Comparison of Ondansetron and Droperidol in Reducing Postoperative Nausea and Sedation Associated with Patient-Controlled Analgesia

Background : To know the effect of droperidol and ondansetron on nausea and sedation in postoperative patients, we studied 120 gynecological patients receiving patient-controlled analgesia (PCA) with morphine and droperidol or ondansetron. Methods : Subjects were randomly allocated to one of four groups according to PCA regimen, morphine 0.5 mg/cc alone(group M); morphine plus droperidol 0.034 mg/morphine 1 mg(group D); morphine plus ondansetron 0.132 mg/morphine 1 mg(group O1); morphine plus ondansetron 0.066 mg/morphine 1 mg (group O2). The PCA device, WalkMed was set at basal rate 2 ml/hr(1 mg/hr), bolus dose 1 ml(0.5 mg), lockout time 10min, 1 hour maximum dose 4 mg. The severity of nausea, sedation and pain were assessed at 1h, 4h, 8h, 12h, 24h, and 48h postoperatively. Results : The occurrence of nausea was not different among groups. But there were statistical differences in the nausea severity(p＜0.05). The group D and group O1 had lower nausea scores, and between them there was no difference. The scores for sedation were significantly lower in the group O1 compared with group M and group D(p＜0.05). Overall pain scores were not different among groups. Conclusions : Ondansetron and droperidol are effective in reducing nausea. Ondansetron is superior to droperidol in avoiding excessive sedation. (Korean J Anesthesiol 1997; 33: 1164∼1169)