Effect of Propofol Infusion on Need for Rescue Antiemetics in Postanesthesia Care Unit After Volatile Anesthesia: A Retrospective Cohort Study

BACKGROUND: Postoperative nausea and vomiting (PONV) are frequent after volatile anesthesia. We hypothesized that coadministration of propofol with volatile anesthetic compared to pure volatile anesthetics would decrease the need for postoperative antiemetic treatments and shorten recovery time in the postanesthesia care unit (PACU). METHODS: We retrospectively identified adult patients who underwent procedures using general anesthesia with volatile agents, with or without propofol infusion, from May 2018 through December 2020, and who were admitted to the PACU. Inverse probability of treatment weighting (IPTW) analysis was performed using generalized estimating equations with robust variance estimates to assess whether propofol was associated with decreased need for rescue antiemetics. RESULTS: Among 47,847 patients, overall IPTW rescue antiemetic use was 4.7% for 17,573 patients who received propofol and 8.2% for 30,274 who did not (odds ratio [OR], 0.55; 95% confidence interval [CI], 0.49–0.61; P <.001). This effect associated with propofol was present regardless of the intensity of antiemetic prophylaxis (OR, 0.59, 0.51, and 0.58 for 0–1, 2, and ≥3 antiemetics used, respectively), procedural duration (OR, 0.54, 0.62, and 0.47 for ≤2.50, 2.51–4.00, ≥4.01 hours), and type of volatile agent (OR, 0.51, 0.52, and 0.57 for desflurane, isoflurane, and sevoflurane) (all P <.001). This effect was dose dependent, with little additional benefit for the reduction in the use of PACU antiemetics when propofol rate exceeded 100 μg/kg/min. Patients who received rescue antiemetics required longer PACU recovery time than those who did not receive antiemetics (ratio of the geometric mean, 1.31; 95% CI, 1.28–1.33; P <.001), but use of propofol did not affect PACU recovery time (ratio of the geometric mean, 1.00; 95% CI, 0.98–1.01; P =.56). CONCLUSIONS: The addition of propofol infusions to volatile-based anesthesia is associated with a dose-dependent reduction in the need for rescue antiemetics in the PACU regardless of the number of prophylactic antiemetics, duration of procedure, and type of volatile agent used, without affecting PACU recovery time.