperative haemoglobin differences, duration of surgery, allogenic blood transfusion requirements and VTE events.

RESULTS

8 studies were eligible including 6 randomised control trials and 2 cohort studies. Patients receiving IV TXA had reduced mean total blood loss of 442.9 mls (95% CI, 426.5-459.3; p<0.00001), reduced operative blood loss of 88.5 mls (95% CI, 59.9-117.2; p<0.00001), a decrease in the need for allogenic blood transfusion (OR 0.37; 95% CI, 0.26-0.53; p<0.00001) and a reduction in pre- and postoperative haemoglobin difference (p = 0.013.) There was no significant increase in VTE risk (OR 1.59; 95% CI 0.67-3.75; p>0.29) or significant difference on duration of surgery seen with IV TXA usage (p>0.06).

CONCLUSIONS

Our review demonstrated the efficacy of IV TXA in minimising perioperative, reducing total blood loss and lowering the necessity for allogenic blood transfusions with no significant increased risk in VTE events.

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.

Single intravenous bolus versus perioperative continuous infusion of tranexamic acid to reduce blood loss in abdominal oncosurgical procedures: A prospective randomized double-blind clinical study

Background and Aims:

Intraoperative use of a single bolus dose of tranexamic acid may not be sufficient to prevent bleeding in the early postoperative period. The present study was carried out to compare the effect of two dose regimens of tranexamic acid in reducing perioperative blood loss and the amount of allogenic blood transfusion in abdominal tumor surgery.

Material and Methods:

In this prospective, controlled, and double-blind investigation, 60 patients electively posted for abdominal oncosurgical procedures were randomly assigned to receive a single bolus dose of tranexamic acid (10 mg/kg) (Group A), a bolus dose of tranexamic acid (10 mg/kg) followed by infusion (1 mg/kg/h) till 4 h postoperatively (Group B), and a bolus followed by infusion of normal saline (group C). Total intraoperative blood loss, amount of allogenic blood transfusion, postoperative drain collections, and hemoglobin and hematocrit levels were recorded at different time intervals. Data obtained after comparing three groups were analyzed by analysis of variance test for variables following normal distribution, Kruskal–Wallis test for nonparametric data, and post-hoc Tukey–Kramer test for intergroup analysis. A probability value of less than 5% was considered significant.

Results:

There was no significant difference in intraoperative blood loss in all the three groups. Both the tranexamic acid groups showed reduction in postoperative blood collection in drain at 6 h and 24 h in comparison to the control group (P < 0.001). There was also a significant difference in the amount of blood in postoperative drain at 24 h within the tranexamic acid groups, where lesser collection was seen in the infusion group (P = 0.007). Hemoglobin and hematocrit levels measured at different postoperative time intervals showed a significant reduction from the baseline in the control group compared to the tranexamic acid groups together.

Conclusion:

Tranexamic acid causes more effective reduction in post-operative blood loss when used as a bolus followed by an infusion continued in the postoperative period in comparison to its use as a single intravenous bolus in abdominal tumor surgery.

The effect of prophylactic oral tranexamic acid plus buccal misoprostol on blood loss after vaginal delivery: a randomized controlled trial

OBJECTIVE

The objective of this study is to evaluate the effect of prophylactic oral tranexamic acid (TA) plus buccal misoprostol on the amount of blood loss after vaginal delivery in women at low risk for post-partum hemorrhage (PPH).

MATERIALS AND METHODS

The study was a randomized open label clinical trial conducted in a tertiary University Hospital between January 2016 and June 2017. We included women who delivered vaginally with a singleton pregnancy. They were randomized into three groups: group I (women received 10 IU oxytocin IV after delivery of the baby), group II (women received 600 µg buccal misoprostol after delivery of the baby), and group III (women received 1000 mg oral TA at the end of the first stage of labor plus 600 µg buccal misoprostol after delivery of the baby). In each group, pre- and post-delivery pulse rate, blood pressure, temperature, and hemoglobin level were evaluated. Additionally, the amount of blood loss, need for blood transfusion, need for additional uterotonics, and side effects of the study medications were recorded.

RESULTS

There was a statistically significant lower hemoglobin level and higher blood loss in the misoprostol group compared with oxytocin group and TA plus misoprostol group (p = .0001). There was a statistically significant higher hemoglobin level and lower blood loss in the TA plus misoprostol group compared with the oxytocin group (p = .004 and .043, respectively). PPH occurred in 16.7% of women in the misoprostol group compared 1.7% in the oxytocin group and no cases of PPH in the TA plus misoprostol group (p = .0001).

CONCLUSIONS

In settings like rural area or home delivery in which oxytocin is not available, alternative oral TA plus buccal misoprostol may be considered as an effective line in prevention of PPH.

Effects of a targeted blood management programme on allogeneic blood transfusion in abdominal aortic aneurysm surgery

OBJECTIVES

To investigate the impact of a dedicated cell salvage practitioner team on blood loss and allogeneic transfusion in abdominal aortic aneurysm (AAA) surgery.

BACKGROUND

Cell salvage reduces allogeneic transfusion in AAA surgery, but is commonly performed by the anaesthetic nurse. At our hospital, a dedicated patient blood management practitioner is present for all elective open AAA repairs.

METHODS/MATERIALS

Data were collected on 171 AAA patients operated on at the John Radcliffe Hospital, Oxford over a 3-year period, looking at the Patient Blood Management processes, including: blood loss, cell salvage, near-patient testing (thrombelastography) and transfusion rates of allogeneic blood products.

RESULTS

Blood loss ranged from 3-108% of estimated blood volume (EBV) (median 25% = 1500 mL). In seven patients who lost 70-110% of their EBV, none reached the thrombelastography intervention threshold for R time (11 min) or MA (48 mm) despite such massive blood loss. Overall, only 7/171 (4%) patients received intra-operative allogeneic blood, all of whom had a mean baseline haemoglobin concentration < 106 g L^-1 (median 98, range 95-105 g L^-1 ). In terms of other blood products, only 4/171 (2·3%) received one unit of platelets each intra-operatively. None received FFP or cryoprecipitate.

CONCLUSIONS

Such low levels of allogeneic transfusion have not been reported previously. We hypothesise that this is due to the additional blood management contributions of the specialised cell salvage practitioners and collaboration with the rest of the vascular surgical team. These results support the development of pre-operative anaemia clinics. Overall the service runs at a profit to the trust.

