Prevention of postpartum haemorrhage with the oxytocin analogue carbetocin

Oxytocin Analogues for the Oral Treatment of Abdominal Pain

Abdominal pain presents an onerous reality for millions of people affected by gastrointestinal disorders such as irritable bowel syndrome (IBS) and inflammatory bowel diseases (IBD). The oxytocin receptor (OTR) has emerged as a new analgesic drug target with OTR expression upregulated on colon-innervating nociceptors in chronic visceral hypersensitivity states, accessible via luminal delivery. However, the low gastrointestinal stability of OTR's endogenous peptide ligand oxytocin (OT) is a bottleneck for therapeutic development. Here, we report the development of potent and fully gut-stable OT analogues, laying the foundation for a new area of oral gut-specific peptide therapeutics. Ligand optimisation guided by structure-gut-stability-activity relationships yielded highly stable analogues (t1/2>24 h, compared to t1/2<10 min of OT in intestinal fluid) equipotent to OT (~3 nM) and with enhanced OTR selectivity. Intra-colonic administration of the lead ligand significantly reduced colonic mechanical hypersensitivity in a concentration-dependent manner in a mouse model of chronic abdominal pain. Moreover, oral administration of the lead ligand also displayed significant analgesia in this abdominal pain mouse model. The generated ligands and employed strategies could pave the way to a new class of oral gut-specific peptides to study and combat chronic gastrointestinal disorders, an area with substantial unmet medical needs.

Carbetocin versus oxytocin for the prevention of postpartum haemorrhage during caesarean section in patients at high risk of bleeding

OBJECTIVE

To evaluate the efficacy of carbetocin versus oxytocin in preventing postpartum haemorrhage (PPH) in women with risk factors for PPH who were delived by caesarean section.

METHODS

This retrospective, monocentric, before-and-after cohort study assessed patients with haemorrhagic risk factors who underwent caesarean section after 24 weeks of gestation and who had haemorrhagic risk factors between August 2014 to December 2019.

RESULTS

This study enrolled 518 patients, including 250 in the oxytocin group and 268 in the carbetocin group. The use of carbetocin was independently associated with a PPH decrease compared to oxytocin use (adjusted odds ratio [OR]: 0.52; 95 % confidence interval [CI]: 0.35-0.79; p = 0.002). Carbetocin use was associated with a reduction in the need for therapy escalation (6 % vs 10.8 %; p = 0.046).

CONCLUSION

Carbetocin was more effective than oxytocin in preventing PPH after caesarean section in high-risk patients.

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.

Peripartum Maternal Admission to the Intensive Care Unit: An Observational Study over a 15-Year Period at a Tertiary Center in Austria

Peripartum maternal admission to the intensive care unit is challenging for anesthesiologists, obstetricians, and all personnel involved. An understanding of altered maternal physiology, fetal considerations, and acute peripartum emergencies is required to ensure adequate maternal and neonatal outcomes. In this study, we analyzed data of peripartum maternal admissions to the intensive care unit at our large tertiary referral center in order to define trends and changes over time. This study retrospectively analyzed maternal morbidity, admission diagnoses, treatments, and outcomes of women with peripartum admission to the intensive care unit at our tertiary care center over a 15-year period. We found that patient characteristics and admission diagnoses remained remarkably consistent over the observational period; however, there was a significant increase in postpartum hemorrhage (r = 0.200, p < 0.001) and cesarean hysterectomy (r = 0.117, p = 0.027) over time. Moreover, we found a reduction in preterm births (r = -0.154, p = 0.004) and a decreased peripartum neonatal intensive care unit admission rate (r = -0.153, p = 0.006) among women who were transferred to the intensive care unit. Based on our long-term observational data, there is consistent need for intensive care in obstetrics due to a small number of different etiologies. Specialized training for the predominant diagnoses involved as well as multidisciplinary care of the affected patients are both warranted.

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.

Two oxytocin analogs, N-(p-fluorobenzyl) glycine and N-(3-hydroxypropyl) glycine, induce uterine contractions ex vivo in ways that differ from that of oxytocin

Contraction of the uterus is critical for parturient processes. Insufficient uterine tone, resulting in atony, can potentiate postpartum hemorrhage; thus, it is a major risk factor and is the main cause of maternity-related deaths worldwide. Oxytocin (OT) is recommended for use in combination with other uterotonics for cases of refractory uterine atony. However, as the effect of OT dose on uterine contraction and control of blood loss during cesarean delivery for labor arrest are highly associated with side effects, small amounts of uterotonics may be used to elicit rapid and superior uterine contraction. We have previously synthesized OT analogs 2 and 5, prolines at the 7th positions of which were replaced with N-(p-fluorobenzyl) glycine [thus, compound 2 is now called fluorobenzyl (FBOT)] or N-(3-hydroxypropyl) glycine [compound 5 is now called hydroxypropyl (HPOT)], which exhibited highly potent binding affinities for human OT receptors in vitro. In this study, we measured the ex vivo effects of FBOT and HPOT on contractions of uteri isolated from human cesarean delivery samples and virgin female mice. We evaluated the potency and efficacy of the analogs on uterine contraction, additivity with OT, and the ability to overcome the effects of atosiban, an OT antagonist. In human samples, the potency rank judged by the calculated EC50 (pM) was as follows: HPOT (189) > FBOT (556) > OT (5,340) > carbetocin (12,090). The calculated Emax was 86% for FBOT and 75% for HPOT (100%). Recovery from atosiban inhibition after HPOT treatment was as potent as that after OT treatment. HPOT showed additivity with OT. FBOT (56 pM) was found to be the strongest agonist in virgin mouse uterus. HPOT and FBOT demonstrated high potency and partial agonist efficacy in the human uterus. These results suggested that HPOT and FBOT are highly uterotonic for the human uterus and performed better than OT, indicating that they may prevent postpartum hemorrhage.

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.

