Pregnancy reference intervals and exertion and breathlessness ratings for the six minute walk test in healthy nulliparous people.

Background: The Six Minute Walk Test (6MWT) is a simple, non-invasive, well-validated test that assesses cardiorespiratory fitness however is rarely used in pregnant people. It may have clinical utilization to assess fitness, breathing and exertion in pregnancy however no reference intervals exist for people 14+0 to 35+6 weeks gestation. We determined the reference intervals for distance walked for the 6MWT, including exertional and breathlessness ratings for this group. Method: We conducted a prospective observational cohort study of 196 healthy nulliparous pregnant people in earlier pregnancy (EP) 14+0 to 23+6 weeks, and middle pregnancy (MP) 24+0 to 35+6 gestation, who performed a standardized 6MWT protocol including rating exertion and breathlessness (Rating Perceived Exertion (RPE) scale (1 none -15 maximal) and Modified Borg Dyspnea (MBD) scale (0 none - 10 maximal)). Results: The mean ± SD distance walked was 548 ± 80.9 (EP) versus 547 ± 87.3 (MP) meters (m) P = 0.928. 6MWT reference intervals for the distance walked for the 6MWT were 392-704 m (EP) and 376-718 m (MP). Median (IQR) exertion and breathlessness ratings with exercise for the EP and MP group were 6 (4,7) and 0.5 (0,1) and 6 (4,8) and 0.5 (0,1) respectively. There were no adverse events. Conclusion: The 6MWT is safe, feasible and acceptable in pregnant people. The reference intervals for the 6MWT are 392-704 m in people 14+0 to 23+6 weeks gestation and 376-718 m for people 24+0 to 35+6 weeks gestation. Exertion was light and breathlessness was just noticeable with the 6MWT.

Perioperative Exercise Testing in Pregnant and Non-Pregnant Women of Reproductive Age: A Systematic Review.

BACKGROUND: Women have classically been excluded from the development of normal data and reference ranges, with pregnant women experiencing further neglect. The incidence of Caesarean section in pregnant women, and of general operative management in young women (both pregnant and non-pregnant), necessitates the formal development of healthy baseline data in these cohorts to optimise their perioperative management. This systematic review assesses the representation of young women in existing reference ranges for several functional exercise tests in common use to facilitate functional assessment in this cohort. METHODS: Existing reference range data for the exercise tests the Six Minute Walk Test (6MWT), the Incremental Shuttle Walk Test (ISWT) and Cardiopulmonary Exercise Testing (CPET) in young women of reproductive age were assessed using the MEDLINE (Ovid) database, last searched December 2023. Results were comparatively tabulated but not statistically analysed given underlying variances in data. RESULTS: The role of exercise testing in the perioperative period as an assessment tool, as well as its safety during pregnancy, was evaluated using 65 studies which met inclusion criteria. CONCLUSION: There is a significant lack of baseline data regarding these tests in this population, especially amongst the pregnant cohort, which limits the application of exercise testing clinically.

Perioperative Complications in Patients with Preeclampsia Undergoing Caesarean Section Surgery.

Caesarean section has risks of bleeding, infection and thromboembolism, and neuroendocrine-metabolic, and inflammatory-immune responses that may worsen outcomes in patients with preeclampsia. There is little research examining perioperative, as opposed to peripartum, outcomes in patients with preeclampsia. We conducted a single-centrecentre retrospective cohort study of perioperative patients with preeclampsia over an eight-month period to determine the rate of perioperative complication. Seventy-two patients were included. The maternal complication rate was 59.7 per 100 operations (95% CI 48.2 to 70.3%). Severe complications included pulmonary oedema 2 (2.8%), haemorrhage > 1000 mL 5 (6.9%), and blood transfusion 2 (2.8%). Twenty (27.8%) patients had a hospital length of stay ≥7 days. The rate of anaemia (haemoglobin < 110 g/L) on hospital discharge was 42 per 100 operations (95% CI 31.0 to 53.2%). Patient representation rate to hospital after discharge was 23.6% per 100 operations (95% CI 15.3 to 34.6%). There were no maternal deaths. The neonatal complication rate was 38.9 per 100 operations (95% CI 28.9 to 51.1%) with one foetal death. Patients with preeclampsia undergoing caesarean section are a very high-risk surgical group who experience significant perioperative complications. Urgent action is needed to confirm these findings and improve outcomes in these patients.

