ODANSETRON VS DROPERIDOL - TREATMENT OF P OSTOPERATIVE NAUSEA AND VOMITING - COMPARISON OF EFFICIENCY, SIDE-EFFECTS AND ACCEPTANCE IN GYNECOLOGICAL INPATIENTS

Introduction. Ondansetron is more effective than a placebo in treating postoperative nausea and vomiting (PONV), but it has not been proved to be superior to established antiemetics for prophylaxis or therapy. We compared ondansetron vs droperidol for the treatment of PONV. Metho ds. Our prospective, randomized double-blind study was performed betwe en 15 October 1992 and July 1993; it included 271 gynaecological ASA I -III inpatients who had been operated on under general anaesthesia wit h intubation. Patients were excluded if: there was no informed consent ; it was an ambulatory or emergency operation; the patient was pregnan t or breast feeding; allergies were being treated with antihistamines; drug addiction was present or convulsions or Parkinson's disease; any pre- or intraoperative antiemetic medication had been administered. A ll patients wishing an antiemetic and/or suffering from at least one e metic episode during the first 24 h postoperatively received either 8 mg ondansetron or 1.25 mg droperidol from identical 4 ml ampoules intr avenously. The verbal nausea score (1 = none, 2 = mild, 3 = moderate, 4 = severe) was recorded every 30 min for 4 h, then before and 2 h aft er each antiemetic dose. All emetic episodes and the interval between administration and effect were also noted. Patients were interviewed 3 6-48 h postoperatively on subjective effects, side-effects and individ ual acceptance. After oral premedication with diapezam, anaesthesia wa s induced with thiopental, in a few cases with etomidate or propofol. Relaxation was achieved with pancuronium or atracurium and, when indic ated, with succinylcholine. Muscular relaxation was antagonized with n eostigmin and glycopyrrolate. Gastric content was aspirated once after intubation. Anaesthesia was maintained with nitrous oxide/oxygen, enf lurance, halothane or isoflurane and fentanyl up to 0.3 mg. Statistica l evaluation was performed by the unpaired Student's t-test and the Ma nn-Whitney U test. Categoric variables were examined by the chi2 test. Significance was defined as P < 0.05. Results. Of 271 patients, 100 ( 37%) experienced PONV. The groups were statistically comparable with r espect to demographic data, type and duration of operation, emesis rec ord, perioperative uterotonic medication. Twenty patients in the ondan setron group and 27 in the droperidol group received the first antieme tic within 2 h, the other patients up to 17 h after extubation. Nausea scores and emetic episodes were identical before antiemetic medicatio n. The reduction of these parameters after medication was similar. Com plete response over 6 h was 60% in the ondansetron and 68% in the drop eridol group. In both groups the first medication failed in 4 cases du ring the initial 2 h. Twenty of the ondansetron and 16 of the droperid ol patients needed a second dose; among these 2 and 4, respectively, a third ampoule. No rescue medication was necessary over 24 h and a mea n of 1.4 ampoules was administered in both groups. Onset and quality o f emetic action were identical in both groups. It was not possible to evaluate 25 interviews due to linguistic or amnestic problems. Multipl e side-effects were noted frequently. Injection pain was reported sign ificantly more often in the droperidol, pruritus in the ondansetron gr oup. Ninety-three percent of the ondansetron and 85% of the droperidol patients opted for the same drug for future PONV treatment. Conclusio ns. Ondansetron (8 mg) and droperidol (1.25 mg) proved to be equally e ffective when used as a postoperative antiemetic. Both drugs showed si milar side-effects. Due to differences in methods it was difficult to compare our results to those obtained in other studies.