System Dose Conversion Protocol Evaluation and Formulary Exclusion of U-500 Insulin

Service or Program:

To promote safe and cost-effective blood glucose management, HealthEast Hospitals removed U-500 insulin from formulary and implemented a conversion protocol for hospitalized patients.

Justification/Documentation:

The Institute for Safe Medication Practices (ISMP) recognizes an increase in medication errors related to dose conversions of home U-500 insulin to inpatient regimens and has called upon health systems to implement practices that avoid inappropriate dosing.  Inaccurately reported insulin doses is a common error leading to a potential 5-fold overdose when using U-500 insulin.  Standards of practice and protocols are necessary in managing this high risk medication.

Transferability:

Decentralized clinical staff pharmacists are uniquely positioned to provide alternative conversion recommendations to prescribers for all concentrated insulins. In collaboration with the diabetes educators, a protocol was approved by HealthEast’s P&T Committee and Medication Safety Committee. All U-500 orders are converted to a basal/prandial insulin regimen in a 50:50 ratio utilizing insulin glargine and insulin aspart along with a custom resistant correction bolus. Prescriber acceptance of the recommendation is required before initiation of the conversion regimen.

Impact:

An evaluation of this implemented protocol was completed from January 1^st, 2015 to December 23^rd, 2015.  Ten hospitalized patients with orders to resume home U-500 insulin were reviewed.  Eight of ten (80%) patients were initiated on a pharmacist recommended insulin glargine/insulin aspart regimen per protocol. Of those initiated on the protocol, no hypoglycemic events [blood glucose (BG)<70mg/dl] were documented and four hyperglycemic events (BG>200mg/dl) were documented. No incorrect U-500 insulin dose administrations or safety events have been reported following protocol initiation. Concentrated insulins pose new challenges for pharmacists and implementing U-500 formulary exclusion and conversion protocols further promote safe and cost-effective blood glucose management.