Effect of fentanyl on laryngeal airway patency after sugammadex administration: a randomized controlled trial

PURPOSE: Glottic narrowing after sugammadex administration has been reported in patients managed with supraglottic airway devices (SGAs). The influence of opioids on laryngeal airway patency during neuromuscular recovery in adults remains unclear. We tested the hypothesis that fentanyl attenuates vocal cord angle (VCA) narrowing after sugammadex administration. METHODS: In this randomized controlled trial, 20 adult patients undergoing general anesthesia with SGAs were allocated to receive fentanyl (target effect-site concentration 1.0 ng/ml) or no fentanyl. The primary outcome was the change in VCA before and after sugammadex administration (Δ-VCA). Secondary outcomes included VCA at each time point and respiratory variables. RESULTS: 19 patients were analyzed per protocol. VCA narrowing after sugammadex occurred in all patients in the fentanyl group and in three in the no-fentanyl group. Δ-VCA was significantly greater in the fentanyl group than in the no-fentanyl group (median [IQR]: 23 [8-27] vs. 4 [0-18] degrees; P = 0.022), contrary to the original hypothesis. Tidal volume per body weight and minute ventilation decreased significantly after sugammadex in the fentanyl group. No patients in either group reported pain at emergence. CONCLUSION: In adults managed with SGAs, fentanyl administration was associated with greater VCA narrowing during recovery from neuromuscular blockade with sugammadex. Unnecessary or excessive opioid effect-site concentrations relative to the analgesic requirements might contribute to impaired laryngeal airway patency during emergence.