Decreasing IV magnesium infusion time to improve delivery of patient care.

Abstract

Introduction: Hypomagnesemia is a common issue in patients with cancer due to magnesium wasting drugs like calcineurin inhibitors, chemotherapy sides effects such as diarrhea, and poor oral intake. Historically, magnesium has been given over prolonged infusions due to concern for rapid elimination of magnesium when large doses are administered. At UW Health, magnesium was given at a rate of 1g/60 min. A prolonged infusion rate often creates logistical issues including limited IV access, incompatibility concerns and increased chair time. The purpose of this project is to increase the infusion rate of IV magnesium without compromising therapeutic repletion, benefit, and safety.

Methods: The magnesium infusion rate was increased to the following rates: 4g/60 min, 2g/30 min, 1g/15 min. The primary outcome is the grams of IV magnesium replaced per outpatient visit between the pre-intervention (prolonged) and post-intervention (rapid) groups. Secondary outcomes include assessment of differences in chair time between groups and total incidence of critical magnesium lab values.

Results: There was no statistically significant difference in magnesium requirements per outpatient visit between a prolonged and rapid magnesium infusion rate (2.18g vs 2.15g; p = 0.49). Additionally, there was no difference in number of outpatient visits (3 vs 3; p = 1). The average chair time was decreased by 110 min per outpatient encounter between the prolonged and rapid magnesium infusion rate, which was determined to be clinically and statistically significant.

Conclusion: This study suggests that there is no difference in magnesium requirements between a rapid or prolonged magnesium infusion in both solid and liquid tumor patients.