[Brain edema as a cause of critical states in neurosurgical patients]

The results of the studies in 120 patients after resection of tumours located in cranial fossa (40 cases), basal-diencephalic area (45 cases), hemispheres (35 cases) have shown the role of brain edema in the onset of critical conditions after neurosurgery (with consideration of a new concept concerning the mechanisms of brain edema development). It has been demonstrated that brain edema at its early stages is a biologically expedient adaptation response to any damage and is manifested in hyperhydration of all the tissues, most marked in the affected focus. Specific (neurogenic, neurohumoral) and non-specific (biochemical, autoimmune, mechanical, etc.) factors of brain edema onset have been identified. It turned out that the location of the affected focus determines the differences in neurogenic and neurohumoral mechanisms of the edema onset. The nearer the affected focus to the stem and diencephalic structures, the more marked the effect of neurogenic and neurohumoral factors and the more distinct the tendency towards edema generalization. Brain edema may be a cause of critical conditions and lethal outcomes only when it leads to dislocation and strangulation of them brain structures, and disturbances of brain metabolism and blood flow.