Effects of Midazolam on Postoperative Nausea and Vomiting and Discharge Times in Outpatients Undergoing Cancer-Related Surgery

Midazolam, a short-acting benzodiazepine used for preoperative anxiolysis, may also have pharmacologic properties that could further reduce the incidence of postoperative nausea and vomiting (PONV) in high-risk patients when included in a multimodal antiemetic protocol. However, concerns remain that the sedating properties of midazolam will delay discharge after short outpatient procedures. A retrospective data analysis (N = 4,057) investigated effects of midazolam on postoperative antiemetic administration and length of stay following cancer-related outpatient procedures over 15 months. Following initial univariate analysis, a multivariable model adjusting for Apfel score, surgical service, age, length of surgery, and type of anesthesia was created to test these associations. The multivariable analysis demonstrated that midazolam was associated with reduced need for postoperative antiemetic medications (3.2% lower than no-midazolam group; 95% confidence interval = 0.03%-6.0%, P = .032). Furthermore, the multivariable analysis demonstrated no clinically significant effect on postoperative length of stay (7.9 minutes shorter in midazolam group; 95% confidence interval = -20 to 4.4, P = .2). In patients for whom midazolam is not otherwise indicated, evidence is insufficient to warrant midazolam administration solely to prevent PONV. Randomized trials are needed to provide an accurate estimation of the effect size of midazolam for PONV in these patients.