Tranexamic acid reduces blood loss in intertrochanteric fractures: A meta-analysis from randomized controlled trials

BACKGROUND

This meta-analysis aims to assess the efficacy and safety of tranexamic acid for reducing blood loss and transfusion requirements in patients with intertrochanteric fractures.

METHODS

We conduct electronic searches of Medline (1966-2017.09), PubMed (1966-2017.09), Embase (1980-2017.09), ScienceDirect (1985-2017.09), and the Cochrane Library. Only randomized controlled trials (RCTs) are included. The quality assessments are performed according to the Cochrane systematic review method. Fixed/random-effect model is used according to the heterogeneity tested by I statistic. Meta-analysis is performed using Stata 11.0 software.

RESULTS

A total of 4 RCTs are retrieved involving 514 participants. The present meta-analysis indicated that there were significant differences between groups in terms of total blood loss (weighted mean differences = -131.49, 95% confidence interval (CI): -163.63 to -99.35, P = .00), hemoglobin decline (weighted mean differences = -0.31, 95% CI, -0.44 to -0.19, P = .00), and transfusion rate (risk differences = -1.11, 95% CI, -0.19 to -0.04, P = .00). In addition, no increased risk of adverse effects was identified in both groups.

CONCLUSION

Local administration of tranexamic acid is associated with a reduced total blood loss, postoperative hemoglobin decline, and transfusion requirements in patients with intertrochanteric fractures. High-quality RCTs are still required for further investigation.

Multiple boluses of intravenous tranexamic acid to reduce hidden blood loss and the inflammatory response following enhanced-recovery primary total hip arthroplasty: a randomised clinical trial

AIMS

The aim of this study was to examine the efficacy and safety of multiple boluses of intravenous (IV) tranexamic acid (TXA) on the hidden blood loss (HBL) and inflammatory response following primary total hip arthroplasty (THA).

PATIENTS AND METHODS

A total of 150 patients were allocated randomly to receive a single bolus of 20 mg/kg IV TXA before the incision (group A), a single bolus followed by a second bolus of 1 g IV-TXA three hours later (group B) or a single bolus followed by two boluses of 1 g IV-TXA three and six hours later (group C). All patients were treated using a standard peri-operative enhanced recovery protocol. Primary outcomes were HBL and the level of haemoglobin (Hb) as well as the levels of C-reactive protein (CRP) and interleukin-6 (IL-6) as markers of inflammation. Secondary outcomes included the length of stay in hospital and the incidence of venous thromboembolism (VTE).

RESULTS

The mean HBL was significantly lower in group C (402.13 ml standard deviation (sd) 225.97) than group A (679.28 ml sd 277.16, p < 0.001) or B (560.62 ml sd 295.22, p = 0.010). The decrease in the level of Hb between the pre-operative baseline and the level on the third post-operative day was 30.82 g/L (sd 6.31 g/L) in group A, 27.16 g/L (sd 6.83) in group B and 21.98 g/L (sd 3.72) in group C. This decrease differed significantly among the three groups (p < 0.01). The mean level of CRP was significantly lower in group C than in the other two groups on the second (p ≤ 0.034) and third post-operative days (p ≤ 0.014). The levels of IL-6 were significantly lower in group C than group A on the first three post-operative days (p = 0.023). The mean length of stay was significantly lower in group C than group A (p = 0.023). No VTE or other adverse events occurred.

CONCLUSION

Multiple boluses of IV-TXA can effectively reduce HBL following primary THA. A regime of three boluses leads to a smaller decrease in the level of Hb, less post-operative inflammation and a shorter length of stay in hospital than a single bolus. Cite this article: Bone Joint J 2017;99-B:1442-9.

The effect of different dosage regimens of tranexamic acid on blood loss in bimaxillary osteotomy: a randomized, double-blind, placebo-controlled study

The purpose of this study was to compare the effects of three dosage regimens of intravenous tranexamic acid and normal saline placebo on blood loss and the requirement for transfusion during bimaxillary osteotomy. A prospective, randomized, double-blind, placebo-controlled study was performed. Eighty patients scheduled for elective bimaxillary osteotomy were divided into four groups: a placebo group and three groups receiving a single dose of tranexamic acid 10, 15, or 20mg/kg body weight after the induction of anaesthesia. Demographic data, the anaesthetic time, the operative time, and the experience of the surgical team were similar in the four groups. Patients receiving placebo had increased blood loss compared to those receiving tranexamic acid. No significant difference in blood loss was found among those who received 10, 15, or 20mg/kg body weight of tranexamic acid. There was no significant difference in transfusion requirement, amount of 24-h postoperative vacuum drainage, length of hospital stay, or complications among the four groups. Prophylactic tranexamic acid decreased bleeding during bimaxillary osteotomy. Of the three dosages of tranexamic acid studied, the most efficacious and cost-effective dose to reduce bleeding was 10mg/kg body weight.

The effect of tranexamic acid on blood loss and maternal outcome in the treatment of persistent postpartum hemorrhage: A nationwide retrospective cohort study

Background

Recent results show a protective effect of tranexamic acid on death due to bleeding in patients with postpartum hemorrhage in low- and middle-resource countries. We quantify the association between early administration of tranexamic acid compared to late or no administration and severe acute maternal morbidity and blood loss among women suffering from persistent severe postpartum hemorrhage in a high-income country.

Methods and findings

We performed a nationwide retrospective cohort study in 61 hospitals in the Netherlands. The study population consisted of 1260 women with persistent postpartum hemorrhage who had received at least four units of red cells, or fresh frozen plasma or platelets in addition to red cells. A review of medical records was performed and cross-referenced with blood bank data. The composite endpoint comprised maternal morbidity (hysterectomy, ligation of the uterine arteries, emergency B-Lynch suture, arterial embolization or admission into an intensive care unit) and mortality.

Results

247 women received early tranexamic acid treatment. After adjustment for confounding, odds ratio for the composite endpoint for early tranexamic acid (n = 247) versus no/late tranexamic acid (n = 984) was 0.92 (95% confidence interval (CI) 0.66 to 1.27). Propensity matched analysis confirmed the absence of a difference between women with and without tranexamic acid. Blood loss after administration of first line therapy did not differ significantly between the two groups (adjusted difference -177 mL, CI -509.4 to +155.0).

