Comparative study of a portable monitor for prothrombin time determination, Coaguchek (R), with three systems for control of oral anticoagulant treatment
M. Vacas et al., Comparative study of a portable monitor for prothrombin time determination, Coaguchek (R), with three systems for control of oral anticoagulant treatment, HAEMOSTASIS, 28(6), 1998, pp. 321-328
Self-testing of oral anticoagulation is a new possibility related to the de
velopment of portable capillary whole blood prothrombin time monitors. The
aim of this study was to evaluate one of this monitors, Coaguchek(R), with
respect to its comparability with our routine prothrombin time determinatio
n system, as well as with the reference manual technique and two thrombopla
stins of high sensitivity, Manchester Reagent and one manufactured in our c
enter, Thromboplastin Bilbao, in a group of patients on oral anticoagulant
treatment. Although a correlation of r = 0.9271 was found between internati
onal normalized ratio (INR) values of Coaguchek and our routine method, Neo
plastine/STA analyzer, the difference of the INR scatter increased with the
magnitude of measurement, being lowest for INR between the portable monito
r and Manchester Reagent and Thromboplastin Bilbao, with a similar coeffici
ent of correlation, r = 0.8948 and r = 0.8905, respectively. A test was per
formed showing a 65.6% agreement with the INR values of the STA analyzer, 6
6.4% with Manchester Reagent and 73.4% with Thromboplastin Bilbao. On the b
asis of this correspondence with laboratory prothrombin time results Coaguc
hek may be considered as a possible option for monitoring anticoagulated pa
tients even though patients should be given instructions and advice as rega
rds the management and interpretation of the results.