EFFECT OF TROPISETRON, A 5-HT(3) RECEPTOR ANTAGONIST, ON ANALGESIA AND NAUSEA AFTER INTRATHECAL MORPHINE

We have studied the effect of tropisetron, a 5-HT3-receptor antagonist , on postoperative nausea, vomiting and pain in 54 patients, aged 50-8 3 yr, after major hip or knee surgery. The patients were given subarac hnoid injection of plain 0.5% bupivacaine, mixed with preservative-fre e morphine 0.3 mg, for surgical and postoperative analgesia. In a doub le-blind fashion, either tropisetron 5 mg (1 mg ml-1) or saline 5 ml w as injected i. v. 30 min after spinal administration of bupivacaine an d morphine. The number of patients needing i m. oxycodone for pain rel ief the total number of oxycodone doses or the mean time to the first im. oxycodone administration did not differ significantly between the two groups. The number of patients who became nauseated or vomited dur ing the observation period did not differ significantly between groups . Seventeen patients had nausea and 11 vomited in the tropisetron grou p, compared with 20 and 13, respectively, in the control group during the first 24 h.