Effectiveness and safety of rocuronium-hypnotic sequence for rapid-sequence induction.

BACKGROUND

Either succinylcholine or rocuronium administered after a hypnotic is the current technique for rapid-sequence induction. It is assumed that rocuronium administered before a hypnotic (Rocuronium-hypnotic sequence) may equally provide an acceptable intubation condition as well as a shorter period of apnea in rapid-sequence induction. We designed a prospective, randomized study to evaluate the effectiveness and safety of the technique in a similar rapid-sequence induction.

METHODS

Ninety adult patients receiving elective surgeries were enrolled in this study. In all patients the procedure in the study began with i.v. injection of fentanyl 2 micrograms/kg, followed by preoxygenation with 100% O2 for 2 min. Afterward, the patients were randomly allocated to 3 groups with each group consisting of 30 patients. In Rocuronium-thiopental (Ro-Th) group the patients received rocuronium 0.6 mg/kg and then thiopental 5 mg/kg; in Th-Ro group the patients received thiopental 5 mg/kg and then rocuronium 0.6 mg/kg; and in Thiopental-Succinylcholine (Th-Sx) group, the control group, the patients received thiopental 5 mg/kg and then succinylcholine 1 mg/kg. Laryngoscopy and endotracheal intubation were performed 60 s after the injection of the muscle relaxant. The intubation condition, the apneal time before laryngoscopy, the intubation time, and total apneal time were investigated and compared. Presence of injection pain, sense of paralysis, SpO2 less than 95% during induction, and any unexpected adverse event were also recorded.

RESULTS

Six patients (1 in Ro-Th group, 2 in Th-Ro group, and 3 in Th-Sx group, respectively) were excluded from the study. The intubation conditions were acceptable in all patients of three groups who completed the study, and as to excellent intubation condition there was no difference between the three groups. In Ro-Th group both the apneal time before laryngoscopy (32.4 +/- 5.4 s) and total apneal time (48.5 +/- 11.0 s) were the shortest. Th-Ro group (53.2 +/- 5.8 and 67.5 +/- 8.3 s, respectively) and Th-Sx group (54.4 +/- 5.8 and 68.4 +/- 7.7 s, respectively) were similar in both aspects. With respect to intubation time there was no significant difference among the three groups. Five patients in Ro-Th group and one patient in Th-Sx group felt mild injection pain. Three patients in Ro-Th group were noted to have diminished breathing during induction, which was not recalled during enquiry in the postoperative visit. One patient in Ro-Th group saw a fall of SpO2 down below 95% (94% the minimal) during the apnea period.

CONCLUSIONS

Compared with traditional hypnotic-rocuronium or hypnotic-succinylcholine sequence, rocuronium (0.6 mg)-thiopental sequence can provide a similar intubation condition but cause a much shorter apneal period in rapid-sequence induction. In carrying out recuronium-thiopental sequence induction, maintaining a patent infusion line is essential to avoid drug precipitation and awareness of muscular weakness as a result of ill-timed action of thiopental.