INCIDENCE OF NAUSEA AND VOMITING IN OUTPATIENTS UNDERGOING GENERAL-ANESTHESIA IN RELATION TO SELECTION OF INTRAOPERATIVE OPIOID

Study Objective: To measure the incidence of nausea and vomiting in ou tpatients in relation in selection of, or withholding of, intraoperati ve opioid. Design: Prospective, randomized, double-blind control trial . Setting: University general hospital. Patients: 200 unpremedicated A SA status 1 and 11 patients, 8 to 80 years old, under-going general an esthesia for ambulatory surgery. Intervention: Patients were randomize d to four groups, three of which received equipotent doses of differen t opioids intravenously (IV) during induction of anesthesia. Group 1 r eceived nalbuphine 0.25 mg/kg, Group 2, alfentanil 20 ug/kg; Group 3, fentanyl 2 ug/kg; and Group 4, normal saline. Measurements and Main Re sults: We evaluated (1) incidence and severity of nausea and vomiting in the postanesthesia care unit (PACU) and over the next 24 hours; (2) time to PACU discharge; (3) need for antiemetic therapy; and (4) need for analgesic rescue in the PACU. The incidences of nausea and vomiti ng were similar in all groups, as were time to discharge, antiemetic, and nonsteroidal antiinflammatory drug requirements. The highest incid ences of nausea and vomiting occurred at 6 hours in all groups (23% an d 9.5%, respectively). Group 1 required lower rescue doses of morphine in the PACU but this result may have been an artifact due to employin g the mixed agonist-antagonist opioid, nalbuphine, in this group. Conc lusions: Opioid administration at the doses employed during induction of anesthesia does not promote postoperative nausea or vomiting, nor i ncrease length of stay in the PACU.