Papaveretum for anaesthesia and its comparison with morphine. Anaesthetic time/dose curves VIII.

Intravenous papaveretum was used for the induction and supplementation of nitrous oxide-relaxant anaesthesia in 32 subjects undergoing major surgical operations. An anaesthetic time/dose curve was constructed from the size and timing of successive narcotic increments received by each patient and from these the loading and maintenance requirements of the group were determined. Compared with a similar series in which plain morphine was employed in the same fashion, the morphine content of papaveretum accounted for only 82 per cent of the observed anaesthetic activity. Since the remaining 18 per cent was provided by more readily inactivated alkaloids, papaveretum's therapeutic half-life was only 58 per cent (3.61 hr) of morphine (6.18 hr). All the statements outlined above proved to be statistically significant to various degrees. The advantages of a shorter acting morphine-like compound in anaesthesia are discussed.