A simple method for rapid and precise estimation of the protamine dose required for clinical heparin reversal.

A simple, colorimetric protamine titration method was developed for rapid and precise estimation of the protamine dose required for clinical heparin reversal. The method employs azure A dye as the titration indicator, and has replaced the time consuming clotting assay in the conventional protamine titration method with a rapid colorimetric assay. It offers the same accuracy in estimating the protamine dose as that of the conventional titration method, but allows the processing time to be shortened to within 5 min. In a similar manner, the colorimetric assay can also be employed with a heparin titration procedure to quickly assess the heparin dose required for protamine reversal. This would allow physicians to exercise a quick and accurate heparin back-titration to patients who are overdosed with protamine.