['Upper respiratory infections (URI) presage perioperative respiratory complications, but thresholds to cancel surgery vary widely. We hypothesized that autonomically-mediated complications seen during emergence from anesthesia would be predicted by capnometry and reduced with preoperative bronchodilator administration.', 'Afebrile outpatient tertiary-care children (age two months to 18 yr, n = 109) without lung disease or findings, having non-cavitary, non-airway surgery for under three hours, were randomized to bronchodilator premedication vs placebo and had preoperative capnometry. After halothane via mask, laryngeal mask airway, or endotracheal tube, and regional anesthesia as appropriate, patients recovered breathing room air while cough, wheeze, stridor, laryngospasm, and cumulative desaturations were recorded for 15 min.', 'In this specific population, there was no association between adverse events and either URI within six weeks (n = 76) or URI within seven days (n = 21). Neither albuterol nor ipratropium premedication decreased adverse events. Endotracheal intubation was associated with increased emergence desaturations and placebo nebulized saline increased emergence coughing. Neither anesthesiologists nor preoperative capnometry predicted adverse events.'] Does bronchodilator premedication decrease respiratory adverse events in pediatric general anesthesia?