RAPID TRACHEAL INTUBATION WITH ROCURONIUM 0.3 MG/KG

S475 Rapid tracheal intubation can be accomplished by given a single bolus of atracurium following by thiopental timed at the onset of clinical weakness (timing principle) [1]. Since propofol 2.5 mg/kg alone has been used for tracheal intubation [2] and onset time of rocuronium is fast, we studies whether rocuronium (0.3 mg/kg) given 30 seconds before propofol provides satisfactory intubation condition and how this method compares with succinycholine or propofol alone. With institutional approval, 60 ASA I or II patients, undergoing laparoscopic bilateral tubal ligation with clinical normal airways, were consented and divided randomly into three groups (n = 20 each). Midazolam 1-2 mg and fentanyl 50-100 ug were given to all patients 10 - 15 minutes prior to induction. Group A patients received rocuronium 0.3 mg/kg followed in 30 seconds by propofol 2.5 mg/kg. Group B patients received succinycholine 1.0 mg/kg iv after propofol 2.5 mg/kg. Group C patients received propofol 2.5 mg/kg only. Intubation was attempted at 90 seconds after rocuronium was given and at 60 seconds after succinycholine or propofol (in group C) was given. The same anesthesiologist who performed all intubations was unaware of the group assignment. Intubation conditions were graded as: EXCELLENT (easy passage of the tube without coughing or bucking), GOOD (passage of the tube with slight coughing or bucking or both), POOR (passage of the tube with moderate coughing or bucking or both), or IMPOSSIBLE (unable to intubate). Anesthesia was maintained with 70% N2O in O2, propofol infusion and incremental fentanyl. The ulnar nerve was stimulated with train-of-four mode (2 Hz) once every 12 seconds with supramaximal stimuli, and evoked compound EMG of the first interosseous muscle was recorded. Data (Mean +/- SEM) were analyzed by t-test. Intubation conditions were evaluated by the Chi square test. P < 0.05 was considered significant. Excellent intubation conditions were existed in 75%, 90% and 25% of patients in group A, B and C, respectively. (Table 1). Onset time (time to maximal twitch suppression after muscle relaxants) was 213.3 +/- 14.5 and 55.8 +/- 2.5 seconds in group A and B, respectively (P < 0.05). Maximum twitch suppression was 90.6 +/- 1.5% and 100 % in group A and B, respectively (P > 0.05). Only 2 patients who received rocuronium achieved 100% twitch depression. Time to recovery to 25% of control twitch height was 18.3 +/- 1.4 and 7.6 +/- 2.7 minutes in group A and Group B, respectively (P <0.05). Hemodynamic changes during induction/intubation were acceptable in all patients.Table 1Only 55% of patients who received propofol alone had satisfactory (excellent + good) intubation condition at 60 seconds. Adding low dose of rocuronium 0.3mg/kg to propofol (30 seconds before the administration of propofol) provided satisfactory intubation condition similar to succinylcholine. This technique is a reasonable alternative when rapid tracheal intubation is needed but succinylcholine is contraindicated and faster recovery is desired.