Cost-effectiveness analysis of carbetocin for prevention of postpartum hemorrhage in a low-burden high-resource city of China

BACKGROUND

Postpartum hemorrhage (PPH) is a major cause of maternal morbidity, and oxytocin is the first-line uterotonic agent for PPH prevention. Clinical findings have reported carbetocin to reduce PPH risk without increasing risk of important side effects. Hong Kong is a low PPH burden and high-resource city in China. We aimed to examine the cost-effectiveness of PPH prevention with carbetocin from the perspective of Hong Kong public healthcare provider.

METHODS

A decision-analytic model was developed to simulate clinical and economic outcomes of carbetocin and oxytocin for PPH prevention in a hypothetical cohort of women at the third stage of labor following vaginal birth or Caesarean section (C-section). The model inputs were retrieved from literature and public data. Base-case analysis and sensitivity analysis were performed. The model time horizon was the postpartum hospitalization period. Primary model outcomes included PPH-related direct medical cost, PPH, hysterectomy, maternal death, and quality-adjusted life-year (QALY) loss.

RESULTS

In base-case analysis, carbetocin (versus oxytocin) reduced PPH-related cost (by USD29 per birth), PPH ≥500 mL and ≥1,500 mL (by 13.7 and 1.9 per 1,000 births), hysterectomy (by 0.15 per 1,000 births), maternal death (by 0.02 per 1,000 births), and saved 0.00059 QALY per birth. Relative risk of PPH ≥500 mL with carbetocin versus oxytocin, and proportion of child births by C-section were two influential parameters identified in deterministic sensitivity analysis. In probabilistic sensitivity analysis, carbetocin was accepted as cost-effective in >99.7% of the 10,000 Monte Carlo simulations at a willingness-to-pay threshold of zero USD/QALY.

CONCLUSION

PPH prevention with carbetocin appeared to reduce major unfavorable outcomes, and save cost and QALYs.

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 Relationship Between Pre-Operative Glycosylated Haemoglobin and Opioid Consumption After Caesarean Section in Women With Gestational Diabetes Mellitus

INTRODUCTION

Women with Gestational diabetes mellitus (GDM) had a higher need and consumption of analgesics than women without GDM. The preoperative level of HbA1c was associated with the postoperative consumption for analgesics in diabetic patients. This prospective observational study go further to investigate the relationship between the pre-operative HbA1c and the post-operative consumption for analgesics in women with GDM.

METHODS

Women with GDM and a singleton pregnancy undergoing elective cesarean section under combined spinal-epidural anaesthesia were divided into two groups based on pre-operative HbA1c: group HbA1c < 6% and group HbA1c ≥ 6%. Analgesics consumption, number of patient-controlled analgesia (PCA) compression, and pain scores in 6 hours and 24 hours post-operation were compared between the two groups. Then Pearson's correlation coefficient and a stepwise multivariate linear regression were performed to investigate possible independentpredictors of post-operative 24-hour sufentanil consumption.

RESULTS

Analgesics consumption was significantly lower (18.8 ± 0.4 vs 23.2 ± 4.3; 82.7 ± 2.4 vs 115.8 ± 17.4, P < 0.001), and number of PCA compressions was significantly less frequent (1 [1-2] vs 3 [1-5]; 5 [3-7] vs 7 [3-15], P < 0.001), and in group HbA1c < 6% than in group HbA1c ≥ 6% in 6 hours and 24 hours post-operation.The univariate analysis showed that sufentanil consumption at 24 hours post-operation was significantly related to pre-operative HbA1c (r = 0.338, P < 0.001) and parity (r = 0.184, P = 0.03) and was related to blood glucose management methods (r = 0.172, P = 0.043). Multivariate linear regression analysis showed that HbA1c was the independent factor related to post-operative 24-hour sufentanil consumption (adjusted r2 = 0.246, P < 0.001).

CONCLUSIONS

This study demonstrated that in pregnant women with GDM, the pre-operative HbA1c is independently related to the need for and consumption of analgesics in 24 hours after CS.

Effect of heat stable carbetocin vs oxytocin for preventing postpartum haemorrhage on post delivery hemoglobin-a randomized controlled trial

OBJECTIVE

To compare the effect of heat-stable carbetocin 100 μg IM versus oxytocin 10 IU IM on post-delivery hemoglobin level.

SETTING

Hospital based study in Southern India.

POPULATION

Women delivering vaginally who were enrolled in the WHO CHAMPION trial in a single facility in India. WHO CHAMPION Trial was a randomized, double-blind, noninferiority trial comparing intramuscular injections of heat-stable carbetocin with oxytocin administered immediately after vaginal birth in women across 23 sites in 10 countries.

METHODS

This was a nested randomized controlled trial designed to compare the effect of heat-stable carbetocin 100 μg IM versus oxytocin 10 IU IM, administered within one minute of vaginal delivery of the baby for prevention of postpartum hemorrhage, on post-delivery 48-72 h hemoglobin level, adjusted for pre-delivery hemoglobin level. 1,799 women from one hospital in India participated in this study.

RESULTS

Pre-delivery hemoglobin and postpartum blood loss were not significantly different between carbetocin and oxytocin. Post-delivery hemoglobin, unadjusted or adjusted for pre-delivery hemoglobin, was slightly lower for carbetocin (10.09 g/dL) compared to oxytocin (10.21) (p value of 0.0432). The drop in hemoglobin was slightly higher for carbetocin, although the difference was very small (1.2 g/dL for carbetocin, 1.1 g/dL for oxytocin) (p value of .0786). The proportion of participants with a drop in hemoglobin of 2 g/dL or more, adjusted for pre-delivery hemoglobin, was higher for carbetocin (RR = 1.29, 95% CI 1.02-1.63). From the regression coefficients it can be derived that post-delivery hemoglobin, adjusted for pre-delivery hemoglobin, decreases on average 0.12 g/dL for each dL of blood lost, for the two treatments combined.

