Reducing the determination errors of the international normalized ratio by using plasma cogulation calibrators

Abstract

The objective was to use of a minimum number of ISI (International Sensitivity Index) to determine the International Normalized Ratio (INR). This specific calibration methods allowed to calculate ISI for all other thromboplastines comparative with the reference thromboplastine. Bigger values than 1 show a decrease sensitivity, as compared with the reference thromboplastine. The Prothrombin Time (PT) values are not the same in all laboratory because of differences in sensitivity of thromboplastins used. To standardize the same results in any laboratory, an INR (International Normalised Ratio) constant has been introduced. Estimation of thromboplastine sensitivity is useful in any laboratory involved in the medical control of therapy with AVK, being also helpull for the clinicians to find out a suitable curative dealing.