Conclusions

Our findings suggest that in a high-resource country the effect of tranexamic acid on both blood loss and the combined endpoint of maternal mortality and morbidity may be disappointing.

Antifibrinolytics (lysine analogues) for the prevention of bleeding in people with haematological disorders

STATEMENT

The mission of the Cochrane Nursing Care Field (CNCF) is to improve health outcomes through increasing the use of the Cochrane Library and supporting Cochrane's role by providing an evidence base for nurses and healthcare professionals who deliver, lead or research nursing care. The CNCF produces Cochrane Corner columns, summaries of recent nursing-care-relevant Cochrane Reviews that are regularly published in collaborating nursing-related journals. Information on the processes CNCF has developed can be accessed at: cncf.cochrane.org/evidence-transfer-program-review-summaries. This is a Cochrane review summary of: Estcourt LJ, Desborough M, Brunskill SJ et al ( 2016 ) Antifibrinolytics (lysine analogues) for the prevention of bleeding in people with haematological disorders. Cochrane Database of Systematic Reviews. Issue 3. CD009733. doi: 10.1002/14651858.CD009733.pub3.

Perioperative Management of Blood Loss in Spine Surgery

Spine procedures are associated with high rates of blood loss which can result in a greater need for transfusions. Repeated exposure to blood products is associated with risks and adverse reactions such as transfusion-related acute lung injury, fluid shifting, and infections. With the higher number of spine procedures and the increasing open surgery times associated with difficult procedures, excessive blood loss has become more prevalent. Perioperative methods have been established to combat the excessive blood loss and decrease the need for blood products. Preoperatively, anemia and coagulopathy screening is standard at least 4 weeks before elective procedures. Erythropoietin, iron loading or transfusions are used to decrease preoperative anemia, a predisposing factor for blood loss. Autologous predonation of blood has been shown to be ineffective and decreases preoperative hemoglobin levels. Intraoperatively, antifibrinolytics such as tranexamic acid and aminocaproic acid are used to decrease blood loss. In addition, fibrinogen concentrates, thromboelastometry, acute normovolemic hemodilution, controlled hypotension, and temperature regulation are some of the techniques used to decrease blood loss and the need for transfusions. Postoperatively, fibrin sealants, shed blood salvage, and erythropoietin or intravenous iron are used in management of blood loss, especially in instances when the patient refuses blood products.

How I treat heavy menstrual bleeding associated with anticoagulants

Anticoagulant-associated heavy menstrual bleeding (HMB) is an underrecognized but not uncommon problem in clinical practice. Premenopausal women should be advised of the potential effect of anticoagulant therapy on menstrual bleeding at the time of treatment initiation. Consequences of HMB should be assessed and treated on an ongoing basis. In the acute setting, the decision to withhold anticoagulants is based on an individual patient's risk of thrombosis and the severity of the bleeding. For women who require long-term anticoagulation, a levonorgestrel intrauterine system, tranexamic acid (during menstrual flow), high-dose progestin-only therapy, or combined hormonal contraceptives are effective for controlling HMB. The risk of thrombosis during anticoagulant therapy with these treatments is not well studied but is likely to be low. Selection of type of hormonal therapy is based on patient preference, other indications for and contraindications to therapy, adverse effect profile, and ongoing thrombotic risk factors. Women who do not respond to medical treatment or who do not wish to retain their fertility should be considered for surgical management.

Administration of tranexamic acid in trauma patients under stricter inclusion criteria increases the treatment window for stabilization from 24 to 48 hours-a retrospective review

BACKGROUND

Since 2010, the use of Tranexamic Acid (TXA) in trauma has been brought to the forefront of severe hemorrhage treatment. However, the mixed literature illustrates the need for additional proof of efficacy and determining which patients may benefit from TXA. The purpose of this retrospective study was to evaluate a more stringent TXA inclusion criterion (heart rate ≥ 120 beats per minute (BPM) with a systolic blood pressure (SBP) ≤ 90 mmHg) as compared to the standard CRASH-2 inclusion criteria.

METHODS

From 2013-2016 a total of 115 patients (control, n = 62; TXA, n = 53) were included in the analysis. These patients adhered to the standard CRASH-2 and more stringent inclusion criteria; they also survived at least 8.5 hrs (minimum amount of time required for full TXA dose) from the initiation. Basic characteristics of the patients were summarized. The mortality rates between TXA and control groups were compared using two proportion z-tests. All p values <0.05 were considered statistically significant.

RESULTS

There was no statistical significant difference in patient characteristics between the two treatment groups, making them more comparable (p value >0.05). This study found a significant reduction of percent mortality at the 24 hr time point against the control (p = 0.007). Additionally, utilizing the more strict inclusion criteria (BPM ≥ 120 and SBP ≤ 90) substantially extended time to stabilize patients to 48 hrs (p = 0.029).

CONCLUSION

By imposing the more strict criteria, TXA appears to be a better treatment option in reducing mortality rates and potentially extends the treatment time-frame for stabilizing the patient up to 48 hours.

Protocol for a pilot, randomised, double-blinded, placebo-controlled trial of prophylactic use of tranexamic acid for preventing postpartum haemorrhage (TAPPH-1)

INTRODUCTION

Postpartum haemorrhage (PPH) is the leading cause of maternal morbidity and mortality worldwide. Despite the availability of multiple uterotonic agents, the incidence of PPH continues to rise. Tranexamic acid (TXA) has been shown to be a safe, effective and inexpensive therapeutic option for the treatment of PPH, however, its use prophylactically in mitigating the risk of PPH is unknown. This pragmatic randomised prospective trial assesses the feasibility and safety of administering TXA at the time of delivery for the prevention of PPH.

METHODS AND ANALYSIS

A pilot pragmatic randomised double-blinded placebo-controlled trial will be performed. 58 singleton parturients at term >32 weeks, undergoing either spontaneous vaginal delivery, or caesarean section will be randomised to receive 1 g of TXA or placebo (0.9% saline) intravenously. The primary outcome assessed will be the feasibility of administrating TXA, along with collecting data regarding safety of drug administration. The groups will also be analysed on efficacy of mitigating the onset of PPH and clinically relevant variables. Demographic, feasibility, safety and clinical endpoints will be summarised and the appropriate measures of central tendency and dispersion will be presented.

