[The influence on water-electrolyte balance through osmotherapy for decreasing intracranial pressure]

On the basis of a group of neurosurgical patients showing a differing composition, various procedures of the dehydrating therapy in the pre- and postoperative phases for decreasing the increased intracranial pressure were studied. In addition to the continuous recording of the intracranial pressure, the electrolyte and water balance was measured by recording the plasma, urinary, and cerebrospinal-fluid electrolytes and their osmolarities and the urinary output was determined. Besides, specific measurements of the haematocrit, of the central venous pressure and the arterial mean pressure brought pathophysiological findings on the dehydration. The comparison of conventional substances such as mannite and sorbite of different concentrations per time showed various disturbances of the electrolyte and water balance; therapeutic guiding rules could be elaborated under consideration of these experiences. On the basis of the intracranial pressure/volume relationship, the effectiveness of the dehydration should not only be assessed by the reduction of the intracranial pressure since the extent of the alteration of the electrolyte and water balance and the haemodynamically active changes are quite different. Finally, disease pictures should be taken into consideration in which the basic morphological and functional conditions have been lost and the limits of the therapeutic procedure are exceeded.