Pharmacy-managed, weight-based heparin protocol

Abstract

A revised protocol for heparin therapy, in which dosing was based on the patient's weight and the pharmacy staff assumed responsibility for management of the treatment protocol, was evaluated. A fixed-dose protocol for heparin therapy, in which an initial loading dose and infusion rate were specified by physicians and partial thromboplastin times (PTTs) were determined every 12 hours, was revised to determine dosing based on patient weight and diagnosis and to include more levels of dose adjustment and additional laboratory tests. Data on demographic characteristics of patients, heparin therapy, laboratory monitoring, conversion to warfarin therapy, and protocol management were collected for the patients receiving heparin under the revised protocol. Results were compared with those obtained for the old, fixed-dose protocol, which was managed by nursing staff. The revised protocol showed improvements in heparin therapy according to commonly accepted treatment criteria, including dosages, time to achieve a PTT associated with therapeutic anticoagulation, and the time a patient was in the target PTT range. The new protocol was also significantly more effective in avoiding low as well as high PTT ratios. The laboratory monitoring mandated by the revised protocol enhanced the monitoring of heparin therapy, and pharmacy management improved the accuracy and documentation of heparin therapy. Under the revised protocol, anticoagulation goals were attained more rapidly, and dosing changes were more likely to be correct and appropriately documented.