Evaluating standardized weight based heparin nomogram vs. patient specific dosing to achieve and maintain targeted activated partial thromboplastin time (aPTT) at a quaternary care teaching hospital

Purpose:  At North Shore University Hospital (NSUH),  there are two order forms for intravenous (IV) heparin use; Standardized weight based dosing nomograms with preselected aPTT targets, doses are initiated by prescribers based on indication and  may be titrated by nurses. Patient specific order form is also an option, allowing the prescriber to select aPTT targets and initial dosing; dosing titrations are made at the discretion of the physician. Primary objective was to compare these two methods of ordering heparin infusion to see which was able to achieve  targeted activated partial thromboplastin time (aPTT) faster and maintain within therapeutic range longer. Secondary objectives include number of sub therapeutic and supra therapeutic aPTT levels

Methods:  This was a retrospective chart review. Study population included, patients received IV continuous infusion of heparin at NSUH on or after June 1^st 2011 based on either the weight based nomogram or patient specific dosing form. The first 54 patients that meet the eligibility criteria were selected. For both groups, appropriateness of aPTT monitoring, time to first therapeutic aPTT, as well as the number of sub and supra aPTT levels in each group, and time within target aPTT range was evaluated.

Results: Time to first therapeutic aPTT was found to be not statistically significant between the two groups (p<0.0502). Time within therapeutic range was found to have statistical significance favoring the nomogram driven group (p<0.0021). Sub and supra therapeutic aPTT levels between groups were found to be not statistically significant (p<0.0519).

Conclusion: Patient care can be optimized by efficiently using the nomogram driven heparin dosing to maintain therapeutic aPTT levels for longer. Standardization of dosing for this high risk medication may also be explored