Heat-Stable Carbetocin versus Oxytocin to Prevent Hemorrhage after Vaginal Birth

Modeling the economic burden of postpartum hemorrhage due to substandard uterotonics in Ghana

Uterotonics are essential in preventing postpartum hemorrhage (PPH), the leading direct cause of maternal death worldwide. However, uterotonics are often substandard in low- and middle-income countries, contributing to poor maternal health outcomes. This study examines the health and economic impact of substandard uterotonics in Ghana. A decision-tree model was built to simulate vaginal and cesarean section births across health facilities, uterotonic quality and utilization, PPH risk and diagnosis, and resulting health and economic outcomes. We utilized delivery data from Ghana's maternal health survey, risks of health outcomes from a Cochrane review, and E-MOTIVE trial data for health outcomes related to oxytocin quality. We compared scenarios with and without substandard uterotonics, as well as scenarios altering uterotonic use and care-seeking behaviors. We found that substandard uterotonic use contributes to $18.8 million in economic burden annually, including $6.3 million and $4.8 million in out-of-pocket expenditures in public and private sectors, respectively. Annually, the National Health Insurance Scheme bears $1.6 million in costs due to substandard uterotonic use. Substandard uterotonics contribute to $6 million in long-term productivity losses from maternal mortality annually. Improving the quality of uterotonics could reduce 20,000 (11%) PPH cases, 5,000 (11%) severe PPH cases, and 100 (11%) deaths due to PPH annually in Ghana. Ensuring the quality of uterotonics would result in millions of dollars in cost savings and improve maternal health outcomes for the government and families in Ghana. Cost savings from improving uterotonic quality would provide financial protection and help Ghana advance toward Universal Health Coverage.

Strategies for optimising early detection and obstetric first response management of postpartum haemorrhage at caesarean birth: a modified Delphi-based international expert consensus

OBJECTIVE

There are no globally agreed on strategies on early detection and first response management of postpartum haemorrhage (PPH) during and after caesarean birth. Our study aimed to develop an international expert's consensus on evidence-based approaches for early detection and obstetric first response management of PPH intraoperatively and postoperatively in caesarean birth.

DESIGN

Systematic review and three-stage modified Delphi expert consensus.

SETTING

International.

POPULATION

Panel of 22 global experts in PPH with diverse backgrounds, and gender, professional and geographic balance.

OUTCOME MEASURES

Agreement or disagreement on strategies for early detection and first response management of PPH at caesarean birth.

RESULTS

Experts agreed that the same PPH definition should apply to both vaginal and caesarean birth. For the intraoperative phase, the experts agreed that early detection should be accomplished via quantitative blood loss measurement, complemented by monitoring the woman's haemodynamic status; and that first response should be triggered once the woman loses at least 500 mL of blood with continued bleeding or when she exhibits clinical signs of haemodynamic instability, whichever occurs first. For the first response, experts agreed on immediate administration of uterotonics and tranexamic acid, examination to determine aetiology and rapid initiation of cause-specific responses. In the postoperative phase, the experts agreed that caesarean birth-related PPH should be detected primarily via frequently monitoring the woman's haemodynamic status and clinical signs and symptoms of internal bleeding, supplemented by cumulative blood loss assessment performed quantitatively or by visual estimation. Postoperative first response was determined to require an individualised approach.

CONCLUSION

These agreed on proposed approaches could help improve the detection of PPH in the intraoperative and postoperative phases of caesarean birth and the first response management of intraoperative PPH. Determining how best to implement these strategies is a critical next step.

Uterotonics, magnesium sulphate and antibiotics during childbirth and peripartum: Important obstetric drugs for the anaesthesiologist

The main causes of maternal mortality are comorbidities, hypertensive pregnancy syndrome, obstetric haemorrhage, and maternal sepsis. For this reason, uterotonics, magnesium sulphate, and antibiotics are essential tools in the management of obstetric patients during labour and in the peripartum period. These drugs are widely used by anaesthesiologists in all departments, and play a crucial role in treatment and patient safety. For the purpose of this narrative review, we performed a detailed search of medical databases and selected studies describing the use of these drugs in patients during pregnancy, delivery and the pospartum period. Uterotonics, above all oxytocin, play an important role in the prevention and treatment of pospartum haemorrhage, and various studies have shown that in obstetric procedures, such as scheduled and emergency caesarean section, they are effective at lower doses than those hitherto accepted. We also discuss the use of carbetocin as an effective alternative that has a therapeutic advantage in certain clinical circumstances. Magnesium sulphate is the gold standard in the prevention and treatment of eclampsia, and also plays a neuroprotective role in preterm infants. We describe the precautions to be taken during magnesium administration. Finally, we discuss the importance of understanding microbiology and the pharmacology of antibiotics in the management of obstetric infection and endometritis, and draw attention to the latest trends in antibiotic regimens in labour and caesarean section.

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.

Shock index as a predictor of postpartum haemorrhage after vaginal delivery: Secondary analysis of a multicentre randomised controlled trial

OBJECTIVE

To describe the shock index (SI) distribution during the first 2 hours after delivery and to evaluate its performance when measured 15 and 30 minutes after delivery for predicting postpartum haemorrhage (PPH) occurrence in the general population of parturients after vaginal delivery.

DESIGN

Secondary analysis of a multicentre randomised controlled trial testing prophylactic administration of tranexamic acid versus placebo in addition to prophylactic oxytocin to prevent PPH.

SETTING

15 French maternity units in 2015-2016.

SAMPLE

3891 women with a singleton live fetus ≥35 weeks, born vaginally.

METHODS

For each PPH-related predicted outcome, we calculated the area under the receiver operating characteristic curve (AUROC) values of the SI at 15 and 30 minutes after delivery and its predictive performance for SI cut-off values of 0.7, 0.9 and 1.1.

MAIN OUTCOME MEASURES

Quantitative blood loss ≥1000 ml (QBL ≥1000 ml) measured in a graduated collector bag and provider-assessed clinically significant PPH (cPPH).

RESULTS

Prevalence of QBL ≥1000 ml and cPPH was respectively 2.7% (104/3839) and 9.1% (354/3891). The distributions of the SI at 15 and 30 minutes after delivery were similar with a median value of 0.73 and 97th percentile of 1.11 for both. The AUROC values of the 15-minute SI for discriminating QBL ≥1000 ml and cPPH were respectively 0.66 (lower limit of the 95% confidence interval [LCI] 0.60) and 0.56 (LCI 0.52); and for the 30-minute SI 0.68 (LCI 0.61) and 0.49 (LCI 0.43).

CONCLUSIONS

The shock index at 15 and 30 minutes after delivery did not satisfactorily predict either QBL ≥1000 ml or clinical PPH.

Heat stable carbetocin or oxytocin for prevention of postpartum hemorrhage among women at risk: A secondary analysis of the CHAMPION trial

OBJECTIVE

To examine whether the observed non-inferiority of heat-stable carbetocin (HSC), compared with oxytocin, was influenced by biologic (macrosomia, parity 3 or more, or history of postpartum hemorrhage [PPH]) and/or pharmacologic (induction or augmentation) risk factors for PPH.

METHODS

The present study is a secondary analysis of the CHAMPION non-inferiority randomized trial-a two-arm, double-blind, active-controlled study conducted at 23 hospitals in 10 countries, between July 2015 and January 2018. Women with singleton pregnancies, expected to deliver vaginally with cervical dilatation up to 6 cm were eligible. Randomization was stratified by country, with 1:1 assignment. Women in the intervention and control groups received a single intramuscular injection of 100 μg of HSC or 10 IU of oxytocin, respectively. The drugs were administered immediately after birth, and the third stage of labor was managed according to the WHO guidelines. Blood was collected using a plastic drape. For this analysis, we defined a woman as being at risk if she had any one or more of the biologic or pharmacologic risk factor(s).

RESULTS

The HSC and oxytocin arms contained 14 770 and 14 768 women, respectively. The risk ratios (RR) for PPH were 1.29 (95% confidence interval [CI] 1.08-1.53) or 1.73 (95% CI 1.51-1.98) for those with only biologic (macrosomia, parity 3 or more, and PPH in the previous pregnancy) or only pharmacologic (induced or augmented) risk factors, respectively, compared with those with neither risk factors.

CONCLUSIONS

Findings reinforce previous evidence that macrosomia, high parity, history of PPH, and induction/augmentation are risk factors for PPH. We did not find a difference in effects between HSC and oxytocin for PPH among women who were neither induced nor augmented or among those who were induced or augmented.

Cardiovascular effects of oxytocin and carbetocin at cesarean section. A prospective double-blind randomized study using noninvasive pulse wave analysis

BACKGROUND

Oxytocin is routinely administered after delivery for prophylaxis and treatment of postpartum hemorrhage, but it is associated with considerable cardiovascular side-effects. Carbetocin, a synthetic oxytocin analogue, has a myometrial contraction effect of 60 min when given IV, compared with 16 min for oxytocin.

OBJECTIVE

To investigate whether there are differences in cardiovascular effects between oxytocin and carbetocin up to 1 h after treatment.

METHODS

Sixty-one healthy pregnant women undergoing elective cesarean section in spinal anesthesia were randomized to receive an IV bolus of either five units (8.3 µg) of oxytocin or 100 µg of carbetocin after delivery of the baby. Heart rate (HR), mean arterial blood pressure, ECG ST index, oxygen saturation (SaO₂), and photoplethysmographic digital pulse wave analysis variables were recorded before and at 1, 5, 20, and 60 min after drug administration. Vasopressor use, uterine tonus, total bleeding, and need for additional uterotonics were also assessed. Repeated measurement ANOVA was used for statistical analyses.

