Inadequate neuraxial anaesthesia in patients undergoing elective caesarean section: a systematic review

Neuraxial anaesthesia is widely utilised for elective caesarean section, but the prevalence of inadequate intra-operative anaesthesia is unclear. We aimed to determine the prevalence of inadequate neuraxial anaesthesia for elective caesarean section; prevalence of conversion from neuraxial anaesthesia to general anaesthesia following inadequate neuraxial anaesthesia; and the effect of mode of anaesthesia. We searched studies reporting inadequate neuraxial anaesthesia that used ≥ ED95 doses (effective dose in 95% of the population) of neuraxial local anaesthetic agents. Our primary outcome was the prevalence of inadequate neuraxial anaesthesia, defined as the need to convert to general anaesthesia; the need to repeat or abandon a planned primary neuraxial technique following incision; unplanned administration of intra-operative analgesia (excluding sedatives); or unplanned epidural drug supplementation. Fifty-four randomised controlled trials were included (3497 patients). The overall prevalence of requirement for supplemental analgesia or anaesthesia was 14.6% (95%CI 13.3–15.9%); 510 out of 3497 patients. The prevalence of general anaesthesia conversion was 2 out of 3497 patients (0.06% (95%CI 0.0–0.2%)). Spinal/combined spinal–epidural anaesthesia was associated with a lower overall prevalence of inadequate neuraxial anaesthesia than epidural anaesthesia (10.2% (95%CI 9.0–11.4%), 278 out of 2732 patients vs. 30.3% (95%CI 26.5–34.5%), 232 out of 765 patients). Further studies are needed to identify risk factors, optimise detection and management strategies and to determine long-term effects of inadequate neuraxial anaesthesia.     

A survey of antenatal and peripartum provision of information on analgesia and anaesthesia

Pregnant women should receive information about what they might expect to experience during their delivery. Despite this, research shows many women are inadequately prepared for anaesthetic interventions during labour. We surveyed 903 postnatal women across 28 Greater London hospitals about: the analgesic and anaesthetic information that they recalled receiving during pregnancy and delivery; their confidence to make decisions on analgesia; and their satisfaction with the analgesia used. Wide variation was observed between hospitals. Overall, 67 of 749 (9.0%) women recalled receiving antenatal information covering all aspects of labour analgesia, and 108 of 889 (12.1%) covering anaesthesia for caesarean section. Regarding intrapartum information, 256 of 415 (61.7%) respondents recalled receiving thorough information before epidural insertion for labour analgesia, and 102 of 370 (27.6%) before anaesthesia for caesarean section. We found that 620 of 903 (68.7%) women felt well enough informed to be confident in their analgesic choices, and 675 of 903 (74.8%) stated that their analgesia was as expected or better. Receiving information verbally, regardless of provider, was the factor most strongly associated with respondents recalling receiving full information: odds ratio (95%CI) for labour analgesia 20.66 (8.98–47.53; p < 0.0001); epidural top-up for caesarean section 5.93 (1.57–22.35; p = 0.01); and general anaesthesia for caesarean section 12.39 (2.18–70.42; p = 0.01). A large proportion of respondents did not recall being fully informed before an anaesthetic intervention. Collaboration with current antenatal service providers, both in promoting information delivery and providing resources to assist with delivery, could improve the quality of information offered and women's retention of that information.     

Association between anaesthetic technique and unplanned admission to intensive care after thoracic lung resection surgery: the second Association of Cardiothoracic Anaesthesia and Critical Care (ACTACC) National Audit

