Effect of sitting position on equal-dose spinal anaesthetic for caesarean section and post-partum tubal ligation.

BACKGROUND: We studied the hypothesis that an equal spinal anaesthetic dose administered in the sitting position to patients undergoing post-partum tubal ligation (PPTL) and caesarean section (CS) would yield similar sensory block characteristics and analgesic efficacy. METHODS: This prospective, non-randomised trial recruited 20 women undergoing PPTL within 48 h of vaginal delivery and 20 undergoing CS. Spinal anaesthesia comprising intrathecal hyperbaric bupivacaine 12 mg and morphine 100 µg was administered at L3/4 with patients sitting. Our primary end point was the maximal dermatomal sensory block (to cold). RESULTS: Baseline demographics were comparable, but PPTL patients had greater parity, with mean ± standard deviation 17.54 ± 11.2 h from delivery to spinal anaesthesia, and shorter duration of surgery, 17.54 ± 11.2 vs. 40.3 ± 15.5 min. Similar maximal sensory blocks (to cold) were achieved in group PPTL vs. CS, T4 (T1-T5) vs. T3 (T1-T5), P = 0.104, in comparable times, 8.6 ± 2.6 vs. 7.6 ± 3.0 min, P = 0.267. PPTL patients had significantly faster two-segment block regression (70.7 ± 23.5 vs. 97.6 ± 23.9 min, P = 0.001) and to T10 (120.8 ± 35.6 vs. 145.1 ± 24.3 min, P = 0.016), with less hypotension (25% vs. 65%, P = 0.025) and phenylephrine (20.0 ± 60.6 µg vs. 120.0 ± 119.6 µg, P = 0.005). CONCLUSION: The same dose of hyperbaric bupivacaine 12 mg and morphine 100 µg administered in the sitting position to both PPTL and CS parturients yielded similar maximal sensory blocks, but PPTL exhibited faster block regression and less hypotension/vasopressor requirement.

Determining competence in performing obstetric combined spinal-epidural procedures in junior anesthesiology residents: results from a cumulative sum analysis.

BACKGROUND: The epidural anesthesia technique is a challenging skill to master. The Accreditation Council for Graduate Medical Education (ACGME) stipulates that anesthesiology residents must complete 40 epidural procedures by the end of junior residency. The rationale is unknown. The aim of this prospective study was to determine the minimum case experience required to demonstrate competence in performing obstetric combined spinal-epidural procedures among junior residents, using an objective statistical tool, the cumulative sum (CUSUM) analysis. METHODS: Twenty-four residents, with no prior experience performing epidurals, sequentially recorded all obstetric combined spinal-epidural procedures as a 'success' or 'failure', based on study criteria. Individual CUSUM graphs were plotted, with acceptable and unacceptable failure rates set at 20% and 35%, respectively. The number of procedural attempts necessary to demonstrate competence was determined. RESULTS: Twenty-four residents (mean (SD) age 29 (2) years) participated in the study. Median (IQR) number of procedures was 78 (66-85), with a median (IQR) success rate of 86% (82-89%). Nineteen of 24 residents required a median (IQR) of 40 (33-50) attempts to demonstrate competence. Five did not achieve procedural competence in the training period. The CUSUM graphs highlighted performance trends that required intervention. CONCLUSION: Competence was achieved by 19/24 residents after the ACGME-required case experience of 40 combined spinal-epidural procedures, based on a predefined acceptable failure rate of 20%. In our experience, CUSUM analysis is useful in monitoring technical performance over time and should be included as an adjunct assessment method for determining procedural competence.

Tracheal intubating conditions using propofol and remifentanil target-controlled infusion: a comparison of remifentanil EC50 for Glidescope and Macintosh.

BACKGROUND AND OBJECTIVE: The combination remifentanil-propofol was used for tracheal intubation without muscle relaxant in patients with anticipated difficult airway. Using a target-controlled infusion, we compared the remifentanil concentrations required for intubation with the Macintosh laryngoscope and the Glidescope, at a constant plasma concentration of propofol without muscle relaxant. METHODS: Sixty ASA I or II patients were randomly assigned to either the Macintosh or Glidescope group (30 per group). A target-controlled infusion of propofol was used to maintain a predetermined effect-site concentration of 3 microg ml. The target concentration of remifentanil for each patient in a group was determined by the response of the previous patient, using increments or decrements of 0.5 ng ml. Intubation was attempted at 4 min following induction to allow for equilibration between the blood and the effect site. The intubation response was graded as successful or failure by the Helbo-Hansen scoring system. The median effective concentration of remifentanil for tracheal intubation was determined using the probit regression model. RESULTS: The median effective concentration of remifentanil required for intubation with the Macintosh laryngoscope was 4.41 ng ml (3.13-5.27; 95% confidence interval) and that of the Glidescope was 5.45 ng ml (4.45-6.45; 95% confidence interval; P = 0.083). There was no difference in the total intubation scores. No patients showed signs of muscle rigidity. Arterial pressures or heart rate did not differ between the groups. CONCLUSION: There is no strong evidence that the target remifentanil concentrations required for adequate intubating conditions differed according to the technique used for intubation in the nonparalysed patient. We did not detect any major complications using this technique for either method.

