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Hypothermia during obstetric spinal anaesthesia is a common and important problem, yet temperature monitoring is often not performed due to the lack of a suitable, cost-effective monitor. This study aimed to compare a noninvasive core temperature monitor with two readily available peripheral temperature monitors during obstetric spinal anaesthesia. We undertook a prospective observational study including elective and emergency caesarean deliveries, to determine the agreement between affordable reusable surface temperature monitors (Welch Allyn SureTemp® Plus oral thermometer and the Braun 3-in-1 No Touch infrared thermometer) and the Dräger T-core© (using dual-sensor heat flux technology), in detecting thermoregulatory changes during obstetric spinal anaesthesia. Predetermined clinically relevant limits of agreement (LOA) were set at ± 0.5 °C. We included 166 patients in our analysis. Hypothermia (heat flux temperature < 36 °C) occurred in 67% (95% CI 49 to 78%). There was poor agreement between devices. In the Bland-Altman analysis, LOA for the heat flux monitor vs. oral thermometer were 1.8 °C (CI 1.7 to 2.0 °C; bias 0.5 °C), for heat flux monitor vs. infrared thermometer LOA were 2.3 °C (CI 2.1 to 2.4 °C; bias 0.4 °C) and for infrared vs. oral thermometer, LOA were 2.0 °C (CI 1.9 to 2.2 °C; bias 0.1 °C). Error grid analysis highlighted a large amount of clinical disagreement between methods. While monitoring of core temperature during obstetric spinal anaesthesia is clinically important, agreement between monitors was below clinically acceptable limits. Future research with gold-standard temperature monitors and exploration of causes of sensor divergence is needed., (© 2024. The Author(s).)

Background: Postoperative nausea and vomiting is one of the most common anaesthetic complications of caesarean section. This study examined the association between hyperemesis gravidarum during pregnancy and nausea and vomiting after caesarean section., Methods: A single-centre, retrospective cohort study, using electronic databases of patients with and without hyperemesis gravidarum, undergoing caesarean section from 2015 to 2019. The incidence and severity of postoperative nausea and vomiting were established by a review of the documentation of administration of postoperative anti-emetics within the 24-h period after surgery, and examined using univariable, multivariable binary and ordered logistic regression models., Results: Data were compared for 76 patients with hyperemesis gravidarum and 315 patients without the condition. The incidence of postoperative nausea and vomiting in the hyperemesis group versus the non-hyperemesis group was 43.4% vs 29.6%, respectively. The odds of experiencing postoperative nausea and vomiting was 1.95 times higher in women with hyperemesis gravidarum than in those without (aOR 1.95, 95% CI 1.13 to 3.36, P=0.016). The odds of having more severe postoperative nausea and vomiting were greater in the hyperemesis gravidarum group (aOR 1.91, 95% CI 1.14 to 3.20, P=0.014)., Conclusion: Patients with hyperemesis gravidarum are more likely to develop nausea and vomiting after caesarean section, and this is likely to be of greater severity than in those without the condition. This finding should assist the effective provision of intra-operative and postoperative anti-emetics for patients with hyperemesis gravidarum undergoing caesarean section., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Spinal hypotension is a common and clinically important problem during caesarean section. Current consensus recommendations for resource-rich settings suggest the use of a titrated phenylephrine infusion, in combination with fluid coloading, for prevention of maternal hypotension. In resource-limited settings, where syringe drivers are unavailable, these recommendations advise the addition of 500 μg phenylephrine to the first 1 l of intravenous fluid given after initiation of spinal anaesthesia, with additional vasopressor boluses as required. This prospective, alternating intervention study compared the use of a conventional phenylephrine rescue bolus strategy for prevention of hypotension, defined as systolic arterial pressure < 90 mmHg, with a phenylephrine infusion given according to the consensus recommendation. We studied 300 women having elective caesarean section. There were 77 (51%) women who developed hypotension in the bolus group vs. 55 (37%) in the phenylephrine infusion group (p = 0.011). This represented a 29% reduction in hypotension, with a number needed to treat of 6.8. The six highest systolic arterial pressure readings occurred in the phenylephrine infusion group (range 166-188 mmHg), and there were four instances of bradycardia (heart rate < 50 beats.min -1 ) with preserved systolic arterial pressure in each group. There were no adverse clinical sequelae, and no differences in neonatal Apgar scores in either group. The consensus recommendation for phenylephrine and fluid co-administration in resource-limited settings appears effective in preventing maternal hypotension, but at the cost of sporadic systolic hypertension., (© 2019 Association of Anaesthetists.)

