Evaluation of a Tiered Potassium Replacement Protocol in Post-Operative Patients Admitted to a Pediatric Cardiac Intensive Care Unit.

Objective: To evaluate the efficacy and safety of our institution's tiered intravenous potassium replacement protocol in pediatric patients admitted post-operatively to the pediatric cardiac intensive care unit. To our knowledge, this is the only study evaluating the specific parameters of a potassium replacement protocol similar to ours.

Methods: This retrospective, single-center, observational study evaluated children up to 18 years of age admitted post-operatively to the pediatric cardiac intensive care unit between September 1, 2022 and January 31, 2023 who received 1 or more doses of intravenous potassium per our institutional replacement protocol for a hypokalemic episode (serum potassium concentration less than or equal to 3.7 mEq/L). All patients, hypokalemia episodes, replacement doses, and subsequent serum potassium concentrations were evaluated until post-operative day 5.

Results: There were 23 patients included with a total of 95 episodes of hypokalemia. For both tiers of the replacement protocol, a median of 1 dose was required to resolve hypokalemia. Two incidences of hyperkalemia (serum potassium greater than or equal to 5.5 mEq/L), 2.1% of total, were proven or suspected to be true, both classified as moderate hyperkalemia. All episodes of hyperkalemia were not associated with ECG abnormalities and did not require treatment.

Conclusions: Despite utilizing higher serum potassium concentration thresholds for replacement as well as higher maximum dosing than published literature, our protocol was effective at resolving hypokalemia, as defined by our protocol, without leading to significant hyperkalemia.