Unplanned intensive care admission is a devastating complication of lung resection and is associated with significantly increased mortality. We carried out a two-year retrospective national multicentre cohort study to investigate the influence of anaesthetic and analgesic technique on the need for unplanned postoperative intensive care admission. All patients undergoing lung resection surgery in 16 thoracic surgical centres in the UK in the calendar years 2013 and 2014 were included. We defined critical care admission as the unplanned need for either tracheal intubation and mechanical ventilation or renal replacement therapy, and sought an association between mode of anaesthesia (total intravenous anaesthesia vs. volatile) and analgesic technique (epidural vs. paravertebral) and need for intensive care admission. A total of 253 out of 11,208 patients undergoing lung resection in the study period had an unplanned admission to intensive care in the postoperative period, giving an incidence of intensive care unit admission of 2.3% (95%CI 2.0–2.6%). Patients who had an unplanned admission to intensive care unit had a higher mortality (29.00% vs. 0.03%, p < 0.001), and hospital length of stay was increased (26 vs. 6 days, p < 0.001). Across univariate, complete case and multiple imputation (multivariate) models, there was a strong and significant effect of both anaesthetic and analgesic technique on the need for intensive care admission. Patients receiving total intravenous anaesthesia (OR 0.50 (95%CI 0.34–0.70)), and patients receiving epidural analgesia (OR 0.56 (95%CI 0.41–0.78)) were less likely to have an unplanned admission to intensive care after thoracic surgery. This large retrospective study suggests a significant effect of both anaesthetic and analgesic technique on outcome in patients undergoing lung resection. We must emphasise that the observed association does not directly imply causation, and suggest that well-conducted, large-scale randomised controlled trials are required to address these fundamental questions.     

Complications associated with paediatric airway management during the COVID-19 pandemic: an international,multicentre, observational study

Respiratory adverse events in adults with COVID-19 undergoing general anaesthesia can be life-threatening. However, there remains a knowledge gap about respiratory adverse events in children with COVID-19. We created an international observational registry to collect airway management outcomes in children with COVID-19 who were having a general anaesthetic. We hypothesised that children with confirmed or suspected COVID-19 would experience more hypoxaemia and complications than those without. Between 3 April 2020 and 1 November 2020, 78 international centres participated. In phase 1, centres collected outcomes on all children (age ≤ 18 y) having a general anaesthetic for 2 consecutive weeks. In phase 2, centres recorded outcomes for children with test-confirmed or suspected COVID-19 (based on symptoms) having a general anaesthetic. We did not study children whose tracheas were already intubated. The primary outcome was the incidence of hypoxaemia during airway management. Secondary outcomes included: incidence of other complications; and first-pass success rate for tracheal intubation. In total, 7896 children were analysed (7567 COVID-19 negative and 329 confirmed or presumed COVID-19 positive). The incidence of hypoxaemia during airway management was greater in children who were COVID-19 positive (24 out of 329 (7%) vs. 214 out of 7567 (3%); OR 2.70 (95%CI 1.70–4.10)). Children who had symptoms of COVID-19 had a higher incidence of hypoxaemia compared with those who were asymptomatic (9 out of 51 (19%) vs. 14 out of 258 (5%), respectively; OR 3.7 (95%CI 1.5–9.1)). Children with confirmed or presumed COVID-19 have an increased risk of hypoxaemia during airway management in conjunction with general anaesthesia.     

Prevention of hypotension after spinal anaesthesia for caesarean section: a systematic review and network meta-analysis of randomised controlled trials

Spinal anaesthesia for caesarean section commonly causes maternal hypotension. This systematic review and network meta-analysis compared methods to prevent hypotension in women receiving spinal anaesthesia for caesarean section. We selected randomised controlled trials that compared an intervention to prevent hypotension with another intervention or inactive control by searching MEDLINE and Embase, Web of Science to December 2018. There was no language restriction. Two reviewers extracted data on trial characteristics, methods and outcomes. We assessed risk of bias for individual trials (Cochrane tool) and quality of evidence (GRADE checklist). We assessed 109 trials (8561 women) and 12 different methods that resulted in 30 direct comparisons. Methods ranked by OR (95%CI) from most effective to least effective were: metaraminol 0.11 (0.04–0.26); norepinephrine 0.13 (0.06–0.28); phenylephrine 0.18 (0.11–0.29); leg compression 0.25 (0.14–0.43); ephedrine 0.28 (0.18–0.43); colloid given before induction of anaesthesia 0.38 (0.24–0.61); angiotensin 2, 0.12 (0.02–0.75); colloid given after induction of anaesthesia 0.52 (0.30–0.90); mephentermine 0.09 (0.01–1.30); crystalloid given after induction of anaesthesia 0.78 (0.46–1.31); and crystalloid given before induction of anaesthesia 1.16 (0.76–1.79). Phenylephrine caused maternal bradycardia compared with control, OR (95%CI) 0.23 (0.07–0.79). Ephedrine lowered umbilical artery pH more than phenylephrine, standardised mean difference (95%CI) 0.78 (0.47–1.49). We conclude that vasopressors should be given to healthy women to prevent hypotension during caesarean section with spinal anaesthesia.     

