The effects of routine oxytocic administration in the management of the third stage of labour: an overview of the evidence from controlled trials

A Comparative Study of the Efficacy of Intraoperative Intravenous Oxytocin and Intramuscular Oxytocin Versus Conventional Intramuscular Oxytocin for Third-Stage Labour in Elective Cesarean Section

Objective  To study the efficacy of intraoperative IV oxytocin and intramuscular (IM) oxytocin versus conventional intramuscular oxytocin alone for active management of the third stage of labor in lower segment cesarean section (CS). The study was performed to determine the effect of 5 IU (International Unit) oxytocin infusion at the time of skin incision and that of 10 IU IM oxytocin infusion after delivery in reducing blood loss during and after CS, in comparison with the effect of administrating conventional 10 IU IM oxytocin in the same time period. In addition, it assessed the ability of the IV+IM oxytocin group to reduce the need for additional uterotonic as well as its safety determination and postoperative blood transfusion in CS. Materials and methods It is a randomized control study. The effect of 5 IU of oxytocin infusion at the time of skin incision and 10 IU of IM oxytocin (IV+IM) in reducing blood loss during and after the CS was compared to conventional 10 IU IM oxytocin. Results The study showed that the IV+IM group had a mean blood loss of 316.5 ± 74.36 ml, while the IM group had a mean loss of 403.90 ± 107.2 ml (p-value < 0.001) from placental delivery to the end of CS. A total of 90% of the patients in the IV+IM group had blood loss <50 ml compared to 95% of patients in the IM group who had a blood loss between 50 and 100 ml range from the end of cesarean to two hours postpartum. When total blood loss was compared in both groups, 84% of patients had a blood loss between 300 and 400 ml, compared to 81% of the patients in the IM group who had blood loss of 400-500 ml. Total blood loss in the IM group was 483.20 ± 115.86 ml, which was significantly higher compared to the IV group, 362.60 ± 78.07 ml (p-value=<0.001). Conclusion 5IU oxytocin infusion at the time of skin incision and 10 IU IM oxytocin after delivery of the baby significantly reduced the amount of blood loss, need for blood transfusion, and additional uterotonics during and after lower segment CS.

Trends and regional variations in prescriptions dispensed to stimulate uterine contractions at the end of pregnancy in Belgium: A community-based study from 2003 to 2018

PURPOSE

To investigate trends and regional variations in uterotonics dispensed around birth between 2003 and 2018 in Belgium.

METHODS

Data, including outpatient and inpatient prescriptions were extracted from a nationally representative prescription database. The prevalence of uterotonics dispensed during a period including the 7 days before birth, the delivery day and the 7 days after birth was computed over three 4-year-long study periods from 2003 to 2018. The trends between periods and associations between the use of at least one uterotonic and maternal age, region of residence, delivery type and social status were assessed using logistic regression.

RESULTS

In total, 31 675 pregnancies were included in the study. The proportion of pregnancies exposed to at least one uterotonic decreased significantly from 92.9% (95%CI, 92.3-93.4) in 2003-2006 to 91.4% (95%CI, 90.7-92.0) in 2015-2018 for vaginal births and from 95.5% (95%CI, 94.5-96.4) to 93.7% (95%CI, 92.6-94.7) for caesarean sections. However, for vaginal births, the proportion of oxytocin increased from 84.5% (95%CI, 83.7-85.2) to 89% (95%CI 88.3-89.7). A significant association was found between uterotonic agent use and maternal age, region of residence, and delivery type. The dispensation of some uterotonic agents differed significantly between the regions.

CONCLUSIONS

The proportion of pregnancies exposed to at least one uterotonic was high across the study period but decreased slightly between 2003 and 2018. Important variations in uterotonic use between regions highlight the need for improved national guidance.

Prophylactic oxytocin for the third stage of labour to prevent postpartum haemorrhage

BACKGROUND

Active management of the third stage of labour reduces the risk of postpartum blood loss (postpartum haemorrhage (PPH)), and is defined as administration of a prophylactic uterotonic, early umbilical cord clamping and controlled cord traction to facilitate placental delivery. The choice of uterotonic varies across the globe and may have an impact on maternal outcomes. This is an update of a review first published in 2001 and last updated in 2013.

OBJECTIVES

To determine the effectiveness of prophylactic oxytocin to prevent PPH and other adverse maternal outcomes in the third stage of labour.

SEARCH METHODS

For this update, we searched Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov, WHO International Clinical Trials Registry Platform (ICTRP) (6 March 2019) and reference lists of retrieved studies.

SELECTION CRITERIA

Randomised, quasi- or cluster-randomised trials including women undergoing vaginal delivery who received prophylactic oxytocin during management of the third stage of labour. Primary outcomes were blood loss 500 mL or more after delivery, need for additional uterotonics, and maternal all-cause mortality.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion, extracted data, and assessed trial quality. Data were checked for accuracy. We assessed the quality of the evidence using the GRADE approach.

MAIN RESULTS

This review includes 24 trials, with 23 trials involving 10,018 women contributing data. Due to many trials assessed at high risk of bias, evidence grade ranged from very low to moderate quality.Prophylactic oxytocin versus no uterotonics or placebo (nine trials)Prophylactic oxytocin compared with no uterotonics or placebo may reduce the risk of blood loss of 500 mL after delivery (average risk ratio (RR) 0.51, 95% confidence interval (C) 0.37 to 0.72; 4162 women; 6 studies; Tau² = 0.10, I² = 75%; low-quality evidence), and blood loss 1000 mL after delivery (RR 0.59, 95% CI 0.42 to 0.83; 4123 women; 5 studies; low-quality evidence). Prophylactic oxytocin probably reduces the need for additional uterotonics (average RR 0.54, 95% CI 0.36 to 0.80; 3135 women; 4 studies; Tau² = 0.07, I² = 44%; moderate-quality evidence). There may be no difference in the risk of needing a blood transfusion in women receiving oxytocin compared to no uterotonics or placebo (RR 0.88, 95% CI 0.44 to 1.78; 3081 women; 3 studies; low-quality evidence). Oxytocin may be associated with an increased risk of a third stage greater than 30 minutes (RR 2.55, 95% CI 0.88 to 7.44; 1947 women; 1 study; moderate-quality evidence), however the confidence interval is wide and includes 1.0, indicating that there may be little or no difference.Prophylactic oxytocin versus ergot alkaloids (15 trials)It is uncertain whether oxytocin reduces the likelihood of blood loss 500 mL (average RR 0.84, 95% CI 0.56 to 1.25; 3082 women; 10 studies; Tau² = 0.14, I² = 49%; very low-quality evidence) or the need for additional uterotonics compared to ergot alkaloids (average RR 0.89, 95% CI 0.43 to 1.81; 2178 women; 8 studies; Tau² = 0.76, I² = 79%; very low-quality evidence), because the quality of this evidence is very low. The quality of evidence was very low for blood loss of 1000 mL (RR 1.13, 95% CI 0.63 to 2.01; 1577 women; 3 studies; very low-quality evidence), and need for blood transfusion (average RR 1.37, 95% CI 0.34 to 5.51; 1578 women; 7 studies; Tau² = 1.34, I² = 45%; very low-quality evidence), making benefit of oxytocin over ergot alkaloids uncertain. Oxytocin probably increases the risk of a prolonged third stage greater than 30 minutes (RR 4.69, 95% CI 1.63 to 13.45; 450 women; 2 studies; moderate-quality evidence), although it is uncertain if this translates into increased risk of manual placental removal (average RR 1.10, 95% CI 0.39 to 3.10; 3127 women; 8 studies; Tau² = 1.07, I² = 76%; very low-quality evidence). Oxytocin may make little or no difference to risk of diastolic blood pressure > 100 mm Hg (average RR 0.28, 95% CI 0.04 to 2.05; 960 women; 3 studies; Tau² = 1.23, I² = 50%; low-quality evidence), and is probably associated with a lower risk of vomiting (RR 0.09, 95% CI 0.05 to 0.14; 1991 women; 7 studies; moderate-quality evidence), although the impact of oxytocin on headaches is uncertain (average RR 0.19, 95% CI 0.03 to 1.02; 1543 women; 5 studies; Tau² = 2.54, I² = 72%; very low-quality evidence).Prophylactic oxytocin-ergometrine versus ergot alkaloids (four trials)Oxytocin-ergometrine may slightly reduce the risk of blood loss greater than 500 mL after delivery compared to ergot alkaloids (RR 0.44, 95% CI 0.20 to 0.94; 1168 women; 3 studies; low-quality evidence), based on outcomes from quasi-randomised trials with a high risk of bias. There were no maternal deaths reported in either treatment group in the one trial that reported this outcome (RR not estimable; 1 trial, 807 women; moderate-quality evidence). Need for additional uterotonics was not reported.No subgroup differences were observed between active or expectant management, or different routes or doses of oxytocin for any of our comparisons.

