Clinical evaluation of a microsample coagulation analyzer, and comparison with existing techniques

✍ Scribed by Carter, Andrew J. ;Hicks, Karen ;Heldman, Alan W. ;Resar, Jon R. ;Laird, John R. ;Coombs, Vicki J. ;Brinker, Jeffrey A. ;Blumenthal, Roger S.

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 536 KB
• Volume: 39
• Category: Article
• ISSN: 0098-6569
• DOI: 10.1002/(sici)1097-0304(199609)39:1<97::aid-ccd22>3.0.co;2-k

✦ Synopsis

A new microsample coagulation analyzer (Hemochrona Jr.) has recently been developed which performs a modified activated clotting time (ACT+) and an aPlT by using different reagents. The Hemochron" Jr. measures the clotting time of a Cmicroliter whole-biood sample by an optical detector and extrapolates the results to the activated clotting time (ACT+) or the plasmaactivated partial thromboplastin time by using a validated regression analysis. We compared 124 simultaneous ACT+ and Hemochron@ ACTs, and 53 paired Hemochron@ Jr. aPTTs and hospital laboratory aPTTs, in 44 patients during coronary intervention. The Hemochron" Jr. aPlT closely correlated with the lab aPTT (r = .79, P < .0001), and the test results were available much more rapidly than the lab aPTT (3.5 f 1.1 vs. 56.3 f 25.5 mln, P=0.0029). A comparison of duplicate ACT+ measurements did not identify a significant difference in the means (292 f 115 sec vs. 293 f 112 sec, P=O.72). The ACT+ closely correlated with the Hemochrone ACTs (r = .85, P < .0001). At baseline, the mean ACT+ (175 f 43 sec) exceeded the Hemochrona ACT (144 f 36 sec) by 22% (P < .001). After heparin administration, the mean ACT+ (378 f 74 sec) exceeded the Hemochron" ACT (332 f 65) by 12% (P < .001). The Hemochron@ Jr. provides a fast and reproducible methodology for measuring ACT and aPTT, using a small blood volume. Further studies are required to determine the optimal anticoagulation range when using the Hemochron@ Jr. during or after interventlonal procedures.