CONCLUSION

The present ancillary study showed that intramuscular administration of 100 µg of heat stable carbetocin can result in a slightly lower post-delivery hemoglobin, slightly higher drop and higher percentage of women having a drop of 2 g/dL or larger, compared to 10 IU of oxytocin.

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.

The role of oxytocin, vasopressin, and their receptors at nociceptors in peripheral pain modulation

Oxytocin and vasopressin are neurohypophyseal hormones with sequence similarity and play a central role in bodily homeostatic regulation. Pain is currently understood to be an important phenotype that those two neurohormones strongly downregulate. Nociceptors, the first component of the ascending neural circuit for pain signals, have constantly been shown to be modulated by those peptides. The nociceptor modulation appears to be critical in pain attenuation, which has led to a gradual increase in scientific interest about their physiological processes and also drawn attention to their translational potentials. This review focused on what are recently understood and stay under investigation in the functional modulation of nociceptors by oxytocin and vasopressin. Effort to produce a nociceptor-specific view could help to construct a more systematic picture of the peripheral pain modulation by oxytocin and vasopressin.

Evaluating efficacy of intravenous carbetocin in reducing blood loss during abdominal myomectomy: a randomized controlled trial

OBJECTIVE

To evaluate the efficacy of carbetocin versus placebo in decreasing intraoperative blood loss and the need for blood transfusion during abdominal myomectomy.

DESIGN

Randomized, double-blind, placebo-controlled trial.

SETTING

Tertiary university hospital from September 2019 to February 2020.

PATIENT(S)

A total of 138 women with symptomatic leiomyoma who were candidates for abdominal myomectomy (n = 69 in each group).

INTERVENTION(S)

We randomized the study participants in a 1:1 ratio to carbetocin and placebo groups. Intravenous 100 μg carbetocin or placebo was administered slowly after induction of anesthesia.

MAIN OUTCOME MEASURE(S)

Intraoperative blood loss, need for blood transfusion, postoperative hemoglobin, operative time, length of hospitalization, and drug side-effects.

RESULT(S)

The baseline characteristics were similar among all groups. Carbetocin had significantly lower intraoperative blood loss compared with placebo (mean difference 184 mL). Hemoglobin level 24 hours after surgery was significantly lower in the placebo group than in the carbetocin group (9.1 ± 0.8 vs. 10.3 ± 0.6 g/dL). Eight women in the carbetocin group needed blood transfusion compared with 17 in placebo group. Operative time, length of hospitalization, and side-effects were similar in both groups.

CONCLUSION(S)

A single preoperative intravenous dose of 100 μg carbetocin is a simple, practical, and effective method of decreasing intraoperative blood loss and the need for blood transfusion during abdominal myomectomy, with tolerable, few, nonsignificant side-effects.

CLINICAL TRIAL REGISTRATION NUMBER

NCT04083625.

Oxytocin, eating behavior, and metabolism in humans

The hypothalamic peptide oxytocin has been increasingly recognized as a hormone and neurotransmitter with important effects on energy intake, metabolism, and body weight and is under investigation as a potential novel therapeutic agent for obesity. The main neurons producing oxytocin and expressing the oxytocin receptor are strategically located in brain areas known to be critically involved in homeostatic energy balance as well as hedonic and motivational aspects of eating behavior. In this chapter, we will review the central and peripheral physiology of oxytocin and the interaction of oxytocin with key hormones and neural circuitries that affect food intake and metabolism. Next, we will synthesize the available data on endogenous oxytocin levels related to caloric intake, body weight, and metabolic status. We will then review the effects of exogenous oxytocin administration on eating behavior, body weight, and metabolism in humans, including in healthy individuals as well as specific populations with suspected perturbations involving oxytocin pathways. Finally, we will address the promise and fundamental challenges of translating this line of research to clinical care.

UTEROTONIC DRUGS IN THE PREVENTION OF POSTPARTUM HEMORRHAGES

In the world practice, hemorrhages in obstetrics take leading positions within the causes of maternal morbidity and mortal ity. 800 women die every day due to childbirth complications under the data of the World Health Organization. The majority of maternal deaths occur during the perinatal period, usually within 24 hours postpartum. It is possible to prevent most of them. Lack of adequate pre-conceptional training, uncompensated extragenital diseases increase the percentage of pathological births. Consequently, practicing obstetricians-gynecologists have to face such childbirth complications as postpartum hemorrhage with increasing frequency. Uterine atonia is the main cause of postpartum hemorrhages. Uterotonic drugs administration enables to re- duce the risk of postpartum atonic hemorrhages. Particular attention should be paid to postpartum hemorrhage prevention, i.e. the use of uterotonic drugs as an integral part of the active management during the third period in natural labor and caesarean section.

The analgesic effect of tramadol combined with butorphanol on uterine cramping pain after repeat caesarean section: a randomized, controlled, double-blind study

PURPOSE

This study aimed to explore the effect of patient-controlled intravenous analgesia (PCIA) using tramadol combined with butorphanol on uterine cramping pain in women undergoing repeat caesarean section.

METHODS

A total of 126 patients, who were scheduled to undergo repeat caesarean section under spinal anesthesia, were included. PCIA using tramadol combined with butorphanol or sufentanil was randomly performed for postoperative pain control. Postoperative uterine cramping pain and wound pain within 48 h after surgery were evaluated. Postoperative analgesic consumption, early activity time, and length of hospital stay were also recorded and analyzed.

RESULTS

Uterine cramping pain intensity in women undergoing repeat caesarean section was significantly higher compared with their wound pain (P < 0.05). The mean visual analog scale (VAS) score for uterine cramping pain in the tramadol-butorphanol group was significantly lower than that in the sufentanil group at rest, and at 6 h and 12 h after surgery. VAS scores for uterine cramping pain during movement at 6 h, 12 h, and 24 h after surgery in the tramadol-butorphanol group were also significantly lower than that in sufentanil group (P < 0.05). There was no significant difference in VAS score for wound pain at the different time points between the tramadol-butorphanol and sufentanil groups (P > 0.05). Patient-controlled intravenous analgesia with tramadol accelerated early rehabilitation and decreased the length of hospital stay (P < 0.05).

