Evaluation of a point-of-care coagulation analyzer for measurement of prothrombin time, activated partial thromboplastin time, and activated clotting time in dogs

Abstract

Objective - To evaluate a point-of-care coagulation analyzer (PCCA) in dogs with coagulopathies and healthy dogs. Animals - 27 healthy and 32 diseased dogs with and without evidence of bleeding. Procedure - Prothrombin time (PT), activated partial thromboplastin time (aPTT), and activated clotting time (ACT) were determined, using a PCCA and standard methods. Results - Using the PCCA, mean (± SD) PT of citrated whole blood (CWB) from healthy dogs was 14.5 ± 1.2 seconds, whereas PT of nonanticoagulated whole blood (NAWB) was 10.4 ± 0.5 seconds. Activated partial thromboplastin time using CWB was 86.4 ± 6.9 seconds, whereas aPTT was 71.2 ± 6.7 seconds using NAWB. Reference ranges for PT and aPTT using CWB were 12.2 to 16.8 seconds and 72.5 to 100.3 seconds, respectively. Activated clotting time in NAWB was 71 ± 11.8 seconds. Agreement with standard PT and aPTT methods using citrated plasma was good (overall agreement was 93% for PT and 87.5% for aPTT in CWB). Comparing CWB by the PCCA and conventional coagulation methods using citrated plasma, sensitivity and specificity were 85.7 and 95.5% for PT and 100 and 82.9% for aPTT, respectively. Overall agreement between the PCCA using NAWB and the clinical laboratory was 73% for PT and 88% for aPTT. Using NAWB for the PCCA and citrated plasma for conventional methods, sensitivity and specificity was 85.7 and 68.4% for PT and 86.7 and 88.9% for aPTT, respectively. Conclusions and Clinical Relevance - The PCCA detected intrinsic, extrinsic, and common pathway abnormalities in a similar fashion to clinical laboratory tests.