Decision-to-delivery interval and neonatal outcomes for category-1 caesarean sections during the COVID-19 pandemic

General anaesthesia is known to achieve the shortest decision-to-delivery interval for category-1 caesarean section. We investigated whether the COVID-19 pandemic affected the decision-to delivery interval and influenced neonatal outcomes in patients who underwent category-1 caesarean section. Records of 562 patients who underwent emergency caesarean section between 1 April 2019 and 1 July 2019 in seven UK hospitals (pre-COVID-19 group) were compared with 577 emergency caesarean sections performed during the same period during the COVID-19 pandemic (1 April 2020–1 July 2020) (post-COVID-19 group). Primary outcome measures were: decision-to-delivery interval; number of caesarean sections achieving decision-to-delivery interval < 30 min; and a composite of adverse neonatal outcomes (Apgar 5-min score < 7, umbilical arterial pH < 7.10, neonatal intensive care unit admission and stillbirth). The use of general anaesthesia decreased significantly between the pre- and post-COVID-19 groups (risk ratio 0.48 (95%CI 0.37–0.62); p < 0.0001). Compared with the pre-COVID-19 group, the post-COVID-19 group had an increase in median (IQR [range]) decision-to-delivery interval (26 (18–32 [4–124]) min vs. 27 (20–33 [3–102]) min; p = 0.043) and a decrease in the number of caesarean sections meeting the decision-to-delivery interval target of < 30 min (374/562 (66.5%) vs. 349/577 (60.5%); p = 0.02). The incidence of adverse neonatal outcomes was similar in the pre- and post-COVID-19 groups (140/568 (24.6%) vs. 140/583 (24.0%), respectively; p = 0.85). The small increase in decision-to-delivery interval observed during the COVID-19 pandemic did not adversely affect neonatal outcomes.     

A national cohort study to investigate the association between ethnicity and the provision of care in obstetric anaesthesia in England between 2011 and 2021

There is evidence that ethnic inequalities exist in maternity care in the UK, but those specifically in relation to UK obstetric anaesthetic care have not been investigated before. Using routine national maternity data for England (Hospital Episode Statistics Admitted Patient Care) collected between March 2011 and February 2021, we investigated ethnic differences in obstetric anaesthetic care. Anaesthetic care was identified using OPCS classification of interventions and procedures codes. Ethnic groups were coded according to the hospital episode statistics classifications. Multivariable negative binominal regression was used to model the relationship between ethnicity and obstetric anaesthesia (general and neuraxial anaesthesia) by calculating adjusted incidence ratios for the following: differences in maternal age; geographical residence; deprivation; admission year; number of previous deliveries; and comorbidities. Women giving birth vaginally and by caesarean section were considered separately. For women undergoing elective caesarean births, after adjustment for available confounders, general anaesthesia was 58% more common in Caribbean (black or black British) women (adjusted incidence ratio [95%CI] 1.58 [1.26–1.97]) and 35% more common in African (black or black British) women (1.35 [1.19–1.52]). For women who had emergency caesarean births, general anaesthesia was 10% more common in Caribbean (black or black British) women (1.10 [1.00–1.21]) than British (white) women. For women giving birth vaginally (excluding assisted vaginal births), Bangladeshi (Asian or Asian British), Pakistani (Asian or Asian British) and Caribbean (black or black British) women were, respectively, 24% (0.76 [0.74–0.78]), 15% (0.85 [0.84–0.87]) and 8% (0.92 [0.89–0.94]) less likely than British (white) women to receive neuraxial anaesthesia. This observational study cannot determine the causes for these disparities, which may include unaccounted confounders. Our findings merit further research to investigate potentially remediable factors such as inequality of access to appropriate obstetric anaesthetic care.     

