Dose-response characteristics of pancuronium in neonates, infants and children.

This paper presents pharmacodynamic data for pancuronium in neonates, infants, children and adolescents during N2O-O2-fentanyl anaesthesia. Neuromuscular block (NMB) was evaluated by the adductor pollicis electromyogram. Dose-response curves of pancuronium were parallel in all age-groups. ED95 was greatest in children and least in infants (93 vs. 66 micrograms/kg, P less than 0.05). The rate of spontaneous recovery following 95% NMB was comparable in all age-groups, as was the maintenance requirement of pancuronium when related to ED-values. The hourly requirement to maintain NMB greater than 85% was 60-68% of the individual ED95 dose. When administered on this basis, pancuronium is an equally long-acting neuromuscular blocking agent in patients of all ages.

Comparison of thumb acceleration and thenar EMG in a pharmacodynamic study of alcuronium.

We compared thumb acceleration (Acc) and thenar electromyography (EMG) techniques by evaluating the neuromuscular blocking properties of alcuronium in 14 ASA physical status I patients. The dose-response curves determined by the two techniques were parallel but the EMG-curve was shifted 25% to the right (P less than 0.001). Acc reflected 8-11% greater neuromuscular block than simultaneous EMG in every patients (P less than 0.05). Concurrently, the duration of greater than 90% neuromuscular block maintained by alcuronium 280 micrograms/kg was significantly longer when measured by the Acc transducer (30 vs. 19 min, P less than 0.001). Although the TOF ratios were in good correlation (r2 = 0.82), clinically significant differences existed between the two simultaneous techniques. The results underline the importance of the method of assessment of neuromuscular transmission when evaluating the action of neuromuscular blocking drugs.