Metocurine requirements and plasma concentrations in burned paediatric patients.

A cumulative dose-response study for metocurine was performed on 11 burned and 11 non-burned children during thiopentone, nitrous oxide in oxygen and narcotic anaesthesia. Burned children required a significantly (P less than 0.001) greater dose (three-fold) of metocurine to achieve a given degree of neuromuscular blockade compared with non-burned children. For the same degree of twitch depression, burned children required twice the plasma concentration of metocurine. Despite the larger dose, the recovery time for the twitch was not significantly different in the two groups. It is speculated that there may be fundamental changes at the neuromuscular junction of burned children to account for their resistance to the effect of non-depolarizing neuromuscular blockers.