The Effect of a Transdermal Scopolamine Patch on Postoperative Nausea and Vomiting after Retromastoid Craniectomy with Microvascular Decompression: A Preliminary Single Center, Double-Blind, Randomized Controlled Trial

Abstract

<b>Background:</b> We performed this prospective double-blind randomized controlled trial to identify the effect of a preoperative prophylactic transdermal scopolamine (TDS) patch on postoperative nausea and vomiting (PONV) after retromastoid craniectomy with microvascular decompression (RMC-MVD). <b>Methods:</b> We recruited 38 patients undergoing RMC-MVD and randomized them into two groups: the TDS group (<i>n</i> = 19, application of the TDS patch) and placebo group (<i>n</i> = 19, application of a sham patch). Nausea (as a self-reported 100-mm visual analog scale (VAS) score; range, 0 (no nausea) to 10 (worst nausea)), vomiting, and the use of antiemetics were the primary endpoints. <b>Results:</b> There was no significant difference in terms of the incidence of PONV (73.7% in the TDS group and 78.9% in the placebo group; <i>p</i> = 1.00) between the groups. However, the mean nausea VAS score was significantly different at arrival to the general ward (0.93 ± 1.71 in the TDS group vs. 2.52 ± 2.85 in the placebo group; p = 0.046), and throughout the study period (0.03 ± 0.07 in the TDS group vs. 0.44 ± 0.71 in the placebo group; p = 0.029). Rescue antiemetics were more frequently used in the placebo group than in the TDS group (9 (47.4%) vs. 2 (10.5%), respectively; <i>p</i> = 0.029). The mean number of antiemetics used throughout the study period was significantly higher in the placebo group than in the TDS group (1.37 ± 2.19 vs. 0.16 ± 0.50, respectively; p = 0.029). <b>Conclusions:</b> The preoperative prophylactic use of a TDS patch was safe and effective in the management of PONV after RMC-MVD in terms of the severity of PONV and the use of rescue antiemetics.