AUTHORS' CONCLUSIONS

Prophylactic oxytocin compared with no uterotonics may reduce blood loss and the need for additional uterotonics. The effect of oxytocin compared to ergot alkaloids is uncertain with regards to blood loss, need for additional uterotonics, and blood transfusion. Oxytocin may increase the risk of a prolonged third stage compared to ergot alkaloids, although whether this translates into increased risk of manual placental removal is uncertain. This potential risk must be weighed against the possible increased risk of side effects associated with ergot alkaloids. Oxytocin-ergometrine may reduce blood loss compared to ergot alkaloids, however the certainty of this conclusion is low. More high-quality trials are needed to assess optimal dosing and route of oxytocin administration, with inclusion of important outcomes such as maternal mortality, shock, and transfer to a higher level of care. A network meta-analysis of uterotonics for PPH prevention plans to address issues around optimal dosing and routes of oxytocin and other uterotonics.

WITHDRAWN: Systemic treatments for metastatic cutaneous melanoma

BACKGROUND

Systemic therapies for metastatic cutaneous melanoma, the most aggressive of all skin cancers, remain disappointing. Few lasting remissions are achieved and the therapeutic aim remains one of palliation.Many agents are used alone or in combination with varying degrees of toxicity and cost. It is unclear whether evidence exists to support these complex regimens over best supportive care / placebo.

OBJECTIVES

To review the benefits from the use of systemic therapies in metastatic cutaneous melanoma compared to best supportive care/placebo, and to establish whether a 'standard' therapy exists which is superior to other treatments.

SEARCH METHODS

Randomised controlled trials were identified from the MEDLINE, EMBASE and CCTR/CENTRAL databases. References, conference proceedings, and Science Citation Index/Scisearch were also used to locate trials. Cancer registries and trialists were also contacted.

SELECTION CRITERIA

Randomised controlled trials of adults with histologically proven metastatic cutaneous melanoma in which systemic anti-cancer therapy was compared with placebo or supportive care.

DATA COLLECTION AND ANALYSIS

Study selection was performed by two independent reviewers. Data extraction forms were used for studies which appeared to meet the selection criteria and, where appropriate, full text articles were retrieved and reviewed independently.

MAIN RESULTS

No randomised controlled trials were found comparing a systemic therapy with placebo or best supportive care in metastatic cutaneous melanoma.

AUTHORS' CONCLUSIONS

There is no evidence from randomised controlled clinical trials to show superiority of systemic therapy over best supportive care / placebo in the treatment of malignant cutaneous melanoma.Given that patients with metastatic melanoma frequently receive systemic therapy, it is our pragmatic view that a future systematic review could compare any systemic treatment, or combination of treatments, to single agent dacarbazine.

Effect of co-administration of different doses of phenylephrine with oxytocin on the prevention of oxytocin-induced hypotension in caesarean section under spinal anaesthesia: A randomised comparative study

INTRODUCTION

Co-administration of phenylephrine prevents oxytocin-induced hypotension during caesarean section under spinal anaesthesia (SA), but higher doses cause reflex bradycardia. This study compares the effects of co-administration of two different doses of phenylephrine on oxytocin-induced hypotension during caesarean section under SA.

METHODS

In this prospective, double-blind study, 90 parturients belonging to the American Society of Anesthesiologists' physical status 1 or 2, undergoing caesarean section under SA were randomised into Group A: oxytocin 3U and phenylephrine 50 μg, Group B: oxytocin 3U and phenylephrine 75 μg, Group C: oxytocin 3U and normal saline, administered intravenously over 5 min after baby extraction. The incidence of hypotension (the primary outcome), rescue vasopressor requirement and side effects were recorded. Statistical analyses were with analysis of variance, Kruskal-Wallis, chi-square and Fisher's exact tests.

RESULTS

Demographic parameters such as age, height, weight, level of sensory block at 20 min and duration of surgery were comparable in all the groups. The incidence of hypotension (Group A - 90%, Group B - 10%, Group C - 98%, P = 0.001), magnitude of fall in mean arterial pressure (Group A-15.03 ± 6.12 mm of Hg, Group B - 6.63 ± 4.49 mm of Hg and Group C-13.03 ± 3.39 mm of Hg, P < 0.001) and rescue vasopressor requirement (Group A-45 ± 15.25 mg, Group B-5 ± 15.25, Group C-91.66 ± 26.53, P < 0.001) were significantly lower in Group B compared to A and C.

CONCLUSION

Co-administration of phenylephrine 75 μg with oxytocin 3U reduces the incidence of oxytocin-induced hypotension compared to phenylephrine 50 μg with oxytocin 3U during caesarean section under spinal anaesthesia.

Postpartum hemorrhage with pelvic arterial embolization, study of 33 cases

OBJECTIVE

To describe our cases of postpartum hemorrhage (PPH) with pelvic arterial embolization (PAE).

MATERIAL AND METHODS

All patients with PPH who underwent PAE in our center in the interval 2011-1016 were retrospectively studied, evaluating the technical procedure, clinical results, and subsequent fertility.

RESULTS

There were 33 cases of PPH with PAE. The majority occurred in primiparous women (N = 22, 66.6%) who delivered vaginally (N = 20, 61%). In addition, most PPH with PAE cases had an early onset (N = 26, 79%) and were caused by uterine atony (N = 14, 42.4%). Success of PAE occurred in 27 (81.8%) cases and a satisfactory clinical follow-up was the rule, with 21 (64%) women recovering their normal menstruation, and six (18.2%) becoming pregnant in the following years.

CONCLUSIONS

PAE is a safe and efficacious technique with minor complications. Moreover, it allows conservation of the uterus with preservation of fertility.

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.

WITHDRAWN: Day care for pre-school children

BACKGROUND

The debate about how, where and by whom young children should be looked after is one which has occupied much social policy and media attention in recent years. Mothers undertake most of the care of young children. Internationally, out-of-home day-care provision ranges widely. These different levels of provision are not simply a response to different levels of demand for day-care, but reflect cultural and economic interests concerning the welfare of children, the need to promote mothers' participation in paid work, and the importance of socialising children into society's values. At a time when a decline in family values is held responsible for a range of social problems, the day-care debate has a special prominence.

OBJECTIVES

To quantify the effects of out-of-home day-care for preschool children on educational, health and welfare outcomes for children and their families.

SEARCH METHODS

Randomised controlled trials of day-care for pre-school children were identified using electronic databases, hand searches of relevant literature, and contact with authors.

