Edrophonium Antagonism of Cisatracurium-Induced Neuromuscular Block: Dose Requirements in Children and Adults

Abstract

This randomized, controlled study compared edrophonium dose requirements to antagonize cisatracurium-induced neuromuscular block in children and adults. Sixty children, aged two to 10 years, and 60 adults aged 20 to 60 years, all subjects ASA physical status 1 or 2, having propofol, fentanyl and isoflurane-N 2 O anaesthesia, were studied. Cisatracurium 0.1 mg.kg -1 was given for muscle relaxation. Neuromuscular block was monitored with accelerometry. Edrophonium 0.1, 0.2, 0.4 or 1 mg.kg -1 or no anticholinesterase (controls) was given by random allocation to antagonize 90% neuromuscular block in each of the study groups (n=12). Atropine 5 to 10 μg.kg -1 was given according to edrophonium dose. Onset time of cisatracurium-induced block in children was mean (SD) 2.4 (0.8) versus 4.1 (2.3) minutes in adults, P<0.01. The times to 10% spontaneous recovery of the first twitch (T1) were respectively, 28.4 (5.2) and 41.8 (6.1) minutes in children and adults, P<0.01. Spontaneous and antagonist assisted neuromuscular recovery was more rapid in children. Adequate neuromuscular recovery (train of four (TOF) ratio 80%) was achieved in children at 3 and 10 minutes after edrophonium 1.0 mg.kg -1 and 0.4 mg.kg -1, respectively. A TOF ratio of 80% was not achieved, within 10 minutes, with any of the four dose levels of edrophonium in adults. The dose of edrophonium to achieve a TOF ratio of 80% (EDTOF-80 ) after 5 and 10 minutes in children were, respectively, mean (SD) 0.85 (0.38) and 0.38 (0.19) mg.kg -1. The equivalent ED TOF-80 in adults was outside the edrophonium dose range studied.