Ultrasound-guided caudal blockade and sedation for paediatric surgery: a retrospective cohort study

Data on safety and success rates of ultrasound-guided caudal blockade, performed on sedated children with an uninstrumented airway, are scarce. We performed a retrospective observational study of validated data from April 2014 to December 2020 in a paediatric cohort where the initial plan for anaesthetic management was sedation and caudal epidural without general anaesthesia or airway instrumentation. We examined success rates of this approach and rates of block failure and block-related complications. In total, 2547 patients ≤ 15 years of chronological age met inclusion criteria. Among the 2547 cases, including 453 (17.8%) former preterm patients, caudal-plus-sedation success rate was 95.1%. The primary anaesthesia plan was abandoned for general anaesthesia in 124 cases. Pain-related block failure in 83 (3.2%) was the most common cause for conversion. Complications included 39 respiratory events and 9 accidental spinal anaesthetics. Higher odds of pain-related block failure were associated with higher body weight (adjusted OR 1.063, 95%CI 1.035–1.092, p < 0.001) as well as with mid-abdominal surgery (e.g. umbilical hernia repair) (adjusted OR 15.11, 95%CI 7.69–29.7, p < 0.001), whereas extreme (< 28 weeks) former prematurity, regardless of chronological age, was associated with higher odds (adjusted OR 3.62, 95%CI 1.38–9.5, p = 0.009) for respiratory problems. Ultrasound-guided caudal epidural, performed under sedation with an uninstrumented airway, is an effective technique in the daily clinical routine. Higher body weight and mid-abdominal surgical procedures are risk factors for pain-related block failure. Patients who, regardless of chronological age, had been born as extreme preterm babies are at the highest risk for respiratory events.     

Obstetric anaesthesia outcome in obese and non-obese parturients undergoing caesarean delivery: an observational study

BackgroundMaternal obesity is increasing in prevalence and is associated with an increased risk of perioperative complications. This study evaluates the impact of obesity on perioperative outcomes in parturients undergoing caesarean delivery.MethodsIn this prospective observational study of 1477 consecutive caesarean deliveries, data collected included body mass index, co-morbidities, anaesthetic technique, perioperative complications and patient satisfaction. Outcome measures included obesity prevalence, association of obesity with caesarean delivery, co-morbidities, perioperative complications and patient satisfaction and were compared between the obese and non-obese groups.ResultsThe prevalence of obesity was 54.3%, including 7.2% morbidly obese. About 61% of parturients who underwent caesarean delivery because of failure to progress in labour or previous caesarean were obese. The overall prevalence of co-morbidity was 10.2% of whom 57.3% were obese. Neuraxial anaesthesia was used in 73.4% and general anaesthesia in 26.6%, similar in obese and non-obese. The epidural failure rate was 4.3% and the spinal failure rate 2.9%. Difficulty in performing neuraxial anaesthesia was greater in obese patients (P = 0.004). There was no association between obesity and laryngoscopy grades. Patient satisfaction was similar in the obese and non-obese groups. Postoperative complications were minimal and similar.ConclusionsNeuraxial anaesthesia was effective for caesarean deliveries in obese and non-obese, in elective and emergency cases. Maternal obesity is associated with increased difficulty in performing neuraxial anaesthesia, but not with increased failure rate. Our study found no differences between obese and non-obese parturients in rate of caesarean deliveries, co-morbidities, indications for delivery or anaesthesia complications.     