RESULTS

The drugs had equal vasodilatory and hypotensive effects. Oxytocin, but not carbetocin, caused a decrease in HR at 1 min and a sustained decrease in cardiac left ventricular ejection time. Aggregate vasopressor use was higher in the carbetocin group. Neither drug caused any change in ST index, SaO₂, or subjective cardiac symptoms. Uterine tonus, need for additional uterotonics, or total bleeding did not differ significantly between the groups.

CONCLUSION

Single doses of oxytocin and carbetocin had similar dilatory effects on vascular tonus, where the difference in aggregate vasopressor use can be attributed to a more persistent hypotensive effect of carbetocin. A transient negative chronotropic and sustained negative inotropic effect occurred after oxytocin. Neither drug showed any alarmingly adverse effects. Differences in drug effects may be attributed to differences in oxytocin and vasopressin receptor signaling pathways.

Perceptions and experiences of the prevention, detection, and management of postpartum haemorrhage: a qualitative evidence synthesis

BACKGROUND

Postpartum haemorrhage (PPH), defined as blood loss of 500 mL or more after childbirth, is the leading cause of maternal mortality worldwide. It is possible to prevent complications of PPH with timely and appropriate detection and management. However, implementing the best methods of PPH prevention, detection and management can be challenging, particularly in low- and middle-income countries.

OBJECTIVES

Our overall objective was to explore the perceptions and experiences of women, community members, lay health workers, and skilled healthcare providers who have experience with PPH or with preventing, detecting, and managing PPH, in community or health facility settings.

SEARCH METHODS

We searched MEDLINE, CINAHL, Scopus, and grey literature on 13 November 2022 with no language restrictions. We then performed reference checking and forward citation searching of the included studies.

SELECTION CRITERIA

We included qualitative studies and mixed-methods studies with an identifiable qualitative component. We included studies that explored perceptions and experiences of PPH prevention, detection, and management among women, community members, traditional birth attendants, healthcare providers, and managers.

DATA COLLECTION AND ANALYSIS

We used three-stage maximum variation sampling to ensure diversity in terms of relevance of the study to the review objectives, richness of data, and coverage of critical contextual elements: setting (region, country income level), perspective (type of participant), and topic (prevention, detection, management). We extracted data using a data extraction form designed for this review. We used thematic synthesis to analyse and synthesise the evidence, and we used the GRADE-CERQual (Confidence in the Evidence from Reviews of Qualitative research) approach to assess our confidence in each finding. To identify factors that may influence intervention implementation, we mapped each review finding to the Theoretical Domains Framework (TDF) and the Capability, Motivation, and Opportunity model of Behaviour change (COM-B). We used the Behaviour Change Wheel to explore implications for practice.

MAIN RESULTS

We included 67 studies and sampled 43 studies for our analysis. Most were from low- or middle-income countries (33 studies), and most included the perspectives of women and health workers. We downgraded our confidence in several findings from high confidence to moderate, low, or very-low confidence, mainly due to concerns about how the studies were conducted (methodological limitations) or concerns about missing important perspectives from some types of participants or in some settings (relevance). In many communities, bleeding during and after childbirth is considered "normal" and necessary to expel "impurities" and restore and cleanse the woman's body after pregnancy and birth (moderate confidence). In some communities, people have misconceptions about causes of PPH or believe that PPH is caused by supernatural powers or evil spirits that punish women for ignoring or disobeying social rules or for past mistakes (high confidence). For women who give birth at home or in the community, female family members or traditional birth attendants are the first to recognise excess bleeding after birth (high confidence). Family members typically take the decision of whether and when to seek care if PPH is suspected, and these family members are often influenced by trusted traditional birth attendants or community midwives (high confidence). If PPH is identified for women birthing at home or in the community, decision-making about the subsequent referral and care pathway can be multifaceted and complex (high confidence). First responders to PPH are not always skilled or trained healthcare providers (high confidence). In health facilities, midwives may consider it easy to implement visual estimation of blood loss with a kidney dish or under-pad, but difficult to accurately interpret the amount of blood loss (very low confidence). Quantifying (rather than estimating) blood loss may be a complex and contentious change of practice for health workers (low confidence). Women who gave birth in health facilities and experienced PPH described it as painful, embarrassing, and traumatic. Partners or other family members also found the experience stressful. While some women were dissatisfied with their level of involvement in decision-making for PPH management, others felt health workers were best placed to make decisions (moderate confidence). Inconsistent availability of resources (drugs, medical supplies, blood) causes delays in the timely management of PPH (high confidence). There is limited availability of misoprostol in the community owing to stockouts, poor supply systems, and the difficulty of navigating misoprostol procurement for community health workers (moderate confidence). Health workers described working on the maternity ward as stressful and intense due to short staffing, long shifts, and the unpredictability of emergencies. Exhausted and overwhelmed staff may be unable to appropriately monitor all women, particularly when multiple women are giving birth simultaneously or on the floor of the health facility; this could lead to delays in detecting PPH (moderate confidence). Inadequate staffing, high turnover of skilled health workers, and appointment of lower-level cadres of health workers are key challenges to the provision of quality PPH care (high confidence). Through team-based simulation training, health workers of different cadres (doctors, midwives, lay health workers) can develop a shared mental model to help them work quickly, efficiently, and amicably as a team when managing women with PPH (moderate confidence).

AUTHORS' CONCLUSIONS

Our findings highlight how improving PPH prevention, detection, and management is underpinned by a complex system of interacting roles and behaviours (community, women, health workers of different types and with different experiences). Multiple individual, sociocultural, and environmental factors influence the decisions and behaviours of women, families, communities, health workers, and managers. It is crucial to consider the broader health and social systems when designing and implementing PPH interventions to change or influence these behaviours. We have developed a set of prompts that may help programme managers, policymakers, researchers, and other key stakeholders to identify and address factors that affect implementation and scale-up of interventions to improve PPH prevention, detection, and management.

Carbetocin versus Oxytocin with or without Tranexamic Acid for Prophylactic Prevention of Postpartum Hemorrhage after a Vaginal Delivery: A Randomized Clinical Trial

OBJECTIVE

Our study's primary objective was to examine the effects of four different prophylactic protocols on the prevention of postpartum hemorrhage following vaginal birth, including carbetocin only, oxytocin only, and a combination of carbetocin or oxytocin with tranexamic acid.

DESIGN

A multicentric randomized controlled trial.

PARTICIPANTS/MATERIALS, SETTING, AND METHODS

This multicentric center prospective randomized controlled trial was conducted at the Department of Obstetrics and Gynecology of Bezmialem University and Van Health Teaching and Research Hospital from August 2022 to January 2023. The collected data included age, gravidity, parity, gestational age at birth, duration of delivery stages, prepartum hemoglobin and hematocrit concentrations, changes in hemoglobin and hematocrit concentrations, intrapartum blood loss, estimated blood loss after 2 h of vaginal delivery, Apgar scores at 1 and 5 min, birth weight, and neonatal intensive care unit (NICU) admission. Intrapartum blood loss was objectively measured in milliliters using a postpartum drape with a calibrated bag. The amount of bleeding was measured by subtracting the empty weight of the pads placed under the patient in the patient's bed within 2 h after delivery. Group I: carbetocin 100 μg/mL (n = 75), group II: oxytocin 5 IU/mL (n = 75), group III: carbetocin and tranexamic acid 50 mg/mL (n = 75), group IV: oxytocin and tranexamic acid (n = 75).

RESULTS

The hemoglobin concentration decrease significantly differed between groups (1.03 ± 1.04, 1.3 ± 0.85, 1.4 ± 0.85, 1.41 ± 0.87, respectively; p < 0.001). Group 4 has the highest decrease in hemoglobin and hematocrit concentrations. When we investigated the subgroup differences, the decrease in hemoglobin concentration was significantly higher in group 2 than group 1 (1.30 ± 0.85 vs. 1.03 ± 1.04; p = 0.023), in group 2 than group 3 (1.3 ± 0.85 vs. 1.04 ± 0.9; p = 0.013), and in group 4 than group 3 (1.41 ± 0.87 vs. 1.04 ± 0.9; p < 0.001). The decrease in hematocrit level was significantly different between groups (3.07 ± 3.23, 3.55 ± 2.44, 2.13 ± 3.09, 4.25 ± 2.52; p < 0.001, respectively). No significant differences were observed in terms of mean blood loss between the four groups (277.19 ± 208.10, 294.13 ± 198.64, 274.33 ± 199.57, and 283.97 ± 178.11; p = 0.445, respectively). Furthermore, there was no significant difference between the groups in the rate of need for blood transfusion (1.3%, 5.4%, 4%, and 4%, respectively; p = 0.6).

LIMITATIONS

The most important limitation of the study is a relatively small number of participants.

CONCLUSION

In conclusion, our findings suggest that carbetocin may be more successful than oxytocin and oxytocin plus tranexamic acid regimens in terms of postpartum hemoglobin reduction, and there is no difference in terms of the need for blood transfusion when it is used for postpartum hemorrhage prophylaxis after vaginal delivery.

Effectiveness of prophylactic carbetocin versus oxytocin following vaginal delivery for preventing severe postpartum hemorrhage

OBJECTIVE

To compare the effectiveness of prophylactic carbetocin with prophylactic oxytocin for preventing severe postpartum hemorrhage (PPH) following vaginal delivery.

