Butorphanol Mitigates Emergence Agitation in Patients Undergoing Functional Endoscopic Sinus Surgery: A Randomised Controlled Clinical Trail

Background: This study explored the effectiveness of preoperative intravenous injection of butorphanol in the alleviation of emergence agitation (EA) in patients undergoing functional endoscopic sinus surgery (FESS).Methods: Patients (n = 708) were randomized into two groups. The butorphanol group (Group B, n=358) received butorphanol infusion (20 ug/kg) before anaesthesia induction, while the control group (Group C, n=350) received an equal volume of normal saline infusion. General anaesthesia was induced with sufentanil, propofol and rocuronium, and was maintained with sevoflurane and remifentanil. Vasoactive drugs maintained the haemodynamic indices within 20% of the baseline.Results: The incidence of EA (Group B vs. C: 24.3 vs. 31.4%, P = 0.034). The times to spontaneous breathing (26.5 min vs. 23.7 min, P = 0.011), verbal response (36.0 min vs. 33.4 min, P = 0.012) and extubation (31.0 min vs. 28.7 min, P = 0.025) were longer in Group B, and the grade of cough (0.33 vs. 0.43, P = 0.024) at extubation in Group B was lower than that in Group C (P = 0.024). The mean arterial pressure at the end of the operation (P = 0.004) and at 5 min after extubation (P = 0.008) was higher and hypotension was less prominent (0.6% vs. 2.6%, P = 0.030) in Group B.Conclusions: Preoperative intravenous injection of butorphanol decreased the incidence of EA after FESS, and provided smooth and haemodynamically stable emergence without extending the stay in post-anaesthesia care unit.Trial registration: Clinicaltrials.gov, NCT03398759. Registered 21 December 2017, https://www.clinicaltrials.gov/ct2/show/NCT03398759?term=03398759&draw=2&rank=1