Analysis of anaesthesia incidents during caesarean section reported to webAIRS between 2009 and 2022.

Anaesthesia for caesarean section occurs commonly and places specific demands on anaesthetists. We analysed 469 narratives concerning anaesthesia for caesarean section, entered by Australian and New Zealand anaesthetists into the webAIRS incident reporting system between 2009 and 2022. As expected, compared with the remaining 8978 database entries, the 469 incidents were more likely to be emergency cases (relative risk (RR) 1.95), more likely to occur between 18:00 and 22:00 hours (RR 1.81) and between 22:00 and 07:59 hours (RR 4.40) and more likely to be undertaken using neuraxial anaesthesia (RR 9.18). Most incidents involved more than one event. The most commonly reported incidents included intraoperative neuraxial anaesthesia complications (180, 38%), medication errors or issues (136, 29%), equipment issues (49, 10%), obstetric haemorrhage (38, 8%), maternal cardiac arrests (28, 6%), endotracheal tube issues (28, 6%) and neonatal resuscitation (24, 5%). Inadequate neuraxial block, reported in 95 incidents, was the most common intraoperative neuraxial complication. Allergic reactions, reported in 30 incidents, were the most common medication issue, followed by 17 associated with oxytocin and 16 syringe swaps. Thirty-eight reports included significant maternal haemorrhage, with eight of those incidents including maternal cardiac arrest. There was one maternal death and eight incidents with neonatal deaths reported, affecting nine neonates. Problems with intraoperative neuraxial anaesthesia were the most commonly reported events. Implementation of specific strategies are encouraged to enhance preparation for conversion to general anaesthesia and to mitigate medication errors, particularly those relating to oxytocic use and neuraxial anaesthesia medications.

The prevalence of perioperative iron deficiency anaemia in women undergoing caesarean section-a retrospective cohort study.

BACKGROUND: Caesarean section is a common surgery, with almost 23 million procedures performed globally each year. Postpartum haemorrhage, in association with caesarean section surgery, is a leading global cause of maternal morbidity and mortality. Perioperative iron deficiency anaemia is a risk factor for intraoperative bleeding. Therefore, anaemia is an important and modifiable risk factor for bleeding during caesarean section surgery. Recent recommendations advise that all preoperative patients with anaemia (defined as haemoglobin concentration (Hb) < 130 g/L), regardless of sex, be assessed and treated to normalise haemoglobin levels. It is unclear how this recommendation translates to pregnant women where the World Health Organization (WHO) defines anaemia at a much lower threshold (Hb < 110 g/L). We aimed to determine the prevalence, and characterization, of Hb levels < 130 g/L perioperatively in women undergoing caesarean section. METHOD: We conducted a retrospective cohort study of 489 consecutive women who underwent caesarean section over a 12-week period, in a single-centre tertiary referral maternity unit in Australia. We calculated the proportion of women who were anaemic (Hb < 130 g/L) at four time points-first hospital appointment, third trimester, preoperatively and on discharge from hospital. The proportion of women who were iron deficient (ferritin level < 30 µg/L) at their first hospital appointment was determined. RESULTS: Haemoglobin was measured in 479 women. Ferritin was measured in 437 of these women. The mean (SD) Hb at the first hospital appointment, third trimester, preoperatively, and postoperatively on discharge was 126.7 (11.4) g/L, 114.6 (10.6) g/L, 124.1 (12.4) g/L, and 108.0 (13.6) g/L respectively. Iron deficiency was present in 148 (33.9%) women at their first hospital appointment; 107 of 248 (43.1%) women with anaemia and 41 of 189 (21.7%) with no anaemia. 29 women were found to have moderate anaemia (Hb 80-109 g/L) with 18 of these 29 (62.1%) women having iron deficiency. Only 68 (45.9%) women with iron deficiency at their first hospital appointment received treatment. The prevalence of anaemia classified as Hb < 130 g/L versus the WHO classification of Hb < 110 g/L from all causes was 57.4% versus 6.1% at first hospital appointment, 94% versus 26.1% in third trimester, and 66.0% versus 12.2% preoperatively. Postoperatively at least 40% of women had Hb < 130 g/L on hospital discharge versus at least 23% of women using WHO definition of Hb < 110 g/L. Of the 112 women with hospital discharge Hb < 110 g/L, 35 (31.3%) women were iron deficient at their first hospital appointment. CONCLUSION: Over one in three women were iron deficient at their first hospital appointment. 62% of women with moderate anaemia (Hb 80-109 g/L) also had iron deficiency. At least four in 10 women were anaemic (Hb < 130 g/L) on hospital discharge. Less than half of the women with anaemia were treated. Our data suggests that 30% of postoperative anaemia may be prevented with intensive treatment of iron deficiency in early pregnancy. Large prospective studies, are needed to determine outcomes after caesarean section in women, stratified by preoperative Hb and ferritin levels. The prevalence of anaemia in our data suggests it is a moderate public health problem.

