[The classification of hypno-analgesics (author's transl)]

Experience collected by routine E.E.G. studies of narcosis, in volunteers in good health, serves as a basis for a classification of anaesthetic agents. In order to obtain this, we established a correlation between the electroencephalographic effects on the one hand and psychological, motor, sensory and vegetative changes on the other hand. Arguments emerged in favour of the existence of different points of impact for different substances or groups of substances. A distinction was made between holoencephalic hypno-analgesics (affecting the activity of practically all the neurone systems of the brain) and the neuroleptics, tranquilisers and analgesics which have only a limited effect on the telencephalon, neocortex and archicortex, the electroencephalographic actions of which also differ from the classical stages of narcosis. Using this classification based upon the principal points of action of these agents and their possible effects on other systems it is possible to explain the existence of adequate and inadequate associations of medications during so-called balanced anaesthesias.