Cisatracurium during halothane and balanced anaesthesia in children

Cisatracurium, 51W89, is one of the ten stereoisomers of Tracrium^® which, unlike atracurium, has been reported to have a lack of histamine mediated cardiovascular effects at doses as high as 8×ED₉₅ in adults. We compared the time-course of neuromuscular effects of 80 μg·kg⁻¹ or 100 μg·kg⁻¹ cisatracurium during N₂O-O₂-halothane or N₂O-O₂-opioid anaesthesia, respectively, in 32 children 2–12 years old. Neuromuscular function was monitored by evoked adductor pollicis EMG. Even-numbered patients ( n =16) were allowed to obtain full spontaneous recovery of neuromuscular function and odd-numbered patients ( n =16) received neostigmine 45 μg·kg⁻¹ together with glycopyrrolate at the time of 25% EMG recovery. Data are expressed as median with 10th to 90th percentile range. Cisatracurium had an onset time (time from administration to maximal effect) of 2.2 (1.7–3.8) or 2.3 (1.8–4.9) min, a clinical duration (time to 25% EMG recovery) of 34 (22–40) or 27 (24–33) min, and a spontaneous 25–75% recovery time (time from 25 to 75% EMG recovery) of 11 (9–13) or 11 (7–12) min during halothane or balanced anaesthesia, respectively (NS). Train-of-four ratio recovered to 0.70 in 2.5 (1.8–3.0) or 3.2 (2.1–4.3) min following neostigmine during halothane or balanced anaesthesia, respectively (NS). Changes in blood pressure or heart rate following cisatracurium were negligible. We regard cisatracurium as a safe and promising intermediate duration muscle relaxant the effects of which can easily be reversed with neostigmine.