Tranexamic acid for the prevention of postpartum hemorrhage in women undergoing cesarean delivery: an updated meta-analysis

Prophylactic tranexamic acid in Cesarean delivery: an updated meta-analysis with a trial sequential analysis

PURPOSE

Postpartum hemorrhage (PPH) is a leading cause of maternal mortality worldwide. Although several studies on the prophylactic use of tranexamic acid (TXA) in parturients undergoing Cesarean delivery have been published, conflicting results raise questions regarding its use. Thus, we aimed to investigate the safety and efficacy of PPH prophylaxis with TXA.

SOURCE

We searched PubMed®, Embase, Cochrane Central, and ClinicalTrials.gov for randomized controlled trials (RCTs) comparing prophylactic TXA with placebo or no treatment in parturients undergoing Cesarean delivery. Our main outcomes were PPH, any blood transfusion, need for additional uterotonics, and adverse events. We performed a trial sequential analysis (TSA) of all outcomes to investigate the reliability and conclusiveness of findings.

PRINCIPAL FINDINGS

We included 38 RCTs including 22,940 parturients, 11,535 (50%) of whom were randomized to receive prophylactic TXA. Patients treated with TXA had significantly fewer cases of PPH (risk ratio [RR], 0.51; 95% confidence interval [CI], 0.38 to 0.69; P < 0.001); less blood transfusion (RR, 0.43; 95% CI, 0.30 to 0.61; P < 0.001), and less use of additional uterotonics (RR, 0.52; 95% CI, 0.40 to 0.68; P < 0.001). No significant differences were found between the groups in terms of adverse effects and thromboembolic events.

CONCLUSION

Prophylactic TXA administration for parturients undergoing Cesarean delivery significantly reduced blood loss, without increasing adverse events, supporting its use as a safe and effective strategy for reducing PPH in this population.

STUDY REGISTRATION

PROSPERO (CRD42023422188); first submitted 27 April 2023.

Uterine packing with chitosan-covered tamponade to treat postpartum hemorrhage

Postpartum hemorrhage remains a major cause of maternal mortality and morbidity worldwide with higher rates found in resource-challenged countries. Conventional use of uterotonics such as oxytocin, prostaglandins, and medications to support coagulation, such as fibrinogen and tranexamic acid, are helpful but may not be sufficient to arrest life-threatening postpartum hemorrhage. Severe postpartum hemorrhage leads to an increased need for blood transfusions and the use of invasive techniques, such as intrauterine balloon tamponade, compression sutures, and arterial ligation, as advanced steps in the management cascade. In extreme cases where hemorrhage is resistant to these therapies, a hysterectomy may be necessary to avoid possible maternal death. Uterine packing with a chitosan-covered tamponade is an emerging tool in the armamentarium of the obstetrical team, especially when resources for advance surgical and other invasive options may be limited. Modified chitosan-impregnated gauze was originally described in the management of acute hemorrhage in the field of military medicine, combining the physiological antihemorrhaging effect of modified chitosan with a compression tamponade for the acute treatment of wound bleeding. The first described use in obstetrics was in 2012, showing that the chitosan-covered tamponade is an effective intervention to arrest ongoing therapy-resistant postpartum hemorrhage. Further studies showed a reduction in hysterectomies and blood transfusions. The method is, however, underreported and is not yet an established method used worldwide. To demonstrate the step-by-step application of the intrauterine chitosan-covered tamponade in the management of therapy-resistant postpartum hemorrhage, we have produced a teaching video to illustrate the important steps and techniques to optimize the effectiveness and safety of this novel intervention.

Third stage of labor: evidence-based practice for prevention of adverse maternal and neonatal outcomes

