PREDICTIVE FACTORS FOR HIGH MORTALITY IN HYPERNATREMIC PATIENTS

Hypernatremia (serum sodium level of >145 mEq/L) is associated with hi gh mortality, This study reports an analysis of mortality in 116 patie nts with hypernatremia from two large university-affiliate teaching ho spitals, The purpose was to identify factors predictive of high mortal ity in hypernatremic patients, Medical records were reviewed to obtain the following data: serum sodium (Na+) levels; systolic (S) and diast olic (D) blood pressure (BP) at the time of admission and throughout t he hospital course; status of cognitive function; and type of fluid ad ministered, The patients were divided into two groups: expired and sur vived, Seventy-seven of 116 patients (66%) expired, while 39 patients (34%) survived and were discharged from the hospital, The mean age and gender for patients who died (70.9 +/- 15.4 years, 90% men) were not different from those who survived (66.4 +/- 17.3 years, 87% men), For the serum Na+ levels recorded at three different times (early, peak, a nd late), mean late serum Na+ level during hospital course was signifi cantly higher in patients who died than in those who survived (151.2 /- 9.2 v 143.1 +/- 8.0 mEq/L, respectively; P<.001). Mean admission se rum Na+ level (154.9 +/- 5.5 v 155.1 +/- 7.7 mEq/L, respectively) and mean peak serum Na+ level (157.5 +/- 6.5 v 156.8 +/- 9.4 mEq/L, respec tively) were not different between the two groups, Both SEP and DBP at the time of admission (P<.05) and throughout the hospital course (P<. 001) were significantly lower in the patients who died than in those w ho survived, The cognitive abnormalities consisting of confusion, obtu ndation, and speech abnormality were significantly (P<.05) higher in t he expired patients than in those who survived, Normal (isotonic) sali ne was used significantly more frequently (P<.00001) in patients who e xpired than in those who survived, Thus, this study suggests that a pe rsistently elevated serum Na+ level (possibly caused by prolonged infu sion of normal saline) in association with protracted hypotension port ends a dismal prognosis in hospitalized hypernatremic patients. Copyri ght (C) 1997 by W.B. Saunders Company.