Rapid Sequence Induction And Intubation With A Divided Dose Of Mivacurium Compared With Rocuronium: A Randomized, Controlled, Noninferiority Trial

Background: ː Mivacurium is a short-acting nondepolarizing neuromuscular blocking agent (NMBA) with rapid and reliable metabolism. The aim of the present study was to investigate whether mivacurium provided tracheal intubation conditions noninferior to those of rocuronium for rapid sequence induction and intubation in patients undergoing general anesthesia. Methods: ː A total of 158 patients receiving elective surgery were recruited and randomized to the mivacurium group (Group Miva, n=79) or rocuronium group (Group Rocu, n=79). Mivacurium 0.25 mg/kg in divided doses or rocuronium 0.9 mg/kg were given to the patients in Group Miva or Group Rocu, respectively, in combination with propofol, lidocaine, remifentanil, and ephedrine. The primary outcome was the rate of excellent tracheal intubation condition evaluated by Cooper’s scale 90 seconds after the initial dose of NMBAs. The secondary endpoints were mean arterial pressure and heart rate before and 10 minutes after induction at 1-minute intervals and adverse events. The non-inferiority margin was set as 10%. Results: ː The rates of excellent tracheal intubation conditions were 94.94% (75/79) in Group Miva and 100% (79/79) in Group Rocu. The difference was -5.06% (one-sided 97.5% confidence interval -9.96% to -∞), which satisfied the noninferiority hypothesis (P=0.024). Intubating conditions were clinically acceptable in all patients. Mean arterial pressure and heart rate were not significantly different during the induction period (P>0.05). Conclusions: ː Compared with rocuronium 0.9 mg/kg, mivacurium 0.25 mg/kg in divided doses in rapid sequence induction demonstrated noninferiority with regard to the rate of excellent intubation conditions and provided hemodynamic variations comparable to rocuronium. Trial registrationː This study was registered with the Chinese Clinical Trial Registry on 02/05/2020 (URL: http://www.chictr.org.cn. Registry number: ChiCTR2000032571).