CONCLUSION

PCIA using tramadol combined with butorphanol provided a better analgesic effect and accelerated postoperative rehabilitation compared with sufentanil, and may be an optimal analgesic strategy for women undergoing repeat caesarean section.

CLINICAL TRIAL REGISTRATION

The trial was registered at Chinese Clinical Trial Registry ( www.chictr.org.cn ) with ID: ChiCTR-1800014986.

Oxytocin in the Male Reproductive Tract; The Therapeutic Potential of Oxytocin-Agonists and-Antagonists

In this review, the role of oxytocin and oxytocin-like agents (acting via the oxytocin receptor and belonging to the oxytocin-family) in the male reproductive tract is considered. Previous research (dating back over 60 years) is revised and connected with recently found aspects of the role oxytocin plays in male reproductive health. The local expression of oxytocin and its receptor in the male reproductive tract of different species is summarized. Colocalization and possible crosstalk to other agents and receptors and their resulting effects are discussed. The role of the newly reported oxytocin focused signaling pathways in the male reproductive tract, other than mediating contractility, is critically examined. The structure and effect of the most promising oxytocin-agonists and -antagonists are reviewed for their potential in treating male disorders with origins in the male reproductive tract such as prostate diseases and ejaculatory disorders.

Oxytocin Elicits Itch Scratching Behavior via Spinal GRP/GRPR System

Oxytocin (OT), a neuropeptide involved in the regulation of complex social and sexual behavior in mammals, has been proposed as a treatment for a number of psychiatric disorders including pain. It has been well documented that central administration of OT elicits strong scratching and grooming behaviors in rodents. However, these behaviors were only described as symptoms, few studies have investigated their underlying neural mechanisms. Thus, we readdressed this question and undertook an analysis of spinal circuits underlying OT-induced scratching behavior in the present study. We demonstrated that intrathecal OT induced robust but transient hindpaw scratching behaviors by activating spinal OT receptors (OTRs). Combining the pre-clinical and clinical evidence, we speculated that OT-induced scratching may be an itch symptom. Further RNAscope studies revealed that near 80% spinal GRP neurons expressed OTRs. OT activated the expression of c-fos mRNA in spinal GRP neurons. Chemical ablation of GRPR neurons significantly reduced intrathecal OT-induced scratching behaviors. Given GRP/GRPR pathway plays an important role in spinal itch transmission, we proposed that OT binds to the OTRs expressed on the GRP neurons, and activates GRP/GRPR pathway to trigger itch-scratching behaviors in mice. These findings provide novel evidence relevant for advancing understanding of OT-induced behavioral changes, which will be important for the development of OT-based drugs to treat a variety of psychiatric disorders.

Repeated Cesarean Delivery Predicted a Higher Risk of Inadequate Analgesia Than Primary Cesarean Delivery: A Retrospective Study with Propensity Score Match Analysis

Purpose

This study aimed to compare the analgesic outcomes between primary and repeated cesarean delivery.

Patients and Methods

We performed a retrospective analysis based on the medical records of a teaching hospital in China from January 2018 to March 2019. We collected data on demographic characteristics, perioperative complications, anesthesia, and surgical factors for cesarean delivery patients. We also recorded the postoperative analgesic strategy, pain intensity (assessed by the number rating scale) during the first 48 hrs after surgery, hospital cost, and hospital stay. Postoperative inadequate analgesia was defined by a score of ≥ 4 in the number rating scale. Analgesic outcomes after cesarean delivery between primiparas and multiparas were compared using propensity score matching analysis. Moreover, subgroup logistic analysis for different age groups (≥ 35 and < 35 years) was performed to investigate the effect of the maternal category on postoperative inadequate analgesia.

Results

A total of 1543 patients were included in the analysis and 571 pairs (1142 patients) were matched in the primiparas and multiparaparas group according to their propensity score. In both the non-matched and matched cohort, the incidence of inadequate analgesia in the primiparas group was lower than that in the multiparas group (16.7% vs. 24.0%, P < 0.001 and 16.1% vs. 23.5%, P = 0.002; respectively). The multiparas group was identified as being at risk of inadequate analgesia after cesarean delivery in both age groups (age ≥ 35 years, odds ratio: 2.18, 95% confidence interval: 1.20–3.95; age < 35 years, odds ratio: 1.43, 95% confidence interval 1.08–1.89).

Conclusion

Multiparas that undergo a repeat cesarean delivery had a significantly higher risk of inadequate postoperative pain treatment than primiparas. The maternal category should be considered when formulating the postoperative analgesia strategy after cesarean delivery.

Carbetocin versus rectal misoprostol for management of third stage of labor among women with low risk of postpartum hemorrhage

OBJECTIVE

To compare effectiveness and safety of carbetocin and misoprostol for prevention of postpartum hemorrhage (PPH) among low-risk women.

METHODS

Randomized controlled trial among 150 pregnant women with low risk of PPH admitted for vaginal delivery at Kasr Al Ainy Hospital, Cairo, Egypt, between July 2018 and May 2019. Participants were assigned to two groups by a web-based randomization system ensuring allocation concealment. After neonatal delivery, the carbetocin group received one ampoule of carbetocin (100 μg/mL) intravenously and the misoprostol group received two rectal tablets of misoprostol (800 μg) for active management of the third stage. Blood pressure, blood loss, and hemoglobin levels were monitored. The primary outcome measure was need for additional uterotonic drugs.

RESULTS

The carbetocin group had significantly less blood loss (P<0.001), shorter third stage (P<0.001), and less need for additional uterotonics (P=0.013) or uterine massage (P=0.007). The two drugs were hemodynamically safe. Hemoglobin levels after delivery were comparable in the two groups (P=0.475). Adverse effects were more common in the misoprostol group (P<0.001).