Exploring the challenges of task-centred training in obstetric anaesthesia in the operating theatre environment.

BACKGROUND: Task-centred learning forms the basis of procedural training in obstetric anaesthesia. We observed that our residents were not building their competence from experiential practice in the operating theatre. We used a broad-based framework to explore the challenges encountered by the residents and clinical supervisors in the learning and teaching of obstetric anaesthesia. METHODS: The study was conducted at the KK Women's and Children's Hospital, Singapore, from 1 December 2016 to 30 June 2017. A semi-structured interview format was used in the focus group and individual interviews. Information collection continued until data saturation was reached. The interviews were analysed and the challenges were identified. Fourteen residents and five clinical supervisors participated in the focus group and individual interviews respectively. FINDINGS: The operating theatre constituted a stressful learning and teaching environment for the participants. Five categories of challenges were identified: (1) clinical conditions, (2) concerns about maternal risk and outcomes, (3) reluctance of the residents to vocalise their learning needs, (4) poor feedback, and (5) lack of opportunities for inter-professional practice. These collective challenges reduced the quality of task-centred learning and the effectiveness of supervisor teaching. We described some strategies to overcome these challenges (dedicated trainee lists, obstetric anaesthesia reflective diary, active mentoring system and in-situ simulation). CONCLUSIONS: Our study described the challenges of obstetric anaesthesia training in the operating theatre environment in an Asian healthcare setting. Research is needed on the influence of supervisors' concern about maternal risks and their teaching behaviours.

Comparison of an equal-dose spinal anesthetic for cesarean section and for post partum tubal ligation.

BACKGROUND: We postulated that a spinal dose of hyperbaric bupivacaine 12 mg and morphine 100 microg administered for cesarean section would yield an equivalent sensory block height and provide sufficient analgesia if administered within 48 h of delivery for postpartum tubal ligation. METHOD: 20 women undergoing postpartum tubal ligation (PPTL) within 48 h of vaginal delivery and 20 undergoing cesarean section (CS) were recruited. Spinal anesthesia was induced with intrathecal hyperbaric bupivacaine 12 mg and morphine 100 microg at L3/4 with patients in the right lateral position. RESULTS: Baseline demographics of groups were comparable, but tubal ligation patients had greater parity, with a mean+/-SD 14.5+/-7.5 h from delivery to spinal anesthesia, and shorter duration of surgery, 21.4+/-7.6 vs. 35.3+/-11.3 min. Maximal sensory block was higher in group CS than PPTL, T2 (T1-T4) vs. T3 (T2-T5), P=0.001; time to reach maximal level did not differ significantly, (6.9+/-3.9 vs. 8.7+/-2.8 min, P=0.091). There was no difference in time for spinal block to recede two segments or to T10, and for motor block recovery to Bromage 2, all P>0.05. More CS patients were hypotensive (80% vs. 45%, P=0.048) and had intraoperative nausea (25% vs. 0%, P=0.047), but mean phenylephrine and ephedrine usage did not differ significantly. CONCLUSION: An equivalent dose of hyperbaric bupivacaine 12 mg and morphine 100 microg for both CS and PPTL resulted in a higher sensory block, more hypotension and nausea in CS patients. The studied regimen might be appropriate for PPTL, but appears excessive for CS.

Ergometrine administration for post-partum haemorrhage in an undiagnosed pre-eclamptic.

We report a case of a parturient who was well antenatally but presented with oliguria following delivery. The possibility of post-partum pre-eclampsia was obscured by simultaneous post-partum haemorrhage. Ergometrine was given and she suffered an eclamptic seizure shortly after. We discuss the diagnostic difficulties presented by simultaneous presentation of post-partum pre-eclampsia and haemorrhage and the likelihood that ergometrine precipitated eclampsia in a patient at risk. While ergometrine is an effective drug for the management of uterine atony, its potential role in precipitating eclampsia must be considered.