The third stage of labor is defined as the time period between delivery of the fetus through delivery of the placenta. During a normal third stage, uterine contractions lead to separation and expulsion of the placenta from the uterus. Postpartum hemorrhage is a relatively common complication of the third stage of labor. Strategies have been studied to mitigate the risk of postpartum hemorrhage, leading to the widespread implementation of active management of the third stage of labor. Initially, active management of the third stage of labor consisted of a bundle of interventions including administration of a uterotonic agent, early cord clamping, controlled cord traction, and external uterine massage. However, the effectiveness of these interventions as a bundle has been questioned, leading to abandonment of some components in recent years. Despite this, upon review of selected international guidelines, we found that the term "active management of the third stage of labor" was still used, but recommendations for and against individual interventions were variable and not necessarily supported by current evidence. In this review, we: (1) examine the physiology of the third stage of labor, (2) present evidence related to interventions that prevent postpartum hemorrhage and promote maternal and neonatal health, (3) review current global guidelines and recommendations for practice, and (4) propose future areas of investigation. The interventions in this review include pharmacologic agents to prevent postpartum hemorrhage, cord clamping, cord milking, cord traction, cord drainage, early skin-to-skin contact, and nipple stimulation. Treatment of complications of the third stage of labor is outside of the scope of this review. We conclude that current evidence supports the use of effective pharmacologic postpartum hemorrhage prophylaxis, delayed cord clamping, early skin-to-skin contact, and controlled cord traction at delivery when feasible. The most effective uterotonic regimens for preventing postpartum hemorrhage after vaginal delivery include oxytocin plus ergometrine; oxytocin plus misoprostol; or carbetocin. After cesarean delivery, carbetocin or oxytocin as a bolus are the most effective regimens. There is inconsistent evidence regarding the use of tranexamic acid in addition to a uterotonic compared with a uterotonic alone for postpartum hemorrhage prevention after all deliveries. Because of differences in patient comorbidities, costs, and availability of resources and staff, decisions to use specific prevention strategies are dependent on patient- and system-level factors. We recommend that the term "active management of the third stage of labor" as a combined intervention no longer be used. Instead, we recommend that "third stage care" be adopted, which promotes the implementation of evidence-based interventions that incorporate practices that are safe and beneficial for both the woman and neonate.

Risk factors of massive blood transfusion (MTP) in cesarean hysterectomy for placenta accreta spectrum

BACKGROUND

Placenta Accreta Spectrum (PAS) represents a particularly morbid condition for which blood transfusion is the leading cause. Delivery by cesarean hysterectomy is recommended for the management of PAS. Massive Transfusion Protocols (MTP) in obstetrics vary in definition and implementation. Given the significant blood loss during PAS cesarean hysterectomy, this is particularly important for surgeons and blood banks. Our objective was to identify risk factors for MTP in patients with antenatally suspected PAS.

METHODS

We performed a case-control study over a 11-year period from 2012 to 2022 at our center for Placenta Accreta Spectrum. MTP was defined by two methods, >4 units or > 10 units of red blood cells/whole blood transfused over 24 h. Antenatal, operative and post-operative outcomes were obtained from electronic medical records of these cases.

RESULTS

During the study time frame, 142 cases were managed by our PAS team and met all criteria. 85 % (120/142) of patients were transfused at least 1 unit of blood, 64 patients (45 %) received 0-3 units of blood, 50 patients (35 %) received 4-9 units of blood and 28 patients (19.7 %) were transfused > 10 units of blood. Pre-delivery vaginal bleeding, preterm labor and delivery < 34 weeks were independently significant in transfused patients. ROC analysis revealed an area under the curve (AUC) of 0.79 (p < 0.0001) in patients transfused > 10 units, showing predictive capability for this subgroup.

DISCUSSION

We here report pre-operative risk factors for MTP in patients undergoing cesarean hysterectomy for PAS. This allows for both resource utilization and patient counseling for this morbid maternal condition.

Awareness and use of tranexamic acid in the management of postpartum hemorrhage among health care professionals in Enugu, Nigeria

OBJECTIVES

This study was conducted to determine the knowledge, practice, and barriers regarding the use of tranexamic acid (TXA) for the prevention and treatment of postpartum hemorrhage (PPH) among health care providers in Enugu, Nigeria.

METHODS

A cross-sectional study was conducted among health professionals (doctors, pharmacists, and nurses) in two Nigerian tertiary teaching hospitals (one federal and one state). A total of 220 questionnaires were distributed and 207 were returned (response rate: 94%) and analyzed using SPSS for inferential statistics with a level of significance of P < 0.05.

RESULTS

Only 23.7% of the respondents had good knowledge of TXA use in PPH (P < 0.001), and awareness of the recent World Health Organization (WHO) recommendation on the use of TXA for PPH was low (19.8%, P < 0.001). The majority of the respondents had neither prescribed nor dispensed TXA (30%, P < 0.001). Very few respondents used TXA for all cases of PPH (16.4%, P < 0.001). Barriers against its use include nonawareness of the latest WHO recommendation, preference for other uterotonics, and cost of the drug.

CONCLUSIONS

There was poor knowledge of TXA, poor awareness of its recommendation, and low use for PPH among different cadres of health care providers.