SELECTION CRITERIA

Studies were included in the review if the intervention involved the provision of non-parental day care for children under 5 years of age, and the evaluation design was that of a randomised or quasi-randomised controlled trial.

DATA COLLECTION AND ANALYSIS

A total of eight trials were identified after examining 920 abstracts and 19 books. The trials were assessed for methodological quality.

MAIN RESULTS

Day-care increases children's IQ, and has beneficial effects on behavioural development and school achievement. Long-term follow up demonstrates increased employment, lower teenage pregnancy rates, higher socio-economic status and decreased criminal behaviour. There are positive effects on mothers' education, employment and interaction with children. Effects on fathers have not been examined. Few studies look at a range of outcomes spanning the health, education and welfare domains. Most of the trials combined non-parental day-care with some element of parent training or education (mostly targeted at mothers); they did not disentangle the possible effects of these two interventions. The trials had other significant methodological weaknesses, pointing to the importance of improving on study design in this field. All the trials were carried out in the USA.

AUTHORS' CONCLUSIONS

Day care has beneficial effect on children's development, school success and adult life patterns. To date, all randomised trials have been conducted among disadvantaged populations in the USA. The extent to which the results are generaliseable to other cultures and socioeconomic groups has yet to be evaluated.

Replacement of oxytocin bolus administration by infusion: influences on postpartum outcome

PURPOSE

Postpartum haemorrhage (PPH) represents a leading cause of maternal morbidity and mortality. Giving oxytocin after birth reduces the risk for PPH. It has never been tested whether different methods of oxytocin administration affect the maternal outcome. This study aims to compare the infusion versus the bolus application of oxytocin after singleton vaginal delivery.

METHODS

This retrospective monocentre study compares the incidence of clinically relevant postpartum complications in women receiving 5 IE of oxytocin as a bolus or as a 100 ml-infusion over 5 min, given immediately after birth. Included were women delivering singletons vaginally at term. We used propensity score weighting to compare outcomes between women receiving bolus and infusion and to minimize the selection bias in this retrospective cohort.

RESULTS

1765 patients were included. Patient characteristics were balanced. We found no significant differences for the combined overall postpartum adverse outcome (the incidence of PPH, manual removal of the placenta and/or curettage). For the single outcomes, we observed a significantly higher frequency of manual removal of the placenta (Odds ratio 1.47, 95 % CI 1.02-2.13) and a slightly higher but clinically not relevant estimated blood loss (Relative effect 1.05, 95 % CI 1.01-1.10) in the infusion group.

CONCLUSION

The data show a tendency towards more complications in the infusion group. It is related to a more frequent need for manual removal of the placenta.

A Randomized, Double-blinded Trial of a "Rule of Threes" Algorithm versus Continuous Infusion of Oxytocin during Elective Cesarean Delivery

BACKGROUND

The administration of uterotonic agents during cesarean delivery is highly variable. The authors hypothesized a "rule of threes" algorithm, featuring oxytocin 3 IU, timed uterine tone evaluations, and a systematic approach to alternative uterotonic agents, would reduce the oxytocin dose required to obtain adequate uterine tone.

METHODS

Sixty women undergoing elective cesarean delivery were randomized to receive a low-dose bolus or continuous infusion of oxytocin. To blind participants, the rule group simultaneously received intravenous oxytocin (3 IU/3 ml) and a "wide-open" infusion of 0.9% normal saline (500 ml); the standard care group received intravenous 0.9% normal saline (3 ml) and a "wide-open" infusion of oxytocin (30 IU in 0.9% normal saline/500 ml). Uterine tone was assessed at 3, 6, 9, and 12 min, and if inadequate, additional uterotonic agents were administered. Uterine tone, total dose and timing of uterotonic agent use, maternal hemodynamics, side effects, and blood loss were recorded.

RESULTS

Adequate uterine tone was achieved with lower oxytocin doses in the rule versus standard care group (mean, 4.0 vs. 8.4 IU; point estimate of the difference, 4.4 ± 1.0 IU; 95% CI, 2.60 to 6.15; P < 0.0001). No additional oxytocin or alternative uterotonic agents were needed in either group after 6 min. No differences in the uterine tone, maternal hemodynamics, side effects, or blood loss were observed.

CONCLUSION

A "rule of threes" algorithm using oxytocin 3 IU results in lower oxytocin doses when compared with continuous-infusion oxytocin in women undergoing elective cesarean delivery.

Progress in understanding electro-mechanical signalling in the myometrium

In this review, we give a state-of-the-art account of uterine contractility, focussing on excitation-contraction (electro-mechanical) coupling (ECC). This will show how electrophysiological data and intracellular calcium measurements can be related to more modern techniques such as confocal microscopy and molecular biology, to advance our understanding of mechanical output and its modulation in the smooth muscle of the uterus, the myometrium. This new knowledge and understanding, for example concerning the role of the sarcoplasmic reticulum (SR), or stretch-activated K channels, when linked to biochemical and molecular pathways, provides a clearer and better informed basis for the development of new drugs and targets. These are urgently needed to combat dysfunctions in excitation-contraction coupling that are clinically challenging, such as preterm labour, slow to progress labours and post-partum haemorrhage. It remains the case that scientific progress still needs to be made in areas such as pacemaking and understanding interactions between the uterine environment and ion channel activity.

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.

Prophylactic oxytocin for the third stage of labour to prevent postpartum haemorrhage

BACKGROUND

Active management of the third stage of labour has been shown to reduce the risk of postpartum haemorrhage (PPH) greater than 1000 mL. One aspect of the active management protocol is the administration of prophylactic uterotonics, however, the type of uterotonic, dose, and route of administration vary across the globe and may have an impact on maternal outcomes.

OBJECTIVES

To determine the effectiveness of prophylactic oxytocin at any dose to prevent PPH and other adverse maternal outcomes related to the third stage of labour.

SEARCH METHODS

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

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials including pregnant women anticipating a vaginal delivery where prophylactic oxytocin was given during management of the third stage of labour. The primary outcomes were blood loss > 500 mL and the use of therapeutic uterotonics.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion, assessed trial quality and extracted data. Data were checked for accuracy.

MAIN RESULTS

This updated review included 20 trials (involving 10,806 women). Prophylactic oxytocin versus placebo Prophylactic oxytocin compared with placebo reduced the risk of PPH greater than 500 mL, (risk ratio (RR) 0.53; 95% confidence interval (CI) 0.38 to 0.74; six trials, 4203 women; T² = 0.11, I² = 78%) and the need for therapeutic uterotonics (RR 0.56; 95% CI 0.36 to 0.87, four trials, 3174 women; T² = 0.10, I² = 58%). The benefit of prophylactic oxytocin to prevent PPH greater than 500 mL was seen in all subgroups. Decreased use of therapeutic uterotonics was only seen in the following subgroups: randomised trials with low risk of bias (RR 0.58; 95% CI 0.36 to 0.92; three trials, 3122 women; T² = 0.11, I² = 69%); trials that performed active management of the third stage (RR 0.39; 95% CI 0.26 to 0.58; one trial, 1901 women; heterogeneity not applicable); trials that delivered oxytocin as an IV bolus (RR 0.57; 95% CI 0.39 to 0.82; one trial, 1000 women; heterogeneity not applicable); and in trials that gave oxytocin at a dose of 10 IU (RR 0.48; 95% CI 0.33 to 0.68; two trials, 2901 women; T² = 0.02, I² = 27%). Prophylactic oxytocin versus ergot alkaloids. Prophylactic oxytocin was superior to ergot alkaloids in preventing PPH greater than 500 mL (RR 0.76; 95% CI 0.61 to 0.94; five trials, 2226 women; T² = 0.00, I² = 0%). The benefit of oxytocin over ergot alkaloids to prevent PPH greater than 500 mL only persisted in the subgroups of quasi-randomised trials (RR 0.71, 95% CI 0.53 to 0.96; three trials, 1402 women; T² = 0.00, I² = 0%) and in trials that performed active management of the third stage of labour (RR 0.58; 95% CI 0.38 to 0.89; two trials, 943 women; T² = 0.00, I² = 0%). Use of prophylactic oxytocin was associated with fewer side effects compared with use of ergot alkaloids; including decreased nausea between delivery of the baby and discharge from the labour ward (RR 0.18; 95% CI 0.06 to 0.53; three trials, 1091 women; T² = 0.41, I² = 41%) and vomiting between delivery of the baby and discharge from the labour ward (RR 0.07; 95% CI 0.02 to 0.25; three trials, 1091 women; T² = 0.45, I² = 30%). Prophylactic oxytocin + ergometrine versus ergot alkaloids: There was no benefit seen in the combination of oxytocin and ergometrine versus ergometrine alone in preventing PPH greater than 500 mL (RR 0.90; 95% CI 0.34 to 2.41; five trials, 2891 women; T² = 0.89, I² = 80%). The use of oxytocin and ergometrine was associated with increased mean blood loss (MD 61.0 mL; 95% CI 6.00 to 116.00 mL; fixed-effect analysis; one trial, 34 women; heterogeneity not applicable).In all three comparisons, there was no difference in mean length of the third stage or need for manual removal of the placenta between treatment arms.

