Minimum alveolar concentration of desflurane for tracheal extubation in deeply anaesthetized, unpremedicated children

We have studied 25 children, aged 4-9 yr, to determine the minimum alveolar concentration (MAC) of desflurane at which safe tracheal extubation can be performed in deeply anaesthetized children. The end-tidal concentration of desflurane was noted at tracheal extubation. Successful extubation was defined as one in which there was no coughing or bucking on the tracheal tube during suctioning of the pharynx, no movement or coughing within 1 min of tracheal extubation and no breath-holding or laryngospasm after extubation. Successful extubation was followed by extubation at a concentration of 0.5% less, and so on in subsequent subjects, until unsuccessful extubation occurred. After a reaction, the percentage was increased in the next patient, continuing up and down in pairs, until the required number of subjects was achieved. In 50% of children aged 4-9 yr, tracheal extubation may be accomplished without coughing or moving at an end-tidal concentration of 7.7%. The end-tidal concentration of desflurane to achieve satisfactory extubation in 95% of children was 8.5%.