Efficacy and safety of tranexamic acid in prevention of postpartum hemorrhage: a systematic review and meta-analysis of 18,649 patients

BACKGROUND

In this meta-analysis, we aimed to update the clinical evidence regarding the efficacy and safety of TXA in the prevention of PPH.

METHODS

A literature search of PubMed, Scopus, Web of Science, Google Scholar, and Cochrane Library from inception until December 2022 was conducted. We included randomized controlled trials (RCTs) comparing TXA with a placebo among pregnant women. All relevant outcomes, such as total blood loss, the occurrence of nausea and/or vomiting, and changes in hemoglobin, were combined as odds ratios (OR) or mean differences (MD) in the meta-analysis models using STATA 17 MP.

RESULTS

We included 59 RCTs (18,649 patients) in this meta-analysis. For cesarean birth, TXA was favored over the placebo in reducing total blood loss (MD= -2.11 mL, 95%CI [-3.09 to -1.14], P < 0.001), and occurrence of nausea or/and vomiting (OR = 1.36, 95%CI [1.07 to 1.74], P = 0.01). For vaginal birth, the prophylactic use of TXA was associated with lower total blood loss, and higher occurrence of nausea and/or vomiting (MD= -0.89 mL, 95%CI [-1.47 to -0.31], OR = 2.36, 95%CI [1.32 to 4.21], P = 0.02), respectively. However, there were no differences between the groups in changes in hemoglobin during vaginal birth (MD = 0.20 g/dl, 95%CI [-0.07 to 0.48], P = 0.15). The overall risk of bias among the included studies varies from low to high risk of bias using ROB-II tool for RCTs.

CONCLUSIONS

This meta-analysis suggested that TXA administration is effective among women undergoing cesarean birth or vaginal birth in lowering total blood loss and limiting the occurrence of PPH. Further clinical trials are recommended to test its efficacy on high-risk populations.

Tranexamic acid for reduction of blood loss after Caesarean delivery: a cost-effectiveness analysis of the TRAAP2 trial

BACKGROUND

Prophylactic administration of tranexamic acid is associated with a reduction of blood loss after Caesarean delivery, but cost-effectiveness for this indication has not been assessed.

METHODS

We used data from the TRAAP2 trial, a multicentre, double-blinded, RCT aimed at estimating the efficacy of tranexamic acid for preventing postpartum haemorrhage among women undergoing Caesarean delivery. Women recruited at 27 French maternity hospitals from 2018 to 2020 were enrolled before the procedure if they had a Caesarean delivery before or during labour at 34 or more weeks of gestation. The main outcomes were the cost of hospital stay for delivery and the incremental cost per delivery without complication within 90 days after delivery with tranexamic acid compared with placebo. Differences in costs and the incremental net monetary benefit (INMB) were estimated using linear regression models, and the cost-effectiveness probability of tranexamic acid compared with placebo was estimated through the parametric distribution of the INMB.

RESULTS

The proportion of women without complications at day 90 was 70.7% in the tranexamic acid group and 66.0% in the placebo group. Mean total costs until occurrence of a complication of interest were €3321 in the tranexamic acid group and €3260 in the placebo group, resulting in a difference between the two groups of 7.2% and €55 after multiple imputation. The adjusted incremental cost-effectiveness ratio was €762 per additional Caesarean delivery without a complication at 90 days after delivery. At a cost-effectiveness threshold of €10,000, the cost-effectiveness probability of tranexamic acid compared with placebo was 99.9%, varying from 5.8% to 100.0% for thresholds from €0 to €10,000 per additional delivery without a complication at day 90.

CONCLUSION

Tranexamic acid for the prevention of blood loss is cost-effective in reducing complications after Caesarean delivery at day 90 postpartum. However, the effect size (in cost and effectiveness) is very low.

CLINICAL TRIAL REGISTRATION

NCT03431805.