CONCLUSION

Among low-risk women, carbetocin seems to be a better alternative to misoprostol for active management of the third stage of labor; it reduced blood loss and use of additional uterotonic drugs. CLINICALTRIALS.GOV: NCT03556852.

Comparison of postoperative pain between patients who underwent primary and repeated cesarean section: a prospective cohort study

BACKGROUND

The differences in post-operative pain are unclear between the primiparas who underwent a primary cesarean section and multiparas who underwent their first repeat cesarean section. The study aimed to explore the possible differences in postoperative pain between primiparas and multiparas.

METHODS

A prospective cohort study was performed only including women who underwent cesarean deliveries under spinal anesthesia. Postoperative patient-controlled intravenous analgesia (PCIA) was administered to all subjects with 0.2 mg/kg hydromorphone and 4 mg/kg flurbiprofen; the pump was programmed as 2.0 mL/h background infusion with a loading dose of 1 mL and a lockout period of 15 min. Postoperative incision and visceral pain intensity were evaluated using the visual analogue scale, and inadequate analgesia was defined as a visual analogue scale score ≥ 40 during 48 h post-operation. Additionally, the patients' pain statuses in postoperative week 1 and week 4 were also assessed during follow-up via telephone.

RESULTS

From January to May 2017, a total of 168 patients (67 primiparas and 101 multiparas) were included. The relative risk for multiparas to experience inadequate analgesia on incision pain was 0.42 (95% CI: 0.25 to 0.74) compared to primiparas. In patients aged < 30 years, inadequate analgesia on visceral pain was higher in multiparas than in primiparas (RR, 3.56 [1.05 to 12.04], P = 0.025). There was no significant difference in the combined incidence of inadequate analgesia in both types of pain between the multiparas and primiparas (33.7% vs. 40.2%, P = 0.381). No difference was found in PCIA use between the two groups (111.1 ± 36.0 mL vs. 110.9 ± 37.3 mL, P = 0.979). In addition, a significantly higher incidence of pain was noted 4 weeks post-surgery in primiparas than that in multiparas (62.2% vs. 37.7%, P = 0.011).

CONCLUSION

Multiparas who underwent their first repeat cesarean section have a lower for inadequate analgesia on incision pain during the first 48 h after surgery than primiparas. Multiparas aged under 30 years may be more prone to experiencing postoperative inadequate analgesia on visceral pain.

TRAIL REGISTRATION

ClinicalTrial.gov: NCT03009955 , Date registered: December 30, 2016.

Appropriate Documentation of the Timing of Events in the Management of Women with Postpartum Hemorrhage in Aminu Kano Teaching Hospital: A 2-Year Audit

Background:

Appropriate documentation of the timing of events in the management of women with postpartum hemorrhage (PPH) is associated with better outcome.

Objective:

To find out how best the Department of Obstetrics and Gynaecology, Aminu Kano Teaching Hospital, fares when compared with the Royal College of Obstetricians and Gynaecologists (RCOG) guidelines about appropriate documentation of the timing of events in the management of PPH.

Methodology:

It was a retrospective study based on findings obtained from the case folders of women who had PPH between January 2016 and December 2017. A structured pro forma was used to extract information such as personal data, type of PPH, vital signs of patients, sequence of events, administration of pharmacological agents, and timing of interventions.

Results:

There were 5202 patients who presented to the labor ward, and 129 of them were cases of PPH giving an incidence of 2.48%. The mean age of the patients was 20.38 ± 1.13 years, and about half of them (47.6%) were multiparas. There was appropriate documentation in terms of initial assessment, resuscitation, and investigations as the percentages of standards achieved are 85%, 78.6%, and 85.7%, respectively. Sixty-one percent of the patients had treatment within the time recommended and 56% had treatment with appropriate uterotonics. Appropriate documentation of major surgeries according to the guidelines was achieved in 12% of cases.

Conclusion:

There was good performance in documentation of initial management of patients with PPH when compared with the RCOG guidelines but suboptimal performance in timing of major surgical interventions.

Development of a Highly Potent Analogue and a Long-Acting Analogue of Oxytocin for the Treatment of Social Impairment-Like Behaviors

The nonapeptide hormone oxytocin (OT) has pivotal brain roles in social recognition and interaction and is thus a promising therapeutic drug for social deficits. Because of its peptide structure, however, OT is rapidly eliminated from the bloodstream, which decreases its potential therapeutic effects in the brain. We found that newly synthesized OT analogues in which the Pro⁷ of OT was replaced with N-( p-fluorobenzyl)glycine (2) or N-(3-hydroxypropyl)glycine (5) exhibited highly potent binding affinities for OT receptors and Ca²⁺ mobilization effects by selectively activating OT receptors over vasopressin receptors in HEK cells, where 2 was identified as a superagonist ( E_Max = 131%) for OT receptors. Furthermore, the two OT analogues had a remarkably long-acting effect, up to 16-24 h, on recovery from impaired social behaviors in two strains of CD38 knockout mice that exhibit autism spectrum disorder-like social behavioral deficits, whereas the effect of OT itself rapidly diminished.

Design of Oxytocin Analogs

The neurohypophyseal hormone oxytocin (OT) and related modulators of the oxytocin receptor (OTR) have been the subject of intensive research for nearly seven decades. Despite having rather poor drug-like properties, OT is used as a treatment for labor induction, postpartum hemorrhage, and lactation support. The potential use of OT in the treatment of central nervous system (CNS)-related diseases has recently renewed interest in the pharmacology of OT. Oxytocin is one of the most extensively studied cyclic peptides and since the elucidation of its structure in 1953 thousands of peptidic OT analogs with antagonistic and agonistic properties have been synthesized and biologically evaluated. Among them are atosiban, a mixed oxytocin receptor (OTR)/vasopressin 1a receptor (V_1aR) antagonist used as a tocolytic agent approved (in certain countries), and carbetocin, a longer acting OTR agonist on the market for the treatment of postpartum hemorrhage. Many other OT analogs with improved pharmacological properties (e.g., barusiban, Antag III) have been identified. These peptides have been tested in clinical trials and/or used as pharmacological tools. In this chapter, the modifications of the OT molecule that led to the discovery of these compounds are reviewed.