ETHICS AND DISSEMINATION

This protocol was approved by the Sunnybrook Health Sciences Centre Research Ethics Board (number: 418-2016). The results will be disseminated in a peer-reviewed journal and at scientific meetings.

TRIAL REGISTRATION NUMBER

NCT03069859; Pre-results.

Discrepancies between ClinicalTrials.gov recruitment status and actual trial status: a cross-sectional analysis

OBJECTIVES

To determine the accuracy of the recruitment status listed on ClinicalTrials.gov as compared with the actual trial status.

DESIGN

Cross-sectional analysis.

SETTING

Random sample of interventional phase 2-4 clinical trials registered between 2010 and 2012 on ClinicalTrials.gov.

PRIMARY OUTCOME MEASURE

For each trial which was listed within ClinicalTrials.gov as ongoing, two investigators performed a comprehensive literature search for evidence that the trial had actually been completed. For each trial listed as completed or terminated early by ClinicalTrials.gov, we compared the date that the trial was actually concluded with the date the registry was updated to reflect the study's conclusion status.

RESULTS

Among the 405 included trials, 92 had a registry status indicating that study activity was either ongoing or the recruitment status was unknown. Of these, published results were available for 34 (37%). Among the 313 concluded trials, the median delay between study completion and a registry update reflecting that the study had ended was 141 days (IQR 48-419), with delays of over 1 year present for 29%. In total, 125 trials (31%) either had a listed recruitment status which was incorrect or had a delay of more than 1 year between the time the study was concluded and the time the registry recruitment status was updated.

CONCLUSIONS

At present, registry recruitment status information in ClinicalTrials.gov is often outdated or wrong. This inaccuracy has implications for the ability of researchers to identify completed trials and accurately characterise all available medical knowledge on a given subject.

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.

Intravenous Tranexamic Acid Bolus plus Infusion Is Not More Effective than a Single Bolus in Primary Hip Arthroplasty

Background

Preoperative administration of the antifibrinolytic agent tranexamic acid reduces bleeding in patients undergoing hip arthroplasty. Increased fibrinolytic activity is maintained throughout the first day postoperation. The objective of the study was to determine whether additional perioperative administration of tranexamic acid would further reduce blood loss.

Methods

This prospective, double-blind, parallel-arm, randomized, superiority study was conducted in 168 patients undergoing unilateral primary hip arthroplasty. Patients received a preoperative intravenous bolus of 1 g of tranexamic acid followed by a continuous infusion of either tranexamic acid 1 g (bolus-plus-infusion group) or placebo (bolus group) for 8 h. The primary outcome was calculated perioperative blood loss up to day 5. Erythrocyte transfusion was implemented according to a restrictive transfusion trigger strategy.

Results

The mean perioperative blood loss was 919 ± 338 ml in the bolus-plus-infusion group (84 patients analyzed) and 888 ± 366 ml in the bolus group (83 patients analyzed); mean difference, 30 ml (95% CI, −77 to 137; P = 0.58). Within 6 weeks postsurgery, three patients in each group (3.6%) underwent erythrocyte transfusion and two patients in the bolus group experienced distal deep-vein thrombosis. A meta-analysis combining data from this study with those of five other trials showed no incremental efficacy of additional perioperative administration of tranexamic acid.

Conclusions

A preoperative bolus of tranexamic acid, associated with a restrictive transfusion trigger strategy, resulted in low erythrocyte transfusion rates in patients undergoing hip arthroplasty. Supplementary perioperative administration of tranexamic acid did not achieve any further reduction in blood loss.

Diagnostic and therapeutic medical devices for safer blood management in cardiac surgery: systematic reviews, observational studies and randomised controlled trials

Background

Anaemia, coagulopathic bleeding and transfusion are strongly associated with organ failure, sepsis and death following cardiac surgery.

Objective

To evaluate the clinical effectiveness and cost-effectiveness of medical devices used as diagnostic and therapeutic tools for the management of anaemia and bleeding in cardiac surgery.

Methods and results

Workstream 1 – in the COagulation and Platelet laboratory Testing in Cardiac surgery (COPTIC) study we demonstrated that risk assessment using baseline clinical factors predicted bleeding with a high degree of accuracy. The results from point-of-care (POC) platelet aggregometry or viscoelastometry tests or an expanded range of laboratory reference tests for coagulopathy did not improve predictive accuracy beyond that achieved with the clinical risk score alone. The routine use of POC tests was not cost-effective. A systematic review concluded that POC-based algorithms are not clinically effective. We developed two new clinical risk prediction scores for transfusion and bleeding that are available as e-calculators. Workstream 2 – in the PAtient-SPecific Oxygen monitoring to Reduce blood Transfusion during heart surgery (PASPORT) trial and a systematic review we demonstrated that personalised near-infrared spectroscopy-based algorithms for the optimisation of tissue oxygenation, or as indicators for red cell transfusion, were neither clinically effective nor cost-effective. Workstream 3 – in the REDWASH trial we failed to demonstrate a reduction in inflammation or organ injury in recipients of mechanically washed red cells compared with standard (unwashed) red cells.

Limitations

Existing studies evaluating the predictive accuracy or effectiveness of POC tests of coagulopathy or near-infrared spectroscopy were at high risk of bias. Interventions that alter red cell transfusion exposure, a common surrogate outcome in most trials, were not found to be clinically effective.

Conclusions

A systematic assessment of devices in clinical use as blood management adjuncts in cardiac surgery did not demonstrate clinical effectiveness or cost-effectiveness. The contribution of anaemia and coagulopathy to adverse clinical outcomes following cardiac surgery remains poorly understood. Further research to define the pathogenesis of these conditions may lead to more accurate diagnoses, more effective treatments and potentially improved clinical outcomes.

Study registration

Current Controlled Trials ISRCTN20778544 (COPTIC study) and PROSPERO CRD42016033831 (systematic review) (workstream 1); Current Controlled Trials ISRCTN23557269 (PASPORT trial) and PROSPERO CRD4201502769 (systematic review) (workstream 2); and Current Controlled Trials ISRCTN27076315 (REDWASH trial) (workstream 3).