Placenta previa percreta with surrounding organ involvement: a proposal for management

Placenta accreta spectrum encompasses cases where the placenta is morbidly adherent to the myometrium. Placenta percreta, the most severe form of placenta accreta spectrum (grade 3E), occurs when the placenta invades through the myometrium and possibly into surrounding structures next to the uterine corpus. Maternal morbidity of placenta percreta is high, including severe maternal morbidity in 82.1% and mortality in 1.4% in the recent nationwide U.S. statistics. Although cesarean hysterectomy is commonly performed for patients with placenta accreta spectrum, conservative management is becoming more popular because of reduced morbidity in select cases. Treatment of grade 3E disease involving the urinary bladder, uterine cervix, or parametria is surgically complicated due to the location of the invasive placenta deep in the maternal pelvis. Cesarean hysterectomy in this setting has the potential for catastrophic hemorrhage and significant damage to surrounding organs. We propose a step-by-step schema to evaluate cases of grade 3E disease and determine whether immediate hysterectomy or conservative management, including planned delayed hysterectomy, is the most appropriate treatment option. The approach includes evaluation in the antenatal period with ultrasound and magnetic resonance imaging to determine suspicion for placenta previa percreta with surrounding organ involvement, planned cesarean delivery with a multidisciplinary team including experienced pelvic surgeons such as a gynecologic oncologist, intra-operative assessment including gross surgical field exposure and examination, cystoscopy, and consideration of careful intra-operative transvaginal ultrasound to determine the extent of placental invasion into surrounding organs. This evaluation helps decide the safety of primary cesarean hysterectomy. If safely resectable, additional considerations include intra-operative use of uterine artery embolization combined with tranexamic acid injection in cases at high risk for pelvic hemorrhage and ureteral stent placement. Availability of resuscitative endovascular balloon occlusion of the aorta is ideal. If safe resection is concerned, conservative management including planned delayed hysterectomy at around 4 weeks from cesarean delivery in stable patients is recommended.

Comparison of quantitative and calculated postpartum blood loss after vaginal delivery

BACKGROUND

Because there is no consensus on the method of assessing postpartum blood loss, the comparability and relevance of the postpartum hemorrhage-related literature are questionable. Quantitative blood loss assessment using a volumetric technique with a graduated collector bag has been proposed to overcome limitations of intervention-based outcomes but remains partly subjective and potentially biased by amniotic fluid or missed out-of-bag losses. Calculated blood loss based on laboratory parameters has been studied and used as an objective method expected to reflect total blood loss. However, few studies have compared quantitative with calculated blood loss.

OBJECTIVE

This study aimed to compare the distribution of postpartum blood loss after vaginal delivery assessed by 2 methods-quantitative and calculated blood loss-and the incidence of abnormal blood loss with each method.

STUDY DESIGN

Data were obtained from the merged database of 3 multicenter, randomized controlled trials, all testing different interventions to prevent postpartum blood loss in individuals with a singleton live fetus at ≥35 weeks of gestation, born vaginally. All 3 trials measured blood loss volume by using a graduated collector bag. Hematocrit was measured in the eighth or ninth month of gestation and on day 2 postpartum. The 2 primary outcomes were: quantitative blood loss, defined by the total volume of blood loss measured in a graduated collector bag, and calculated blood loss, mathematically defined from the peripartum hematocrit change (estimated blood volume × [(antepartum hematocrit-postpartum hematocrit)/antepartum hematocrit], where estimated blood volume [mL]=booking weight [kg] × 85). We modeled the association between positive quantitative blood loss and positive calculated blood loss with polynomial regression and calculated the Spearman correlation coefficient.

RESULTS

Among the 8341 individuals included in this analysis, the median quantitative blood loss (100 mL; interquartile range, 50-275) was significantly lower than the median calculated blood loss (260 mL; interquartile range, 0-630) (P<.05). The incidence of abnormal blood loss was lower with quantitative blood loss than calculated blood loss for all 3 thresholds: for ≥500 mL, it was 9.6% (799/8341) and 32.3% (2691/8341), respectively; for ≥1000 mL, 2.1% (176/8341) and 11.5% (959/8341); and for ≥2000 mL, 0.1% (10/8341) and 1.4% (117/8341) (P<.05). Quantitative blood loss and calculated blood loss were significantly but moderately correlated (Spearman coefficient=0.44; P<.05). The association between them was not linear, and their difference tended to increase with blood loss. Negative calculated blood loss values occurred in 23% (1958/8341) of individuals; among them, >99% (1939/1958) had quantitative blood loss ≤500 mL.

CONCLUSION

Quantitative and calculated blood loss were significantly but moderately correlated after vaginal delivery. However, clinicians should be aware that quantitative blood loss is lower than calculated blood loss, with a difference that tended to rise as blood loss increased.