Combined spinal-epidural versus spinal anaesthesia for caesarean section.

BACKGROUND: Single-shot spinal anaesthesia (SSS) and combined spinal-epidural (CSE) anaesthesia are both commonly used for caesarean section anaesthesia. Spinals offer technical simplicity and rapid onset of nerve blockade which can be associated with hypotension. CSE anaesthesia allows for more gradual onset and also prolongation of the anaesthesia through use of a catheter. OBJECTIVES: To compare the effectiveness and adverse effects of CSE anaesthesia to single-shot spinal anaesthesia for caesarean section. SEARCH METHODS: We searched the Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP), and reference lists of retrieved studies (search date: 8 August 2019). SELECTION CRITERIA: We considered all published randomised controlled trials (RCTs) involving a comparison of CSE anaesthesia with single-shot spinal anaesthesia for caesarean section. We further subgrouped spinal anaesthesia as either high-dose (10 or more mg bupivacaine), or low-dose (less than 10 mg bupivacaine). DATA COLLECTION AND ANALYSIS: Two review authors independently assessed trials for inclusion and risks of bias, extracted data and checked them for accuracy. We used standard methodological procedures expected by Cochrane. MAIN RESULTS: We identified 18 trials including 1272 women, but almost all comparisons for individual outcomes involved relatively small numbers of women. Two trials did not report on this review's outcomes and therefore contribute no data towards this review. Trials were conducted in national or university hospitals in Australia (1), Croatia (1), India (1), Italy (1), Singapore (3), South Korea (4), Spain (1), Sweden (1), Turkey (2), UK (1), USA (2). The trials were at a moderate risk of bias overall.CSE versus high-dose spinal anaesthesiaThere may be little or no difference between the CSE and high-dose spinal groups for the number of women requiring a repeat regional block or general anaesthetic as a result of failure to establish adequate initial blockade (risk ratio (RR) 0.32, 95% confidence interval (CI) 0.05 to 1.97; 7 studies, 341 women; low-quality evidence). We are uncertain whether having CSE or spinal makes any difference in the number of women requiring supplemental intra-operative analgesia at any time after CSE or spinal anaesthetic insertion (average RR 1.25, 95% CI 0.19 to 8.43; 7 studies, 390 women; very low-quality evidence), or the number of women requiring intra-operative conversion to general anaesthesia (RR 1.00, 95% CI 0.07 to 14.95; 7 studies, 388 women; very low-quality evidence). We are also uncertain about the results for the number of women who were satisfied with anaesthesia, regardless of whether they received CSE or high-dose spinal (RR 0.93 95% CI 0.73 to 1.19; 2 studies, 72 women; very low-quality evidence). More women in the CSE group (13/21) experienced intra-operative nausea or vomiting requiring treatment than in the high-dose spinal group (6/21). There were 11 cases of post-dural puncture headache (5/56 with CSE versus 6/57 with SSS; 3 trials, 113 women) with no clear difference between groups. There was also no clear difference in intra-operative hypotension requiring treatment (46/86 with CSE versus 41/76 with SSS; 4 trials, 162 women). There were no babies with Apgar score less than seven at five minutes (4 trials, 182 babies).CSE versus low-dose spinal anaesthesiaThere may be little or no difference between the CSE and low-dose spinal groups for the number of women requiring a repeat regional block or general anaesthetic as a result of failure to establish adequate initial blockade (RR 4.81, 95% CI 0.24 to 97.90; 3 studies, 224 women; low-quality evidence). Similarly, there is probably little difference in the number of women requiring supplemental intra-operative analgesia at any time after CSE or low-dose spinal anaesthetic insertion (RR 1.75, 95% CI 0.78 to 3.92; 4 studies, 298 women; moderate-quality evidence). We are uncertain about the effect of CSE or low-dose spinal on the need for intra-operative conversion to general anaesthesia, because this was not required by any of the 222 women in the three trials (low-quality evidence). None of the studies examined whether women were satisfied with their anaesthesia.The mean time to effective anaesthesia was faster in women who received low-dose spinal compared to CSE, although it is unlikely that the magnitude of this difference is clinically meaningful (standardised mean difference (SMD) 0.85 minutes, 95% CI 0.52 to 1.18 minutes; 2 studies, 160 women).CSE appeared to reduce the incidence of intra-operative hypotension requiring treatment compared with low-dose spinal (average RR 0.59, 95% CI 0.38 to 0.93; 4 studies, 336 women). Similar numbers of women between the CSE and low-dose spinal groups experienced intra-operative nausea or vomiting requiring treatment (3/50 with CSE versus 6/50 with SSS; 1 study, 100 women), and there were no cases of post-dural puncture headache (1 study, 138 women). No infants in either group had an Apgar score of less than seven at five minutes (1 study; 60 babies). AUTHORS' CONCLUSIONS: In this review, the number of studies and participants for most of our analyses were small and some of the included trials had design limitations. There was some suggestion that, compared to spinal anaesthesia, CSE could be associated with a reduction in the number of women with intra-operative hypotension, but an increase in intra-operative nausea and vomiting requiring treatment. One small study found that low-dose spinal resulted in a faster time to effective anaesthesia compared to CSE. However, these results are based on limited data and the difference is unlikely to be clinically meaningful. Consequently, there is currently insufficient evidence in support of one technique over the other and more evidence is needed in order to further evaluate the relative effectiveness and safety of CSE and spinal anaesthesia for caesarean section.More high-quality, sufficiently-powered studies in this area are needed. Such studies could consider using the outcomes listed in this review and should also consider reporting economic aspects of the different methods under investigation.