Funding

This project was funded by the National Institute for Health Research (NIHR) Programme Grants for Applied Research programme and will be published in full inProgramme Grants for Applied Research; Vol. 5, No. 17. See the NIHR Journals Library website for further project information.

Tranexamic acid in total hip arthroplasty: A recursive cumulative meta-analysis of randomized controlled trials and assessment of publication bias

INTRODUCTION

TXA has been evaluated in THA in several randomized controlled trials for the past 16 years. We attempted to evaluate the trends in the evidence using recursive cumulative meta-analysis and publication bias using Rosenthal and 'Trim and Fill' methods.

METHODS

Electronic databases were searched for randomized controlled clinical trials comparing TXA with either placebo (or no TXA administration) or TXA, administered through different routes in patients with osteoarthritis or osteonecrosis of the hip who underwent THA. We considered the total number of patients requiring blood transfusion as the clinical outcome for both the analyses and used quality effects model for assessing the changes in the pooled estimates with addition of new clinical trial data. We also assessed the publication bias by plotting individual study estimates with the standard errors using Rosenthal and 'Trim and Fill'methods.

RESULTS

A total of 20 studies were included. The pooled cumulative meta-analysis indicates that from 2014 the addition of estimate from new studies in the following years is only narrowing the confidence interval without any significant change in the point estimate. Rosenthal fail-safe-N for the comparisons of intravenous bolus TXA, intra-operative and post-operative intravenous TXA and topical with control groups were 54, 6 and 16 respectively. Fail-safe-N for the combined intravenous and topical TXA with intravenous TXA alone was 13.

CONCLUSION

Adequate evidence exists supporting the use of intravenous TXA in reducing the need for blood transfusion in THA. There is possible existence of small studies with null effects evaluating the use of TXA in THA.

The Use of Tranexamic Acid for Upper Gastrointestinal Bleeding by Medical and Surgical Intensivists: A Single Center Experience

BACKGROUND

Tranexamic acid (TXA) may be beneficial in the management of upper gastrointestinal bleeding (UGIB). We sought to investigate how frequently intensivists at our academic institution use TXA for patients with UGIB, and to investigate whether the utilization rate of TXA differs between surgical and medical intensivists, and provide an updated literature review on the subject.

METHODS

We performed a retrospective cohort study of patients admitted for UGIB to the surgical intensive care unit (SICU) and the medical intensive care unit (MICU) at our academic healthcare facility (University of Florida Health - Shands Hospital) from January 1, 2013 to December 31, 2016. The patients were categorized as receiving or not receiving TXA. The overall utilization rate of TXA was calculated, and the utilization rates for the MICU and SICU were compared using a two-sample test for equality of two proportions with continuity correction.

RESULTS

The study cohort included a total of 1,829 patients with a diagnosis of UGIB. Of those, 988 were treated in the MICU and 841 were treated in the SICU. Of the 988 patients in the MICU, six received TXA (0.61%), while 10 (1.19%) of the 841 patients in the SICU received TXA. The overall utilization rate of TXA was 0.87%. The odds of receiving TXA in the SICU were 1.97 times greater than in the MICU (odds ratio (OR): 1.97, 95% confidence interval (CI): 0.74 - 5.2, P = 1.83).

CONCLUSIONS

Our study suggests that TXA may be underused in the management of UGIB, and that the utilization rate does not differ significantly between surgical and medical intensivists.

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.

Zika Virus and Patient Blood Management

Sporadic Zika virus infections had only occurred in Africa and Asia until an outbreak in Micronesia (Oceania) in 2007. In 2013 to 2014, several outer Pacific Islands reported local outbreaks. Soon thereafter, the virus was likely introduced in Brazil from competing athletes from French Polynesia and other countries that participated in a competition there. Transmission is thought to have occurred through mosquito bites and spread to the immunologically naive population. Being also a flavivirus, the Zika virus is transmitted by the Aedes mosquito that is endemic in South and Central America that is also the vector of West Nile virus, dengue, and chikungunya. In less than a year, physicians in Brazil reported a many-fold increase in the number of babies born with microcephaly. Despite initial skepticism regarding the causal association of the Zika virus epidemic and birth defects, extensive basic and clinical research evidence has now confirmed this relationship. In the United States, more than 4000 travel-associated infections have been reported by the middle of 2016 to the Centers for Disease Control and Prevention. Furthermore, many local mosquito-borne infections have occurred in Puerto Rico and Florida. Considering that the virus causes a viremia in which 80% of infected individuals have no symptoms, the potential for transfusion transmission from an asymptomatic blood donor is high if utilizing donor screening alone without testing. Platelet units have been shown to infect 2 patients via transfusion in Brazil. Although there was an investigational nucleic acid test available for testing donors, not all blood centers were initially required to participate. Subsequently, the US Food and Drug Administration issued a guidance in August 2016 that recommended universal nucleic acid testing for the Zika virus on blood donors.In this report, we review the potentially devastating effects of Zika virus infection during pregnancy and its implication in cases of Guillain-Barre syndrome in adults. Furthermore, we urge hospital-based clinicians and transfusion medicine specialists to implement perisurgical patient blood management strategies to avoid blood component transfusions with their potential risks of emerging pathogens, illustrated here by the Zika virus. Ultimately, this current global threat, as described by the World Health Organization, will inevitably be followed by future outbreaks of other bloodborne pathogens; the principles and practices of perioperative patient blood management will reduce the risks from not only known, but also unknown risks of blood transfusion for our patients.

Desmopressin use for minimising perioperative blood transfusion

BACKGROUND

Blood transfusion is administered during many types of surgery, but its efficacy and safety are increasingly questioned. Evaluation of the efficacy of agents, such as desmopressin (DDAVP; 1-deamino-8-D-arginine-vasopressin), that may reduce perioperative blood loss is needed.

OBJECTIVES

To examine the evidence for the efficacy of DDAVP in reducing perioperative blood loss and the need for red cell transfusion in people who do not have inherited bleeding disorders.

SEARCH METHODS

We searched for randomised controlled trials (RCTs) in the Cochrane Central Register of Controlled Trials (2017, issue 3) in the Cochrane Library, MEDLINE (from 1946), Embase (from 1974), the Cumulative Index to Nursing and Allied Health Literature (CINAHL) (from 1937), the Transfusion Evidence Library (from 1980), and ongoing trial databases (all searches to 3 April 2017).