Prophylactic Administration of Tranexamic Acid Reduces Blood Products' Transfusion and Intensive Care Admission in Women Undergoing High-Risk Cesarean Sections

Postpartum hemorrhage (PPH) remains a major cause of maternal mortality. Tranexamic acid (TxA) has shown effectiveness in reducing PPH-related maternal bleeding events and deaths. We conducted a cohort study including parturient women at high risk of bleeding after undergoing a cesarean section (CS). Participants were divided into two groups: the treatment group received prophylactic 1-g TxA before surgery (n = 500), while the comparison group underwent CS without TxA treatment (n = 500). The primary outcome measured increased maternal blood loss following CS, defined as more than a 10% drop in hemoglobin concentration within 24 h post-CS and/or a drop of ≥2 g/dL in maternal hemoglobin concentration. Secondary outcomes included PPH indicators, ICU admission, hospital stay, TxA complications, and neonatal data. TxA administration significantly reduced hemoglobin decrease by more than 10%: there was a 35.4% decrease in the TxA group vs. a 59.4% decrease in the non-TxA group, p < 0.0001 and hemoglobin decreased by ≥2 g/dL (11.4% in the TxA group vs. 25.2% in non-TxA group, p < 0.0001), reduced packed red blood cell transfusion (p = 0.0174), and resulted in lower ICU admission rates (p = 0.034) and shorter hospitalization (p < 0.0001). Complication rates and neonatal outcomes did not differ significantly. In conclusion, prophylactic TxA administration during high-risk CS may effectively reduce blood loss, providing a potential intervention to improve maternal outcomes.

Novel concepts and improvisation for treating postpartum haemorrhage: a narrative review of emerging techniques

BACKGROUND

Most treatments for postpartum haemorrhage (PPH) lack evidence of effectiveness. New innovations are ubiquitous but have not been synthesized for ready access.

NARRATIVE REVIEW

Pubmed 2020 to 2021 was searched on 'postpartum haemorrhage treatment', and novel reports among 755 citations were catalogued. New health care strategies included early diagnosis with a bundled first response and home-based treatment of PPH. A calibrated postpartum blood monitoring tray has been described. Oxytocin is more effective than misoprostol; addition of misoprostol to oxytocin does not improve treatment. Heat stable carbetocin has not been assessed for treatment. A thermostable microneedle oxytocin patch has been developed. Intravenous tranexamic acid reduces mortality but deaths have been reported from inadvertent intrathecal injection. New transvaginal uterine artery clamps have been described. Novel approaches to uterine balloon tamponade include improvised and purpose-designed free-flow (as opposed to fixed volume) devices and vaginal balloon tamponade. Uterine suction tamponade methods include purpose-designed and improvised devices. Restrictive fluid resuscitation, massive transfusion protocols, fibrinogen use, early cryopreciptate transfusion and point-of-care viscoelastic haemostatic assay-guided blood product transfusion have been reported. Pelvic artery embolization and endovascular balloon occlusion of the aorta and pelvic arteries are used where available. External aortic compression and direct compression of the aorta during laparotomy or aortic clamping (such as with the Paily clamp) are alternatives. Transvaginal haemostatic ligation and compression sutures, placental site sutures and a variety of novel compression sutures have been reported. These include Esike's technique, three vertical compression sutures, vertical plus horizontal compression sutures, parallel loop binding compression sutures, uterine isthmus vertical compression sutures, isthmic circumferential suture, circumferential compression sutures with intrauterine balloon, King's combined uterine suture and removable retropubic uterine compression suture. Innovative measures for placenta accreta spectrum include a lower uterine folding suture, a modified cervical inversion technique, bilateral uterine artery ligation with myometrial excision of the adherent placenta and cervico-isthmic sutures or a T-shaped lower segment repair. Technological advances include cell salvage, high frequency focussed ultrasound for placenta increta and extra-corporeal membrane oxygenation.

CONCLUSIONS

Knowledge of innovative methods can equip clinicians with last-resort options when faced with haemorrhage unresponsive to conventional methods.

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

OBJECTIVE

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

DATA SOURCES

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

STUDY ELIGIBILITY CRITERIA

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

METHODS

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

RESULTS

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

CONCLUSION

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

Blood Product Replacement for Postpartum Hemorrhage

Consideration for blood products replacement in postpartum hemorrhage should be given when blood loss exceeds 1.5 L or when an estimated 25% of blood has been lost. In cases of massive hemorrhage, standardized transfusion protocols have been shown to improve maternal morbidity and mortality. Most protocols recommend a balanced transfusion involving a 1:1:1 ratio of packed red blood cells, platelets, and fresh frozen plasma. Alternatives such as cryoprecipitate, fibrinogen concentrate, and prothrombin complex concentrates can be used in select clinical situations. Although transfusion of blood products can be lifesaving, it does have associated risks.

