This study of spontaneous night sleep in porto-caval encephalopathy (PCE) concerns 18 polygraphic recordings from 15 cirrhotics in different stages of encephalopathy. The following were studied in each subject: the EEG and behavioural aspects of sleep, their general characteristics (total duration, speed of going to sleep, variability and duration of the various sleep stages), the vegetative changes and the cyclic organization of sleep during the night. When the classic stages of physiological sleep were no longer recognizable the results were interpreted according to criteria which are discussed. Correlations were established between the clinical and EEG severity and the arterial ammonia level on the one hand and the EEG features, the duration of sleep and its organization on the other. This analysis showed that sleep in PCE differs profoundly from that of normal subjects. The conservation or not of the physiological character of night sleep is a function of the state of vigilance and the diurnal disturbances of the EEG. With worsening of the encephalopathy successive pathological variations of physiological sleep appear, followed by a true pathological sleep corresponding to progressive breaking down of the sleep function. But whatever their kind and intensity the disturbances of sleep remain reversible and appear to be related to ammonia metabolism.

Cette étude du sommeil nocturne spontané de l'encéphalopathie porto-cave (EPC) porte sur 18 enregistrements polygraphiques de 15 cirrhotiques présentant divers stades de cette encéphalopathie.