SELECTION CRITERIA

We included randomised controlled trials comparing DDAVP to placebo or an active comparator (e.g. tranexamic acid, aprotinin) before, during, or immediately after surgery or after invasive procedures in adults or children.

DATA COLLECTION AND ANALYSIS

We used the standard methodological procedures expected by Cochrane.

MAIN RESULTS

We identified 65 completed trials (3874 participants) and four ongoing trials. Of the 65 completed trials, 39 focused on adult cardiac surgery, three on paediatric cardiac surgery, 12 on orthopaedic surgery, two on plastic surgery, and two on vascular surgery; seven studies were conducted in surgery for other conditions. These trials were conducted between 1986 and 2016, and 11 were funded by pharmaceutical companies or by a party with a commercial interest in the outcome of the trial.The GRADE quality of evidence was very low to moderate across all outcomes. No trial reported quality of life. DDAVP versus placebo or no treatmentTrial results showed considerable heterogeneity between surgical settings for total volume of red cells transfused (low-quality evidence) and for total blood loss (very low-quality evidence) due to large differences in baseline blood loss. Consequently, these outcomes were not pooled and were reported in subgroups.Compared with placebo, DDAVP may slightly decrease the total volume of red cells transfused in adult cardiac surgery (mean difference (MD) -0.52 units, 95% confidence interval (CI) -0.96 to -0.08 units; 14 trials, 957 participants), but may lead to little or no difference in orthopaedic surgery (MD -0.02, 95% CI -0.67 to 0.64 units; 6 trials, 303 participants), vascular surgery (MD 0.06, 95% CI -0.60 to 0.73 units; 2 trials, 135 participants), or hepatic surgery (MD -0.47, 95% CI -1.27 to 0.33 units; 1 trial, 59 participants).DDAVP probably leads to little or no difference in the total number of participants transfused with blood (risk ratio (RR) 0.96, 95% CI 0.86 to 1.06; 25 trials; 1806 participants) (moderate-quality evidence).Whether DDAVP decreases total blood loss in adult cardiac surgery (MD -135.24 mL, 95% CI -210.80 mL to -59.68 mL; 22 trials, 1358 participants), orthopaedic surgery (MD -285.76 mL, 95% CI -514.99 mL to -56.53 mL; 5 trials, 241 participants), or vascular surgery (MD -582.00 mL, 95% CI -1264.07 mL to 100.07 mL; 1 trial, 44 participants) is uncertain because the quality of evidence is very low.DDAVP probably leads to little or no difference in all-cause mortality (Peto odds ratio (pOR) 1.09, 95% CI 0.51 to 2.34; 22 trials, 1631 participants) or in thrombotic events (pOR 1.36, 95% CI, 0.85 to 2.16; 29 trials, 1984 participants) (both low-quality evidence). DDAVP versus placebo or no treatment for people with platelet dysfunctionCompared with placebo, DDAVP may lead to a reduction in the total volume of red cells transfused (MD -0.65 units, 95% CI -1.16 to -0.13 units; 6 trials, 388 participants) (low-quality evidence) and in total blood loss (MD -253.93 mL, 95% CI -408.01 mL to -99.85 mL; 7 trials, 422 participants) (low-quality evidence).DDAVP probably leads to little or no difference in the total number of participants receiving a red cell transfusion (RR 0.83, 95% CI 0.66 to 1.04; 5 trials, 258 participants) (moderate-quality evidence).Whether DDAVP leads to a difference in all-cause mortality (pOR 0.72, 95% CI 0.12 to 4.22; 7 trials; 422 participants) or in thrombotic events (pOR 1.58, 95% CI 0.60 to 4.17; 7 trials, 422 participants) is uncertain because the quality of evidence is very low. DDAVP versus tranexamic acidCompared with tranexamic acid, DDAVP may increase the volume of blood transfused (MD 0.6 units, 95% CI 0.09 to 1.11 units; 1 trial, 40 participants) and total blood loss (MD 142.81 mL, 95% CI 79.78 mL to 205.84 mL; 2 trials, 115 participants) (both low-quality evidence).Whether DDAVP increases or decreases the total number of participants transfused with blood is uncertain because the quality of evidence is very low (RR 2.42, 95% CI 1.04 to 5.64; 3 trials, 135 participants).No trial reported all-cause mortality.Whether DDAVP leads to a difference in thrombotic events is uncertain because the quality of evidence is very low (pOR 2.92, 95% CI 0.32 to 26.83; 2 trials, 115 participants). DDAVP versus aprotininCompared with aprotinin, DDAVP probably increases the total number of participants transfused with blood (RR 2.41, 95% CI 1.45 to 4.02; 1 trial, 99 participants) (moderate-quality evidence).No trials reported volume of blood transfused or total blood loss and the single trial that included mortality as an outcome reported no deaths.Whether DDAVP leads to a difference in thrombotic events is uncertain because the quality of evidence is very low (pOR 0.98, 95% CI 0.06 to 15.89; 2 trials, 152 participants).

AUTHORS' CONCLUSIONS

Most of the evidence derived by comparing DDAVP versus placebo was obtained in cardiac surgery, where DDAVP was administered after cardiopulmonary bypass. In adults undergoing cardiac surgery, the reduction in volume of red cells transfused and total blood loss was small and was unlikely to be clinically important. It is less clear whether DDAVP may be of benefit for children and for those undergoing non-cardiac surgery. A key area for researchers is examining the effects of DDAVP for people with platelet dysfunction. Few trials have compared DDAVP versus tranexamic acid or aprotinin; consequently, we are uncertain of the relative efficacy of these interventions.

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.

[Postoperative excessive blood loss after cardiac surgery can be predicted with International Society on Thrombosis and Hemostasis scoring system]

BACKGROUND AND OBJECTIVE

Prediction of postoperative excessive blood loss is useful for management of Intensive Care Unit after cardiac surgery. The aim of present study was to examine the effectiveness of International Society on Thrombosis and Hemostasis scoring system in patients with cardiac surgery.

METHOD

After obtaining approval from the institutional review board, the medical records of patients undergoing elective cardiac surgery using Cardio-Pulmonary Bypass between March 2010 and February 2014 were retrospectively reviewed. International Society on Thrombosis and Hemostasis score was calculated in intensive care unit and patients were divided with overt disseminated intravascular coagulation group and non-overt disseminated intravascular coagulation group. To evaluate correlation with estimated blood loss, student t-test and correlation analyses were used.

