TRANSDERMAL SCOPOLAMINE FOR THE REDUCTION OF POSTOPERATIVE NAUSEA IN OUTPATIENT EAR SURGERY - A DOUBLE-BLIND, RANDOMIZED STUDY

We evaluated the effect of transdermal scopolamine on the incidence of postoperative nausea and vertigo after outpatient ear surgery (explor atory tympanotomy, mastoidectomy, or endolymphatic sac and oval and ro und window surgery) in a double-blind, placebo-controlled study. A tra nsdermal patch containing either scopolamine (n = 19) or placebo (n = 20) was placed behind the nonsurgical ear 2 h before surgery. Anesthes ia was induced with thiopental (4-6 mg/kg intravenously [IV]), sufenta nil (0.5 mu g/kg IV), and vecuronium (0.1 mg/kg IV) and maintained wit h isoflurane (0.2%-2%) and nitrous oxide (70%) in oxygen. Patients wer e observed postoperatively in the recovery room and after discharge fo r 72 h. There was no significant difference between groups with respec t to time in recovery room, time to discharge, incidence of in-house n ausea, vomiting, amount of antiemetics required, or postoperative visu al analog scale (VAS) scores while in the hospital. After discharge, t here were lower VAS nausea scores (by repeat measures analysis, P < 0. 05) and a lower reported incidence of nausea (31% vs 62%; P < 0.05) an d vertigo (6.2% vs 25%;P < 0.05) in the active patch group versus the placebo group. There was a higher incidence of dry mouth in the active patch group (44% vs 25%). Seven patients did not complete the study d ue to failure to keep the patch in plate or failure to return the diar y from home; and one patient from the placebo patch group was admitted for uncontrolled nausea and vomiting. The authors concluded that tran sdermaI scopolamine is effective in reducing, but not eliminating, pos toperative nausea and vertigo after discharge in outpatient ear surger y.