Postpartum Hemorrhage and Tranexamic Acid: A Literature Review

This review aims to explore the postpartum hemorrhage (PPH) burden and the efficacy of prophylactic tranexamic acid (TXA) in PPH and recent indications of TXA. A comprehensive review of the literature was conducted using a combination of Medical Subject Headings keywords including "Postpartum haemorrhage," "Tranexamic acid," and "Cesarean section." PPH has been explored for epidemiology, risk factors, and pathophysiology in the first part of the article. Recent indications of TXA, obstetric indications, and the role of TXA as prophylaxis for PPH are discussed in the second part of this article. TXA has many indications apart from obstetric indications and shows a significant effect in controlling bleeding. Furthermore, TXA is more efficient in preventing PPH if administered during the final stage of labor and is a valuable option for managing obstetric bleeding.

Tranexamic Acid to Prevent Obstetrical Hemorrhage after Cesarean Delivery

BACKGROUND

Prophylactic use of tranexamic acid at the time of cesarean delivery has been shown to decrease the calculated blood loss, but the effect on the need for blood transfusions is unclear.

METHODS

We randomly assigned patients undergoing cesarean delivery at 31 U.S. hospitals to receive either tranexamic acid or placebo after umbilical-cord clamping. The primary outcome was a composite of maternal death or blood transfusion by hospital discharge or 7 days post partum, whichever came first. Key secondary outcomes were estimated intraoperative blood loss of more than 1 liter (prespecified as a major secondary outcome), interventions for bleeding and related complications, the preoperative-to-postoperative change in the hemoglobin level, and postpartum infectious complications. Adverse events were assessed.

RESULTS

A total of 11,000 participants underwent randomization (5529 to the tranexamic acid group and 5471 to the placebo group); scheduled cesarean delivery accounted for 50.1% and 49.2% of the deliveries in the respective groups. A primary-outcome event occurred in 201 of 5525 participants (3.6%) in the tranexamic acid group and in 233 of 5470 (4.3%) in the placebo group (adjusted relative risk, 0.89; 95.26% confidence interval [CI], 0.74 to 1.07; P = 0.19). Estimated intraoperative blood loss of more than 1 liter occurred in 7.3% of the participants in the tranexamic acid group and in 8.0% of those in the placebo group (relative risk, 0.91; 95% CI, 0.79 to 1.05). Interventions for bleeding complications occurred in 16.1% of the participants in the tranexamic acid group and in 18.0% of those in the placebo group (relative risk, 0.90; 95% CI, 0.82 to 0.97); the change in the hemoglobin level was -1.8 g per deciliter and -1.9 g per deciliter, respectively (mean difference, -0.1 g per deciliter; 95% CI, -0.2 to -0.1); and postpartum infectious complications occurred in 3.2% and 2.5% of the participants, respectively (relative risk, 1.28; 95% CI, 1.02 to 1.61). The frequencies of thromboembolic events and other adverse events were similar in the two groups.

CONCLUSIONS

Prophylactic use of tranexamic acid during cesarean delivery did not lead to a significantly lower risk of a composite outcome of maternal death or blood transfusion than placebo. (Funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development; ClinicalTrials.gov number, NCT03364491.).

Current Evidence on Vasa Previa without Velamentous Cord Insertion or Placental Morphological Anomalies (Type III Vasa Previa): Systematic Review and Meta-Analysis

Vasa previa carries a high risk of severe fetal morbidity and mortality due to fetal hemorrhage caused by damage to unprotected fetal cord vessels upon membrane rupture. Vasa previa is generally classified into types I and II. However, some cases are difficult to classify, and some studies have proposed a type III classification. This study aimed to review the current evidence on type III vasa previa. A systematic literature search was conducted, and 11 articles (2011-2022) were included. A systematic review showed that type III vasa previa accounts for 5.7% of vasa previa cases. Thirteen women with type III vasa previa were examined at a patient-level analysis. The median age was 35 (interquartile range [IQR] 31.5-38) years, and approximately 45% were assisted reproductive technology (ART) pregnancies. The median gestational week of delivery was 36 (IQR 34-37) weeks; the antenatal detection rate was 84.6%, and no cases reported neonatal death. The characteristics and obstetric outcomes (rate of ART, antenatal diagnosis, emergent cesarean delivery, gestational age at delivery, and neonatal mortality) were compared between types I and III vasa previa, and all outcomes of interest were similar. The current evidence on type III vasa previa is scanty, and further studies are warranted.