Optic nerve sonography and ophthalmic artery Doppler velocimetry in healthy pregnant women: an Australian cohort study.

PURPOSE: Maternal ocular sonography offers a window into cerebrovascular and intracranial pressure changes in pregnancy. This study aimed to determine the Doppler velocimetric variables of the ophthalmic artery, and the mean diameter of the optic nerve sheath (ONSD), in an Australian cohort of healthy pregnant women. METHODS: A prospective observational cohort study of healthy women with uncomplicated singleton pregnancies in the third trimester was undertaken in a tertiary maternity service. A single prenatal ultrasonographic examination was performed on all participants, with a postnatal examination performed on a subgroup with uncomplicated deliveries. RESULTS: Fifty women were examined at a mean gestation of 35 weeks. The mean ± SD Doppler variables in the ophthalmic artery were peak systolic velocity (PSV) 41.89 ± 13.13 cm/s, second peak velocity 20.63 ± 8.97 cm/s, end diastolic velocity 9.29 ± 5.13 cm/s, pulsatility index 1.97 ± 0.53, resistive index 0.78 ± 0.07, peak ratio (second peak velocity/PSV) 0.49 ± 0.12, while the mean ONSD was 4.34 ± 0.4 mm. None of these variables had a demonstrable relationship with gestation or mean arterial pressure (MAP), nor did the sheath diameter have a relationship with any of the Doppler variables. CONCLUSIONS: The ocular sonographic variables observed in this population are similar to those reported in other cohorts. No clear relationship could be identified in this cohort between ophthalmic artery Doppler variables and the ONSD, and between each of these variables and gestation or MAP.

The prone position in healthy pregnant women and in women with preeclampsia - a pilot study.

