MAC of sevoflurane in humans and the New Zealand white rabbit.

The minimum alveolar concentration of sevoflurane necessary to prevent movement in 50 per cent of patients (MAC) was determined to be 2.05 per cent in 20 adult surgical patients. Because this value was higher than the only other experimentally determined human MAC value for sevoflurane (1.71 per cent), MAC was also determined in New Zealand white rabbits. Comparisons of the MAC ratios of sevoflurane to other volatile anaesthetics in both the human and the rabbit suggest that the human MAC value we obtained for sevoflurane is consistent with experimental determinations of MAC of other volatile anaesthetics in humans.