Quality of recovery after intrathecal morphine for elective Caesarean deliveries

Abstract

Background: Recent supply issues with diamorphine have meant a change in practice to use of intrathecal morphine. The Obstetric Anaesthetists’ Association (OAA)1 guidelines state that intrathecal diamorphine or morphine provides adequate analgesia after Caesarean section. They discourage the use of parenteral opioids in women who have received neuraxial opioids, owing to the increased risk of respiratory depression. Other side-effects such as nausea and vomiting and pruritus may differ in severity for each drug. We reviewed the side-effects and adherence to the enhanced recovery pathway in elective deliveries receiving intrathecal morphine. Methods: Prospective data were collected for 50 women undergoing Caesarean section with intrathecal opioid analgesia (fentanyl 15 μg and morphine 100 μg) within a 5-week period. Data were collected at Day 1 and Day 2 postoperatively. These included: pain score, postoperative nausea and vomiting (PONV), pruritus, oral opioid use, anti-emetic use, chlorphenamine use, time spent in recovery, and occurrence of urinary retention. Pain score, nausea and vomiting, and pruritus were recorded using a verbal rating scale (VRS). Results: The majority (56.5%) of patients reported only mild pain, 37% reported moderate to severe pain, but of these most (94.7%) only required 20–40 mg of oral morphine in addition to simple analgesia. In addition, the majority (58.7%) of patients reported no PONV. Meanwhile, 45.7% of patients reported mild pruritus, and 43.5% reported no pruritus. Only three of the 50 women did not follow the enhanced recovery pathway. Two remained as inpatients for monitoring after obstetric haemorrhage, and one for intravenous antibiotics. There was no reported respiratory depression. Time spent in recovery was between 1 and 4 h. Although the reason for prolonged recovery stay was not audited, it was thought that requirement for oxytocin infusion increased recovery stay as the ward did not accept patients on an infusion. Conclusions: Our results show an acceptable side-effect profile after elective Caesarean delivery using intrathecal morphine, with adherence to the current enhanced recovery pathway. We aim to implement updated Caesarean delivery guidelines which include prescription of regular ondansetron and chlorphenamine as required, in conjunction with patient education, to try and reduce the incidence of bothersome PONV and pruritus. 1. Obstetric Anaesthetists’ Association, OAA commentary on alternatives to intrathecal and epidural diamorphine for caesarean section analgesia, 2018. Available from: https://www.oaa-anaes.ac.uk/ui/content/content.aspx?ID=4717