THE INITIAL STAGE OF TESTING THE DEVELOPED APPARATUS TO DETERMINE THE INTERNATIONAL NORMALIZED RATIO

Prothrombin time (PTT) is a laboratory indicator that allows to evaluate the external pathway of blood coagulation (activity of factors I, II, V, VII and X). An INR indicator was introduced to standardize the results of the PTV test. INR = (patient’s PTT/PTT norm) ISI. The control of the INR is gaining popularity with the help of portable coagulometers. On the russian market are CoaguChek XS, qLabs Electrometer. The main problem is their high cost and high cost of operation. Russian scientists have long wondered about import substitution. However, in the literature there is no information on testing development. When developing an experimental model for measuring INR and PTV, we were guided by the results of the literary search in the scientometric databases Elibrary, Scopus, PubMed and WoS, taking into account the estimated cost of the developed model.Background. To conduct the initial stage of testing an experimental model with a comparison of the results obtained with the data of a certified laboratory.Materials and methods. We examined 70 patients (26 men and 44 women) taking «Warfarin». The material for measuring the experimental model was capillary blood. We used the qLabs® PT-INR Test Strip as a test system.Results. We obtained the Difference of the PTT of the tested model and the results of the certified laboratory ± 1–2 seconds. PTT prothrombin calibrator was 13 sec. Prothrombin ratio prothrombin calibrator was 1.0. Patient №1. PTT on the tested device 34 seconds. ISI troboplastin on test strip was 1.0. INR = (34 sec / 13 sec × 1.0)1.0 = 2.62. The result of a certified laboratory: PTT 36 sec, INA 2.86. Patient №2. PTT on the tested device 31 sec. INR = (31 sec / 13 sec × 1.0)1.0= 2.38. The results of the certified laboratory: PTT 32 sec, INR 2.48.Conclusions. According to the presented results obtained during testing of the developed portable model in patients on warfarin therapy, comparable results of PTT and INA were obtained with a certified laboratory.