Post-caesarean pain is an important and often neglected outcome. It causes suffering, affects breastfeeding and is associated with postpartum depression and the development of chronic pain syndromes. Pain control is often difficult even in resource-rich environments; it is likely far worse in resource-limited settings, where emphasis is on reducing the high maternal mortality rate. Lack of adequate staffing, education, and postoperative monitoring severely limit the options in resource-limited settings. Resource-limited settings are further compromised by limited access to essential analgesic drugs and equipment for their administration. Solutions using affordable and accessible medications as part of a multimodal analgesic strategy are possible, supplemented by education and training programmes. More research is required, both to establish current practice and to test methods for improving maternal pain control. While government involvement is necessary to improve infrastructure and resources in individual countries, other solutions should also be sought, empowering local institutions and harnessing individual cultural characteristics., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

It is routine to give a uterotonic drug following delivery of the neonate during caesarean section. However, there is much heterogeneity in the relevant research, which has largely been performed in low-risk elective cases or women with uncomplicated labour. This is reflected in considerable variation in clinical practice. There are significant differences between dose requirements during elective and intrapartum caesarean section. Standard recommended doses are higher than required, with the potential for acute cardiovascular adverse effects. We recommend a small initial bolus dose of oxytocin, followed by a titrated infusion. The recommended doses of oxytocin may have to be increased in women with risk factors for uterine atony. Carbetocin at equipotent doses to oxytocin has similar actions, while avoiding the requirement for a continuous infusion after the initial dose and reducing the need for additional uterotonics. As with oxytocin, carbetocin dose requirements are higher for intrapartum caesarean sections. A second-line agent should be considered early if oxytocin/carbetocin fails to produce good uterine tone. Women with cardiac disease may be very sensitive to the adverse effects of oxytocin and other uterotonics, and their management needs to be individualised., (© 2019 Association of Anaesthetists.)

We examined the haemodynamic effects of colloid preload, and phenylephrine and ephedrine administered for spinal hypotension, during caesarean section in 42 women with severe early onset pre-eclampsia. Twenty patients with pre-delivery spinal hypotension were randomly allocated to receive an initial dose of either 50 μg phenylephrine or 7.5 mg ephedrine; the primary outcome was percentage change in cardiac index. After a 300-ml colloid preload, mean (SD) cardiac index increased from 4.9 (1.1) to 5.6 (1.2) l.min -1 .m -2 (p < 0.01), resulting from an increase in both heart rate, from 81.3 (17.2) to 86.3 (16.5) beats.min -1 (p = 0.2), and stroke volume, from 111.8 (19.0) to 119.8 (17.9) ml (p = 0.049). Fourteen (33%) and 23 (54.8%) patients exhibited a stroke volume response > 10% and > 5%, respectively; a significant negative correlation was found between heart rate and stroke volume changes. Spinal hypotension in 20 patients was associated with an increase from baseline in cardiac index of 0.6 l.min -1 .m -2 (mean difference 11.5%; p < 0.0001). After a median [range] dose of 50 [50-150] μg phenylephrine or 15 [7.5-37.5] mg ephedrine, the percentage change in cardiac index during the measurement period of 150 s was greater, and negative, in patients receiving phenylephrine vs. ephedrine, at -12.0 (7.3)% vs. 2.6 (6.0)%, respectively (p = 0.0001). The percentage change in heart rate after vasopressor was higher in patients receiving phenylephrine, at -9.1 (3.4)% vs. 5.3 (12.6)% (p = 0.0027), as was the change in systemic vascular resistance, at 22.3 (7.5) vs. -1.9 (10.5)% (p < 0.0001). Phenylephrine effectively reverses spinal anaesthesia-induced haemodynamic changes in severe pre-eclampsia, if left ventricular systolic function is preserved., (© 2017 The Association of Anaesthetists of Great Britain and Ireland.)