METHODS

This before and after cohort study took place between 2020 and 2021 in a university maternity hospital. In 2021, the protocol for PPH prevention immediately after vaginal delivery changed: intravenous oxytocin (5 IU) was replaced by intravenous carbetocin (100 μg). All patients with vaginal births were included, with two groups compared: patients who received prophylactic oxytocin in 2020 and those who received prophylactic carbetocin in 2021. The primary outcome was severe PPH, defined as one or more of the following: estimated blood loss ≥1500 mL, transfusion ≥4 units of red blood cells, Bakri balloon use, embolization, vascular ligation, hysterectomy, and maternal death.

RESULTS

Among 4832 women included, 2417 received oxytocin and 2415 received carbetocin. The rate of severe PPH was similar in both groups (0.5% vs. 0.6%, respectively; adjusted odds ratio, 0.8 [95% confidence interval, 0.4-1.8]). The rate of PPH ≥500 mL was lower in the carbetocin group (4% vs. 5.8%; P = 0.004).

CONCLUSION

Although prophylactic carbetocin was associated with a reduction in the rate of PPH ≥500 mL, carbetocin is no different to oxytocin in preventing severe PPH caused by atony after vaginal delivery.

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.

Randomized Trial of Early Detection and Treatment of Postpartum Hemorrhage

BACKGROUND

Delays in the detection or treatment of postpartum hemorrhage can result in complications or death. A blood-collection drape can help provide objective, accurate, and early diagnosis of postpartum hemorrhage, and delayed or inconsistent use of effective interventions may be able to be addressed by a treatment bundle.

METHODS

We conducted an international, cluster-randomized trial to assess a multicomponent clinical intervention for postpartum hemorrhage in patients having vaginal delivery. The intervention included a calibrated blood-collection drape for early detection of postpartum hemorrhage and a bundle of first-response treatments (uterine massage, oxytocic drugs, tranexamic acid, intravenous fluids, examination, and escalation), supported by an implementation strategy (intervention group). Hospitals in the control group provided usual care. The primary outcome was a composite of severe postpartum hemorrhage (blood loss, ≥1000 ml), laparotomy for bleeding, or maternal death from bleeding. Key secondary implementation outcomes were the detection of postpartum hemorrhage and adherence to the treatment bundle.

RESULTS

A total of 80 secondary-level hospitals across Kenya, Nigeria, South Africa, and Tanzania, in which 210,132 patients underwent vaginal delivery, were randomly assigned to the intervention group or the usual-care group. Among hospitals and patients with data, a primary-outcome event occurred in 1.6% of the patients in the intervention group, as compared with 4.3% of those in the usual-care group (risk ratio, 0.40; 95% confidence interval [CI], 0.32 to 0.50; P<0.001). Postpartum hemorrhage was detected in 93.1% of the patients in the intervention group and in 51.1% of those in the usual-care group (rate ratio, 1.58; 95% CI, 1.41 to 1.76), and the treatment bundle was used in 91.2% and 19.4%, respectively (rate ratio, 4.94; 95% CI, 3.88 to 6.28).

CONCLUSIONS

Early detection of postpartum hemorrhage and use of bundled treatment led to a lower risk of the primary outcome, a composite of severe postpartum hemorrhage, laparotomy for bleeding, or death from bleeding, than usual care among patients having vaginal delivery. (Funded by the Bill and Melinda Gates Foundation; E-MOTIVE ClinicalTrials.gov number, NCT04341662.).

Cost-effectiveness and budget impact of heat-stable carbetocin compared to oxytocin and misoprostol for the prevention of postpartum hemorrhage (PPH) in women giving birth in India

INTRODUCTION

Low- and middle-income countries (LMICs) are committed to achieving the Sustainable Development Goal 3.1 to reduce maternal mortality. The Ministry of Health and Family Welfare of India recommends prophylactic uterotonic administration to every woman following delivery to reduce the risk of postpartum hemorrhage (PPH), as PPH is the leading cause of maternal mortality in LMICs, including India. In 2018, the World Health Organization first recognized heat-stable carbetocin for PPH prevention. Governments are now considering its introduction into their public health systems.

METHODS

A decision-tree model was developed from the public healthcare system perspective to compare the value of heat-stable carbetocin versus oxytocin and misoprostol among women giving birth in public sector healthcare facilities in India. The model accounted for differences in PPH risk and costs based on mode of delivery and healthcare setting, as well as provider behavior to mitigate quality concerns of oxytocin. Model outcomes for each prophylactic uterotonic included the number of PPH events, DALYs due to PPH, deaths due to PPH, and direct medical care costs. The budget impact was estimated based on projected uterotonic uptake between 2022-2026.

RESULTS

Compared to oxytocin, heat-stable carbetocin avoided 5,468 additional PPH events, 5 deaths, and 244 DALYs per 100,000 births. Projected direct medical costs to the public healthcare system were lowered by US $171,700 (₹12.8 million; exchange rate of ₹74.65 = US$1 from 2 Feb 2022) per 100,000 births. Benefits were even greater when compared to misoprostol (7,032 fewer PPH events, 10 fewer deaths, 470 fewer DALYs, and $230,248 saved per 100,000 births). In the budget impact analysis, India's public health system is projected to save US$11.4 million (₹849 million) over the next five years if the market share for heat-stable carbetocin grows to 19% of prophylactic uterotonics administered.

CONCLUSIONS

Heat-stable carbetocin is expected to reduce the number of PPH events and deaths, avoid more DALYs, and reduce costs to the public healthcare system of India. Greater adoption of heat-stable carbetocin for the prevention of PPH could advance India's efforts to achieve its maternal health goals and increase efficiency of its public health spending.

Maternal plasma cytokines and the subsequent risk of uterine atony and postpartum hemorrhage

OBJECTIVES

To determine whether the maternal plasma concentrations of cytokines are higher in pregnant women with postpartum hemorrhage (PPH) compared to pregnant women without PPH.

METHODS

A retrospective case-control study included 36 women with PPH and 72 matched controls. Cases and controls were matched for gestational age at delivery, labor status, delivery route, parity, and year of sample collection. Maternal plasma samples were collected up to 3 days prior to delivery. Comparison of the plasma concentrations of 29 cytokines was performed by using linear mixed-effects models and included adjustment for covariates and multiple testing. A false discovery rate adjusted p-value <0.1 was used to infer significance. Random forest models with evaluation by leave-one-out and 9-fold cross-validation were used to assess the combined value of the proteins in predicting PPH.

RESULTS

Concentrations of interleukin (IL)-16, IL-6, IL-12/IL-23p40, monocyte chemotactic protein 1 (MCP-1), and IL-1β were significantly higher in PPH than in the control group. This difference remained significant after adjustment for maternal age, clinical chorioamnionitis, and preeclampsia. Multi-protein random forest proteomics models had moderate cross-validated accuracy for prediction of PPH [area under the ROC curve, 0.69 (0.58-0.81) by leave-one-out cross validation and 0.73 (0.65-0.81) by 9-fold cross-validation], and the inclusion of clinical and demographic information did not increase the prediction performance.

CONCLUSIONS

Pregnant women with severe PPH had higher median maternal plasma concentrations of IL-16, IL-6, IL-12/IL-23p40, MCP-1, and IL-1β than patients without PPH. These cytokines could serve as biomarkers or their pathways may be therapeutic targets.

Investigation of metal modulation of oxytocin structure receptor-mediated signaling

Oxytocin is a 9-amino acid peptide hormone. Since its discovery in 1954, it has most commonly been studied in relation to its role in stimulating parturition and lactation. However, it is now known that oxytocin has a widely diverse set of functions throughout the body including neuromodulation, bone growth, and inflammation. Previous research has suggested that divalent metal ions may be required for oxytocin activity, but the exact metal species and specific pathways have yet to be fully elucidated. In this work, we focus on characterizing copper and zinc bound forms of oxytocin and related analogs through far-UV circular dichroism. We report that Cu(ii) and Zn(ii) bind uniquely to oxytocin and all analogs investigated. Furthermore, we investigate how these metal bound forms may affect downstream signaling of MAPK activation upon receptor binding. We find that both Cu(ii) and Zn(ii) bound oxytocin attenuates the activation of the MAPK pathway upon receptor binding relative to oxytocin alone. Interestingly, we observed that Zn(ii) bound forms of linear oxytocin facilitate increased MAPK signaling. This study lays the foundation for future work on elucidating the metal effects on oxytocin's diverse bioactivity.

Preventing postpartum hemorrhage with combined therapy rather than oxytocin alone

Postpartum hemorrhage is the leading cause of maternal morbidity and mortality worldwide, with uterine atony estimated to account for 70% to 80% of cases, thereby remaining the single most common cause. Pharmacotherapy remains the first-line preventative therapy for postpartum hemorrhage. These therapies may be single (oxytocin, carbetocin, methylergonovine, ergometrine, misoprostol, prostaglandin analogs, or tranexamic acid) or combination therapies, acting in an additive, infra-additive, or synergistic fashion to prevent postpartum hemorrhage. Evidence is strong for the use of oxytocin, the first-line uterotonic agent in the United States for prevention of postpartum hemorrhage. Although carbetocin, a long-acting analog of oxytocin, is not yet available for use in the United States, it is likely the most effective single pharmacologic therapy for prevention of postpartum hemorrhage and need for additional uterotonics. Use of second-line uterotonics such as methylergonovine, misoprostol, and carboprost in combination with oxytocin has an additive or synergistic effect and a greater risk reduction for postpartum hemorrhage prevention compared with oxytocin alone. Therefore, combined therapy rather than oxytocin alone should be advised for preventing postpartum hemorrhage. Tranexamic acid has been found to be both effective and safe for decreasing maternal mortality in women with postpartum hemorrhage, and prophylactic use of tranexamic acid may decrease the need for packed red blood cell transfusions and/or uterotonics. The WOMAN-2 Trial, designed to assess if tranexamic acid prevents postpartum hemorrhage in women with moderate to severe anemia undergoing vaginal delivery, is currently recruiting participants. The additive, infra-additive, or synergistic action of oxytocin in combination with other second-line therapies deserves further study.