AUTHORS' CONCLUSIONS

Prophylactic oxytocin at any dose decreases both PPH greater than 500 mL and the need for therapeutic uterotonics compared to placebo alone. Taking into account the subgroup analyses from both primary outcomes, to achieve maximal benefit providers may opt to implement a practice of giving prophylactic oxytocin as part of the active management of the third stage of labour at a dose of 10 IU given as an IV bolus. If IV delivery is not possible, IM delivery may be used as this route of delivery did show a benefit to prevent PPH greater than 500 mL and there was a trend to decrease the need for therapeutic uterotonics, albeit not statistically significant.Prophylactic oxytocin was superior to ergot alkaloids in preventing PPH greater than 500 mL; however, in subgroup analysis this benefit did not persist when only randomised trials with low risk of methodologic bias were analysed. Based on this, there is limited high-quality evidence supporting a benefit of prophylactic oxytocin over ergot alkaloids. However, the use of prophylactic oxytocin was associated with fewer side effects, specifically nausea and vomiting, making oxytocin the more desirable option for routine use to prevent PPH.There is no evidence of benefit when adding oxytocin to ergometrine compared to ergot alkaloids alone, and there may even be increased harm as one study showed evidence that using the combination was associated with increased mean blood loss compared to ergot alkaloids alone.Importantly, there is no evidence to suggest that prophylactic oxytocin increases the risk of retained placenta when compared to placebo or ergot alkaloids.More placebo-controlled, randomised, and double-blinded trials are needed to improve the quality of data used to evaluate the effective dose, timing, and route of administration of prophylactic oxytocin to prevent PPH. In addition, more trials are needed especially, but not only, in low- and middle-income countries to evaluate these interventions in the birth centres that shoulder the majority of the burden of PPH in order to improve maternal morbidity and mortality worldwide.

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.

Survey of prophylactic use of uterotonics in the third stage of labour in the Netherlands

OBJECTIVE

aim of this study was to investigate current knowledge and practice regarding AMTSL in midwifery practices and obstetric departments in the Netherlands.

DESIGN

web-based and postal questionnaire.

SETTING

in August and September 2011 a questionnaire was sent to all midwifery practices and all obstetric departments in the Netherlands.

PARTICIPANTS

all midwifery practices (528) and all obstetric departments (91) in the Netherlands.

MEASUREMENTS AND FINDINGS

the response was 87.5%. Administering prophylactic uterotonics was seen as a component AMTSL by virtually all respondents; 96.1% of midwives and 98.8% of obstetricians. Cord clamping was found as a component of AMTSL by 87.4% of midwives and by 88.1% of obstetricians. Uterine massage was only seen as a component of AMTSL by 10% of the midwives and 20.2% of the obstetricians. Midwifery practices routinely administer oxytocin in 60.1% of births. Obstetric departments do so in 97.6% (p<0.01). Compared to 1995, the prophylactic use of oxytocin had increased in 2011 both by midwives (10-59.1%) and by obstetricians (55-96.4%) (p<0.01).

KEY CONCLUSIONS

prophylactic administration of uterotonics directly after childbirth is perceived as the essential part of AMTSL. The administration of uterotonics has significantly increased in the last decade, but is not standard practice in the low-risk population supervised by midwives.

IMPLICATIONS FOR PRACTICE

the evidence for prophylactic administration of uterotonics is convincing for women who are at high risk of PPH. Regarding the lack of evidence of AMTSL to prevent PPH in low risk (home) births, further research concerning low-risk (home) births, supervised by midwives in industrialised countries is indicated. A national guideline containing best practices concerning management of the third stage of labour supervised by midwives, should be composed and implemented.

Use of oxytocin during early stages of labor and its effect on active management of third stage of labor

OBJECTIVE

The purpose of this study was to evaluate whether the use of oxytocin during the first and second stages of labor is associated with a higher incidence of postpartum hemorrhage (PPH) in pregnant women who received active management of third stage of labor (AMTSL).

STUDY DESIGN

A secondary data analysis from vaginal deliveries in a hospital-based cohort study from 24 maternity hospitals in South America. The primary outcomes that were analyzed were moderate PPH (≥500 mL of blood loss), severe PPH (≥1000 mL of blood loss), and need of blood transfusion.

RESULTS

A total of 11,323 vaginal deliveries were included. The incidence of moderate and severe PPH was 10.8% and 1.86%, respectively. Overall, 36% of deliveries received AMTSL. There was no association between induced/augmented labor and moderate PPH (P = .753), severe PPH (P = .273), and blood transfusion (P = .603) in the population that received AMTSL.

CONCLUSION

AMTSL should be recommended, regardless of whether pregnant women received oxytocin during the first and second stages of labor.

Carbetocin for the prevention of postpartum hemorrhage: a systematic review

The objective of this review was to evaluate the efficacy and safety of carbetocin in the prevention of postpartum hemorrhage. All trials found during a targeted Medline and Cochrane database search were screened for eligibility. Outcome measures were estimated blood loss, uterine tone, amount and type of lochia, fundal position after delivery (number of centimeters above or below the umbilicus), side-effects, adverse effects, vital signs, levels of hemoglobin/hematocrit before delivery compared with 24 or 48 hours postpartum, the need for additional uterotonic therapy, and/or uterine massage and duration of the third stage of labor. The retrieved studies were difficult to compare because of differences in study design and outcome. We conclude that carbetocin probably is as effective as oxytocin or syntometrine in the prophylactic management of the third stage of labor. Also carbetocin has a similar safety profile to oxytocin, which is now used as a standard prophylactic treatment. However, more research on this subject is needed.

How do physicians and midwives manage the third stage of labor?

BACKGROUND

Current practice guidelines recommend active management of the third stage of labor. We compared practices of three maternity care provider disciplines in management of third-stage labor and the justifications for their approach.

METHODS

This study is a cross-sectional survey of maternity practitioners in usual practice settings in British Columbia. All 199 obstetricians, all 82 midwives, and a random sample of family physicians practicing intrapartum maternity care (one-third, or 346) were surveyed The three main outcome measures by discipline were the method preferred in managing third-stage labor, the reasons given for the chosen method, and views on the appropriateness of the current third-stage labor guideline.

