Response to Intravenous Potassium Chloride Supplementation in Pediatric Cardiac Intensive Care Patients

Potassium chloride (KCl) supplementation is common among critically ill children. Intravenous (IV) KCl supplementation for pediatric patients is poorly characterized. This study aimed to examine the efficacy and safety of IV KCL and to determine factors affecting patient responses to IV KCL in the pediatric cardiac intensive care unit (CICU). A retrospective review of 211 children (794 KCl doses) undergoing cardiac surgery or a hospital stay for heart failure in the CICU of a tertiary care teaching and referral children’s hospital in 2011 was performed. Demographic data, weight, height, creatinine, and concomitant medications during each KCl dose were recorded and analyzed. Body surface area (BSA), creatinine clearance, and change in [K⁺] were calculated. The median age of the children was 4 months (range, 10 days–18 years). In this study, 151 KCl doses were administered to neonates (19 %), 307 doses (39 %) to females, and 510 doses (64 %) to patients with a BSA smaller than 0.33 m² (a group with relative renal insufficiency). The mean KCl dose was 0.97 ± 0.006 mEq/kg. No adverse events were associated with IV KCl administration. Blood/plasma [K⁺] increased 0.8 ± 0.02 mEq/L. The responses to KCl did not differ significantly between males and females, between neonates and children, or between patients with a BSA smaller than 0.33 m² and those with a BSA of 0.33 m² or larger. The responses to IV KCl were attenuated by concomitant furosemide (p = 0.01), amphotericin B (p < 0.01), and KCl in parenteral nutrition (p < 0.01). The responses were augmented by concomitant enalapril (p = 0.03), ethacrynic acid (p < 0.001), and hemodialysis (p < 0.01). Intravenous KCl can be administered safely for CICU patients. Responses to KCl are altered when it is given with certain medications. Intravenous KCl should be used cautiously in children receiving angiotensin-converting enzyme inhibitors. Future studies are needed for further characterization of factors affecting responses to IV KCl in children.