[Disturbance in fluid and electrolytes metabolism with central origin with special reference to sodium (author's...

Clinical aspects with disturbances in fluid and electrolytes metabolism in brain diseases were discussed reviewing 41 cases experienced in our department. These 41 cases were found in 377 patients with diseases of the central nervous system in our hospital during recent 14 months. Hyponatremia was found in 19 cases and aneurysms of A-C, A1 and A2 had the majority of the cases. The cerebral angiography suggested an unstable blood supply to the anterior portion of the hypothalamus, for instance, showing remarkable shift, spasm or obstruction A-C, A1 or A2. The duration of hyponatremia was transient and mostly less than 2 weeks after the last attack of subarachnoid hemorrhage. On the contrary, hypernatremia was seen in 9 cases and 6 of them were found in cases of tumors in the pineal region and A-C, A1 and A2 were intact angiographically. The hypernatremia was continuous and did not response to V-P shunt or any kinds of infusion therapy. The hypernatremia due to cerebral disease is thought to be a result of destruction of the supraoptic and paraventricular nuclei or adjacent area in the anterior potion of the hypothalamus in most of presumed these cases. It might be that the decreased blood supply to the anterior position of the hypothalamus offers an information not of hypoosmolarity but of hypovolemic state, and this information increases the secretion of ADH. This mechanism of hyponatremia could play an important role in S.I.A.D.H.