Pharmacist Management of Hyperkalemia: A Focus on Improving Clinical Outcomes

Treatment updates in hyperkalemia was a practical and informative topic discussed during the 2020 virtual Directions in Pharmacy® conference. Todd Brothers, PharmD, BCCCP, BCPS, presented a comprehensive overview of hyperkalemia to optimize patient care with the use of safe and effective pharmacotherapeutic agents.

Dr Brothers began his discussion by reviewing the basic physiology of potassium (an intracellular cation) homeostasis, which is primarily preserved by the kidneys (90%). Potassium homeostasis is maintained in a narrow range, and increased concentrations can vary from being inconsequential to lifethreatening malignant arrhythmias associated with increased risk of all-cause mortality. There are multiple, typically multifactorial, etiologies for the development of hyperkalemia. Symptomatology often affects both the muscular and cardiac systems, manifesting as dyspnea, muscle weakness, ventricular arrhythmias, or asystole.

There are numerous risk factors and comorbidities associated with hyperkalemia, such as kidney disease, heart failure (HF), diabetes, hypertension, advanced age, and medications. At-risk patients with comorbidities, particularly when combined (ie, chronic kidney disease and HF), may be 2 to 5 times more likely to experience chronic hyperkalemia. Acute hyperkalemia management includes preventing immediate complications, correcting serum potassium levels, and eliminating excess potassium. Dr Brothers described the traditional oral treatment option for hyperkalemia, sodium polystyrene sulfonate (SPS), and highlighted the black box warnings associated with its use, particularly the risk of gastrointestinal injury and the need to separate administration from other medications by at least 3 hours.

Dr Brothers further discussed clinical trial data leading to the FDA approval of 2 oral treatment options for hyperkalemia, patiromer and sodium zirconium cyclosilicate (SZC). These agents exchange potassium ion with either calcium (patiromer) or hydrogen and sodium (SZC) within the gastrointestinal tract. In addition, both patiromer and SZC have substantial clinical trial data when compared with SPS that support their safety and efficacy in conjunction with better tolerability and adverse effect profiles.

Data from the DIAMOND and DIALIZE trials were reviewed during the presentation. The DIAMOND trial assessed patiromer use in improving outcomes among patients with HF with or without chronic kidney disease who were treated with guideline- directed renin-angiotensin-aldosterone inhibitors (RAASi) HF therapies. The results are expected to be made available in 2022. Dr Brothers highlighted the DIALIZE trial next, stating that this was the first randomized, placebo-controlled trial evaluating an oral potassium-binding agent in patients receiving stable hemodialysis. Results demonstrated that SZC was effective and well tolerated for pre-dialysis hyperkalemia in endstage renal disease. Of particular significance, patients receiving RAASi therapies can be maintained at optimal treatment dosing without the need for adjustment due to hyperkalemia.

Dr Brothers concluded the presentation with the pivotal role of the pharmacist in the management of hyperkalemia, regardless of the practice setting. Pharmacist consultation may include providing therapeutic recommendations, monitoring patient responses, and developing guidelines. Pharmacists also serve as educators for clinicians and patients regarding safe and appropriate medication use, with the overarching goal of maximizing clinical outcomes and minimizing the health care expenditure burden of hyperkalemia.

TODD BROTHERS, PharmD, BCCCP, BCPS, a graduate of MCPHS—Boston, is a dual board-certified clinical pharmacist, specializing in pharmacotherapy and adult critical care medicine. His pharmacy experience has spanned across community, research, and hospital-based practice. Didactically, he delivers content in the Doctor of Pharmacy curriculum in the areas of infectious disease, cardiology, renal, and pulmonary diseases. His scholarship focuses on patient safety, pharmacovigilance, health care quality improvement, and outcome measurement assessments. Dr Brothers maintains a critical care and internal medicine clinical consultation service at Roger Williams Medical Center in Providence, Rhode Island.