[Effects of the intravenous infusion of althesin on intracranial pressure and related functions].

30-60 min after the i.m. administration of 0.5 mg atropine sulphate, 9 adult conscious neurosurgical patients on spontaneous ventilation were given a total of 12 i.v. infusions of Althesin at a rate of 0,25-0,60 ml/kg/h able to induce stable clinical and EEG levels of anaesthesia. PICm, PAm and PVCm respectively decreased in all, in ten and in six administrations. The PAm decreased below 60 mmHg in only one case, in another there was no change and in another still it increased in a stable manner. In all cases PICm, PAm and PVCm decreased by a mean of 3.88 +/- 1.22 (P < 0,05), 20,76 +/- 17,44 (P < 0,05) and 0,90 +/- 1,50 mmHg. The paCO2 generally increased and, in only one case, did it induce an intracranial hypertensive reaction; the paO2 was frequently reduced. The interruption in the infusion was followed by the regression of all effects. This appened for the PICm and PAm without dangerous rebound effects. The clinical use of Althesin in neurosurgical patients is discussed with regards to problems of anaesthesia and intensive care.