Motherwort injection for preventing postpartum hemorrhage in pregnant women with cesarean section: A systematic review and meta-analysis

OBJECTIVE

To assess the impact of motherwort injection alone or combined with oxytocin for preventing postpartum hemorrhage in pregnant women with caesarean section.

METHODS

A systematic review and meta-analysis of randomized trials were performed. PubMed, EMbase, The Cochrane Central Register of Controlled Trials (CENTRAL), Chinese database Sino-Med, Chinese National Knowledge Infrastructure Database (CNKI), VIP Chinese Science and Technique Journals Database, WanFang, and ClinicalTrials.gov were searched. Randomized controlled trials (RCTs) that compared motherwort injection alone or motherwort injection combined with oxytocin in pregnant women receiving cesarean section were included. Paired reviewers independently screened abstracts and full texts for eligibility, assessed risk of bias, and extracted data. We performed random-effects meta-analyses of RCTs along with a limited number of prespecified subgroup hypotheses, and sensitivity analyses were carried out with other statistical approaches.

RESULTS

Forty-six RCTs (n = 7359) proved eligible. Compared with oxytocin, both motherwort injection and motherwort injection combined with oxytocin had a significantly lower blood loss within 2 hours (MD = -21.81, 95% CI -37.05 to -6.58 and MD = -53.04, 95% CI -61.68 to -44.39); lower blood loss within 24 hours (MD = -25.44, 95% CI -39.38 to -11.51 and MD = -67.81, 95% CI -78.02 to -57.60); and lower the risk of adverse events (OR_Peto 0.40, 95% CI 0.16 to 0.96 and OR_Peto 0.50, 95% CI 0.35 to 0.71). Motherwort injection combined with oxytocin also decreased the risk of postpartum hemorrhage (OR 0.22, 95% CI 0.14 to 0.35.) CONCLUSIONS: In pregnant women with cesarean section, motherwort injection suggests an obvious benefit and less adverse event.

Prostaglandin D2 evokes potent uterine contraction via the F prostanoid receptor in postpartum rats

Prostaglandin (PG) D₂, a prostanoid known to have hypotensive effect, can evoke increased in vitro prepartum myometrial contraction resulting from up-regulation of the F prostanoid (FP) receptor. The present study further determined postpartum rat uterine responses to PGD₂ to evaluate the possibility of the prostanoid becoming a therapeutic for postpartum uterine atony, a major cause of postpartum hemorrhage that can lead to maternal morbidity. In vitro and in vivo postpartum uterine responses to PGD₂ were determined and compared to those of prepartum rats. Here we show that in postpartum myometrial strips PGD₂ did evoke a contraction sensitive to FP receptor antagonism. Interestingly, this response was not only to a greater extent than that of prepartum rats, but also comparable with the contraction obtained with PGF_2α, a therapeutic for postpartum uterine atony but contradicted in conditions including hypertension. Indeed, PGD₂ was also found to cause increases of basal uterine contraction under in vivo conditions. Western blots revealed that the expression of FP receptors in postpartum myometrium was higher than that of prepartum rats. Moreover, we noted that the amount of PGD₂ produced in postpartum uteri, although lower than that of prepartum rats, was increased compared to non-pregnant conditions. These results thus demonstrate that due to a further up-regulation or high expression of myometrial FP receptors, PGD₂ can evoke potent uterine contraction postpartum, and hence the prostanoid, which is naturally synthesized in uterine tissues, could be a potential therapeutic for postpartum uterine atony, especially in settings, such as hypertension.

Hybrid peptide-small molecule oxytocin analogs are potent and selective agonists of the oxytocin receptor

Oxytocin (OT) is a peptide hormone agonist of the oxytocin receptor (OTR) that has been proposed as a therapeutic to treat a number of social and emotional disorders in addition to its current clinical use to induce labor and treat postpartum bleeding. OT is administered intravenously and intranasally rather than orally, in part because its low passive permeability causes low oral bioavailability. Non-peptidic OTR agonists have also been reported, but none with the exquisite potency of the peptide based agonists. In this report, we describe the OTR agonist activity and exposed polarity of a set of truncated OT analogs as well as hybrid peptide-small molecule analogs of OT. Examples of both truncated analogs and peptide-small molecule hybrid analogs are potent and selective OTR agonists. Hybrid agonist 13, which is 232 Da smaller than OT, still retains subnanomolar potency, full agonist activity, and selectivity over V1a. While these compounds were designed to address the low permeability of OT and other full length analogs, we found that reduction in molecular weight and the removal or replacement of the three amino acid tail of OT did not have a significant effect on passive permeability.

Efficacy of oxytocin versus carbetocin in prevention of postpartum hemorrhage after cesarean section under general anesthesia: a prospective randomized clinical trial

OBJECTIVE

To compare the use of carbetocin and oxytocin in the prevention of postpartum hemorrhage after cesarean section.

METHODS

The present study was a prospective double-blind randomized controlled clinical trial performed in two university-based hospitals in Tehran, Iran. Two hundred and twenty women with the gestational age of more than 37 weeks, who needed cesarean operation, participated in the study. Patients were assigned to receive either a single 100 μg IV dose of carbetocin or a standard 30-international unit IV infusion of oxytocin during 2 h after delivery of placenta. The primary outcome measures were postpartum hemorrhage requiring additional uterotonic drugs, bleeding volume, and the hemoglobin drops.

