[Pathologo-anatomical characteristics of hyperosmolar and other comatous conditions].

Fifty-four cases of death from hyperosmolar comas were examined pathoanatomically together with the postmortem biochemical analysis of the CSF and blood. Brain of animals with disturbances of the blood and CSF osmolarity was studied electron cytochemically and autoradiographically. It was discovered that the hyperosmolar comas are manifested by excosis and brain collapse. The brain is reduced in volume due to deep cell-extracell dehydration and alteration of the hematoencephalic barrier with the irreversible depression of the neuronal and glial metabolism. In 7 patients dying with the purulent-necrotic changes of vessels resulting from the hyperosmolar effect of verografin used for the carotid angiography, numerous perivascular hemorrhages developed in the brain. Dysequilibrium syndrome in hemodialysis is manifested by an acute brain swelling or by a formation at a later period of symmetrical ischemic-hemorrhagic necrosis in the thalamus and occipital lobes of the large hemispheres.