Background: It has been suggested that the dose requirement for spinal anesthesia (SA) is lower in obese patients for cesarean delivery (CD). In this prospective, observational, noninferiority study, we tested the hypothesis that obesity would not have a clinically important effect on vasopressor requirements or block height., Methods: Two groups of 25 parturients, group O (body mass index [BMI] >40 kg/m) and group N (BMI <32 kg/m) requiring elective CD were recruited. All patients received 10 mg intrathecal hyperbaric bupivacaine coadministered with 10 μg fentanyl. Dermatomal levels were assessed at 5 and 25 minutes after SA, and at completion of surgery, using light touch and cold sensation in response to ethyl chloride. The primary outcomes were phenylephrine requirement in the first 30 minutes after SA, and maximum block height, measured by the sensation of touch and cold. Secondary outcomes were total phenylephrine dose required, changes in hand grip strength, and peak flow rate., Results: There were no significant between-group differences in median block height as assessed by touch at 5 or 25 minutes or by temperature at 5 minutes. At 25 minutes, there was a 2-dermatome difference in median block height for loss of temperature sensation between group O and group N (T2 vs T4, 95% confidence interval [CI] of the difference in medians 0-2 dermatomes). No blocks extended to cervical dermatomes. The median (range) phenylephrine dose for the first 30 minutes was 150 µg (0-900 µg), and 100 µg (0-1250 µg) in group N and group O, respectively. The 95% CI for the difference between the 2 median doses was -150 µg to 100 µg. There were no differences in median percentage reductions in peak flow rate or median hand grip strength after SA. Mean surgical time was longer in group O than in group N (49.1 vs 39.4 min, 95% CI difference 1.7-17.7 min). The mean time for recovery of touch sensation to T10 was longer in group O (152 vs 132 min, 95% CI difference 3.8-36.2 min). No analgesic supplementation was required., Conclusion: Only a minor increase in block height as assessed by temperature occurred in group O at 25 minutes. Vasopressor requirements during the first 30 minutes of SA were equivalent. Time for regression of SA block level was longer in the group O, which may be beneficial considering the longer surgical time. A dose of spinal bupivacaine 10 mg for single-shot SA should not be reduced in morbidly obese parturients.

Background: Oxytocin causes clinically significant hypotension and tachycardia. This study examined whether prior administration of phenylephrine obtunds these unwanted haemodynamic effects., Methods: Forty pregnant women undergoing elective caesarean section under spinal anaesthesia were randomised to receive either an intravenous 50 μg bolus of phenylephrine (Group P) or saline (Group S) immediately before oxytocin (3U over 15s). Systolic blood pressure, diastolic blood pressure, mean arterial pressure and heart rate were recorded using a continuous non-invasive arterial pressure device. Baseline values were averaged for 20s post-delivery. Between-group comparisons were made of the mean peak changes in blood pressure and heart rate, and the mean percentage changes from baseline, during the 150s after oxytocin administration., Results: The mean ± SD peak percentage change in systolic blood pressure was -16.9 ± 2% in Group P, and -19.0 ± 1.9% in Group S and the estimated mean difference was 2.1% (95% CI -3.5% to 7.8%; P=0.44); corresponding changes in heart rate were 13.5 ± 2.3% and 14.0±1.5% and the mean estimated difference was 0.5% (95% CI -6.0% to 5%; P=0.87). The mean percentage change from the baseline measurements during the 150s period of measurement was greater for Group S than Group P: systolic blood pressure -5.9% vs -3.4% (P=0.149); diastolic blood pressure -7.2% vs -1.5% (P=0.014); mean arterial pressure -6.8% vs -1.5% (P=0.007); heart rate 2.1% vs -2.4% (P=0.033)., Conclusion: Intravenous phenylephrine 50 μg immediately before 3U oxytocin during elective caesarean section does not prevent maternal hypotension and tachycardia., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The administration of oxytocic drugs during caesarean section is an important intervention to prevent uterine atony or treat established postpartum haemorrhage. Considerable past and current research has shown that these agents have a narrow therapeutic range. A detailed knowledge by anaesthetists of optimal doses and side effects is therefore required. Oxytocin remains the first line agent. In view of receptor desensitisation, second line agents may be required, namely ergot alkaloids and prostaglandins. This review examines the adverse haemodynamic and side effects, and methods for their limitation. An approach to dosing and choices of agent for the limitation of postpartum haemorrhage is suggested., (2010 Elsevier Ltd. All rights reserved.)