BACKGROUND: The prone position is rarely used in medical settings in pregnancy. There is no published information about the prone position in women with preeclampsia. This study examined the feasibility and acceptability of the prone position in pregnant women, and the short-term effect of the prone position on blood pressure (BP) in term healthy pregnant women and in women with preeclampsia. METHODS: After ethics approval, written consent and trial registration (ACTRN:12615000160538 registered 18/02/2015, date of first participant enrolled 03/03/2015), 50 healthy term pregnant women and 15 women with preeclampsia had BP, heart rate (HR), oxygen saturation (SpO2), respiratory rate (RR), fetal heart rate (FHR) and comfort levels measured in two positions: left lateral, and prone. Measurements were after five minutes rest in each position. RESULTS: Mean ± SD age, gestation and body mass index for healthy pregnant women was 33 ± 4.1 years, 38 ± 1.0 weeks and 27 ± 3.2 kg.m- 2 and for women with preeclampsia was 32 ± 4.7 years, 36 ± 3.4 weeks, 31 ± 5.6 kg.m- 2 respectively. No clinically significant changes occurred in healthy pregnant women in the prone position. Systolic BP was reduced in the prone position in women with preeclampsia (P = 0.019, mean difference - 6.6 mmHg, 95% confidence interval - 11.9 to - 1.3 mmHg). 33% of women with preeclampsia experienced a 10 mmHg or greater reduction in systolic BP in the prone position. 42% of healthy pregnant women and 47% of women with preeclampsia preferred the prone position to lateral. CONCLUSIONS: This is the first study to examine the prone position in women with preeclampsia. For short periods of time the prone position is feasible and comfortable in pregnant women including those at term. The prone position may reduce systolic BP in women with preeclampsia without obvious adverse effects. Larger studies with women lying for longer periods in the prone position are required. Pregnancy should not be a contraindication to the prone position for short periods of time. TRIAL REGISTRATION: ACTRN:12615000160538.

Baby-directed umbilical cord clamping: A feasibility study.

INTRODUCTION: Over five percent of infants born worldwide will need help breathing after birth. Delayed cord clamping (DCC) has become the standard of care for vigorous infants. DCC in non-vigorous infants is uncommon because of logistical difficulties in providing effective resuscitation during DCC. In Baby-Directed Umbilical Cord Clamping (Baby-DUCC), the umbilical cord remains patent until the infant's lungs are exchanging gases. We conducted a feasibility study of the Baby-DUCC technique. METHODS: We obtained antenatal consent from pregnant women to enroll infants born at ≥32 weeks. Vigorous infants received ≥2 min of DCC. If the infant received respiratory support, the umbilical cord was clamped ≥60 s after the colorimetric carbon dioxide detector turned yellow. Maternal uterotonic medication was administered after umbilical cord clamping. A paediatrician and researcher entered the sterile field to provide respiratory support during a cesarean birth. Maternal and infant outcomes in the delivery room and prior to hospital discharge were analysed. RESULTS: Forty-four infants were enrolled, 23 delivered via cesarean section (8 unplanned) and 15 delivered vaginally (6 via instrumentation). Twelve infants were non-vigorous. ECG was the preferred method for recording HR. Two infants had a HR < 100 BPM. All HR values were >100 BPM by 80 s after birth. Median time to umbilical cord clamping was 150 and 138 s in vigorous and non-vigorous infants, respectively. Median maternal blood loss was 300 ml. CONCLUSIONS: It is feasible to provide resuscitation to term and near-term infants during DCC, after both vaginal and cesarean births, clamping the umbilical cord only when the infant is physiologically ready.

Reducing Maternal Mortality in Papua New Guinea: Contextualizing Access to Safe Surgery and Anesthesia.

Papua New Guinea has one of the world's highest maternal mortality rates with approximately 215 women dying per 100,000 live births. The sustainable development goals outline key priority areas for achieving a reduction in maternal mortality including a focus on universal health coverage with safe surgery and anesthesia for all pregnant women. This narrative review addresses the issue of reducing maternal mortality in Papua New Guinea by contextualizing the need for safe obstetric surgery and anesthesia within a structure of enabling environments at key times in a woman's life. The 3 pillars of enabling environments are as follows: a stable humanitarian government; a safe, secure, and clean environment; and a strong health system. Key times, and their associated specific issues, in a woman's life include prepregnancy, antenatal, birth and the postpartum period, childhood, adolescence and young womanhood, and the postchildbearing years.