Impact of spinal anaesthesia vs. general anaesthesia on peri‐operative outcome in lumbar spine surgery: a systematic review and meta‐analysis of randomised,controlled trials

Lumbar spinal surgery is most commonly performed under general anaesthesia. However, spinal anaesthesia has also been used. We aimed to systematically review the comparative evidence. We only included randomised, controlled trials in this meta‐analysis and calculated the risk ratio or standardised mean difference for haemodynamics, blood loss, surgical time, analgesic requirement, nausea and/or vomiting, and length of hospital stay. Eight studies with a total of 625 patients were included. These were considered to be at high risk of bias. Compared with general anaesthesia, the risk ratio (95% CI ) with spinal anaesthesia for intra‐operative hypertension was 0.31 (0.15–0.64), I² = 0% (p = 0.002); for intra‐operative tachycardia 0.51 (0.30–0.84), I² = 0% (p = 0.009); for analgesic requirement in the postanaesthesia care unit 0.32 (0.24–0.43), I² = 0% (p < 0.0001); and for nausea/vomiting within 24 h postoperatively 0.29 (0.18–0.46), I² = 12% (p < 0.00001). The standardised mean difference (95% CI ) for hospital stay was ?1.15 (?1.98 to ?0.31), I² = 89% (p = 0.007). There was no evidence of a difference in intra‐operative hypotension and bradycardia, blood loss, surgical time, analgesic requirement within 24 h postoperatively, and nausea/vomiting in the postanaesthesia care unit. We conclude that spinal anaesthesia appears to offer advantages over general anaesthesia for lumbar spine surgery.     

Regional anaesthesia for caesarean birth and what to do if it fails

Regional anaesthetic techniques are the most frequently used type of anaesthetic for caesarean births. They have a better safety pro?le than general anaesthesia in the pregnant woman. The choice of whether to use a spinal, epidural or combined spinal–epidural technique will depend on patient and surgical factors. Particular care is required in those receiving therapeutic anticoagulation or with clotting abnormalities. Women should be provided with information regarding the risks and intended bene?ts of the different techniques to make an informed choice regarding mode of anaesthesia. All women having caesarean births must have vital sign monitoring, antacid prophylaxis and intraoperative venous thromboembolic prophylaxis. A left lateral tilt must be maintained until delivery of the baby to reduce the effects of aortocaval compression. Adequate anaesthesia must be con?rmed prior to commencing surgery and strategies for managing failed spinal anaesthesia should be defined in local guidelines. Breakthrough pain during caesarean birth is a distressing complication and must be addressed. General anaesthesia should be offered and, if declined, the woman's pain must be adequately managed with alternative analgesic methods. These include nitrous oxide, opioids and local anaesthetic in?ltration.     

Effects of intra‐operative maintenance of general anaesthesia with propofol on postoperative pain outcomes – a systematic review and meta‐analysis

Propofol is used both for induction and maintenance of anaesthesia. Recent evidence shows that propofol has analgesic properties. This meta‐analysis evaluated differences in postoperative analgesia between general anaesthetic maintenance with intravenous propofol and inhalational anaesthetics. Fourteen trials met inclusion criteria and were included. Our outcomes were pain scores 2 and 24 h after surgery. No significant difference in pain scores was found at 2 h after surgery (Hedge's g (95% CI) ?0.120 (?0.415–0.175) (p = 0.425). Propofol was associated with a statistically significant, albeit marginal, reduction in pain scores 24 h after surgery (Hedge's g (95% CI) ?0.134 (?0.248 to ?0.021) (p = 0.021). Data were insufficient to allow a meaningful analysis regarding 24‐h morphine‐equivalent consumption. Propofol was associated with reduced postoperative nausea and vomiting (relative risk (95%CI) 0.446 (0.304–0.656) (p < 0.0001). In conclusion, this meta‐analysis suggests that propofol improves postoperative analgesia compared with inhalational anaesthesia 24 h after surgery, with a lower incidence of nausea and vomiting.     

Spinal or general anaesthesia for surgical repair of hip fracture and subsequent risk of mortality and morbidity: a database analysis using propensity score-matching