Current methods of crystalloid preload administration prior to spinal anaesthesia for elective caesarean section are relatively ineffective in preventing hypotension. This study examined the relevance of the timing of the fluid administered. Fifty women were randomly allocated to receive either 20 ml x kg(-1) of crystalloid solution during 20 minutes prior to induction of spinal anaesthesia (preload), or an equivalent volume by rapid infusion immediately after induction (coload). Significantly more patients in the coload group did not require vasopressor therapy pre-delivery (P=0.047). The coload group required a lower median dose (P=0.03) and a lower median number (P=0.04) of ephedrine doses for the treatment of maternal hypotension pre-delivery. There was no between-group difference in either the total cumulative dose, or in the total number of doses of ephedrine. Neonatal outcomes among the two groups were similar. Rapid crystalloid administration after, rather than over 20 minutes before the induction of spinal anaesthesia for elective caesarean section, may be advantageous in terms of managing maternal blood pressure prior to delivery.

Spinal anaesthesia is the method of choice for caesarean section. There is however a significant associated morbidity and mortality in South Africa, particularly in inexperienced hands. This review provides recommendations for safe practice for anaesthetists at all levels of expertise, with particular reference to the management of haemodynamic instability.

Background: The ease of administration and relative safety of spinal anaesthesia have made this the preferred technique for both elective and many emergency caesarean sections. Complications include incomplete sensory block, resulting in intraoperative breakthrough pain, which is commonly associated with a successful medicolegal claim. If documentation of the spinal anaesthesia technique was found to be inadequate during the course of the medicolegal proceedings, it is likely that the decision would be against the anaesthetist. The purpose of this study was to evaluate documentation by anaesthetists relating to the establishment of surgical anaesthesia utilising subarachnoid block. Methods: A retrospective folder analysis was conducted at Mowbray Maternity Hospital in Cape Town, South Africa. One hundred consecutive spinal anaesthesia charts, each completed by a different anaesthetist, either a registrar or specialist, were analysed. Starting from 31 December 2018 and proceeding retrospectively in time, charts were included until the desired sample size was achieved. Results: Of the 100 cases of spinal anaesthesia for caesarean section analysed, 68 were emergency and 32 were elective operations. Following a literature review, 12 variables were identified that required documentation so that adequate information would be available in the event of medicolegal action. Of these variables, 7 and 8 were recorded in 23% and 32% of the charts, respectively. Ninety per cent of the anaesthesia charts had inadequate documentation, defined as information on fewer than 10 of the specified variables. Conclusion: The quality of documentation of both the procedure and block level during spinal anaesthesia for caesarean section was inadequate. National guidelines should be drafted and standardised to improve the quality of these records, both for quality of care and medicolegal purposes. [ABSTRACT FROM AUTHOR]