Pharmacological Interventions in Labor and Delivery

While there is not a wide range of pregnancy-specific drugs, there are some very specific high-risk areas of obstetric care for which unique pharmacological approaches have been established. In preterm birth, labor induction and augmentation, and the management of postpartum hemorrhage, these pharmacological approaches have become the bedrock in managing some of the most common and problematic areas of antenatal and intrapartum care. In this review, we summarize the existing established and emerging evidence that supports and broadens these pharmacological approaches to obstetric management and its impact on clinical practice. It is clear that existing therapeutics are limited. They have largely been developed from our knowledge of the physiology of the myometrium and act on hormonal receptors and their signaling pathways or on ion channels influencing excitability. Newer drugs in development are mostly refinements of these two approaches, but novel agents from plants and improved formulations are also discussed.

Risk difference, relative risk, and odds ratio for non-inferiority clinical trials with risk rate endpoint

Non-inferiority (NI) clinical trials are widely used to evaluate whether the new experimental treatment is not unacceptably worse than the current active-control treatment by more than a pre-specified non-inferiority margin (NI margin). However, choosing either an absolute difference [risk difference (RD)] or a relative difference [relative risk (RR) and odds ratio (OR)] to evaluate efficacy in NI clinical trials is still controversial. In this study, we aim to evaluate the performance of abovementioned three metrics for testing NI clinical trials with risk rate endpoint. Herein, extensive Monte Carlo simulations based on various parameter settings (NI margin as well as risk rates in the experimental group and active-control group) are conducted to compare the Type I error rate, statistical power, and the necessary sample size to achieve a desired power for testing NI using RD, RR, and OR. We show that testing NI using RD not only controls well the Type I error and achieves the highest statistical power but also requires the smallest sample size compared to RR and OR. In practice, however, the choice among three metrics still needs to be based upon clinical interpretations and regulatory perspectives.

Comparison of Oxytocin vs. Carbetocin Uterotonic Activity after Caesarean Delivery Assessed by Electrohysterography: A Randomised Trial

Electrohysterography has been used for monitoring uterine contractility in pregnancy and labour. Effective uterine contractility is crucial for preventing postpartum haemorrhage. The objective of our study was to compare postpartum electrohysterograms in women receiving oxytocin vs. carbetocin for postpartum haemorrhage prevention after caesarean delivery. The trial is registered at ClinicalTrials.gov with the identifier NCT04201665. We included 64 healthy women with uncomplicated singleton pregnancies at term scheduled for caesarean section after one previous caesarean section. After surgery, a 15 min electrohysterogram was obtained after which women were randomised to receive either five IU of oxytocin intravenously or 100 μg of carbetocin intramuscularly. A 30 min electrohysterogram was performed two hours after drug application. Changes in power density spectrum peak frequency of electrohysterogram pseudo-bursts were analysed. A significant reduction in power density spectrum peak frequency in the first two hours was observed after carbetocin but not after oxytocin (median = 0.07 (interquartile range (IQR): 0.87 Hz) compared to median = -0.63 (IQR: 0.20) Hz; p = 0.004). Electrohysterography can be used for objective comparison of uterotonic effects. We found significantly higher power density spectrum peak frequency two hours after oxytocin compared to carbetocin.

Peripartum effects of synthetic oxytocin: The good, the bad, and the unknown

The first clinical applications of oxytocin (OT) were in obstetrics as a hormone to start and speed up labor and to control postpartum hemorrhage. Discoveries in the 1960s and 1970s revealed that the effects of OT are not limited to its peripheral actions around birth and milk ejection. Indeed, OT also acts as a neuromodulator in the brain affecting fear memory, social attachment, and other forms of social behaviors. The peripheral and central effects of OT have been separately subject to extensive scrutiny. However, the effects of peripheral OT-particularly in the form of administration of synthetic OT (synOT) around birth-on the central nervous system are surprisingly understudied. Here, we provide a narrative review of the current evidence, suggest putative mechanisms of synOT action, and provide new directions and hypotheses for future studies to bridge the gaps between neuroscience, obstetrics, and psychiatry.

Is there a role for carbetocin in the prophylaxis of postpartum obstetric haemorrhage?

Postpartum haemorrhage is a common complication of pregnancy, most commonly due to uterine atony. Uterotonics have a vital role in preventing postpartum haemorrhage but the choice of the most effective agent with the fewest adverse effects is a subject of debate. Carbetocin, a synthetic analogue of oxytocin has been available in the UK since 2007 but is not currently widely used. It has a longer duration of action than oxytocin, which avoids the need for an infusion and as it is heat-stable it can be stored at room temperature. Current UK clinical guidelines, based on the results of older meta-analyses, do not recommend carbetocin as a first-line agent. A Cochrane review, published in 2018, ranked carbetocin in the top three drug regimens for preventing postpartum haemorrhage and an international consensus statement on uterotonic use for caesarean birth concluded that carbetocin may become the preferred drug for caesarean birth, by reducing the need for additional uterotonics. The higher cost of carbetocin when compared with oxytocin is a limiting factor, but the significant healthcare costs of a postpartum haemorrhage and the physiological impact of this event suggests it a reasonable alternative to consider, especially if ergometrine is contraindicated or in those who are undergoing a caesarean birth or are at high risk of bleeding.

Effect of Carbetocin on Postpartum Hemorrhage after Vaginal Delivery: A Meta-Analysis

Background

The efficacy of oxytocin and carbetocin in preventing postpartum hemorrhage (PPH) in women with vaginal delivery has been controversial. This study is aimed at conducting a meta-analysis that compares the efficacy of carbetocin and oxytocin in the prevention of PPH among women with vaginal delivery.

Methods

Literature was retrieved from PubMed, Medline, Embase, CENTRAL, and CNKI databases. The randomized controlled trials (RCTs) that compare the efficacy of carbetocin and oxytocin to prevent PPH were searched. Data from the included literatures were extracted by two researchers, including author, title, publication date, study type, study number, the incidence of PPH, number of patients requiring additional uterotonics, and number of patients requiring blood transfusion. Jadad scale was used to evaluate the quality of the included RCTs. The Chi-square test was adopted for the heterogeneity test. A fixed-effect model was used for analysis if heterogeneity did not exist between literatures. If heterogeneity exists between literatures, a random-effect model was used for analysis. The source of heterogeneity was explored by subgroup analysis and sensitivity analysis.

Results

The incidence of PPH in the carbetocin group was lower than that in the oxytocin group (OR = 0.62, 95% CI (0.46, 0.84), Z = 3.14, P = 0.002). There was no heterogeneity among studies (χ² = 7.29, P = 0.12, I² = 45%) and no significant publication bias (P > 0.05). The proportion of women requiring additional uterotonics in the carbetocin group was lower than that in the oxytocin group (OR = 0.41, 95% CI (0.29, 0.56), Z = 5.34, P < 0.00001). There was no heterogeneity among studies (χ² = 0.82, P = 0.84, I² = 0%) and no significant publication bias (P > 0.05). There was no significant difference in the proportion of women needing blood transfusion between the carbetocin group and the oxytocin group (OR = 0.92, 95% CI (0.66, 1.29), Z = 0.46, P = 0.64). There was no heterogeneity among studies (χ² = 3.06, P = 0.55, I² = 0%) and no significant publication bias (P > 0.05).

Conclusion

Carbetocin is superior to oxytocin in preventing PPH among women with vaginal delivery and can be widely used in clinical practice.

A study protocol for the cardiac effects of a single dose of either oxytocin 2.5 IU or carbetocin 100 µg after caesarean delivery: a prospective randomized controlled multi-centre trial in Norway

Background: Both oxytocin and carbetocin are used to prevent uterine atony and post-partum haemorrhage after caesarean delivery in many countries, including Norway. Oxytocin causes dose-dependent ST-depression, troponin release, prolongation of QT-time and arrythmia, but little is known about myocardial effects of carbetocin. We have previously demonstrated comparable vasodilatory effects of oxytocin and carbetocin and are now undertaking a Phase 4 trial to investigate whether carbetocin causes similar changes to myocardial markers compared with oxytocin.

Methods: Our randomized controlled trial will be conducted at three obstetrics units at Oslo University Hospital and Akershus University Hospital, Norway. Planned enrolment will be of 240 healthy, singleton pregnant women aged 18 to 50 years undergoing planned caesarean delivery. Based on pilot study data, each participant will receive a one-minute intravenous injection of either oxytocin 2.5 IU or carbetocin 100 µg during caesarean delivery. The prespecified primary outcome is the change from baseline in high-sensitive troponin I plasma concentrations at 6–10 hours after study drug administration. Secondary outcomes include uterine tone grade at 2.5 and five minutes after study drug administration, adverse events for up to 48 hours after study drug administration, estimated blood loss within eight hours of delivery, need for rescue treatment and direct/indirect costs. Enrolment and primary analysis are expected to be completed by the end of 2021.