RESULTS

The overall response rate was 57.8 percent. Response rates indicating that the participants were "aware of guideline" were the following: obstetricians, 85.3 percent; family physicians, 53.7 percent; and midwives, 97.8 percent. Response rates indicating that the participants "agreed with guideline" were the following: obstetricians, 95.2 percent; family physicians, 97.6 percent; and midwives, 51.2 percent. Response rates indicating that "oxytocin should be given with anterior shoulder" were the following: obstetricians, 71.1 percent; family physicians, 68.3 percent; and midwives, 26.7 percent. Response rates indicating that "routine active management of third stage of labor should be the norm" were the following: obstetricians, 79.2 percent; family physicians, 60.2 percent; and midwives, 17 percent. All results were statistically significant (p < 0.01).

CONCLUSIONS

A major difference was found between physicians and midwives in the management of third-stage labor. Physicians routinely implemented active management of the third stage of labor; midwives preferred expectant approaches, principally based on women's preference. Provincial data did not show differences in postpartum hemorrhage or transfusion rates by practitioner type.

Rectal Misoprostol Versus Oxytocin in the Management of the Third Stage of Labour

OBJECTIVE

To compare the effect of rectal misoprostol with intramuscular oxytocin in the routine management of the third stage in a rural developing country.

METHODS

A randomized controlled trial was performed at two district hospitals in Ghana, West Africa. Four hundred fifty women in advanced labour were enrolled. The only exclusion criterion was a known medical contraindication to prostaglandin administration. Women were randomized to receive rectal misoprostol 800 microg or intramuscular oxytocin 10 IU with delivery of the anterior shoulder. The main outcome measure was change in hemoglobin concentration from before to after delivery. Secondary outcomes included the need for additional uterotonics, estimated blood loss, transfusion, and medication side effects.

RESULTS

Demographic characteristics were similar in each treatment group. There was no significant difference between treatment groups in change in hemoglobin (misoprostol 1.19 g/dL and oxytocin 1.16 g/dL; relative difference 2.6%; 95% confidence intervals [CI]-16.8% to 19.4%; P = 0.80). The only significant secondary outcome was shivering, which was more common in the misoprostol group (misoprostol 7.5% vs. oxytocin 0.9%; relative risk 8.0; 95% CI 1.86-34.36; P = 0.001).

CONCLUSION

Rectal misoprostol 800 microg is as effective as 10 IU intramuscular oxytocin in minimizing blood loss in the third stage of labour. Rectal misoprostol has a lower incidence of side effects than the equivalent oral dose. This confirms the utility of misoprostol as a safe and effective uterotonic for use in the rural and remote areas of developing nations where other pharmacologic agents may be less feasible.

Prospective study of intramuscular ergometrine compared with intramuscular oxytocin for prevention of postpartum hemorrhage

AIM

To compare the efficacy and safety of intramuscular oxytocin with intramuscular ergometrine in the management of postpartum hemorrhage during the third stage of labor.

METHODS

Women who had been pregnant for more than 35 weeks and delivered cephalic singletons vaginally without predelivery administration of oxytocics were included. The cases considered to be at high risk were excluded, such as those who had uterine fibroids, a previous cesarean section, previous postpartum hemorrhage, or severe anemia. Five units of oxytocin or 0.2 mg of methylergometrine were administered intramuscularly immediately after delivery of the baby.

RESULTS

Compared with intramuscular ergometrine, the use of intramuscular oxytocin was associated with a significant reduction in mean total postpartum blood loss (288.16 g vs 354.42 g, P = 0.004), frequency of postpartum hemorrhage (> or=500 mL: 10.9% vs 20.32%, relative risk [RR] = 0.54, 95% confidence interval [CI] = 0.32-0.91), and need for therapeutic oxytocics (5.13% vs 12.3%, RR = 0.42, 95% CI = 0.19-0.91). There were no differences between the groups in terms of the mean duration of the third stage, the mean level of hemoglobin on the second postpartum day, and the frequency of postpartum hemorrhage (> or =1000 mL), or manual removal of placenta. Few side-effects were found, with no significant differences between the groups.

CONCLUSIONS

The routine use of intramuscular oxytocin is more effective than the use of intramuscular ergometrine for prevention of postpartum hemorrhage in the third stage of labor.

A randomised trial of carbetocin versus syntometrine in the management of the third stage of labour

OBJECTIVE

Syntometrine is an effective uterotonic agent used in preventing primary postpartum haemorrhage but has adverse effects including nausea, vomiting, hypertension and coronary artery spasm. Carbetocin is a newly developed long-acting oxytocin analogue that might be used as an uterotonic agent. We compare the efficacy and safety of intramuscular (IM) carbetocin with IM syntometrine in preventing primary postpartum haemorrhage.

DESIGN

Prospective, double-blinded, randomised controlled trial.

SETTING

Delivery suite of a university-based obstetrics unit.

POPULATION

Women with singleton pregnancy achieving vaginal delivery after and throughout 34 weeks.

METHODS

Three hundred and twenty-nine eligible women were randomised to receive either a single dose of 100 microgram IM carbetocin or 1 ml IM syntometrine (a mixture of 5 iu oxytocin and 0.5 mg ergometrine) at the end of second stage of labour.

MAIN OUTCOME MEASURES

Difference in haemoglobin drop measured 2 days after delivery between the two groups.

RESULTS

There was no difference in the drop of haemoglobin concentration within the first 48 hours between the two groups. The incidence of additional oxytocic injections, postpartum haemorrhage (blood loss > or = 500 ml) and retained placenta were also similar. The use of carbetocin was associated with significant lower incidence of nausea (relative risk [RR] 0.18, 95% confidence interval [CI] 0.04-0.78), vomiting (RR 0.1, 95% CI 0.01-0.74), hypertension 30 minutes (0 versus 8 cases, P < 0.01) and 60 minutes (0 versus 6 cases, P < 0.05) after delivery but a higher incidence of maternal tachycardia (RR 1.68, 95% CI 1.03-3.57).

CONCLUSIONS

IM carbetocin is as effective as IM syntometrine in preventing primary postpartum haemorrhage after vaginal delivery. It is less likely to induce hypertension and has a low incidence of adverse effect. It should be considered as a good alternative to conventional uterotonic agents used in managing the third stage of labour.

Puerperal uterine inversion: A report of four cases

Acute puerperal uterine inversion is a life-threatening and unpredictable obstetric emergency. If overlooked, it could lead to a maternal death. Although the precise cause is unknown, it is postulated to be caused by the mismanagement of the third stage of labor with premature traction of the umbilical cord and fundal pressure before placental separation. At the Ipoh General Hospital in Malaysia there were 31 394 deliveries and four acute uterine inversions occurring from 1 January 2002 to 30 June 2005. The four patients were between 25 and 36 years of age and their parities were between two and three. When manual repositioning of the uterus failed, successful correction was accomplished by the O'Sullivan's hydrostatic method. One case had to undergo subtotal hysterectomy after repositioning because of massive hemorrhage secondary to placenta accreta. Early diagnosis, immediate treatment of shock, and replacement are essential.

Minimum Oxytocin Dose Requirement After Cesarean Delivery for Labor Arrest

OBJECTIVE

To estimate the minimum effective intravenous dose of oxytocin required for adequate uterine contraction after cesarean delivery for labor arrest.

METHODS

A randomized single-blinded study was undertaken in 30 parturients undergoing cesarean deliveries under epidural anesthesia for labor arrest despite intravenous oxytocin augmentation. Oxytocin was administered as a slow intravenous bolus immediately after delivery of the infant, according to a biased coin up-down sequential allocation scheme. After assisted spontaneous delivery of the placenta, the obstetrician, blinded to the oxytocin dose, assessed uterine contraction as either satisfactory or unsatisfactory. Additional boluses of oxytocin were administered as required, followed by a maintenance infusion. Data were interpreted and analyzed by a logistic regression model at 95% confidence intervals.

