Postoperative Analgesia with Meperidine in Cesarean Section Patients

Lee, Won Ju; Lee, Yoon Woo; Yoon, Duck Mi; Chang, Won Sok

Abstract

BACKGROUND: Perioperative noxious stimuli and inflammation may induce peripheral and central sensitization. Together, these changes contribute to the state of postinjury pain hypersensitivity found postoperatively. Preemptive analgesia may prevent nociceptive inputs generated during surgery from sensitizing central neurones and may therefore, reduce postoperative pain. We studied whether or not intravenous meperidine infusion before induction could affect postoperative pain and analgesic consumption when compared with intravenous meperidine infusion at peritoneum closure.
METHODS
Female patients scheduled for cesarean section were randomly assigned to one of two groups for prospective study. Group I (n=10) received intravenous meperidine (0.5 mg/kg) 5 minutes before induction of anesthesia and group II (n=10) received the same treatment at peritoneal closure. Both groups had a continuous infusion of meperidine (5 mg/hr) immediately after intravenous bolus meperidine. Postoperative pain relief was provided with intravenous meperidine from a PCA system (Walkmed , Medex, USA). Postoperative visual analogue pain scores (VAS), meperidine consumption and side effects were examined and compared between the groups for two postoperative days.
RESULTS
At two hours post surgery VAS at rest were below 3 in both groups and were not statistically significant. VAS on motion were slightly higher than VAS at rest in both groups and were not statistically significant. There was no significant difference in meperidine consumption. There were minor side effects such as nausea, somnolence, dizziness and pruritus, but no patients needed any treatment and all of them were satisfied.
CONCLUSION
Preemptive or postincisional intravenous PCA with meperidine was equally effective for postoperative analgesia after cesarean section, with minor side effects. These results suggested that there was no reason for applying preemptive analgesia for cesarean section patients. Further studies will be needed to evaluate preemptive effects of intravenous meperidine or other analgesics in cesarean section patients.