Therapy of Experimental Brain Edema in Cats

Up to now, continuous experimental monitoring of the acidotic tissue metabolism (2, 10) in brain edema has been impossible. If biochemical tissue analysis is used, the effectiveness of various forms of treatment can only be established by investigation of large series of animals. However, some signs of brain edema can be recorded continuously. The accumulation of tissue fluid and the vasoparalysis in the edematous tissue will increase the brain volume, this causing a rise of intracranial pressure (7, 13, 16). On the other hand, the disturbance of the tissue function will affect the bioelectric activity(6, 8, 11). We monitored the effects of various methods of therapy on experimental brain edema in cats by continuous recording of both ICP and EEG. As local edemas may be accompanied by pressure gradients (9, 15, 16), we measured the ventricular pressure (VP) as well as the epidural pressure (EP) over both hemispheres. For a continuous assessment of therapeutical effects on both EEG and ICP, a computer was used to evaluate the EEG activity.