RESULTS

All patients received oxytocin infusions at a mean +/- standard deviation of 9.8 +/- 6.3 hours before cesarean delivery (maximum infusion dose 10.3 +/- 8.2 mU/min). The minimum effective dose of oxytocin required to produce adequate uterine response in 90% of women (ED90) was estimated to be 2.99 IU (95% confidence interval 2.32-3.67). The estimated blood loss was 1,178 +/- 716 mL.

CONCLUSION

Women requiring cesarean delivery for labor arrest after oxytocin augmentation require approximately 3 IU rapid intravenous infusion of oxytocin to achieve effective uterine contraction after delivery. This dose is 9 times more than previously reported after elective cesarean delivery in nonlaboring women at term, suggesting oxytocin receptor desensitization from exogenous oxytocin administration during labor. Therefore, alternative uterotonic agents, rather than additional oxytocin, may achieve superior uterine contraction and control of blood loss during cesarean delivery for labor arrest.

LEVEL OF EVIDENCE

I.

Oral Misoprostol Versus Oxytocin in the Management of the Third Stage of Labour

OBJECTIVE

To compare the effects of oral misoprostol 800 mug with intramuscular oxytocin 10 IU in routine management of the third stage of labour.

METHODS

This randomized controlled trial was performed in a rural district hospital in Ghana, West Africa, and enrolled women in labour with anticipated vaginal delivery and no known medical contraindication to prostaglandin administration. Women were randomized to receive oral misoprostol 800 mug or intramuscular oxytocin 10 IU. Blood samples were taken to determine hemoglobin concentration before delivery and at 12 hours post partum. Treatment was administered at delivery of the anterior shoulder. The primary outcome was the change in hemoglobin concentration from before to after delivery. Secondary outcomes included other measures of blood loss and presumed medication side effects.

RESULTS

In total, 450 women were enrolled in the study. Their baseline characteristics were similar. There was no significant difference between the groups in the change in hemoglobin concentration (misoprostol 1.07 g/dL and oxytocin 1.00 g/dL). The only significant secondary outcomes were shivering (80.7% with misoprostol vs. 3.6% with oxytocin) and pyrexia (11.4% with misoprostol, none with oxytocin).

CONCLUSION

Routine use of oral misoprostol 800 microg appears to be as effective as 10 IU parenteral oxytocin in minimizing blood loss during the third stage of labour, as determined by change in hemoglobin concentration. Misoprostol appears to be a safe, inexpensive, and effective uterotonic for use in rural and remote areas, where intravenous oxytocin may be unavailable.

Oral misoprostol in the third stage of labor

OBJECTIVE

To compare the efficacy of intravenous ergometrine, intramuscular oxytocin, and oral misoprostol in the control of postpartum hemorrhage.

METHODS

Mean blood loss, rates of blood loss between 500 and 1000 ml, hematocrit fall greater than 10%, and need for additional oxytocic agents and nature and rates of adverse effects were assessed in this prospective, randomized, controlled study.

RESULTS

All outcomes were similar in the 3 groups. The main adverse effects in the misoprostol group were temperatures higher than 99 degrees F, which normalized within 2 h and shivering, which was mild and self-limiting.

CONCLUSIONS

Oral misoprostol is as effective as conventional oxytocic agents in preventing postpartum hemorrhage and can be recommended for use in low-resource settings.

Maternal Hemodynamics After Oxytocin Bolus Compared With Infusion in the Third Stage of Labor: A Randomized Controlled Trial

OBJECTIVE

To assess the effects of oxytocin bolus or infusion on maternal hemodynamics in the third stage of labor.

METHODS

In a randomized, double-blind, double-dummy fashion, 99 women received an intravenous oxytocin bolus (10 IU push) and 102 women received an infusion (10 IU in 500 mL saline at 125 mL/h) at delivery of the anterior shoulder. Mean arterial pressure and heart rate were measured every minute for 10 minutes, then every 5 minutes for the next 20 minutes. These serial measurements were analyzed using a 2-factor analysis of variance for repeated measures.

RESULTS

Serial mean arterial pressure measures varied significantly between groups (interaction effect, P = .002). Mean arterial pressure (+/- standard deviation) nadirs were reached after 10 minutes, 80.9 (+/- 11.0) mm Hg in the bolus group compared with 77.0 (+/- 12.1) mm Hg in the dilute infusion group. The mean difference (95% confidence interval) between groups was 4.0 (0.7-7.2) mm Hg. Serial heart rate measures also varied between groups (interaction effect, P < .001). Mean heart rate (+/- standard deviation) peaked 1 minute after the oxytocin infusion, 115 (+/- 27) beats per minute (bpm) in the bolus group compared with 109 (+/- 21) bpm in the dilute infusion group. The mean difference (95% confidence interval) between groups was 6.6 bpm (-0.1 to 13.3). The dilute oxytocin infusion group experienced a greater mean estimated blood loss (423.7 mL compared with 358.1 mL, P = .029, t test), increased use of additional oxytocics (35.3% compared with 22.2%, P = .044, Fisher exact test) and a greater drop in hemoglobin (admission minus postpartum) (17.4g/L compared with 11.4g/L, P = .002, t test) compared with the oxytocin bolus group.

CONCLUSION

Bolus oxytocin of 10 IU is not associated with adverse hemodynamic responses and can safely be administered to women with intravenous access in the third stage of labor for postpartum hemorrhage prophylaxis.

LEVEL OF EVIDENCE

I.

Buccal Misoprostol to Decrease Blood Loss After Vaginal Delivery: A Randomized Trial

OBJECTIVE

To assess the efficacy of buccal misoprostol to decrease bleeding after vaginal delivery.

METHODS

This was a randomized study of patients between 22 weeks and 42 weeks of gestation with anticipated vaginal delivery. Patients were given either a 200-mug misoprostol tablet or placebo in the buccal space at the time of cord clamping. A continuous dilute intravenous oxytocin infusion was given to all patients at delivery of the placenta. Postpartum hemorrhage was defined as blood loss exceeding 500 mL. Sample size calculations based on previous studies assumed a 13% incidence of postpartum hemorrhage in the control group. To show a statistically significant reduction of postpartum hemorrhage a total of 1,604 patients would be required in each group.

RESULTS

A total of 848 patients were enrolled and 756 randomly assigned, 377 in the misoprostol group and 379 in the placebo group. Demographic, antepartum, and intrapartum characteristics were similar between the groups. The incidence of postpartum hemorrhage, 3% compared with 5%, (relative risk 0.65, 95% confidence interval 0.33-1.29, P = .22), mean estimated blood loss, 322 compared with 329 mL, (P = .45), and mean minutes of the third stage of labor, 6.7 compared with 6.9 (P = .52) were similar between the groups, misoprostol and placebo, respectively. Hemoglobin difference before and after delivery, need for second or third uterotonic agent, and all measured neonatal variables including birth weights, and umbilical cord pH were similar between the groups.

CONCLUSION

Buccal misoprostol at cord clamping is no more effective than placebo in reducing postpartum hemorrhage.

A systematic review of the content of critical appraisal tools

Background

Consumers of research (researchers, administrators, educators and clinicians) frequently use standard critical appraisal tools to evaluate the quality of published research reports. However, there is no consensus regarding the most appropriate critical appraisal tool for allied health research. We summarized the content, intent, construction and psychometric properties of published, currently available critical appraisal tools to identify common elements and their relevance to allied health research.

