Comparison of the Serum Electrolyte Levels among Patients Died and Survived in the Intensive Care Unit

Background: This study aimed to evaluate the prevalence of serum sodium and potassium disorders and assess their effects on mortality rate in hospitalized patients in the ICU and also to identify prognosis and predictors of survival. Materials and Methods: A retrospective case-control study was conducted on 457 hospitalized patients in the ICU of Rasoul-e-Akram Hospital (Tehran, Iran). There were two groups: 239 patients who died in the ICU(cases) and 218 patients who were discharged from the ICU(controls). Normal serum concentrations of sodium and potassium were considered as 135-150 and 3-5.5 mEq/L, respectively. Data were analyzed using Chi square test, Independent t-test, One Way ANOVA, Correlation and Receiver Operating Characteristic (ROC) curve. Results: The mean serum sodium concentration in patients who died and discharged patients was 137.56(SD=8.56) and 137.17(SD=5.11) mEq/L, respectively. Whereas, hyponatremia was significantly more common in expired patients (39.7 % vs. 28%, P<0.001). On the other hand, the mean seru