RESULTS

Among 384 patients with cardiac surgery, 70 patients with overt disseminated intravascular coagulation group (n=20) or non-overt disseminated intravascular coagulation group (n=50) were enrolled. Mean disseminated intravascular coagulation scores at intensive care unit admission was 5.35±0.59 (overt disseminated intravascular coagulation group) and 2.66±1.29 (non-overt disseminated intravascular coagulation group) and overt disseminated intravascular coagulation was induced in 29% (20/70). Overt disseminated intravascular coagulation group had much more EBL for 24h (p=0.006) and maintained longer time of intubation time (p=0.005).

CONCLUSION

In spite of limitation of retrospective design, management using International Society on Thrombosis and Hemostasis score in patients after cardiac surgery seems to be helpful for prediction of the post- cardio-pulmonary bypass excessive blood loss and prolonged tracheal intubation duration.

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.

Intraoperative tranexamic acid is associated with postoperative stroke in patients undergoing cardiac surgery

BACKGROUND

Stroke is a devastating and potentially preventable complication of cardiac surgery. Tranexamic acid (TXA) is a commonly antifibrinolytic agent in cardiac surgeries with cardiopulmonary bypass (CPB), however, there is concern that it might increase incidence of stroke after cardiac surgery. In this retrospective study, we investigated whether TXA usage could increase postoperative stroke in cardiac surgery.

METHODS

A retrospective study was conducted from January 1, 2010, to December 31, 2015, in 2,016 patients undergoing cardiac surgery, 664 patients received intravenous TXA infusion and 1,352 patients did not receive any antifibrinolytic agent. Univariate and propensity-weighted multivariate regression analysis were applied for data analysis.

RESULTS

Intraoperative TXA administration was associated with postoperative stroke (1.7% vs. 0.5%; adjusted OR, 4.11; 95% CI, 1.33 to 12.71; p = 0.014) and coma (adjusted OR, 2.77; 95% CI, 1.06 to 7.26; p = 0.038) in cardiac surgery. As subtype analysis was performed, TXA administration was still associated with postoperative stroke (1.7% vs. 0.3%; adjusted OR, 5.78; 95% CI, 1.34 to 27.89; p = 0.018) in patients undergoing valve surgery or multi-valve surgery only, but was not associated with postoperative stroke (1.7% vs. 1.3%; adjusted OR, 5.21; 95% CI, 0.27 to 101.17; p = 0.276) in patients undergoing CABG surgery only. However, TXA administration was not associated with postoperative mortality (adjusted OR, 1.31; 95% CI, 0.56 to 3.71; p = 0.451), seizure (adjusted OR, 1.13; 95% CI, 0.42 to 3.04; p = 0.816), continuous renal replacement therapy (adjusted OR, 1.36; 95% CI, 0.56 to 3.28; p = 0.495) and resternotomy for postoperative bleeding (adjusted OR, 1.55; 95% CI, 0.55 to 4.30; p = 0.405). No difference was found in postoperative ventilation time (adjusted B, -1.45; SE, 2.33; p = 0.535), length of intensive care unit stay (adjusted B, -0.12; SE, 0.25; p = 0.633) and length of hospital stay (adjusted B, 0.48; SE, 0.58; p = 0.408).

CONCLUSIONS

Based on the 5-year experience of TXA administration in cardiac surgery with CPB, we found that postoperative stroke was associated with intraoperative TXA administration in patients undergoing cardiac surgery, especially in those undergoing valve surgeries only. This study may suggest that TXA should be administrated according to clear indications after evaluating the bleeding risk in patients undergoing cardiac surgery, especially in those with high stroke risk.

Hyperfibrinolysis and Hypofibrinogenemia Diagnosed With Rotational Thromboelastometry in Dogs Naturally Infected With Angiostrongylus vasorum

Background

The pathomechanism of Angiostrongylus vasorum infection‐associated bleeding diathesis in dogs is not fully understood.

Objective

To describe rotational thromboelastometry (ROTEM) parameters in dogs naturally infected with A. vasorum and to compare ROTEM parameters between infected dogs with and without clinical signs of bleeding.

Animals

A total of 21 dogs presented between 2013 and 2016.

Methods

Dogs with A. vasorum infection and ROTEM evaluation were retrospectively identified. Thrombocyte counts, ROTEM parameters, clinical signs of bleeding, therapy, and survival to discharge were retrospectively retrieved from patient records and compared between dogs with and without clinical signs of bleeding.

Results

Evaluation by ROTEM showed hyperfibrinolysis in 8 of 12 (67%; 95% CI, 40–86%) dogs with and 1 of 9 (11%; 95% CI, 2–44%) dogs without clinical signs of bleeding (P = .016). Hyperfibrinolysis was associated with severe hypofibrinogenemia in 6 of 10 (60%; 95% CI, 31–83%) of the cases. Hyperfibrinolysis decreased or resolved after treatment with 10–80 mg/kg tranexamic acid. Fresh frozen plasma (range, 14–60 mL/kg) normalized follow‐up fibrinogen function ROTEM (FIBTEM) maximal clot firmness in 6 of 8 dogs (75%; 95% CI, 41–93%). Survival to discharge was 67% (14/21 dogs; 95% CI, 46–83%) and was not different between dogs with and without clinical signs of bleeding (P = .379).

Conclusion and Clinical Importance

Hyperfibrinolysis and hypofibrinogenemia were identified as an important pathomechanism in angiostrongylosis‐associated bleeding in dogs. Hyperfibrinolysis and hypofibrinogenemia were normalized by treatment with tranexamic acid and plasma transfusions, respectively.

Treatment of Persistent Gross Hematuria with Tranexamic Acid in Autosomal Dominant Polycystic Kidney Disease

BACKGROUND/AIMS

In this retrospective study we aimed to compare the effect of tranexamic acid (TXA) vs etamsylate, two hemostatic agents, on hematuria duration in autosomal dominant polycystic kidney disease (ADPKD) patients with persistent gross hematuria.