Background: In Africa, maternal mortality after caesarean delivery is 50 times greater than in high-income countries. In South Africa, more than 50% of anaesthesia-related maternal mortality is attributed to failure to protect the airway. We implemented an obstetric airway management registry, to facilitate future improvements in management and outcomes. Methods: A prospective electronic registry was established at three obstetric sites in Cape Town, recording airway management for all general anaesthetics from 20 weeks gestation to seven days post-partum. Perioperative descriptive data are entered using a web-based smartphone-enabled platform. To quantify the reliability of capture, we compared the first 200 records in the registry to theatre logbooks. We used summary statistics to describe our obstetric anaesthesia population, and details relevant to airway management. Results: The first 200 cases were recorded from September 2018 to January 2019. According to theatre logbooks, this represented 80% of cases performed. Major indications for general anaesthesia included severe fetal distress/bradycardia (21%), failed neuraxial technique (19%), coagulopathy (19%), and abnormal placentation (12%). A third of patients had hypertensive disorders of pregnancy, and 6% had imminent/confirmed eclampsia. Forty per cent were in active labour. On airway assessment, Mallampati grade was 3 or 4 in 29% of patients, and mouth opening, thyromental distance and mandibular protrusion limited in 10%, 8% and 8% respectively. Cormack-Lehane grade IIb and III views were encountered in 6% and 2% respectively, with no grade IV views. Desaturation below 90% occurred in 12% of patients. There were two cases (1%) of failed intubation with supraglottic airway rescue, and no emergency surgical airways performed. Conclusion: An obstetric airway management registry was successfully implemented. Clinically significant hypoxaemia occurred commonly during general anaesthesia, with a high incidence of difficult intubation predictors and desaturation. The registry will guide research aimed at improving safety during general anaesthesia in obstetrics. [ABSTRACT FROM AUTHOR]

Background: Anaesthesia for caesarean section (CS) in women with eclampsia is a major clinical challenge, and there are limited data concerning the rationale for the choice of technique, and short-term outcomes. A retrospective audit was performed on practice at a tertiary referral centre in Cape Town. Methods: The primary outcome of the audit was the proportion of patients with eclampsia receiving either spinal anaesthesia (SA) or general anaesthesia (GA) for CS, and an assessment of the rationale for the choice of method. In addition, short-term maternal and neonatal outcomes were recorded. Results: There were 11 exclusions in 100 patient records screened, therefore 89 were analysed. Seven/89 (7.9%) patients received SA and 82/89 (92.1%) GA. Overall, 63/89 (70.8%) patients had a preoperative GCS < 14, and 26/89 (29.2%) ≥ 14. Seven/26 patients with GCS ≥ 14 had SA; the remaining 19/26 received GA. GA was performed because there was no platelet count available in three, pulmonary oedema in two, difficult airway due to a bitten tongue in two, fetal bradycardia in two, HELLP syndrome in one, renal failure in one, and patient refusal in one patient. In seven women, there was no clear reason for GA. Median (IQR) Apgar scores at 1 minute in SA patients (8 [8-9]) were higher than those in GA patients with GCS ≥ 14 (5 [3-6]) and < 14 (4 [2-6]), p = .008 and .001 respectively. At five minutes, neonates of SA patients had median scores of 10 [9-10], compared with 8 [7-8] in those of GA patients with GCS ≥ 14, and 8 [7-9] in those with GCS < 14, p = .007 and .019 respectively. There were two stillbirths and two neonatal deaths in the GA group. Patients with GCS ≥ 14 receiving GA required mechanical ventilation for 0 [0-1] days, and those with GCS < 14 were ventilated for 1 [1-2] days. No patients receiving SA required postoperative ventilation, compared with 5/19 (26.3%) patients with GCS ≥ 14 who received GA. Seven/63 patients with GCS < 14 had cerebral oedema, and two had a cerebral infarct. There were two maternal deaths. Conclusions: The small percentage of women with eclampsia who received SA for CS, experienced good maternal and fetal outcomes, and more patients could have safely received SA. Larger prospective audits in high- and low-resource environments are required to establish factors influencing the context-sensitive choice of method of anaesthesia, and risk versus benefit of GA versus SA for CS in women with eclampsia. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented which focuses on the association of ST depression incidence and oxytocin dosage for women who had undergone caesarian delivery.