Kim HJ, Kim MS, Kim HY, et al. - Researchers conducted this prospective, double-blind, randomized controlled trial to compare the risk of postoperative nausea and vomiting (PONV) based on the timing of fentanyl administration at the end of tonsillectomy in children. One hundred forty patients aged between 3 and 7 years who had tonsillectomy were divided into two groups. Fentanyl (1 μg/kg) was administered in group 1 (n = 70) at the end of the surgery, and in group 2 (n = 70) at 10 to 15 minutes before the end of surgery. From the end of the surgery, time to regular breathing and time to emergence from anesthesia were measured. Between the two groups, incidences of PONV and emergence delirium were not significantly different. In group 1, the time for regular breathing and the time for emergence was significantly longer than in group 2. Though there was no beneficial effect on PONV, with earlier administration of fentanyl, recovery of regular breathing and consciousness was faster. It was concluded that emergence delirium was well-controlled, comparable to that with fentanyl administration at the end of surgery.