METHODS

This is a retrospective study of 40 patients with ADPKD and macroscopic hematuria. 20 patients receiving TXA and snake venom blood clotting enzyme injection were compared with 20 matched patients receiving etamsylate and snake venom blood clotting enzyme injection. The primary outcome was hematuria duration and the secondary outcomes were blood transfusion requirements and adverse events.

RESULTS

The hematuria duration was shorter in the TXA group compared with the etamsylate group (4[3-5] d vs 7[6-10] d, P<0.001). The volume of blood transfusion tended to be less in the TXA group than in the etamsylate group (300±115 ml vs 486±195 ml, P=0.12), and the number of patients needing a blood transfusion also tended to be lower [20% (4/20) vs 35% (7/20), P=0.29]. TXA and etamsylate were equally well tolerated and no serious adverse events were observed in both groups.

CONCLUSIONS

Our study indicates that TXA treatment was more effective than etamsylate in stopping bleeding in ADPKD patients with persistent gross hematuria.

The impact of hemocoagulase for improvement of coagulation and reduction of bleeding in fracture-related hip hemiarthroplasty geriatric patients: A prospective, single-blinded, randomized, controlled study

BACKGROUND

Uncontrolled bleeding is associated with poor outcomes and mortality in geriatric patients undergoing hemiarthroplasty. Hemocoagulase agkistrodon is a hemocoagulative, anti-hemorrhagic enzyme complex from Deinagkistrodon acutus snake venom. This study aimed to investigate the efficacy of hemocoagulase agkistrodon on coagulation and bleeding outcomes in fracture-related hemiarthroplasty.

PATIENTS AND METHODS

This was a prospective, single-blinded, randomized controlled trial carried out between October 2013 and September 2014 in 96 geriatric patients undergoing hemiarthroplasty for unilateral femoral neck fracture. Patients were administrated hemocoagulase agkistrodon (n=48) or normal saline (n=48). Intraoperative blood loss, transfusion volume and rate, and drainage were assessed. Hemoglobin (Hb) and coagulation parameters (prothrombin time [PT], thrombin time [TT], plasma fibrinogen [FIB], and activated partial thromboplastin time [aPTT]) were recorded preoperatively and 30min and 1, 3, and 5days after surgery. Complications were followed up for 4 weeks.

RESULTS

Compared to controls, hemocoagulase patients exhibited lower intraoperative blood loss (P<0.01) and postoperative blood loss, total drainage, mean transfusion volume, and transfusion rates (all P<0.05), with lower aPTT at 30min (P<0.05). No significant differences in postoperative FIB were observed. Controls exhibited significantly higher PP and TT on day 1, and Hb on days 1, 3, and 5 (P<0.05). No serious complications were reported.

CONCLUSIONS

Hemocoagulase reduced blood loss and transfusion in fracture-related hip hemiarthroplasty without increasing short-term adverse event rates. In geriatric populations, hemocoagulase could be used for limiting bleeding and related complications.

TRIAL REGISTRATION

This trial is registered in the Chinese Clinical Trial Register (no. ChiCTR-TRC-14004379).

Low Risk of Thromboembolic Events After Routine Administration of Tranexamic Acid in Hip and Knee Arthroplasty

BACKGROUND

The blood-conserving effect of intravenous (IV) tranexamic acid (TXA) is well-documented for total hip arthroplasty (THA) and total knee arthroplasty (TKA). However, the risk of thromboembolic (TE) events after routine use of TXA is unclear and the safety profile is debated. This retrospective study investigates patient characteristics, occurrences, and predictors of TE events after routine administration of IV TXA in THA and TKA.

METHODS

Three thousand one hundred fifty-nine THA or TKA procedures performed from 2007-2013 at our institution were included. IV TXA, 1 g, was administered preoperatively if not contraindicated. Relevant patient characteristics and comorbidity information were extracted locally from the database. Data on TE events occurring within 90 days postoperatively came from The Danish National Patient Registry. Patient characteristics, comorbidities, and TE events were compared between TXA groups. A logistic regression model was used to evaluate predictors of TE events.

RESULTS

Of 3159 procedures, 2766 (87.6%) received TXA (TXA+ group) preoperatively, whereas 393 (12.4%) did not (TXA- group). Mean age, distributions of gender, American Society of Anesthesiologists score, anesthesia method, duration of surgery, diagnosis, and survival status were all statistically significant different (P values <.05) between TXA groups. The studied comorbidities were all significantly different (TXA+ vs TXA- group; P values ≤.002). We found 31 (1.0%) TE events out of 3159 procedures, with no significant group difference in TE events (TXA+: 27 out of 2766 = 1.0%, TXA-: 4 out of 393 = 1.0%, P value = .55 for any event). For the TXA+ group, 0.5% suffered from deep venous thrombosis, 0.3% from acute myocardial infarction, and 0.2% from a pulmonary embolism. In the TXA+ group, higher age (odds ratio [OR] = 1.06, 95% confidence interval = 1.02-1.11, P = .005) and present cardiovascular disease (OR = 4.78, 95% confidence interval = 1.72-13.28, P = .003) were associated with an increased risk of TE events.

CONCLUSION

The findings suggest that routine use of IV TXA for TKA and THA as safe with low occurrence of TE events, although a large prospective trial should confirm this.

Tranexamic Acid Update in Trauma

Following results from the CRASH-2 trial, tranexamic acid (TXA) gained considerable interest for the treatment of hemorrhage in trauma patients. Although TXA is effective at reducing mortality in patients presenting within 3 hours of injury, optimal dosing, timing of administration, mechanism, and pharmacokinetics require further elucidation. The concept of fibrinolysis shutdown in hemorrhagic trauma patients has prompted discussion of real-time viscoelastic testing and its potential role for appropriate patient selection. The results of ongoing clinical trials will help establish high-quality evidence for optimal incorporation of TXA in mature trauma networks in the United States and abroad.

Massive transfusion: An update for the anesthesiologist

Exsanguination from trauma, gastrointestinal bleeding, and obstetric hemorrhage remains a major source of mortality across the planet. Continued research into resuscitation strategies and evolving technology and blood product storage has allowed for patient to undergo very large volume transfusions, even to the point of replacing a patient’s blood volume several times over. As massive transfusions have become more common, more studies have been performed delineating the exact patient population that would benefit, start- and stop-points of transfusions, complications and avoidance of the same. We discuss these points and provide information and strategies for massive transfusion.