Efficacy and Safety of Intrathecal Morphine for Postoperative Pain Management Following Planned Caesarean Section

Condition(s) studied

Investigational drug(s) / intervention(s)

Intrathecal Morphine: 80 μg preservative-free morphine (0.2 ml) added to a single-shot spinal anaesthesia consisting of 11.5 mg hyperbaric bupivacaine and 10 μg fentanyl

Placebo (Sodium Chloride Injection, 0.9%): 0.2 ml of isotonic sodium chloride added to a single-shot spinal anaesthesia consisting of 11.5 mg hyperbaric bupivacaine and 10 μg fentanyl.

Study summary

The goal of this clinical trial is to learn if morphine added to the spinal anaesthesia can improve postoperative pain treatment for patients undergoing caesarean section, without increasing the risk of serious adverse events in mother and baby.

The main questions it aims to answer are:

* Is the treatment effective in preventing postoperative pain?
* Is the treatment safe for both mother and baby?

Participants will be given a normal spinal anaesthesia with addition of either morphine or sodium chloride (inactive substance). All participants will receive standard postoperative pain treatment, including morphine tablets as needed. Researchers will collect data from the electronic medical record and ask the participants to fill out questionnaires about pain levels and possible side effects.

Eligibility

Primary outcome measure(s)

• Level of pain when mobilising from supine to sitting position within 24 hours — 6, 12, 18 and 24 hours following spinal anaesthesia
  Longitudinal measurements of NRS (0-10) at 6, 12, 18 and 24 hours with most focus on the 24-hour pain level
• Maternal and neonatal serious adverse events — Within 7 days from discharge
  Binary composite outcome: 1. Death of either participant or neonate within 7 days 2. Participants with clinically significant respiratory depression within 24 hours, defined as respiratory depression documented in the electronic medical record, e.g. need for airway management or pharmacological intervention (subjective assessment by treating clinician, validated by 2 investigators) 3. Neonates needing admission to neonatal intensive care unit within 48 hours 4. Hospitalisation of either participant or neonate within 7 days after discharge 5. Participants with severe vomiting or nausea within 24 hours, defined as ≥5 points on the 'Simplified postoperative nausea and vomiting impact scale'63 at any time point (6, 12, 18 and 24 hours)

Trial sites (9)