Goals and opportunities of bedside hemostasis screening tests
Authors: Roitman E. V. , Shabalina A. A. , Tanashyan M. M. , Dmitrieva N. Yu. 
Published: January 2025

Introduction. Hemostasis screening tests – activated partial thromboplastin time (APTT), prothrombin time (PT) with results expressed as international normalized ratio (INR), thrombin time (TT), fibrinogen concentration (Fg) were initially developed to reveal the causes of bleeding and to assess hemorrhagic risk. Citrate plasma is traditional object followed by blood cells effects on hemocoagulation are lost. A more realistic picture should be provided by hemostasis screening with whole (citrated) blood that allows point-of-care (POC) testing due to exclusion a preanalytical procedures. However, hemostasis POC-screening with whole blood still raises a number of questions.

The objective was to assess a consistency between POC hemostasis testing by whole blood and the same tests by reference methods in the laboratory, and to study how high/low hematocrit and high/low platelet counts influence on the POC hemostasis assays.

Materials and methods. Blood samples were collected as a part of routine check-up for neurological patients (n = 80) at Research Center of Neurology. Patients did not have diseases or complications predisposing to plasma hypocoagulation and did not take anticoagulants as well. Hemostasis tests (n = 100 for each of APTT, PT, TT, Fg) were performed from whole citrate blood using cartridge technology with portable POC hemostasis analyzer OCG-102 (Guangzhou Wondfo Biotech Co., Ltd, China). The results of the tests of the same name obtained from citrate plasma using a standard technique on an automatic coagulometer ACL Elite Pro (Instrumentation Laboratory, USA) was accepted for comparison as a reference mode. The software package «IBM SPSS Statistics», ver. 25 (IBM, USA) was used for statistical analysis. The data is presented as Me [Q1; Q3]. The comparative analysis was performed with nonparametric method using Wilcoxon criterion. Linear regression analysis and nonparametric Spearman correlation were used to assess the influence of platelet count and hematocrit values (categorical variables). Confidential level as p < 0.05 was assumed for each statistics.

Results. About 3–4% of POC assays have failed but that has happened at the initial stage of working with the POC-device. All POC-tests fell within the reference values. Statistically unreliable shift was revealed for repeated POC-assays (after 30 minutes) except INR explaining by cumulated error. Excepting Fg test, results of other whole blood tests have been longer of 7–9% than in plasma (p < 0.05) but their values were not out the reference ranges. Data analysis showed that moderately reduced or moderately elevated values of hematocrit (35–40% and 45–55%, respectively) and platelet count (140–180 thousand/μl and 380–450 thousand/μl, respectively) didn’t affect significantly POC tests.

Conclusion. The results of POC-screening from whole citrate blood do not differ either diagnostically or clinically from the results obtained by the traditional method from citrate plasma. Moderately reduced or moderately elevated values of hematocrit and platelet count, which are the most common in practice, do not significantly affect the results of whole citrate blood POC tests. Thus, the implementation of POC-screening of hemostasis from whole citrate blood is obviously intended for use in intensive care and intensive care units, reception and surgical departments and perinatal centers with prospects for expanding use in anticoagulant therapy rooms, mobile medical diagnostic complexes and small medical and preventive institutions.