Doppler Assessment of Uterine Blood Flow in Pre-eclampsia: A Review.

Doppler ultrasonography plays an ever-increasing role in obstetric imaging. Although commonly purported to assess blood flow, most studies in this area report purely on velocimetric parameters, rather than true volumetric flow. This review article highlights the physiological importance of this distinction, and reports on a literature review of uterine artery Doppler interrogation in the context of pre-eclampsia, which identified only four original research papers that attempted to assess blood flow. Attention is needed for true volumetric flow assessment in pre-eclampsia research, which may permit a more complete conceptualisation of the pathogenesis and haemodynamic consequences of this condition.

Transthoracic echocardiography in women with preeclampsia.

PURPOSE OF REVIEW: Recent literature on the role of transthoracic echocardiography in the management of women with preeclampsia is reviewed with emphasis on recommendations for its use in the life-threatening complications of acute pulmonary edema, chest pain, and hemorrhage. RECENT FINDINGS: The diagnostic criteria for preeclampsia are closer to reaching international consensus with most guidelines now removing the mandatory requirement for proteinuria. Hemodynamic findings using transthoracic echocardiography in women with untreated preeclampsia include normal or increased cardiac output, normal or increased contractility, a nondilated left ventricle, diastolic dysfunction, increased pericardial effusions, and increased left ventricular mass. Echocardiography is recommended as a diagnostic and monitoring tool for acute hemodynamic complications of preeclampsia, such as acute pulmonary edema, significant arterial hypertension, and chest pain. Despite this there has been limited uptake of transthoracic electrocardiography into routine clinical practice in women with preeclampsia. SUMMARY: The role of transthoracic echocardiography in the management of women with preeclampsia is emphasized by international groups. Research into the hemodynamics in preeclampsia, which demonstrates preserved ejection fraction, and diastolic dysfunction highlights its utility and acceptability by pregnant women with preeclampsia. Training of obstetric anesthesiologists in echocardiography is necessary to enable more widespread implementation of this important technology.

New diagnosis myasthenia gravis and preeclampsia in late pregnancy.

Myasthenia gravis is a chronic autoimmune disease of neuromuscular transmission resulting in fatigable skeletal muscle weakness. Preeclampsia is a multisystem disease of pregnancy which is characterised by hypertension and involvement of one or more organ systems. Both diseases are responsible for considerable morbidity and mortality for mother and fetus. The occurrence of both preeclampsia and myasthenia gravis in pregnancy is very rare, and conflicts arise when considering the optimal management of each disease.We present a case of a parturient who was newly diagnosed with both myasthenia gravis and preeclampsia in late pregnancy. Myasthenia treatment was started with prednisolone and pyridostigmine, and delivery was by caesarean section at 37 weeks gestation under spinal anaesthesia. Postnatally, the patient developed worsening of myasthenia and preeclampsia symptoms. We consider the anaesthetic implications for both diseases and describe our approach for the management of this case.

Combined spinal-epidural versus epidural analgesia in labour.