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

BACKGROUND

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

OBJECTIVE

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

STUDY DESIGN

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

RESULTS

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

CONCLUSION

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

Tranexamic acid administered during cesarean delivery in high-risk patients: maternal pharmacokinetics, pharmacodynamics, and coagulation status

BACKGROUND

Tranexamic acid is frequently administered for postpartum hemorrhage. The World Health Organization recommends 1 g intravenous dosing, repeated once after 30 minutes for ongoing bleeding. Understanding the pharmacokinetics and pharmacodynamics of tranexamic acid in patients at high risk of postpartum hemorrhage may enable dosage tailoring for optimal antifibrinolysis with minimal adverse events, such as thrombosis or renal cortical necrosis.

OBJECTIVE

This study aimed to report tranexamic acid pharmacokinetics and pharmacodynamics after 1 g intravenous dosing during cesarean delivery in patients at risk of hemorrhage. The primary endpoint was tranexamic acid plasma concentration of >10 μg/mL, known to inhibit 80% of fibrinolysis. In addition, the correlation between patient demographics and rotational thromboelastometry coagulation changes were analyzed.

STUDY DESIGN

In this prospective study, 20 women aged 18 to 50 years, ≥23 weeks of gestation undergoing cesarean delivery with at least 1 major (placenta previa, suspected placenta accreta spectrum, or active bleeding) or 2 minor (≥2 previous cesarean deliveries, previous postpartum hemorrhage, chorioamnionitis, polyhydramnios, macrosomia, obesity, or suspected placental abruption) risk factors for postpartum hemorrhage were recruited. The exclusion criteria were allergy to tranexamic acid, inherited thrombophilia, previous or current thrombosis, seizure history, renal or liver dysfunction, anticoagulation, or category III fetal heart tracing. Tranexamic acid 1 g was administered after umbilical cord clamping. Blood samples were drawn at 3, 7, 15, and 30 minutes and then at 30-minute intervals up to 5 hours. Plasma concentrations were evaluated as mean (standard error). Serial rotational thromboelastometry was performed and correlated with tranexamic acid plasma concentrations.

RESULTS

The median age of participants was 37.5 years (interquartile range, 35.0-39.5), and the median body mass index was 28.6 kg/m2 (interquartile range, 24.9-35.0). The median blood loss (estimated or quantitative) was 1500 mL (interquartile range, 898.5-2076.0). Of note, 9 of 20 (45%) received a transfusion of packed red blood cells. The mean peak tranexamic acid plasma concentration at 3 minutes was 59.8±4.7 μg/mL. All patients had a plasma concentration >10 μg/mL for 1 hour after infusion. Plasma concentration was >10 μg/mL in more than half of the patients at 3 hours and fell <10 μg/mL in all patients at 5 hours. There was a moderate negative correlation between body mass index and the plasma concentration area under the curve (r=-0.49; 95% confidence interval, -0.77 to -0.07; P=.026). Rotational thromboelastometry EXTEM maximum clot firmness had a weak positive correlation with longitudinal plasma concentration (r=0.32; 95% confidence interval, 0.21-0.46; P<.001). EXTEM maximum clot lysis was 0% after infusion in 18 patients (90%), and no patient in the study demonstrated a maximum lysis of >15% at any interval from 3 minutes to 5 hours. There was no significant correlation between EXTEM clot lysis at 30 minutes and longitudinal tranexamic acid plasma concentrations (r=0.10; 95% confidence interval, -0.20 to 0.19; P=.252).

CONCLUSION

After standard 1 g intravenous dosing of tranexamic acid during cesarean delivery in patients at high risk of hemorrhage, a plasma concentration of ≥10 μg/mL was sustained for at least 60 minutes. Plasma tranexamic acid levels correlated inversely with body mass index. The concurrent use of rotational thromboelastometry may demonstrate tranexamic acid's impact on clot firmness but not a hyperfibrinolysis-derived trigger for therapy.