Around 76,000 people fracture their hip annually in the UK at a considerable personal, social and financial cost. Despite longstanding debate, the optimal mode of anaesthesia (general or spinal) remains unclear. Our aim was to assess whether there is a significant difference in mortality and morbidity between patients undergoing spinal anaesthesia compared with general anaesthesia during hip fracture surgery. A secondary analysis examined whether a difference exists in mortality for patients with pre-existing cardiovascular disease or chronic obstructive pulmonary disease. This was a clinical database analysis of patients treated for hip fracture in Nottingham, UK between 2004 and 2015. Propensity score-matching was used to generate matched pairs of patients, one of whom underwent each mode of anaesthesia. Data were analysed using conditional logistic regression, with 7164 patients successfully matched. There was no difference in 30- or 90-day mortality in patients who had spinal rather than general anaesthesia (OR [95%CI] 0.97 [0.8–1.15]; p = 0.764 and 0.93 [0.82–1.05]; p = 0.247 respectively). Patients who had a spinal anaesthetic had a lower-risk of blood transfusion (OR [95%CI] 0.84 [0.75–0.94]; p = 0.003) and urinary tract infection (OR [95%CI] 0.72 [0.61–0.84]; p < 0.001), but were more likely to develop a chest infection (OR [95%CI] 1.23 [1.07–1.42]; p = 0.004), deep vein thrombosis (OR [95%CI] 2.18 [1.07–4.45]; p = 0.032) or pulmonary embolism (OR [95%CI] 2.23 [1.16–4.29]; p = 0.016). The mode of anaesthesia for hip fracture surgery resulted in no significant difference in mortality, but there was a significant difference in several measures of postoperative morbidity.     

Is obstetric epidural anaesthesia technically possible after spinal surgery and does it work?

OBJECTIVE: Previous spine surgery theoretically exposes the obstetric patient to a greater technical difficulty during regional analgesia for labour or during anaesthesia for caesarean delivery. Published experience suggests that epidural puncture is however technically possible in the majority of cases. STUDY DESIGN: Retrospective study. PATIENTS: Analysis of the files of parturients who gave birth in a maternity hospital during a six year period and who had previously undergone spine surgery. METHODS: Technical failures (during puncture), analgesic failures (complete block inefficiency and/or requirement of a general anaesthetic) and complications (important bleeding at the puncture site, dural tap, infection) observed during epidural analgesia/anaesthesia were recorded. RESULTS: Except for two paraplegic parturients who had been operated for dorsocervical traumatic injuries and who were excluded from the analysis, 31 parturients had undergone spine surgery and delivered during the period of analysis. Twenty patients underwent 22 epidural punctures. Technical failure were noted in two cases (9%) and analgesic failure in two other cases (9%). No significant complication was recorded. CONCLUSION: With an overall 18% failure rate, epidural anaesthesia is not contra-indicated in these patients but appears to be less reliable than in patients with normal spine. Psychological and technical preparation to the occurrence of failure is necessary.     

A randomised controlled trial of the effect of a head-elevation pillow on intrathecal local anaesthetic spread in caesarean section

BackgroundA head-elevation pillow places a patient in a ramped posture, which maximises the view of the larynx during laryngoscopy, particularly in obese parturients. In our institution an elevation pillow is used pre-emptively for neuraxial anaesthesia. We hypothesised that head-elevation may impair cephalad spread of local anaesthetic before caesarean section resulting in a lower block or longer time to achieve a T6 level. We aimed to investigate the effect of head-elevation on spread of intrathecal local anaesthetics during anaesthesia for caesarean section.MethodsOne-hundred parturients presenting for caesarean section under combined spinal-epidural anaesthesia were randomised to either the standard supine position with lateral displacement or in the supine position with lateral displacement on an head-elevation pillow. Each patient received intrathecal hyperbaric bupivacaine 11 mg, morphine 100 μg and fentanyl 15 μg. Patients were assessed for adequacy of sensory block (T6 or higher) at 10 min.ResultsSensory block to T6 was achieved within 10 min in 65.9% of parturients in the Elevation Pillow Group compared to 95.7% in the Control Group (P<0.05). Compared to the Control Group, patients in the Elevation Pillow Group had greater requirements for epidural supplementation (43.5% vs 2.1%, P<0.001) or conversion to general anaesthesia (9.3% vs 0%, P<0.04).ConclusionsUse of a ramped position with an head-elevation pillow following injection of the intrathecal component of a combined spinal-epidural anaesthetic for scheduled caesarean section was associated with a significantly lower block height at 10 min.     

