[Comparative studies of atracurium and vecuronium for medium-length surgical procedures in infants and young children].

Onset time, intubation condition and recovery time after single bolus injection of atracurium (0.3 mg/kg in body weight less than 10 kg (Group 1), 0.5 mg/kg in body weight greater than 10 kg (Group 2] and vecuronium (0.05 mg/kg in body weight less than 10 kg (Group 3), 0.1 mg/kg in body weight greater than 10 kg (Group 4] were studied in 40 infants and children anaesthetised with halothane. At the end of the onset time (time from the end of the bolus injection of the muscle relaxant until the maximal twitch depression of the m. adductor pollicis) the intubation conditions were judged as good or very good in both groups. The onset time after bolus injection of atracurium (92.5 +/- 31.9 sec in Group 1, 117.0 +/- 25.2 sec in Group 2) was slightly shorter than after vecuronium (135.7 +/- 64.1 sec in Group 3, 123.3 +/- 26.8 sec in Group 4). The duration from the time of injection to 75% recovery of T1 had been longer by using atracurium (45.2 min in Group 1 + 2) than by vecuronium (36.6 min in Group 3, 34.2 min in Group 4). In infants (Group 1 + 3) the recovery time (duration from 25% to 75% recovery of control twitch height) after relaxation with atracurium as well as vecuronium was longer than in children (Group 2 + 4). Neither cardiovascular side effects nor signs of histamine release occurred after the injection of both muscle relaxants at our dosage level. It is concluded that in infants and children atracurium is a real alternative to vecuronium for relaxation for medium long surgical procedures.(ABSTRACT TRUNCATED AT 250 WORDS)