Antifibrinolytics in the treatment of traumatic brain injury

PURPOSE OF REVIEW

Traumatic brain injury (TBI) is a leading cause of trauma-related deaths, and pharmacologic interventions to limit intracranial bleeding should improve outcomes. Tranexamic acid reduces mortality in injured patients with major systemic bleeding, but the effects of antifibrinolytic drugs on outcomes after TBI are less clear. We therefore summarize recent evidence to guide clinicians on when (not) to use antifibrinolytic drugs in TBI patients.

RECENT FINDINGS

Tranexamic acid is the only antifibrinolytic drug that has been studied in patients with TBI. Several recent studies failed to conclusively demonstrate a benefit on survival or neurologic outcome. A large trial with more than 12 000 patients found no significant effect of tranexamic acid on head-injury related death, all-cause mortality or disability across the overall study population, but observed benefit in patients with mild to moderate TBI. Observational evidence signals potential harm in patients with isolated severe TBI.

SUMMARY

Given that the effect of tranexamic acid likely depends on a variety of factors, it is unlikely that a 'one size fits all' approach of administering antifibrinolytics to all patients will be helpful. Tranexamic acid should be strongly considered in patients with mild to moderate TBI and should be avoided in isolated severe TBI.

Prophylactic tranexamic acid to reduce blood loss and related morbidities during hysterectomy: a systematic review and meta-analysis of randomized controlled trials

To perform a systematic review and meta-analysis of all randomized controlled trials (RCTs) that evaluated the efficacy and safety of prophylactic tranexamic acid (TXA) versus a control (placebo or no treatment) during hysterectomy for benign conditions. Six databases were screened from inception to January 23, 2022. Eligible studies were assessed for risk of bias. Outcomes were summarized as weighted mean differences and risk ratios with 95% confidence intervals in a random-effects model. Five studies, comprising six arms and 911 patients were included in the study. Two and three studies had an overall unclear and low risk of bias, respectively. Estimated intraoperative blood loss, requirement for postoperative blood transfusion, and requirement for intraoperative topical hemostatic agents were significantly reduced in a prophylactic TXA group when compared with a control group. Moreover, postoperative hemoglobin level was significantly higher in the prophylactic TXA group than in the control group. Conversely, the frequency of self-limiting nausea and vomiting was significantly higher in the prophylactic TXA group than in the control group. There were no significant differences between the groups in terms of surgery duration, hospital stay, and diarrhea rate. All the RCTs reported no incidence of major adverse events in either group, such as mortality, thromboembolic events, visual disturbances, or seizures. There was no publication bias for any outcome, and leave-one-out sensitivity analyses demonstrated stability of the findings. Among patients who underwent hysterectomy for benign conditions, prophylactic TXA appeared largely safe and correlated with substantial reductions in estimated intraoperative blood loss and related morbidities.

Tranexamic Acid for Prevention of Hemorrhage in Elective Repeat Cesarean Delivery - A Randomized Study

BACKGROUND

The American College of Obstetricians and Gynecologists states that data is insufficient to recommend Tranexamic acid (TXA) prophylaxis for postpartum hemorrhage.

OBJECTIVE

This study's objective was to evaluate if prophylactic TXA reduces calculated blood loss versus placebo in women undergoing elective repeat cesarean delivery.

STUDY DESIGN

A double-blind, randomized, placebo-controlled trial, examining calculated blood loss with prophylactic doses of 1-gram of TXA given before skin incision and after placental delivery and standard uterotonics in women with singleton pregnancies at least 37 weeks' gestation, presenting for their second or third cesarean delivery under neuraxial anesthesia. The primary outcome was calculated blood loss at 24 hours. The calculation was based on the participant's height, weight, and the difference in hematocrit before the start of surgery and 24 hours after delivery. Prespecified secondary outcomes were quantification of maternal coagulation activity during the perioperative course. A sample size of 50 women per group was planned (N=100), based on a meta-analysis of mean reduction in blood loss after TXA.

RESULTS

723 women were screened, and 110 women were randomized as follows: 55 to TXA and 55 to placebo. The primary outcome of mean calculated blood for TXA (2274 ± 469 mL) and the placebo group (2407 ± 388 mL), p > 0.05. In the secondary outcomes, D-dimer levels were lower in the TXA group than the placebo group 24 hours after delivery (2.1 ± 1.2 µg/mL versus 4.3 ± 2.4 µg/mL), p < 0.001.

CONCLUSIONS

Prophylactic tranexamic acid did not decrease mean calculated blood loss. Significantly less participants had calculated blood loss greater than 2000 mL in the tranexamic acid group compared to the placebo group with lower levels of D-dimer at 24 hours.