RESUMEN
PURPOSE: The option of selecting isotonic rather than hypotonic fluids for maintenance fluid in children has been advocated by some authors. Pneumonia and CNS infections are frequent clinical settings for acute hyponatremia because of nonosmotic anti-diuretic hormone stimuli in children. We conducted the present study to identify the incidence of hyponatremia in pneumonia and CNS infection of children and to determine the importance of maintenance intravenous fluid therapy regimen and other related factors. METHODS: The study included 1,992 patients admitted to the Department of Pediatrics at Pusan National University Children's Hospital between November 2008 and August 2011, who were diagnosed with pneumonia or CNS infections and checked for serum sodium concentration. Their clinical data including laboratory findings were reviewed retrospectively. RESULTS: During the study period, 218 patients were identified to have acute hyponatremia among 1,992 patients. The overall incidence of hyponatremia was 10.9%. The incidence of hyponatremia in encephalitis (37.3%) was highest and the incidence in bacterial meningitis (27.4%), viral meningitis (20.0%), bacterial pneumonia (11.1%), mycoplasma pneumonia (9.2%), and viral pneumonia (6.8%) were in descending order. The mean age was higher in hyponatremic patients than in isonatremic patients. The incidence of hyponatremia was higher in who had 0.18% NaCl in 5% dextrose (D5 0.18% NS) than 0.45% NaCl in 5% dextrose infusion (D5 1/2NS) (9.0% vs. 2.2%). SIADH was identified in 20.5% among hospital acquired hyponatremic patients after adequate evaluation for SIADH. CONCLUSION: We recommend D5 1/2NS rather than D5 0.18% NS as the maintenance fluid given to children with pneumonia or infectious CNS diseases.