BACKGROUND: Traditional epidural techniques have been associated with prolonged labour, use of oxytocin augmentation and increased incidence of instrumental vaginal delivery. The combined spinal-epidural (CSE) technique has been introduced in an attempt to reduce these adverse effects. CSE is believed to improve maternal mobility during labour and provide more rapid onset of analgesia than epidural analgesia, which could contribute to increased maternal satisfaction. OBJECTIVES: To assess the relative effects of CSE versus epidural analgesia during labour. SEARCH METHODS: We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (28 September 2011) and reference lists of retrieved studies. We updated the search on 30 June 2012 and added the results to the awaiting classification section. SELECTION CRITERIA: All published randomised controlled trials (RCTs) involving a comparison of CSE with epidural analgesia initiated for women in the first stage of labour. Cluster-randomised trials were considered for inclusion. Quasi RCTs and cross-over trials were not considered for inclusion in this review. DATA COLLECTION AND ANALYSIS: Three review authors independently assessed the trials identified from the searches for inclusion, assessed trial quality and extracted the data. Data were checked for accuracy. MAIN RESULTS: Twenty-seven trials involving 3274 women met our inclusion criteria. Twenty-six outcomes in two sets of comparisons involving CSE versus traditional epidurals and CSE versus low-dose epidural techniques were analysed.Of the CSE versus traditional epidural analyses five outcomes showed a significant difference. CSE was more favourable in relation to speed of onset of analgesia from time of injection (mean difference (MD) -2.87 minutes; 95% confidence interval (CI) -5.07 to -0.67; two trials, 129 women); the need for rescue analgesia (risk ratio (RR) 0.31; 95% CI 0.14 to 0.70; one trial, 42 women); urinary retention (RR 0.86; 95% CI 0.79 to 0.95; one trial, 704 women); and rate of instrumental delivery (RR 0.81; 95% CI 0.67 to 0.97; six trials, 1015 women). Traditional epidural was more favourable in relation to umbilical venous pH (MD -0.03; 95% CI -0.06 to -0.00; one trial, 55 women). There were no data on maternal satisfaction, blood patch for post dural puncture headache, respiratory depression, umbilical cord pH, rare neurological complications, analgesia for caesarean section after analgesic intervention or any economic/use of resources outcomes for this comparison. No differences between CSE and traditional epidural were identified for mobilisation in labour, the need for labour augmentation, the rate of caesarean birth, incidence of post dural puncture headache, maternal hypotension, neonatal Apgar scores or umbilical arterial pH.For CSE versus low-dose epidurals, three outcomes were statistically significant. Two of these reflected a faster onset of effective analgesia from time of injection with CSE and the third was of more pruritus with CSE compared to low-dose epidural (average RR 1.80; 95% CI 1.22 to 2.65; 11 trials, 959 women; random-effects, T² = 0.26, I² = 84%). There was no significant difference in maternal satisfaction (average RR 1.01; 95% CI 0.98 to 1.05; seven trials, 520 women; random-effects, T² = 0.00, I² = 45%). There were no data on respiratory depression, maternal sedation or the need for labour augmentation. No differences between CSE and low-dose epidural were identified for need for rescue analgesia, mobilisation in labour, incidence of post dural puncture headache, known dural tap, blood patch for post dural headache, urinary retention, nausea/vomiting, hypotension, headache, the need for labour augmentation, mode of delivery, umbilical pH, Apgar score or admissions to the neonatal unit. AUTHORS' CONCLUSIONS: There appears to be little basis for offering CSE over epidurals in labour, with no difference in overall maternal satisfaction despite a slightly faster onset with CSE and conversely less pruritus with low-dose epidurals. There was no difference in ability to mobilise, maternal hypotension, rate of caesarean birth or neonatal outcome. However, the significantly higher incidence of urinary retention, rescue interventions and instrumental deliveries with traditional techniques would favour the use of low-dose epidurals. It is not possible to draw any meaningful conclusions regarding rare complications such as nerve injury and meningitis.

Haemodynamics using transthoracic echocardiography in healthy pregnant and non-pregnant baboons (Papio hamadryas).

BACKGROUND: To determine systolic and diastolic function using transthoracic echocardiography in the baboon (Papio hamadryas). METHODS: Transthoracic echocardiography was performed in eight non-pregnant female and six pregnant baboons according to American Society of Echocardiography recommendations. RESULTS: Haemodynamic measurements were obtained from fourteen baboons. Compared to non-pregnant baboons, pregnant baboons demonstrated: (mean ± SD, pregnant vs. healthy) increased cardiac output (1615 ± 121 ml/minutes vs. 1317 ± 134 ml/minutes P = 0.001) due to an increased heart rate [120 ± 11 beats per minute (BPM) vs. 105 ± 6 BPM P = 0.018]. The inter-observer and intra-observer variability (mean difference ± SD) for the left ventricular outflow tract diameter was 0.05 ± 0.07 cm and 0.01 ± 0.03 cm respectively. There was minimal impact to the animal's daily activities. CONCLUSIONS: Transthoracic echocardiography was applicable and reproducible for the assessment of haemodynamics in baboons thus enabling translation of animal results to human studies.