MANAGEMENT OF NEUROSURGICAL PATIENTS WITH HYPONATREMIA AND NATRIURESIS

THE MAIN OBJECTIVE of our study was to evolve a practical management p rotocol for neurosurgical patients with hyponatremia and natriuresis, based on their blood volume status and hematocrit. Twenty-one patients with hyponatremia and natriuresis and 3 control patients were studied . Patients with hyponatremia were categorized on the basis of their he matocrit, central venous pressure, and total blood volume. Group A con sisted of patients with hypovolemia and anemia (16 patients); Group B patients had hypovolemia but no anemia (5 patients); Group C included those with hypervolemia (0 patients). Patients in Groups A and B recei ved isotonic saline ( > 50 ml/kg/d) and oral salt (12 g/d). Additional ly, those in Group A were transfused with 500 mi of whole blood. The e nd points in the study were 72 hours after entry or two consecutive se rum sodium values of > 130 mEq/L, whichever was earlier. Hyponatremia was corrected in all the patients within 72 hours (1 patient, < 24 h; 13 patients, < 48 h; and 7 patients, < 72 h). We conclude that most ne urosurgical patients with hyponatremia and natriuresis have hypovolemi a, with or without anemia. Fluid and salt replacement and a blood tran sfusion rather than fluid restriction often results in the correction of the hyponatremia. Our findings offer indirect evidence to support t he hypothesis that in most of these patients, hyponatremia is caused b y cerebral salt wasting syndrome, rather than the syndrome of inapprop riate secretion of antidiuretic hormone.