RESULTS

There were meaningful differences in carbetocin versus oxytocin group regarding the hemoglobin drops (1.01 versus 2.05, p = .01), bleeding volume (430.68 CC versus 552.6 CC, p < .001), uterine massages frequency (3.7 versus 4.26, p < .001), and uterine height at 2, 4, and 24 h (p < .001). Oxytocin side effects were significantly higher in comparison with the carbetocin except pruritus which was observed in 27% of patients in the carbetocin versus no cases in the oxytocin group.

CONCLUSIONS

It may be concluded that carbetocin is a good alternative modality to conventional uterotonic agents such as oxytocin for the prevention of postpartum hemorrhage after cesarean sections. Registration ID in IRCT: NCT02079558.

[Carbetocin versus Oxytocin during caesarean section for preventing postpartum haemorrhage]

OBJECTIVES

The aim of the study was to compare the effectiveness of Carbetocin versus Oxyotcin during caesarean section for preventing postpartum haemorrhage.

METHODS

Prospective observational study (before/after design). Five hundred and forty patients who received an injection of Oxytocin were compared to 262 patients with single injection of 100 micrograms of Carbetocin. The primary outcome was to compare the differential hematocrit level between pre- and postoperative blood samples. The secondary outcome was to compare differential hemoglobin level and the use of complementary therapies for postpartum haemorrhage.

RESULTS

We did not find any difference between the Oxytocin and Carbetocin groups on differential hematocrit level. There was no difference between the groups regarding the use of additionnal therapies (Sulproston injections, blood transfusions and surgery methods). The rate of postpartum haemorrhage was similar in the two groups (18.7% vs 21.6%; P=0.33). We found a lower percentage of patients with differential of hemoglobin level between 2 g/dL and 4 g/dL in the Carbetocin group (6.5% vs 15.6%, P<0.001). The proportion of patients requiring intravenous iron administration was significantly lower in the Carbetocin group (6.8% vs 13.8%, P=0.0036) CONCLUSION: According to the primary outcome, there is no difference in effectiveness between carbetocin and oxytocin. Carbetocin seems to reduce the need for postoperative intravenous iron injection.

Oxytocin: its mechanism of action and receptor signalling in the myometrium

Oxytocin is a nonapeptide hormone that has a central role in the regulation of parturition and lactation. In this review, we address oxytocin receptor (OTR) signalling and its role in the myometrium during pregnancy and in labour. The OTR belongs to the rhodopsin-type (Class 1) of the G-protein coupled receptor superfamily and is regulated by changes in receptor expression, receptor desensitisation and local changes in oxytocin concentration. Receptor activation triggers a number of signalling events to stimulate contraction, primarily by elevating intracellular calcium (Ca(2+) ). This includes inositol-tris-phosphate-mediated store calcium release, store-operated Ca(2+) entry and voltage-operated Ca(2+) entry. We discuss each mechanism in turn and also discuss Ca(2+) -independent mechanisms such as Ca(2+) sensitisation. Because oxytocin induces contraction in the myometrium, both the activation and the inhibition of its receptor have long been targets in the management of dysfunctional and preterm labours, respectively. We discuss current and novel OTR agonists and antagonists and their use and potential benefit in obstetric practice. In this regard, we highlight three clinical scenarios: dysfunctional labour, postpartum haemorrhage and preterm birth.

Treatment for primary postpartum haemorrhage

BACKGROUND

Primary postpartum haemorrhage (PPH) is one of the top five causes of maternal mortality in both developed and developing countries.

OBJECTIVES

To assess the effectiveness and safety of any intervention used for the treatment of primary PPH.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 August 2013).

SELECTION CRITERIA

Randomised controlled trials comparing any interventions for the treatment of primary PPH.

DATA COLLECTION AND ANALYSIS

We assessed studies for eligibility and quality and extracted data independently. We contacted authors of the included studies to request more information.

MAIN RESULTS

Ten randomised clinical trials (RCTs) with a total of 4052 participants fulfilled our inclusion criteria and were included in this review.Four RCTs (1881 participants) compared misoprostol with placebo given in addition to conventional uterotonics. Adjunctive use of misoprostol (in the dose of 600 to 1000 mcg) with simultaneous administration of additional uterotonics did not provide additional benefit for our primary outcomes including maternal mortality (risk ratio (RR) 6.16, 95% confidence interval (CI) 0.75 to 50.85), serious maternal morbidity (RR 0.34, 95% CI 0.01 to 8.31), admission to intensive care (RR 0.79, 95% CI 0.30 to 2.11) or hysterectomy (RR 0.93, 95% CI 0.16 to 5.41).  Two RCTs (1787 participants) compared 800 mcg sublingual misoprostol versus oxytocin infusion as primary PPH treatment; one trial included women who had received prophylactic uterotonics, and the other did not. Primary outcomes did not differ between the two groups, although women given sublingual misoprostol were more likely to have additional blood loss of at least 1000 mL (RR 2.65, 95% CI 1.04 to 6.75). Misoprostol was associated with a significant increase in vomiting and shivering.Two trials attempted to test the effectiveness of estrogen and tranexamic acid, respectively, but were too small for any meaningful comparisons of pre-specified outcomes.One study compared lower segment compression but was too small to assess impact on primary outcomes.We did not identify any trials evaluating surgical techniques or radiological interventions for women with primary PPH unresponsive to uterotonics and/or haemostatics.

AUTHORS' CONCLUSIONS

Clinical trials included in the current review were not adequately powered to assess impact on the primary outcome measures. Compared with misoprostol, oxytocin infusion is more effective and causes fewer side effects when used as first-line therapy for the treatment of primary PPH. When used after prophylactic uterotonics, misoprostol and oxytocin infusion worked similarly. The review suggests that among women who received oxytocin for the treatment of primary PPH, adjunctive use of misoprostol confers no added benefit.The role of tranexamic acid and compression methods requires further evaluation. Furthermore, future studies should focus on the best way to treat women who fail to respond to uterotonic therapy.

