Evaluation of an Intravenous Potassium Dosing Algorithm for Hypokalemic Critically Ill Patients

Purpose: The intent of this study was to evaluate the safety and efficacy of an intravenous (IV) potassium (K) dosing algorithm for hypokalemic critically ill trauma patients. Methods: Adult patients, admitted to the trauma intensive care unit from June 2010 to October 2012 and who received IV K therapy according to a standardized dosing algorithm, were retrospectively evaluated. Patients who received IV K during resuscitation or following initiation of nutrition therapy, IV fluids containing >20 mEq/L of potassium, or medications known to alter K homeostasis or those with an arterial pH change >0.1, diarrhea, hypomagnesemia, renal impairment, or morbid obesity were excluded. Results: In total, 715 patients were reviewed to obtain 100 evaluable patients. Serum K for patients with mild depletion (serum K, 3.5–3.9 mEq/L, n = 74) remained unchanged at 0.0 ± 0.3 mEq/L (P = ns) following 46 ± 8 mEq. Serum K increased by 0.4 ± 0.3 mEq/L (P = .001) following 78 ± 18 mEq during moderate depletion (serum K, 3–3.4 mEq/L). None of the patients experienced hyperkalemia (serum K, >5.2 mEq/L) postinfusion. The presence of traumatic brain injury (TBI) blunted the response to IV K for mild K depletion as only 26% had an increase in serum K compared with 55% of patients without TBI (P = .025). Conclusions: The Nutrition Support Service–guided IV K dosing algorithm was safe for patients with mild and moderate hypokalemia and efficacious for those with moderate hypokalemia. Further study in patients with severe hypokalemia (serum K,