A cross-sectional study of immune seroconversion to SARS-CoV-2 in frontline maternity health professionals

COVID-19, the respiratory disease caused by SARS-CoV-2, is thought to cause a milder illness in pregnancy with a greater proportion of asymptomatic carriers. This has important implications for the risk of patient-to-staff, staff-to-staff and staff-to-patient transmission among health professionals in maternity units. The aim of this study was to investigate the prevalence of previously undiagnosed SARS-CoV-2 infection in health professionals from two tertiary-level maternity units in London, UK, and to determine associations between healthcare workers’ characteristics, reported symptoms and serological evidence of prior SARS-CoV-2 infection. In total, 200 anaesthetists, midwives and obstetricians, with no previously confirmed diagnosis of COVID-19, were tested for immune seroconversion using laboratory IgG assays. Comprehensive symptom and medical histories were also collected. Five out of 40 (12.5%; 95%CI 4.2–26.8%) anaesthetists, 7/52 (13.5%; 95%CI 5.6–25.8%) obstetricians and 17/108 (15.7%; 95%CI 9.5–24.0%) midwives were seropositive, with an overall total of 29/200 (14.5%; 95%CI 9.9–20.1%) of maternity healthcare workers testing positive for IgG antibodies against SARS-CoV-2. Of those who had seroconverted, 10/29 (35.5%) were completely asymptomatic. Fever or cough were only present in 6/29 (21%) and 10/29 (35%) respectively. Anosmia was the most common symptom occurring in 15/29 (52%) seropositive participants and was the only symptom that was predictive of positive seroconversion (OR 18; 95%CI 6–55). Of those who were seropositive, 59% had not self-isolated at any point and continued to provide patient care in the hospital setting. This is the largest study of baseline immune seroconversion in maternity healthcare workers conducted to date and reveals that one out of six were seropositive, of whom one out of three were asymptomatic. This has significant implications for the risk of occupational transmission of SARS-CoV-2 for both staff and patients in maternity units. Regular testing of staff, including asymptomatic staff should be considered to reduce transmission risk.     

An observational prospective cohort study of incidence and characteristics of failed spinal anaesthesia for caesarean section

BackgroundA prospective cohort study was performed in 800 parturients undergoing elective caesarean section under spinal anaesthesia from May 2005 to April 2006 in a large maternity hospital in Singapore, in order to determine the incidence of and risk factors for total and partial failure of spinal anaesthesia.MethodsA routine single-shot spinal technique using intrathecal 0.5% heavy bupivacaine 2.0 mL (10 mg) and morphine 100 μg was administered with a 27-gauge Whitacre spinal needle via a 20-gauge introducer. Demographic, surgical and anaesthetic data were collected to determine risk factors for failure of spinal anaesthesia.ResultsIncidence of total failure requiring conversion to general anaesthesia was 0.5% (4 cases) in which three cases had inadequate block (loss of sensation to cold less than T6) and one case had no sensory block. Thirty-three parturients (4.1%) required intravenous fentanyl and seven (0.9%) required Entonox for intraoperative analgesic supplementation. Postpartum sterilization (P < 0.001) was an independent risk factor for partial failure requiring intravenous fentanyl and Entonox.ConclusionSpinal anaesthesia using bupivacaine 10 mg with morphine 100 μg produces reliable anaesthesia for elective caesarean section. Postpartum sterilization involves exteriorisation of the uterus with additional surgical manipulation and hence may necessitate analgesic supplementation. The initial use of a combined spinal-epidural technique or the addition of intrathecal fentanyl or clonidine or an increased dose of local anaesthetic may be considered to decrease the incidence of intraoperative pain.     