A comparison of oxytocin and carboprost tromethamine in the prevention of postpartum hemorrhage in high-risk patients undergoing cesarean delivery

The aim of this study was to compare carboprost with oxytocin for the prevention of postpartum hemorrhage (PPH) in females with a high risk of PPH undergoing cesarean delivery. Patients were randomly divided into three groups that received different uterotonics (oxytocin, carboprost and oxytocin plus carboprost) during cesarean section, following the delivery of the infant. A total of 117 females (age range, 19-40 years) at 35-40 weeks gestation who delivered by cesarean between December, 2010 and May, 2012 were included in this study. There were 29 cases of twins, 12 cases of polyhydramnios, 23 cases of placenta previa and 53 cases of fetal macrosomia. There were 37 patients in the oxytocin group, 36 in the carboprost group and 44 in the oxytocin plus carboprost group. No significant differences were identified in maternal age, gravidity/parity, gestational age and reason for cesarean delivery between the three groups. The median blood loss in the oxytocin, carboprost and oxytocin plus carboprost groups was 610, 438 and 520 ml, respectively. The blood loss in the carboprost group was significantly lower than that in the oxytocin and oxytocin plus carboprost groups (both P<0.05). Vomiting occurred in eight patients from the carboprost group, two from the oxytocin group and two from the oxytocin plus carboprost group (P=0.036). Carboprost was more effective than oxytocin in preventing PPH in high-risk patients undergoing cesarean delivery.

Carbetocin vs. Syntometrine in Prevention of Postpartum Hemorrhage: a Double Blind Randomized Control Trial

Background

Postpartum hemorrhage is a significant cause of maternal mortality and morbidity, worldwide.

Objectives

The aim of this study was to compare the efficacy between carbetocin and syntometrine in prevention of postpartum hemorrhage.

Materials and Methods

This study was a double blind randomized clinical trial that carried out on 200 pregnant women referred to Shabiehkhani maternity center of Kashan, during 2011. The first group received intramuscular syntometrine and the second group received intramuscular carbetocin after placental delivery. All of the participants were followed for 24 hours and blood pressure, pulse rate, uterine tone, hemoglobin concentration at first and 24 hours after delivery, and the need for additional uterotonic drugs and drug side effects were evaluated. Finally all data were analyzed using t-test, chi square tests and logistic regression.

Results

The mean fall in hemoglobin level in the carbetocin group was significantly lower than the syntometrine group (P < 0.001). Also there were significant differences between the two groups, regarding additional uterotonic drug requirements (P = 0.002). Moreover systolic blood pressure and uterine tone immediately and 30 minutes after drug administration were significantly different (P < 0.001). Incidence rate of tachycardia in the carbetocin group was 13%, in contrast to 5% in the syntometrine group (P = 0.04).

Conclusions

This study revealed that carbetocin is more effective than syntometrine in prevention of postpartum hemorrhages. Thus it can be used as a good alternative of syntometrine for low-risk women.

Changes in Blood Pressure and Cardiac Output during Cesarean Delivery

Background:

Little is known about maternal hemodynamics after Cesarean delivery. Uterine contractions may increase cardiac output. Oxytocin is the first-line treatment for uterine atony, although the effects of the long-acting oxytocin analogue carbetocin are comparable with that of oxytocin. The authors analyzed the effects of i.v. oxytocin 5 U, carbetocin 100 µg, and placebo on hemodynamics, uterine tone, adverse events, and blood loss after Cesarean delivery.

Methods:

This was a randomized, double-blinded, placebo-controlled, parallel-group comparison of carbetocin and oxytocin after elective Cesarean delivery of singletons under spinal anesthesia (n = 76). Continuously measured invasive systolic arterial pressure was the primary outcome measure.

Results:

The mean systolic arterial pressure decrease was 28 mmHg (95% CI, 22–34) after oxytocin and 26 mmHg (95% CI, 20–31) after carbetocin. The decrease was greatest after 80 (95% CI, 71–89) and 63 s (95% CI, 55–72), respectively (P = 0.006). The differences were nearly undetectable after 2.5 min, although the effect of carbetocin was slightly greater than placebo (P &lt; 0.001). The group differences in systolic arterial pressure decreased over 5 min and were gone at 1 h. Heart rate and cardiac output increased in all three groups. Stroke volume increased after oxytocin and carbetocin but was unchanged after placebo.

Conclusions:

The hemodynamic side effects of oxytocin 5 U and carbetocin 100 µg were comparable. The lack of an increase in stroke volume in the placebo group challenges the theory that uterine contraction causes autotransfusion of uterine blood, leading to an increase in preload.

Carbetocin in comparison with oxytocin in several dosing regimens for the prevention of uterine atony after elective caesarean section in the Netherlands

PURPOSE

The aim of the study was to compare the prophylactic effects of carbetocin with those of oxytocin for the prevention of uterine atony in patients undergoing elective caesarean section (CS) in the Netherlands. The primary endpoint was the need for additional uterotonic medication.

METHODS

Each of the five participating Dutch hospitals treated 50-100 term patients with 100 μg of intravenous carbetocin on prescription. Each centre retrieved charts of 250 patients treated with oxytocin according to the hospital's policy for the prevention of uterine atony (oxytocin bolus 5 IU, bolus 10 IU or bolus 5 IU followed by 10 IU in 2 h).

RESULTS

In the carbetocin group 462 subjects were included and in the oxytocin group 1,122. The proportion of subjects needing additional uterotonic treatment was 3.1 % (95 % CI 1.7-5.1 %) after carbetocin and 7.2 % (5.8-8.9 %) after oxytocin; relative risk 0.41 (0.19-0.85); p = 0.0110. Carbetocin was most effective compared with the oxytocin 5 IU bolus subgroup with less need for additional uterotonic medication (3.1 vs. 9.3 %, p = 0.0067) and blood transfusions (2.2 vs. 3.6 %, p = 0.0357).

CONCLUSIONS

Compared with oxytocin, prophylaxis of uterine atony with carbetocin after an elective CS diminished the need for additional uterotonics by more than 50 %.