Hospital-acquired Hyponatremia in Pediatric Intensive Care Unit

OBJECTIVE The objective of the study was to evaluate the etiology of hospital-acquired hyponatremia (HAH) and its effects on morbidity and mortality in the Pediatric Intensive Care Unit (PICU) patients. DESIGN This study design was a prospective observational case-control study. SETTING this study was conducted at tertiary care PICU. MATERIALS AND METHODS All consecutive cases admitted with at least one measured serum sodium (PNa) value were evaluated. Those with normal admission PNa were followed till they develop hyponatremia (PNa < 35 mEq/L) 7 days or PICU discharge whichever was earlier. RESULTS During the study period, 123 (19.6%) cases developed HAH and 126 patients remained isonatremic (control group). The admission PNa 138.8 ± 3.03 mEq/L decreased to 132 ± 2.58 mEq/L (drop of 6.68 ± 3.39 mEq/L, P < 0.001) in HAH cases. The use of antidiuretic hormone (ADH)-stimulating drugs (odds ratio [OR]: 2.83, P = 0.01), postsurgical status (OR: 2.95, P = 0.006), and fluid intake ml/kg (OR: 1.0, P = 0.001) were found to be significant risk factors in HAH group on multivariate analysis. HAH cases had prolonged PICU stay (P = 0.000) and mechanical ventilation (P = 0.01), but no difference in the mortality when compared to controls. CONCLUSIONS HAH is associated with increased fluid intake, presence of ADH-stimulating drugs or conditions, and postsurgical status and has an adverse effect on the outcome of PICU patients.