Incidence of accidental awareness during general anaesthesia in obstetrics: a multicentre,prospective cohort study

General anaesthesia for obstetric surgery has distinct characteristics that may contribute towards a higher risk of accidental awareness during general anaesthesia. The primary aim of this study was to investigate the incidence, experience and psychological implications of unintended conscious awareness during general anaesthesia in obstetric patients. From May 2017 to August 2018, 3115 consenting patients receiving general anaesthesia for obstetric surgery in 72 hospitals in England were recruited to the study. Patients received three repetitions of standardised questioning over 30 days, with responses indicating memories during general anaesthesia that were verified using interviews and record interrogation. A total of 12 patients had certain/probable or possible awareness, an incidence of 1 in 256 (95%CI 149–500) for all obstetric surgery. The incidence was 1 in 212 (95%CI 122–417) for caesarean section surgery. Distressing experiences were reported by seven (58.3%) patients, paralysis by five (41.7%) and paralysis with pain by two (16.7%). Accidental awareness occurred during induction and emergence in nine (75%) of the patients who reported awareness. Factors associated with accidental awareness during general anaesthesia were: high BMI (25–30 kg.m^-2); low BMI (<18.5 kg.m^-2); out-of-hours surgery; and use of ketamine or thiopental for induction. Standardised psychological impact scores at 30 days were significantly higher in awareness patients (median (IQR [range]) 15 (2.7–52.0 [2–56]) than in patients without awareness 3 (1–9 [0–64]), p = 0.010. Four patients had a provisional diagnosis of post-traumatic stress disorder. We conclude that direct postoperative questioning reveals high rates of accidental awareness during general anaesthesia for obstetric surgery, which has implications for anaesthetic practice, consent and follow-up.     

The predictive ability of non‐invasive haemodynamic parameters for hypotension during caesarean section: a prospective observational study

Spinal anaesthesia for caesarean section induces hypotension, which may cause severe adverse effects. Our goal was to determine whether hypotension could be predicted by pulse oximetry parameters, such as the perfusion index and pleth variability index, heart rate, ratio of low‐frequency to high‐frequency components of heart rate variability, and entropy of heart rate variability, measured before the induction of anaesthesia. The predictive value of these parameters for detecting hypotension was assessed using logistic regression and the grey zone approach in 81 parturients. Logistic regression revealed heart rate to be the only independent predictor (OR 1.06; 95% CI 1.01–1.13; p = 0.032). The grey zone for heart rate was in the range of 71–89 bpm, and 60.5% of parturients were in the grey zone. Pre‐anaesthetic heart rate, but not other parameters derived from pulse oximetry or heart rate variability, may be a prognostic factor for hypotension associated with spinal anaesthesia.     

Operating room‐to‐incision interval and neonatal outcome in emergency caesarean section: a retrospective 5‐year cohort study

We conducted a 5‐year retrospective cohort study on women undergoing caesarean section to investigate factors influencing the operating room‐to‐incision interval. Time‐to‐event analysis was performed for category‐1 caesarean section using a Cox proportional hazards regression model. Covariates included: anaesthetic technique; body mass index; age; parity; time of delivery; and gestational age. Binary logistic regression was performed for 5‐min Apgar score ≥ 7. There were 677 women who underwent category‐1 caesarean section and who met the entry criteria. Unadjusted median (IQR [range]) operating room‐to‐incision intervals were: epidural top‐up 11 (7–17 [0–87]) min; general anaesthesia 6 (4–11 [0–69]) min; spinal 13 (10–20 [0–83]) min; and combined spinal‐epidural 24 (13–35 [0–75]) min. Cox regression showed general anaesthesia to be the most rapid method with a hazard ratio (95%CI) of 1.97 (1.60–2.44; p < 0.0001), followed by epidural top‐up (reference group), spinal anaesthesia 0.79 (0.65–0.96; p = 0.02) and combined spinal‐epidural 0.48 (0.35–0.67; p < 0.0001). Underweight and overweight body mass indexes were associated with longer operating room‐to‐incision intervals. General anaesthesia was associated with fewer 5‐min Apgar scores ≥ 7 with an odds ratio (95%CI) of 0.28 (0.11–0.68; p < 0.01). There was no difference in neonatal outcomes between the first and fifth quintiles for operating room‐to‐incision intervals. General anaesthesia is associated with the most rapid operating room‐to‐incision interval for category‐1 caesarean section, but is also associated with worse short term neonatal outcomes. Longer operating room‐to‐incision intervals were not associated with worse neonatal outcomes.