Discussion: Women undergoing caesarean delivery should be assessed for cardiovascular risk particularly as women with an obstetric history of pregnancy induced hypertension, gestational diabetes mellitus, preterm birth, placental abruption, and stillbirth are at increased risk of future cardiovascular disease. Any additional ischaemic myocardial risk from uterotonic agents will need to be balanced with the benefit of reducing the risk of postpartum haemorrhage. Any potential cardiotoxicity difference between oxytocin and carbetocin will help inform treatment decisions for pregnant women.

Registration: Clinicaltrials.gov NCT03899961 (02/04/2019).

Data flow within global clinical trials: a scoping review

Objective

To document clinical trial data flow in global clinical trials published in major journals between 2013 and 2021 from Global South to Global North.

Design

Scoping analysis

Methods

We performed a search in Cochrane Central Register of Controlled Trials (CENTRAL) to retrieve randomised clinical trials published between 2013 and 2021 from The BMJ, BMJ Global Health, the Journal of the American Medical Association, the Lancet, Lancet Global Health and the New England Journal of Medicine. Studies were included if they involved recruitment and author affiliation across different country income groupings using World Bank definitions. The direction of data flow was extracted with a data collection tool using sites of trial recruitment as the starting point and the location of authors conducting statistical analysis as the ending point.

Results

Of 1993 records initially retrieved, 517 studies underwent abstract screening, 348 studies underwent full-text screening and 305 studies were included. Funders from high-income countries were the sole funders of the majority (82%) of clinical trials that recruited across income groupings. In 224 (73.4%) of all assessable studies, data flowed exclusively to authors affiliated with high-income countries or to a majority of authors affiliated with high-income countries for statistical analysis. Only six (3.2%) studies demonstrated data flow to lower middle-income countries and upper middle-income countries for analysis, with only one with data flow to a lower middle-income country.

Conclusions

Global clinical trial data flow demonstrates a Global South to Global North trajectory. Policies should be re-examined to assess how data sharing across country income groupings can move towards a more equitable model.

Clinical algorithms for management of third stage abnormalities

AIMS

To develop algorithms for identifying, managing and monitoring postpartum haemorrhage (PPH) and other third stage of labour abnormalities after vaginal delivery.

POPULATION

Women with low-risk singleton term pregnancies who have had a vaginal delivery.

SETTING

Hospital settings with a particular focus on healthcare facilities in low- and middle-income countries (LMICs).

SEARCH STRATEGY

Searches for international and national guidance documents, research databases (Cochrane, Medline and CINAHL) and published systematic reviews. Searches were limited to work published in English between 1 January 2008 and 31 December 2018.

CASE SCENARIOS

Four interlinked case scenarios were identified for algorithm development: (1) an approach to PPH after vaginal delivery, (2) uterine atony, (3) genital tract trauma and (4) retained placenta/placental products.

CONCLUSIONS

The development of clear approaches to the assessment, resuscitation, treatment and monitoring of the four case scenarios are presented as algorithms, based on available evidence. They need to be field tested and evaluated for effectiveness, and may be adapted for electronic decision support tools using artificial intelligence in different settings. Further research is needed around multimodal sequential packages of care for PPH, conservative surgical measures, resuscitation in LMICs, and how a respectful maternity care focus can be incorporated into the algorithms.

TWEETABLE ABSTRACT

Algorithm development for standardised approaches to managing PPH in low-resource settings.

Implementing Heat-Stable Carbetocin for Postpartum Haemorrhage Prevention in Low-Resource Settings: A Rapid Scoping Review

Heat-stable carbetocin (HSC), a long-acting oxytocin analogue that does not require cold-chain transportation and storage, is effective in preventing postpartum haemorrhage (PPH) in vaginal and caesarean deliveries in tertiary-care settings. We aimed to identify literature documenting how it is implemented in resource-limited and lower-level maternity care settings to inform policies and practices that enable its introduction in these contexts. A rapid scoping review was conducted with an 8-week timeframe by two reviewers. MEDLINE, EMBASE, Emcare, the Joanna Briggs Institute Evidence-Based Practice Database, the Maternity and Infant Care Database, and the Cochrane Library were searched for publications in English, French, and Spanish from January 2011 to September 2021. Randomized and non-randomized studies examining the feasibility, acceptability, and health system considerations in low-income and lower-middle-income countries were included. Relevant data were extracted using pretested forms, and results were synthesized descriptively. The search identified 62 citations, of which 12 met the eligibility criteria. The review did not retrieve studies focusing on acceptability and health system considerations to inform HSC implementation in low-resource settings. There were no studies located in rural or lower-level maternity settings. Two economic evaluations concluded that HSC is not feasible in terms of cost-effectiveness in lower-middle-income economies with private sector pricing, and a third one found superior care costs in births with PPH than without. The other nine studies focused on demonstrating HSC effectiveness for PPH prevention in tertiary hospital settings. There is a lack of evidence on the feasibility (beyond cost-effectiveness), acceptability, and health system considerations related to implementing HSC in resource-constrained and lower-level maternity facilities. Further implementation research is needed to help decision-makers and practitioners offer an HSC-inclusive intervention package to prevent excessive bleeding among pregnant women living in settings where oxytocin is not available or of dubious quality.

Effectiveness and safety of carboxytocin versus oxytocin in preventing postpartum hemorrhage: A systematic review and meta-analysis

OBJECTIVE

This study compared the effectiveness and safety of carbetocin and oxytocin in preventing postpartum hemorrhage (PPH).

METHODS

A systematic literature search was performed on PubMed, Embase, and the Cochrane Library for relevant studies published up to February 2019. Next, two independent reviewers screened the studies according to the selection criteria as well as the strategies recommended by the Cochrane Collaboration. Data were then extracted and evaluated. All statistical analyses were performed using RevMan 5.1.

RESULTS

A total of 24 studies involving 37 383 patients were included for analysis. For cesarean section patients, carbetocin was superior to oxytocin in reduction of the need for additional uterine contraction (odds ratio [OR] = 0.48, 95% confidence interval [CI] [0.35, 0.65], p < 0.00001), PPH (OR = 0.70, 95% CI [0.51, 0.95], p = 0.02), blood loss (mean [MD] = -64.36, 95% CI [-107.78, -20.93], p = 0.004), and transfusion (OR = 0.59, 95% CI [0.42, 0.82], p = 0.002), and there was no significant difference in severe PPH (OR = 0.84, 95% CI [0.66, 1.090], p = 0.19). For vaginal delivery patients, carbetocin was superior to oxytocin in reduction of the need for additional uterine contractions (OR = 0.48, 95% CI [0.25, 0.93], p = 0.03), PPH (OR = 0.28, 95% CI [0.09, 0.91], p = 0.03), and blood loss (MD = -63.52, 95% CI [-113.43, -13.60], p = 0.01), and there were no significant differences in severe PPH (OR = 0.82, 95% CI [0.40, 1.69], p = 0.59) and transfusion (OR = 0.60, 95% CI [0.22, 1.61], p = 0.31). With regard to safety, for cesarean section patients, carbetocin was superior to oxytocin in reduction of the incidence of headache (OR = 0.72, [0.55, 0.95], p = 0.02), and there were no significant differences in nausea, vomiting, abdominal pain, flushing, tremors, itching, dizziness, and fever. For vaginal delivery patients, there were no significant differences in nausea, vomiting, headache, abdominal pain, flushing, tremors, itching, dizziness, and fever between the two drugs.

CONCLUSION

For patients undergoing cesarean section and vaginal delivery, carbetocin was superior to oxytocin in effectiveness and similar in safety. Therefore, carbetocin is expected to be an alternative uterine contraction agent for preventing PPH.

Heat stable carbetocin vs. oxytocin for the prevention of post-partum hemorrhage in emergency caesarean delivery: a randomized controlled trial

OBJECTIVES

To evaluate the uterotonic effect of carbetocin compared with oxytocin in emergency cesarean delivery in Iraq.

METHODS

A double-blinded randomized noninferiority single center trial. Three-hundred patients were systematically randomized to intravenous bolus injection of 10 IU oxytocin or 100 mcg carbetocin after delivery in a ratio of 2:1. The primary outcome was additional uterotonic use when inadequate uterine tone occur in the first 24 h after delivery. Secondary outcomes include the need for blood transfusion, blood pressure and pulse rate changes within an hour of drugs administration. Noninferiority margins for the relative risks outcomes was 4%.

RESULTS

Addition uterotonics use was significantly lower in carbetocin group with a risk ratio of 0.36. Carbetocin was superior to oxytocin in reducing the need for additional uterotonic drugs by 12% and non-inferior to oxytocin for blood transfusion 3.5%. Noninferiority was not shown for the outcome of sever blood loss. Miner changes in blood pressure and pulse rate were observed in carbetocin group compared to oxytocin but clinically were not significant.

CONCLUSIONS

Heat stable carbetocin is effective in reducing additional uterotonics use compared to oxytocin without clinically significant change in blood pressure or pulse rate, therefore, can be a potential alternative in Iraq.

