Patient-controlled antiemesis: a randomized, double-blind comparison of two doses of propofol versus placebo.

BACKGROUND: The role of propofol for the management of postoperative nausea and vomiting (PONV) is not well established. This study determines the efficacy of small doses of propofol administered by patient-controlled device for the treatment of PONV. METHODS: Patients presenting for ambulatory surgery received a standardized general anesthetic. Those who experienced significant nausea or emesis within 1 h of arrival in the recovery room were randomized to receive repeated doses of propofol 20 mg (P-20), propofol 40 mg (P-40), or intralipid (placebo) on demand. Study medications (in equal volumes) were administered with a patient-controlled delivery device for 2 h. A lockout interval of 5 min between doses was used. The following parameters were assessed: nausea, vomiting, rescue antiemetic use, recovery profile, study drug administration history, and satisfaction with treatment. RESULTS: Sixty-nine patients participated in the study. Patient demographics were similar. The average nausea score for a patient in the P-20 and P-40 groups was 25% and 29% less, respectively, compared with placebo during the study period (P < 0.05). This difference was apparent 15 min after initiation of therapy. More placebo patients vomited (P-20, 12%; P-40, 23%; placebo, 56%; P = 0.003) and needed rescue antiemetics (P-20, 17%; P-40, 23%; placebo, 70%; P = 0.001) compared with treatment groups. Sedation scores were similar between groups. Propofol-treated patients had shorter stays in the post-anesthesia care unit (PACU; P-20, 131+/-35 min [mean +/- SD]; P-40, 141+/-34 min; placebo, 191+/-92 min; P = 0.005) and higher satisfaction with their control of PONV than placebo (P < 0.01). CONCLUSIONS: Propofol is effective in managing PONV with shorter PACU stay and great degree of patient satisfaction. There were two episodes of oversedation in the P-40 group. Hence, propofol at a demand dose of 20 mg seems more appropriate.