Medical Applications

Heparin Heuristics is an application that started as a means to aid in the calculation of initial heparin doses and help adjust heparin to achieve a desired ACT during catheter ablation cases where atrial fibrillation is being treated. In these case, variable amounts of heparin are given over an average three and a half hour period. The patient characteristics and heparin doses given are extremely variable.

The application is designed to estimate the likely heparin concentration before protamine is given. This enables calculation of the dose of protamine required for reversal of heparin.

In only 13 of  430 cases  (3.02%) was there a post-Protamine ACT over 200 seconds. Of these, only 3 cases had a pre-heparin ACT of less than 200 seconds. (3/430 = 0.07%). The seven  cases with a pre-heparin ACT of greater than 200 seconds had a mean difference of -6.14 seconds, with 95% confidence intervals of  -22.69 to 10.40 seconds. This means that the overall trend is still to have a decreased ACT after protamine compared with the pre-heparin ACT in these patients.

Note: Minor bugs fixed preventing incorrect entries when MRN not entered (required field) 12 Dec 2019.

     * Statistical analysis rewritten to enable winsorized means to be used 08 March 2020

     * Version 3.4 has been modified to enable calculation of heparin clearance in order to simplify the use of a heparin infusion where tis is used (ablation version). If no heparin infusion is required, this can  be safely ignored. We are currently working on a user manual which  takes priority over other considerations.

Heparin Heuristics Application