Potential of a novel facultative anaerobic denitrifying Cupriavidus sp. W12 to remove fluoride and calcium through calcium bioprecipitation

This study focused on a novel denitrifying Cupriavidus sp. W12, which can perform microbial induced calcium precipitation (MICP) to remove fluoride (F^-) under aerobic and anaerobic conditions. Under anaerobic condition, the removal ratios of F^-, calcium (Ca²⁺), and nitrate (NO₃^--N) reached 87.52%, 65.03%, and 96.06%, respectively, which were higher than that under aerobic condition (50.17%, 88.21%, and 67.33%, respectively). Higher pH of 8.26 was obtained after 120 h of the strain W12 growth under anaerobic condition than that under aerobic condition (7.77). The F^- removal ratio of 98.20% was predicted by the response surface methodology (RSM). Scanning electron microscopy (SEM) images of anaerobic precipitation were dense and porous. CaCO₃, Ca₅(PO₄)₃OH, Ca₅(PO₄)₃F, and CaF₂ were determined by X-ray diffraction (XRD) and energy dispersive spectrometer (EDS). Self-aggregation of bacteria and adsorption of biological crystal seeds were the determinant of the precipitates formation. The results of infrared spectrometer (FTIR) and excitation-emission matrix (EEM) showed that anaerobic extracellular polymeric substances (EPS) expression led the proportion of hydroxylapatite in the precipitates increased. As the first report on the anaerobic MICP to remove F^-, it provides a theoretical basis for the remediation of F^-, Ca²⁺, and NO₃^--N in groundwater.

Cost-effectiveness analysis of carbetocin versus oxytocin for the prevention of postpartum hemorrhage following vaginal birth in the United Kingdom

AIMS

To assess the cost-effectiveness of carbetocin versus oxytocin for the prevention of postpartum hemorrhage (PPH) following vaginal birth from the perspective of the UK National Health Service (NHS).

MATERIALS AND METHODS

A decision tree model was designed to analyze the cost per PPH event avoided associated with utilizing carbetocin versus oxytocin for prophylactic treatment of PPH in women following vaginal birth from a UK perspective. It modelled the potential for women to require an additional uterotonic after prophylaxis, and to still experience a PPH event and receive associated treatment. Inpatient recovery and follow-up periods post-PPH were also included in the model. Costs associated with drug acquisition and administration, PPH management (i.e. additional staffing and possible operating theater and high dependency unit utilization), inpatient hospitalization, and follow-up visits were all considered. Adverse event management costs were not included. Resource utilization varied depending on the severity of the PPH event (as defined by the amount of blood lost). PPH events avoided were estimated. In an exploratory analysis, quality adjusted life years (QALYs) were estimated as well.

RESULTS

In the deterministic base case, costs were £55 lower and PPH events were 0.0342 lower per woman with carbetocin use compared to oxytocin use. Across the cohort of 100 women the reduction in PPH events led to the largest cost savings (£4,233 saved) out of all cost categories, with total cost savings of £5,495. Carbetocin utilization amongst the entire cohort led to 3.42 avoided PPH events compared to oxytocin utilization, comprised of 3.03 fewer mild/moderate PPH events and 0.39 fewer severe PPH events. Carbetocin utilization led to 0.0001 additional QALYs per woman.

CONCLUSION

Carbetocin utilization leads to lower prophylactic treatment costs and less PPH events versus oxytocin when utilized for the prevention of PPH following vaginal birth in the UK.

The Current Status of Drug Discovery for the Oxytocin Receptor

The oxytocin receptor plays a significant role in peripheral regulation of parturition and lactation. Given this important role, multiple drug discovery programs have been conducted to develop agonists and antagonists for peripheral activity. The role of the oxytocin receptor in the central nervous system is also significant, promoting social interaction, trust, and empathy in humans. As such, molecules that can access the central nervous system and target the oxytocin receptor are of significant interest. Due to the role of the oxytocin receptor in regulating social function and psychological well-being, agonists of this receptor have considerable promise for the treatment of numerous neuropsychiatric conditions. The poor pharmacokinetic properties and blood-brain barrier penetration of peptide-based molecules means nonpeptide compounds have more commonly been the focus for central nervous system activity. This chapter aims to summarize the current standing of peptide and nonpeptide drug discovery for antagonists and agonists of the oxytocin receptor and focusses on centrally active nonpeptidic agonists.

Obstetrical Hemorrhage

Obstetric hemorrhage is a leading cause of morbidity and mortality. Prevention includes identifying patients with risk factors and actively managing the third stage of labor. The anesthesiologist should be ready to manage hemorrhage with general strategies as well as strategies tailored to the specific cause of hemorrhage. Both neuraxial anesthesia and general anesthesia are appropriate in different situations. Treatments proven to be effective include increasing the oxytocin infusion, administering tranexamic acid early, guiding transfusion with point-of-care tests, and using cell salvage. Utilization of protocols and checklists within systems that encourage effective communication between teams should be implemented.

Duration of third stage labour and postpartum blood loss: a secondary analysis of the WHO CHAMPION trial data

Background

Obstetric haemorrhage continues to be a leading cause of maternal mortality, contributing to more than a quarter of the 2,443,000 maternal deaths reported between 2003 and 2009. During this period, about 70% of the haemorrhagic deaths occurred postpartum. In addition to other identifiable risk factors for greater postpartum blood loss, the duration of the third stage of labour (TSL) seems to be important, as literature shows that a longer TSL can be associated with more blood loss. To better describe the association between the duration of TSL and postpartum blood loss in women receiving active management of third stage of labour (AMTSL), this secondary analysis of the WHO CHAMPION trial data has been conducted.

Methods

This was a secondary analysis of the WHO CHAMPION trial conducted in twenty-three sites in ten countries. We studied the association between the TSL duration and blood loss in the sub cohort of women from the CHAMPION trial (all of whom received AMTSL), with TSL upto 60 min and no interventions for postpartum haemorrhage. We used a general linear model to fit blood loss as a function of TSL duration on the log scale, arm and center, using a normal distribution and the log link function. We showed this association separately for oxytocin and for Heat stable (HS) carbetocin.

Results

For the 10,040 women analysed, blood loss rose steeply with third stage duration in the first 10 min, but more slowly after 10 min. This trend was observed for both Oxytocin and HS carbetocin and the difference in the trends for both drugs was not statistically significant (p-value = 0.2070).

Conclusions

There was a positive association between postpartum blood loss and TSL duration with either uterotonic. Blood loss rose steeply with TSL duration until 10 min, and more slowly after 10 min.

Study registration The main trial was registered with Australian New Zealand Clinical Trials Registry ACTRN12614000870651 and Clinical Trial Registry of India CTRI/2016/05/006969

The duration of the third stage of labour (TSL) seems to be an important risk factor for greater postpartum blood loss, as literature shows that a longer TSL can be associated with more blood loss. Active management of third stage of labour (AMTSL), included in the WHO guidelines for prevention of postpartum haemorrhage (PPH), is effective in reducing both the amount of postpartum blood loss and the duration of the third stage. To better describe the association between duration of TSL and postpartum blood loss in women receiving AMTSL, we conducted this secondary analysis of WHO CHAMPION trial data.

To assess the association between the duration of third stage of labour and postpartum blood loss, a subcohort of the CHAMPION modified ITT population was selected by excluding women with missing blood loss or missing TSL duration or TSL duration more than 60 min and women with interventions. Thus, the subcohort consisted of 10,040 women.

In women with vaginal birth and not receiving interventions for treating atonic PPH or other sources of bleeding, and with TSL duration up to 60 min, there was a positive association between duration of the TSL and postpartum blood loss. The blood loss rose steeply with duration in women with TSL of 10 min or less, while in women with longer TSL duration the slope was less steep.

There was no evidence of a difference between oxytocin and HS carbetocin in the pattern of association of duration of the TSL and blood loss.

A study protocol for the cardiac effects of a single dose of either oxytocin 2.5 IU or carbetocin 100 µg after caesarean delivery: a prospective randomized controlled multi-centre trial in Norway

Background: Both oxytocin and carbetocin are used to prevent uterine atony and post-partum haemorrhage after caesarean delivery in many countries, including Norway. Oxytocin causes dose-dependent ST-depression, troponin release, prolongation of QT-time and arrythmia, but little is known about myocardial effects of carbetocin. We have previously demonstrated comparable vasodilatory effects of oxytocin and carbetocin and are now undertaking a Phase 4 trial to investigate whether carbetocin causes similar changes to myocardial markers compared with oxytocin. Methods: Our randomized controlled trial will be conducted at three obstetrics units at Oslo University Hospital and Akershus University Hospital, Norway. Planned enrolment will be of 240 healthy, singleton pregnant women aged 18 to 50 years undergoing planned caesarean delivery. Based on pilot study data, each participant will receive a one-minute intravenous injection of either oxytocin 2.5 IU or carbetocin 100 µg during caesarean delivery. The prespecified primary outcome is the change from baseline in high-sensitive troponin I plasma concentrations at 6-10 hours after study drug administration. Secondary outcomes include uterine tone grade at 2.5 and five minutes after study drug administration, adverse events for up to 48 hours after study drug administration, estimated blood loss within eight hours of delivery, need for rescue treatment and direct/indirect costs. Enrolment and primary analysis are expected to be completed by the end of 2021. Discussion: Women undergoing caesarean delivery should be assessed for cardiovascular risk particularly as women with an obstetric history of pregnancy induced hypertension, gestational diabetes mellitus, preterm birth, placental abruption, and stillbirth are at increased risk of future cardiovascular disease. Any additional ischaemic myocardial risk from uterotonic agents will need to be balanced with the benefit of reducing the risk of postpartum haemorrhage. Any potential cardiotoxicity difference between oxytocin and carbetocin will help inform treatment decisions for pregnant women. Registration: Clinicaltrials.gov NCT03899961 (02/04/2019).

