Mongolian Society for Pediatric Cardiology

Anesthesia & Clinical Research

Low Dose Epidural Morphine after Caesarian Section as Effective as Standard Dose: A Randomized Controlled Trial

Abstract

Author(s): Rita Araujo* , David Fernandes, Joana Alves, Mariana Rodrigues, Miguel Ferreira, Paulo Muchacho, Pedro Antunes, Filipa Lanca

Aim: The authors aim to place 1 mg as a standard dose for analgesia after caesarian section.

Background: The anesthesiologist is responsible for an effective analgesia after caesarian section, contributing to the well-being of the mother and the minimization of postoperative complications, such as venous thromboembolism, through implementation of early ambulation. The main purpose of this paper is to point out the evidence of effectiveness in postoperative pain control of elective or urgent caesarian section, with confirmation of lower incidence of adverse effects, using a dose of epidural morphine never tested to date, which is 1/3 of the standard dose used in most centers.

Materials and methods: 50 term parturients undergoing cesarean delivery under epidural anesthesia were enrolled in this study. Patients were randomly allocated to receive either 3 mg or 1 mg epidural morphine. In addition, subjects received regular systemic ketorolac and acetaminophen. Rescue analgesia (iv metamizole) was administered for breakthrough pain. Pain intensity at rest using a verbal response scale (VRS 0-10) was regularly assessed for 48 hours. The primary outcome was pain control at rest (VRS<4/10) 24 hours post-operatively. Secondary outcomes included pain scores at 6, 12 and 48 hours post-operatively (rest/mobilization), incidence of side effects (sedation, nausea/ vomiting, pruritus, urinary retention and ileus) and maternal satisfaction. Statistical analysis was performed with SPSS-statistics for windows (Version 20.0. Armonk, NY: IBM Corp).

Results and discussion: Results showed no significant differences in pain relief at rest within 24 hours. The incidence of nausea, vomiting, pruritus and urinary retention was lower in the 1 mg group and time to recovery of bowel function was shorter. The 1 mg group had higher rates of satisfaction than 3 mg group.

Conclusion: When used as part of a multimodal analgesia regimen, 1 mg epidural morphine provided no inferior post-caesarean section analgesia with fewer adverse effects compared with 3 mg epidural morphine.