Methods

A systematic review was undertaken of 121 published critical appraisal tools sourced from 108 papers located on electronic databases and the Internet. The tools were classified according to the study design for which they were intended. Their items were then classified into one of 12 criteria based on their intent. Commonly occurring items were identified. The empirical basis for construction of the tool, the method by which overall quality of the study was established, the psychometric properties of the critical appraisal tools and whether guidelines were provided for their use were also recorded.

Results

Eighty-seven percent of critical appraisal tools were specific to a research design, with most tools having been developed for experimental studies. There was considerable variability in items contained in the critical appraisal tools. Twelve percent of available tools were developed using specified empirical research. Forty-nine percent of the critical appraisal tools summarized the quality appraisal into a numeric summary score. Few critical appraisal tools had documented evidence of validity of their items, or reliability of use. Guidelines regarding administration of the tools were provided in 43% of cases.

Conclusions

There was considerable variability in intent, components, construction and psychometric properties of published critical appraisal tools for research reports. There is no "gold standard' critical appraisal tool for any study design, nor is there any widely accepted generic tool that can be applied equally well across study types. No tool was specific to allied health research requirements. Thus interpretation of critical appraisal of research reports currently needs to be considered in light of the properties and intent of the critical appraisal tool chosen for the task.

Comparison of Carbetocin and Oxytocin for the Prevention of Postpartum Hemorrhage Following Vaginal Delivery: A Double-Blind Randomized Trial

OBJECTIVES

To compare the efficacy of a single 100 micro g intramuscular (IM) carbetocin injection, a long-acting oxytocin agonist, to a 2-hour 10 IU oxytocin intravenous (IV) infusion, in reducing the incidence and severity of postpartum hemorrhage (PPH) in women at risk for this condition.

METHODS

A randomized, double-blind, placebo-controlled study was conducted at 2 hospital centres, including 160 women with at least 1 risk factor for PPH. Eighty-three women received 100 microg carbetocin IM and an IV placebo immediately after placental delivery, while 77 women received placebo IM and oxytocin IV infusion. Complete blood count was collected at entry and 24 hours postpartum. All outcome measures, including the need for additional uterotonic agents or uterine massage, blood loss, and drop in hemoglobin and hematocrit, were analyzed using chi-square, Fisher exact, and Student t tests.

RESULTS

Population profile and risk factors for PPH were similar for each group. No significant difference was observed in the number of women requiring additional uterotonic medication (12 in each group). However, in the carbetocin group, 36 of the 83 women (43.4%) required at least 1 uterine massage compared to 48 of the 77 women (62.3%) in the oxytocin group (P <.02). Overall, uterotonic intervention was clinically indicated in 37 of the women (44.6%) receiving carbetocin compared to 49 of the women (63.6%) given an IV oxytocin infusion (P <.02). There were no differences in laboratory PPH indicators between the 2 groups.

A double-blinded, randomized controlled trial of oxytocin at the beginning versus the end of the third stage of labor for prevention of postpartum hemorrhage

OBJECTIVE

The objective of this study was to compare the administration of oxytocin at the beginning and end of the third stage of labor for the prevention of postpartum hemorrhage.

METHODS

Patients with documented singleton pregnancies were randomly assigned to two groups. The first received 10 units of oxytocin intramuscularly at delivery of the anterior shoulder of the fetus and an identical appearing placebo injection following delivery of the placenta. The second received the opposite medication sequence. The study was double blinded. Blood loss was measured by weighing all fluids collected, visual estimation, and serial blood counts.

RESULTS

27 women received oxytocin at the delivery of the fetal shoulder and 24 after the placenta. Oxytocin given after placenta delivery resulted in lower blood loss (345 vs. 400 ml, p = 0.28), lower collection bag weight (763 vs. 833 g, p = 0.55), lower change in HgB (-1.26 vs. -1.32 g, p = 0.86), lower DeltaHCT (-3.43 vs. -3.64%, p = 0.85), and a shorter third stage of labor duration (8.6 vs. 9.2 min, p = 0.75). The incidence of postpartum hemorrhage, defined as estimated blood loss >500 ml (0 vs. 14.8%) was significantly lowered with oxytocin following placental delivery (p = 0.049).

CONCLUSIONS

In our study, postpartum hemorrhage was less frequent when oxytocin administration was delayed until after placenta delivery.

Current strategies for the prevention of postpartum haemorrhage in the third stage of labour

PURPOSE OF REVIEW

Despite evidence that active management of the third stage of labour reduces the incidence of postpartum haemorrhage, expectant management is still widely practised. Factors accounting for this situation include the desire for a more natural experience of childbirth, the philosophy that active management is unnecessary in low-risk women, and avoidance of the adverse effects of conventional uterotonic agents. This review will evaluate the various strategies currently used for the prevention of primary postpartum haemorrhage.

RECENT FINDINGS

Since publication of the first systematic review comparing active with expectant management in 1988, active management of the third stage using oxytocics has become increasingly adopted. Recent surveys, however, show that there are still wide variations in practice around the world. Recent interest has focused on the use of misoprostol for the prevention of postpartum haemorrhage. Carbetocin, an oxytocin receptor agonist, shows promise but has not been evaluated for use after vaginal births.

SUMMARY

Active management of the third stage of labour is superior to expectant management in terms of blood loss, postpartum haemorrhage and other serious complications, but is associated with unpleasant side effects and hypertension when ergometrine is included. Intramuscular oxytocin results in fewer side effects. Oral and rectal misoprostol has been extensively assessed and found to be less effective than conventional oxytocics with more side effects. Until alternative regimes of misoprostol are studied in large controlled trials, misoprostol is not recommended for routine use in the third stage of labour. Of the remaining uterotonic agents evaluated, intramuscular carbetocin appears the most promising.

Massive obstetric hemorrhage

Massive obstetric haemorrhage is a major cause of maternal death and morbidity; abruption of the placenta, placenta praevia and postpartum haemorrhage being the main causes of haemorrhages. A delay in the correction of hypovolaemia, diagnosis and treatment of defective coagulation and/or surgical control of bleeding are the avoidable factors in most maternal deaths caused by haemorrhage. The main goal is to maintain effective circulating intravascular volume by prompt and adequate replacement of blood, crystalloids or fresh-frozen plasma through more than one intravenous line (it might be necessary to pump blood under pressure) with constant monitoring of the pulse rate and the arterial blood pressure. The rapid correction of hypovolaemia with crystalloids and red cells is the first priority, followed by blood component therapy. Oxytocin and prostaglandin will correct uterine atony, and appropriate surgical intervention is required for traumatic bleeding. Ligation of the uterine arteries, ovarian arteries and hypogastric arteries will usually control uterine bleeding and arterial embolization is also effective. Hysterectomy should also be considered in severe cases. All gynecologists should be able to perform without delay the operative maneuvers which are necessary to control the bleeding, including hypogastric artery ligation, or even emergency hysterectomy. This topic may have received little attention because it is perceived as being associated with maternal morbidity rather than mortality in developed countries; it is only recently that the extent and importance of postnatal maternal morbidity has been recognized.

Misoprostol use during the third stage of labor

OBJECTIVES

To systematically review the efficacy of misoprostol compared with placebo or other uterotonics in preventing maternal morbidity associated with the third stage of labor.

METHODS

We identified, retrieved, evaluated, abstracted data, and assessed the quality of all published studies (from January 1996 to May 2002) which assessed misoprostol's efficacy in minimizing uterine blood loss during the third stage of labor. Seventeen studies included 28170 subjects; of these, approximately one-half received misoprostol with the remainder receiving either a placebo or another uterotonic agent. An estimate of the odds ratio (OR) and risk difference for dichotomous outcomes was calculated using a random- and fixed-effects model. Continuous outcomes were pooled using a variance-weighted average of within-study difference in means.