Oxytocin: A citation network analysis of 10 000 papers

Our understanding of the oxytocin system has been built over the last 70 years by the work of hundreds of scientists, reported in thousands of papers. Here, we construct a map to that literature, using citation network analysis in conjunction with bibliometrics. The map identifies ten major 'clusters' of papers on oxytocin that differ in their particular research focus and that densely cite papers from the same cluster. We identify highly cited papers within each cluster and in each decade, not because citations are a good indicator of quality, but as a guide to recognising what questions were of wide interest at particular times. The clusters differ in their temporal profiles and bibliometric features; here, we attempt to understand the origins of these differences.

Carbetocin versus oxytocin following vaginal and Cesarean delivery: a before-after study

PURPOSE

A nationwide shortage of oxytocin in Canada resulted in a temporary switch from oxytocin to carbetocin for all postpartum women at our institution. This change offered a unique opportunity to conduct a pragmatic comparative assessment of the efficacy of carbetocin and oxytocin.

METHODS

In a retrospective before-after study, we reviewed the medical records from 641 women in the carbetocin group and 752 women in the oxytocin group . The standard carbetocin dosing was 100 µg iv following vaginal and intrapartum Cesarean delivery, while for elective Cesarean delivery it was 50 µg, with an additional 50 µg if required. The standard oxytocin dosing was 5 IU iv followed by 2.4 IU·hr^-1 for four to six hours after vaginal delivery, while for Cesarean delivery it was 1-3 IU iv, three minutes apart, up to 10 IU if required, followed by the same maintenance. In both modalities of delivery, if uterine tone was suboptimal, the maintenance dose of oxytocin could be increased to 4.8 IU·hr^-1. In both groups, additional uterotonics were used as required. The primary outcome was the need for additional uterotonics. Secondary outcomes included estimated and calculated blood loss, the occurrence of postpartum hemorrhage, and the need for blood transfusion.

RESULTS

The incidence of additional uterotonic use was not different between the carbetocin and oxytocin groups (12.0% vs 8.8%; P = 0.05; odds ratio, 1.39; 95% confidence interval, 0.97 to 2.00). The incidence of postpartum hemorrhage was higher in the carbetocin group than in the oxytocin group (10.3% vs 6.6%; P = 0.01). Blood transfusion was more common in the carbetocin group (1.4% vs 0.3%; P = 0.02).

CONCLUSION

There was no difference in the use of additional uterotonics when carbetocin or oxytocin were used in a cohort of women undergoing vaginal deliveries and both elective and emergency Cesarean deliveries.

Choosing and changing the analysis scale in non-inferiority trials with a binary outcome

Background

The size of the margin strongly influences the required sample size in non-inferiority and equivalence trials. What is sometimes ignored, however, is that for trials with binary outcomes, the scale of the margin – risk difference, risk ratio or odds ratio – also has a large impact on power and thus on sample size requirement. When considering several scales at the design stage of a trial, these sample size consequences should be taken into account. Sometimes, changing the scale may be needed at a later stage of a trial, for example, when the event proportion in the control arm turns out different from expected. Also after completion of a trial, a switch to another scale is sometimes made, for example, when using a regression model in a secondary analysis or when combining study results in a meta-analysis that requires unifying scales. The exact consequences of such switches are currently unknown.

Methods and Results

This article first outlines sample size consequences for different choices of analysis scale at the design stage of a trial. We add a new result on sample size requirement comparing the risk difference scale with the risk ratio scale. Then, we study two different approaches to changing the analysis scale after the trial has commenced: (1) mapping the original non-inferiority margin using the event proportion in the control arm that was anticipated at the design stage or (2) mapping the original non-inferiority margin using the observed event proportion in the control arm. We use simulations to illustrate consequences on type I and type II error rates. Methods are illustrated on the INES trial, a non-inferiority trial that compared single birth rates in subfertile couples after different fertility treatments. Our results demonstrate large differences in required sample size when choosing between risk difference, risk ratio and odds ratio scales at the design stage of non-inferiority trials. In some cases, the sample size requirement is twice as large on one scale compared with another. Changing the scale after commencing the trial using anticipated proportions mainly impacts type II error rate, whereas switching using observed proportions is not advised due to not maintaining type I error rate. Differences were more pronounced with larger margins.

Conclusions

Trialists should be aware that the analysis scale can have large impact on type I and type II error rates in non-inferiority trials.

Clearance of oxytocin and its potentially enzyme resistant analogues in the OXT-receptor compartment of the potassium depolarized rat myometrium

The time–response behaviour of a group of oxytocin analogues structurally modified on potential sites of oxytocin splitting by tissue inactivation enzymes (“enzyme probes”) was investigated ex vivo on the potassium depolarized rat myometrium (at 30°C) and compared with the data obtained in the in vivo experiments. The modified oil‐immersion method by Kalsner and Nickerson was used to record time profiles after cessation of a steady state myometrium contraction triggered by analogues in a high potassium tissue medium. An exchange of the aqueous medium for mineral oil enables to suppress return diffusion of the peptide and to record its irreversible clearance near the corresponding receptor compartment. Response records were analysed by a nonlinear numeric procedure based on combination of steady state and kinetic terms that allows concomitant estimations of affinities from time–response measurements, in the given case for analogues on depolarized myometrium. Potential inactivation‐sensitive sites in the oxytocin chain are the Ν‐terminal peptide bond Cys¹‐Tyr² (aminopeptidase splitting), the intramolecular disulphide bridge (reduction and formation of the practically inactive linear peptide) and the C‐terminal Leu⁸‐GlyNH₂⁹ or the Pro⁷‐Leu⁸ (postprolin cleaving enzyme) bond, respectively. Clearance rate constants of single peptides in the OXT‐receptor compartment were in an interval of 0.025 to 0.28 min⁻¹. The fragment contribution analysis reveals a significant linear additivity of individual structural changes and thus a predictivity of irreversible inactivation rate in the receptor compartment. The most potent inactivation of oxytocin is associated with aminopeptidase splitting; other enzymes may play some though nondecisive role. Less significant differences within the peptide group were found for rate constants for peptide transport between receptor compartment and its external aqueous medium. Besides rate constants, the evaluation of time–response data yields affinity values of the tested peptides and indicates a 25‐times desensitation of depolarized compared with a native state.

Number and quality of randomized controlled trials in obstetrics published in the top general medical and obstetrics and gynecology journals

BACKGROUND

There has been an increasing number of randomized controlled trials published in obstetrics and maternal-fetal medicine to reduce biases of treatment effect and to provide insights on the cause-effect of the relationship between treatment and outcomes.

OBJECTIVE

This study aimed to identify obstetrical randomized controlled trials published in top weekly general medical journals and monthly obstetrics and gynecology journals, to assess their quality in reporting and identify factors associated with publication in different journals.

STUDY DESIGN

The 4 weekly medical journals with the highest 2019 impact factor (New England Journal of Medicine, The Lancet, The Journal of the American Medical Association, and British Medical Journal), the top 4 monthly obstetrics and gynecology journals with obstetrics-related research (American Journal of Obstetrics & Gynecology, Ultrasound in Obstetrics & Gynecology, Obstetrics & Gynecology, and the British Journal of Obstetrics and Gynaecology), and the American Journal of Obstetrics & Gynecology Maternal-Fetal Medicine were searched for obstetrical randomized controlled trials in the years 2018 to 2020. The primary outcome was the number of obstetrical randomized controlled trials published in the obstetrics and gynecology journals vs the weekly medical journals and the percentage of trials published, overall and per journal. The secondary outcomes included the proportion of positive vs negative trials overall and per journal and the assessment of the study characteristics of published trials, including quality assessment criteria.

RESULTS

Of the 4024 original research articles published in the 9 journals during the 3-year study period, 1221 (30.3%) were randomized controlled trials, with 137 (11.2%) randomized controlled trials being in obstetrics (46 in 2018, 47 in 2019, and 44 studies in 2020). Furthermore, 33 (24.1%) were published in weekly medical journals, and 104 (75.9%) were published in obstetrics and gynecology journals. The percentage of obstetrical randomized controlled trials published ranged from 1.5% to 9.6% per journal. Overall, 34.3% of obstetrical trials were statistically significant or "positive" for the primary outcome. Notably, 24.8% of the trials were retrospectively registered after the enrollment of the first study patient. Trials published in the 4 weekly medical journals enrolled significantly more patients (1801 vs 180; P<.001), received more often funding from the federal government (78.8% vs 35.6%; P<.001), and were more likely to be multicenter (90.9% vs 42.3%; P<.001), non-United States based (69.7% vs 49.0%; P=.03), and double blinded (45.5% vs 18.3%; P=.003) than trials published in the obstetrics and gynecology journals. There was no difference in study type (noninferiority vs superiority) and trial quality characteristics, including pretrial registration, ethics approval statement, informed consent statement, and adherence to the Consolidated Standards of Reporting Trials guidelines statement between studies published in weekly medical journals and studies published in obstetrics and gynecology journals.

CONCLUSION

Approximately 45 trials in obstetrics are being published every year in the highest impact journals, with one-fourth being in the weekly medical journals and the remainder in the obstetrics and gynecology journals. Only about a third of published obstetrical trials are positive. Trials published in weekly medical journals are larger, more likely to be funded by the government, multicenter, international, and double blinded. Quality metrics are similar between weekly medical journals and obstetrics and gynecology journals.

