PROPHYLACTIC ANTIEMETIC THERAPY WITH PATIENT-CONTROLLED ANALGESIA - ADOUBLE-BLIND, PLACEBO-CONTROLLED COMPARISON OF DROPERIDOL, METOCLOPRAMIDE, AND TROPISETRON

This placebo-controlled, randomized, double-blind trial was designed t o evaluate the efficacy of three prophylactic antiemetic regimens on p ostoperative nausea and vomiting (PONV) during patient-controlled anal gesia (PCA) with morphine. We studied 286 elective surgical patients f or 36 h postoperatively. Group 1 was saline control. In Groups 2 and 3 , metoclopramide or droperidol was administered as an intravenous (TV) bolus and then added to morphine in the PCA device. In Group 4, tropi setron, a long-acting investigational 5-hydroxytryptamine subtype 3 (5 -HT5) antagonist was given as a single TV dose. We assessed the freque ncy and severity of PONV, as well as the need for rescue, frequency of side effects, and overall patient satisfaction. Severity of PONV was measured with a symptom-severity score (STS) which was based on both i ntensity and duration. The average total doses of antiemetics were met oclopramide 53.8 +/- 2.2 mg, droperidol 5.99 +/- 0.3 mg, and tropisetr on 6.1 +/- 0.2 mg. Control patients had a 54% incidence of PONV. Drope ridol reduced both the incidence (P < 0.001) and severity (P < 0.01) o f PONV for the entire 36 h. Tropisetron reduced incidence and severity (P < 0.05), but the effect of the single bolus dose lasted only 18 h. Metoclopramide had a marginally significant effect under these condit ions. Only droperidol decreased the need for rescue medication (P < 0. 01), although rescue with tropisetron was highly effective. Side effec ts and patient satisfaction were comparable among the groups, but pati ents receiving droperidol were sleepier (P < 0.05) than control patien ts and recalled somewhat more anxiety (P = 0.03). When used together w ith morphine PCA, droperidol is a highly effective antiemetic for 36 h . Tropisetron is also effective, but more than one dose is required.