Evaluation of a pharmacist-managed electrolyte protocol in outpatients on antiarrhythmic medications

To evaluate the effectiveness of a pharmacist-managed treatment protocol in achieving and maintaining serum potassium level ([K⁺]) in the desired range.

Antiarrhythmic Medications Clinic, The Ohio State University Wexner Medical Center, Columbus, Ohio, from 2009 to 2013.

Patients are referred for antiarrhythmic monitoring at this pharmacist-run, electrophysiologist-supervised clinic. Each visit includes medication reconciliation for drug interaction identification, patient interview for potential adverse effects or arrhythmia symptoms, patient education, and drug therapy monitoring through ordering and review of objective testing.

In 2009, a novel, pharmacist-managed electrolyte protocol was established for less than ideal [K⁺] found during antiarrhythmic monitoring. The protocol was intended to standardize and improve practice, versus pre-protocol management through separate electrophysiology offices. The protocol was designed to maintain [K⁺] of 4.0-5.0 mmol/L, and it used dietary advice and magnesium and potassium supplementation to normalize [K⁺].

The performance of the pharmacist-managed electrolyte protocol was evaluated in consecutive patients seen between June 2009 and July 2013 with [K⁺] less than 4.0 mmol/L. [K⁺] during initial visit and laboratory tests were scheduled at weekly intervals after intervention until corrected. Maintenance of [K⁺] was assessed during the next visit to the clinic. Patients whose management involved pre-protocol between October 2008 and May 2009 at the clinic served as controls.

One-hundred ninety-one encounters were evaluated from the post-protocol (treatment) group and 41 encounters from the pre-protocol (control) group. Desired [K⁺] was reached in 161 (84%) post-protocol patient encounters, compared with 21 (49%) in the control group (P < 0.01). Median time to target was 14 days (range, 3-203 days) in the treatment group and 146 days (range, 7-285 days) in the control group (P < 0.01). Of 125 encounters that received follow-up in the treatment group, 75% remained at desired [K⁺].

A pharmacist-managed electrolyte protocol, implemented as part of a comprehensive antiarrhythmic monitoring service, effectively achieves and maintains desired [K⁺].