Cost Implications of Using Carbetocin Injection to Prevent Postpartum Hemorrhage in a Canadian Urban Hospital

OBJECTIVE

Recent World Health Organization (WHO) recommendations regarding uterotonics for the prevention of postpartum hemorrhage (PPH) state that carbetocin should be considered a first-line prophylactic agent for all births where its cost is comparable to other effective uterotonics. This study evaluated whether a room temperature stable formulation of carbetocin met this recommendation in a Canadian urban hospital setting.

METHODS

A decision tree model was developed to assess the financial implications of replacing oxytocin with carbetocin as a first-line prophylactic agent for PPH prevention in a Greater Toronto Area (GTA) hospital. The analysis accounted for the mode of delivery, efficacies of carbetocin and oxytocin in PPH prevention, occurrence of PPH-related health outcomes, and health care resource costs for PPH interventions.

RESULTS

This study found that a GTA hospital, with 3242 deliveries per year, could save over CAD $349 000 annually by switching to room temperature stable carbetocin for PPH prevention. Carbetocin was able to lower institution costs by reducing the use of health care resources for PPH management in low-risk and high-risk PPH patients. The cost-saving potential of carbetocin relative to oxytocin was largely attributed to its greater efficacy in preventing the consequences of PPH.

CONCLUSION

The use of room temperature stable carbetocin as a first-line prophylactic agent for PPH prevention meets WHO recommendations regarding uterotonics for PPH in a GTA hospital. The model from this study can be used to determine the financial impact of switching from oxytocin to carbetocin in other jurisdictions while diversifying a hospital's pool of PPH prophylactic agents.

Relationship between anaemia, coagulation parameters during pregnancy and postpartum haemorrhage at childbirth: a prospective cohort study

OBJECTIVES

To investigate the association between coagulation parameters and severity of anaemia (moderate anaemia: haemoglobin (Hb) 7-9.9 g/dL and severe anaemia: Hb <7 g/dL) during pregnancy and relate these to postpartum haemorrhage (PPH) at childbirth.

DESIGN

A prospective cohort study of pregnant women recruited in the third trimester and followed-up after childbirth.

SETTING

Ten hospitals across four states in India.

PARTICIPANTS

1342 pregnant women.

INTERVENTION

Not applicable.

METHODS

Hb and coagulation parameters: fibrinogen, D-dimer, D-dimer/fibrinogen ratio, platelets and international normalised ratio (INR) were measured at baseline. Participants were followed-up to measure blood loss within 2 hours after childbirth and PPH was defined based on blood loss and clinical assessment. Associations between coagulation parameters, Hb, anaemia and PPH were examined using multivariable logistic regression models.

OUTCOMES MEASURES

Adjusted OR with 95% CI.

RESULTS

In women with severe anaemia during the third trimester, the D-dimer was 27% higher, mean fibrinogen 117 mg/dL lower, D-dimer/fibrinogen ratio 69% higher and INR 12% higher compared with women with no/mild anaemia. Mean platelets in severe anaemia was 37.8×109/L lower compared with women with moderate anaemia. Similar relationships with smaller effect sizes were identified for women with moderate anaemia compared with women with no/mild anaemia. Low Hb and high INR at third trimester of pregnancy independently increased the odds of PPH at childbirth, but the other coagulation parameters were not found to be significantly associated with PPH.

CONCLUSION

Altered blood coagulation profile in pregnant women with severe anaemia could be a risk factor for PPH and requires further evaluation.

Development of a thermostable oxytocin microneedle patch

Oxytocin is a nonapeptide hormone used in labor to initiate uterine contractions and to prevent and treat postpartum hemorrhage. Oxytocin is currently administered by injection and requires refrigerated transport and storage, which limits access, especially during home birth in developing countries. Here, we propose a thermostable, simple-to-administer microneedle (MN) patch for rapid delivery of oxytocin suitable for use by healthcare workers with limited training, like traditional birth attendants. Oxytocin (10 IU, 16.8 μg) coated onto stainless steel MN arrays was released into skin within 1-5 min after manual insertion. Among tested excipients, polyacrylic acid was best at stabilizing oxytocin stored at 75% relative humidity, with no significant loss for up to 2 months at 40 °C. Under desiccated conditions, MNs coated with formulations containing trehalose in a mixture of citrate buffer and ethanol retained 75% oxytocin potency at 40 °C for 12 months; the commercial oxytocin product Pitocin® was reduced to 35% potency under these conditions. These findings support development of MN patches for oxytocin administration with improved ease of use, extended thermostability and simplified logistics to enable greater access to this life-saving medicine.

Carbetocin for the prevention of post-partum hemorrhage after vaginal birth: a real-world application

OBJECTIVE

To compare maternal outcomes using Carbetocin versus Oxytocin for the active management of the third stage of labor, given a temporary national shortage of Oxytocin.

METHODS

We conducted a retrospective observational study on a cohort of 866 women with vaginal deliveries at our center, >36 weeks of gestation, between November 2018 and March 2019. During the shortage period, each woman received a single slow intravenous injection of Carbetocin 100 µg at delivery of the anterior shoulder, rather than Oxytocin 5 UI, as postpartum hemorrhage prophylaxis. 146 (16.9%) patients received Carbetocin versus 720 (83.1%) receiving Oxytocin. The outcomes were rates of postpartum hemorrhage, severe postpartum hemorrhage, and placental retention.

RESULTS

Incidence rates of placental retention and postpartum hemorrhage were 4.9% and 9.4% respectively. Placenta retention was significantly more likely following Carbetocin administration (adjusted odds ratio 2.5; 95% confidence interval 1.2-5.0). Postpartum hemorrhage rates were not significantly different (adjusted odds ratio 1.1; 95% confidence interval 0.6-2.1), as were severe postpartum hemorrhage rates (adjusted odds ratio 0.7; 95% confidence interval 0.2-2.2).

CONCLUSION

Carbetocin is as effective as Oxytocin for postpartum hemorrhage prevention. However, we would reserve it for use after placental delivery due to the increased retention rates.

Refractory uterine atony: still a problem after all these years

Postpartum hemorrhage is a leading cause of maternal morbidity and mortality, and uterine atony is the leading cause of postpartum hemorrhage. Risk factors for uterine atony include induced or augmented labor, preeclampsia, chorio-amnionitis, obesity, multiple gestation, polyhydramnios, and prolonged second stage of labor. Although a risk assessment is recommended for all parturients, many women with uterine atony do not have risk factors, making uterine atony difficult to predict. Oxytocin is the first-line drug for prevention and treatment of uterine atony. It is a routine component of the active management of the third stage of labor. An oxytocin bolus dose as low as 1 IU is sufficient to produce satisfactory uterine tone in almost all women undergoing elective cesarean delivery. However, a higher bolus dose (3 IU) or infusion rate is recommended for women undergoing intrapartum cesarean delivery. Carbetocin, available in many countries, is a synthetic oxytocin analog with a longer duration than oxytocin that allows bolus administration without an infusion. Second line uterotonic agents include ergot alkaloids (ergometrine and methylergonovine) and the prostaglandins, carboprost and misoprostol. These drugs work by a different mechanism to oxytocin and should be administered early for uterine atony refractory to oxytocin. Rigorous studies are lacking, but methylergonovine and carboprost are likely superior to misoprostol. Currently, the choice of second-line agent should be based on their adverse effect profile and patient comorbidities. Surgical and radiologic management of uterine atony includes uterine tamponade using balloon catheters and compression sutures, and percutaneous transcatheter arterial embolization.

Formative research to design an implementation strategy for a postpartum hemorrhage initial response treatment bundle (E-MOTIVE): study protocol

BACKGROUND

Postpartum hemorrhage (PPH) is the leading cause of maternal death worldwide. When PPH occurs, early identification of bleeding and prompt management using evidence-based guidelines, can avert most PPH-related severe morbidities and deaths. However, adherence to the World Health Organization recommended practices remains a critical challenge. A potential solution to inefficient and inconsistent implementation of evidence-based practices is the application of a 'clinical care bundle' for PPH management. A clinical care bundle is a set of discrete, evidence-based interventions, administered concurrently, or in rapid succession, to every eligible person, along with teamwork, communication, and cooperation. Once triggered, all bundle components must be delivered. The E-MOTIVE project aims to improve the detection and first response management of PPH through the implementation of the "E-MOTIVE" bundle, which consists of (1) Early PPH detection using a calibrated drape, (2) uterine Massage, (3) Oxytocic drugs, (4) Tranexamic acid, (5) Intra Venous fluids, and (6) genital tract Examination and escalation when necessary. The objective of this paper is to describe the protocol for the formative phase of the E-MOTIVE project, which aims to design an implementation strategy to support the uptake of this bundle into practice.

METHODS

We will use behavior change and implementation science frameworks [e.g. capability, opportunity, motivation and behavior (COM-B) and theoretical domains framework (TDF)] to guide data collection and analysis, in Kenya, Nigeria, South Africa, Sri Lanka, and Tanzania. There are four methodological components: qualitative interviews; surveys; systematic reviews; and design workshops. We will triangulate findings across data sources, participant groups, and countries to explore factors influencing current PPH detection and management, and potentially influencing E-MOTIVE bundle implementation. We will use these findings to develop potential strategies to improve implementation, which will be discussed and agreed with key stakeholders from each country in intervention design workshops.

DISCUSSION

This formative protocol outlines our strategy for the systematic development of the E-MOTIVE implementation strategy. This focus on implementation considers what it would take to support roll-out and implementation of the E-MOTIVE bundle. Our approach therefore aims to maximize internal validity in the trial alongside future scalability, and implementation of the E-MOTIVE bundle in routine practice, if proven to be effective.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT04341662.