RESULTS

In assessing studies comparing misoprostol with placebo, those who received oral misoprostol had a decreased risk of needing additional uterotonics (OR 0.64, 95% confidence interval 0.46, 0.90). Compared with placebo, use of misoprostol was associated with an increased risk for shivering and pyrexia. In contrast, in studies comparing misoprostol with oxytocin, oxytocin was associated with significantly lower rates of postpartum hemorrhage, maternal shivering and pyrexia. In studies comparing misoprostol with Syntometrine, misoprostol was associated with higher rates of the need for additional uterotonic agent as well as shivering.

CONCLUSIONS

Misoprostol was inferior to oxytocin and other uterotonics with regard to any of the third stage of labor outcomes assessed. However, when compared to placebo, misoprostol had a decreased risk of needing additional uterotonics. Thus, in less-developed countries where administration of parenteral uterotonic drugs may be problematic, misoprostol represents a reasonable agent for the management of the third stage of labor. Additional randomized clinical trials examining objective outcome measures (i.e. need for blood transfusion or 10% hemoglobin change) may further define benefits and risks of misoprostol use during the third stage of labor.

Oral misoprostol for the third stage of labor: a randomized controlled trial

OBJECTIVE

To compare oral misoprostol with conventional oxytocics in the management of the third stage of labor. In a controlled trial, 1574 women were randomized into four groups, as follows: Group 1 received intravenous infusion of oxytocin 10 IU plus oral misoprostol 400 micro g, followed by two doses of oral misoprostol 100 micro g 4 hours apart; group 2 received oral misoprostol 400 micro g, followed by two doses of oral misoprostol 100 micro g 4 hours apart; group 3 received intravenous infusion of oxytocin 10 IU; and group 4 received intravenous infusion of oxytocin 10 IU plus intramuscular administration of methylergonovine maleate (Methergine) 0.2 mg. The incidence of postpartum hemorrhage and decrease in hemoglobin concentration from before delivery to 24 hours postpartum were the main outcome measures.

RESULTS

The primary outcome measures were similar in groups 2 and 3. The incidence of postpartum hemorrhage was 9% in group 2, compared with 3.2% in group 1 and 3.5% in group 4 (P <.01, and P =.01, respectively). There were no significant differences among the four groups regarding hemoglobin concentrations. Significantly more women needed additional oxytocin in group 2, when compared with group 4 (5.9% versus 2.2%; P =.01). The proportion of women requiring additional methylergonovine maleate was 4.8% in group 2, compared with 0.7% in group 1 and 1% in group 4 (P <.01 and P =.01, respectively).

CONCLUSION

Oral misoprostol alone is as effective as oxytocin alone for the prevention of postpartum hemorrhage; it is less effective than oxytocin plus methylergonovine maleate and oral misoprostol plus oxytocin.

Management of obstetric hemorrhage

A reluctance to proceed with hysterectomy for obstetric hemorrhage may be a more likely cause of preventable death in obstetrics than a lack of surgical or medical skills. Every obstetric unit should have protocols available to deal with hemorrhage and, in addition, have specific guidelines for patients who object to blood transfusions for various reasons. Risk factors for hemorrhage should be identified antenatally, using all possible imaging modalities available, and utilizing multidisciplinary resources whenever possible. Novel strategies for prenatal diagnosis of abnormal placentation include advanced sonography and magnetic resonance imaging. Placement and utilization of arterial catheters for uterine artery embolization is becoming more widespread and new surgical technology such as the argon beam coagulator seems promising. When intra or postpartum hemorrhage is encountered, a familiar protocol for dealing with blood loss should be triggered. Timely hysterectomy should be performed for signs of refractory bleeding. Application of medical and surgical principles combined with recent technologic advances will help the obstetrician avoid disastrous outcomes for both mother and fetus.

The magnocellular oxytocin system, the fount of maternity: adaptations in pregnancy

Oxytocin secretion from the posterior pituitary gland is increased during parturition, stimulated by the uterine contractions that forcefully expel the fetuses. Since oxytocin stimulates further contractions of the uterus, which is exquisitely sensitive to oxytocin at the end of pregnancy, a positive feedback loop is activated. The neural pathway that drives oxytocin neurons via a brainstem relay has been partially characterised, and involves A2 noradrenergic cells in the brainstem. Until close to term the responsiveness of oxytocin neurons is restrained by neuroactive steroid metabolites of progesterone that potentiate GABA inhibitory mechanisms. As parturition approaches, and this inhibition fades as progesterone secretion collapses, a central opioid inhibitory mechanism is activated that restrains the excitation of oxytocin cells by brainstem inputs. This opioid restraint is the predominant damper of oxytocin cells before and during parturition, limiting stimulation by extraneous stimuli, and perhaps facilitating optimal spacing of births and economical use of the store of oxytocin accumulated during pregnancy. During parturition, oxytocin cells increase their basal activity, and hence oxytocin secretion increases. In addition, the oxytocin cells discharge a burst of action potentials as each fetus passes through the birth canal. Each burst causes the secretion of a pulse of oxytocin, which sharply increases uterine tone; these bursts depend upon auto-stimulation by oxytocin released from the dendrites of the magnocellular neurons in the supraoptic and paraventricular nuclei. With the exception of the opioid mechanism that emerges to restrain oxytocin cell responsiveness, the behavior of oxytocin cells and their inputs in pregnancy and parturition is explicable from the effects of hormones of pregnancy (relaxin, estrogen, progesterone) on pre-existing mechanisms, leading through relative quiescence at term inter alia to net increase in oxytocin storage, and reduced auto-inhibition by nitric oxide generation. Cyto-architectonic changes in parturition, involving evident retraction of glial processes between oxytocin cells so they get closer together, are probably a response to oxytocin neuron activation rather than being essential for their patterns of firing in parturition.

Acute uterine inversion: a review of 40 cases

OBJECTIVE

To determine the incidence, complications, and risk of recurrence of acute uterine inversion.

METHODS

A retrospective chart review was conducted of all cases of acute uterine inversion recorded at the Grace Maternity Hospital in Halifax, Nova Scotia, from 1977 to 2000.

RESULTS

During the 24-year period studied, 40 cases of acute uterine inversion occurred following 125,081 births. The incidence of acute uterine inversion following vaginal birth was 1 in 3737, and following Caesarean section, 1 in 1860. Post-partum hemorrhage complicated 65% of cases of acute uterine inversion, and 47.5% required blood transfusion. There was no recurrence in 26 subsequent deliveries. Following the institution of active management of the third stage of labour in 1988, the incidence of acute uterine inversion following vaginal delivery fell 4.4-fold.

CONCLUSION

Acute uterine inversion is rare but accompanied by high risk of postpartum hemorrhage and the need for blood transfusion. Active management of the third stage of labour may reduce the incidence of uterine inversion.

Preventing postpartum hemorrhage in low-resource settings

OBJECTIVES

To review the literature to determine the most effective methods for preventing postpartum hemorrhage (PPH), the single most important cause of maternal death worldwide.

METHODS

Systematic review of published randomized controlled trials and relevant reviews.

RESULTS

Review of the literature confirms that active management of the third stage of labor, especially the administration of uterotonic drugs, reduces the risk of PPH due to uterine atony without increasing the incidence of retained placenta or other serious complications. Oxytocin is the preferred uterotonic drug compared with syntometrine, but misoprostol also can be used to prevent hemorrhage in situations where parenteral medications are not available (e.g. at home births in developing countries).

CONCLUSIONS

The use of active management of the third stage of labor to prevent PPH due to uterine atony should be expanded, especially in developing country settings.