Intubating conditions and time course of rocuronium-induced neuromuscular block in children.

We have investigated the potential of rocuronium 0.6 mg kg-1 (2xED95) and 0.9 mg kg-1 (3xED95) for rapid sequence induction in 100 children, aged 3-7 yr. Intubating conditions with the two different doses of rocuronium were assessed in 70 children (n = 35 in each group) undergoing elective surgery. Intubation was carried out by mimicking rapid sequence induction, and intubation conditions were evaluated according to a standard score. Intubating conditions were good to excellent in all 70 patients investigated (2xED95: excellent 29, good 6; 3xED95: excellent 33, good 2). In another 30 children (n = 15 in each group), we examined the times of rocuronium-induced neuromuscular block using electromyography. Lag time and recovery index did not differ significantly between the two groups (lag time: 37 (SD 12) vs 33 (14) s; recovery index: 9 (3) vs 10 (4) min). Three times the ED95 induced deeper neuromuscular block, 1 min after injection compared with 2xED95 (twitch height: 42 (24) vs 25 (19)%, respectively; P < 0.05). The same was true for onset time (193 (47) vs 118 (23) s; P < 0.01), clinical duration (21 (4) vs 34 (11) min; P < 0.01) and duration to 75% recovery (30 (6) vs 44 (4) min; P < 0.01). By mimicking rapid sequence induction, both doses of rocuronium offered clinically acceptable (good or excellent) intubating conditions.