Comparison of a point-of-care and standard laboratory analyzers to determine prothrombin and activated partial thromboplastin times in asian elephants (elephas maximus)

Abstract

Coagulation testing may aid veterinarians in the early identification and management of disease. Clinical application of these diagnostics may be hampered by delays associated with transporting samples to central veterinary laboratories, especially when working in remote locations. The objective of this study was to compare prothrombin times (PT) and activated partial thromboplastin times (aPTT) in Asian elephants (Elephas maximus) determined by a point-of-care (POC) analyzer to those determined by a standard laboratory unit. Captive elephants (n = 64) of both sexes and three age classes (juvenile, adult, and geriatric) in Kanchanaburi Province, Thailand, underwent venipuncture during routine clinical assessment. PT and aPTT were determined immediately using a handheld POC device (qLabs Coag Panel 2, Micropoint Biotechnologies Inc., Shekou, Shenzen, Guandong 518067, China). Citrated plasma was used to determine PT and aPTT at the veterinary diagnostic laboratory at Chulalongkorn University, Bangkok, on a standard analyzer (Sysmex Automated Blood Coagulation Analyzer CA-500 Series, Sysmex Corporation, Kobe, Hyogo 651-0073 Japan) 24-31 h following venipuncture. Results were compared by Bland-Altman plots and Passing-Bablock regression analyses. There were significant systematic, constant and proportional biases for PT and aPTT for both analyzers. The POC analyzer significantly overestimated PT and aPTT values by a mean of 11.9 s (95% confidence interval [CI], 11.4-12.4 s) and 117.6 s (95% CI, 115.0-120.1 s), respectively. The results of this study show a large discrepancy between PT and aPTT values between a POC coagulometer and standard analyzer, confirming the need for analyzer-specific reference intervals for their use in clinical care.