Background: Various opioids have been recommended for spinal anaesthesia during Caesarean section. The aim of this prospective randomized, double-blind study was to compare the quality of postoperative analgesia and adverse effects after intrathecal administration of 0.5% hyperbaric bupivacaine (HB) combined with either morphine or fentanyl.
Methods: Sixty parturients were randomly allocated to receive intrathecally, 7.5-15 mg of HB with either 25 microg fentanyl (group F), or 100 microg morphine (group M). All women received 100 mg ketoprofen at 2 and 14 h after surgery, and 1.0 g paracetamol at 2, 8, 14 and 20 h after surgery. Additionally, meperidine was offered as a rescue analgesic via patient-controlled analgesia (PCA). During the first 24 h after surgery, pain intensity was evaluated using a VAS score, meperidine consumption was noted, and possible side effects were assessed.
Results: Mean PCA meperidine consumption was 47 mg and 130 mg, for groups M and F, respectively. Intrathecal morphine significantly prolonged the time to first PCA use, when compared to fentanyl. The mean VAS score was lower in group M. Pruritus was more frequently observed in group M. There was no significant difference in the incidence of postoperative nausea and vomiting between both groups.
Conclusions: Both intrathecal morphine and fentanyl significantly reduced the intensity of postoperative pain. Morphine increased the duration of postoperative analgesia and reduced the demand for rescue meperidine.