Point-of-care versus laboratory monitoring of patients receiving different anticoagulant therapies.
OBJECTIVE
To compare point-of-care and standard hospital laboratory assays for monitoring patients receiving single or combination anticoagulant regimens.


METHODS
Prospective analysis.


METHODS
Nursing units and clinics at a large, community hospital.


METHODS
One hundred fifty patients receiving anticoagulants for cardiac, vascular, orthopedic, or cancer indications. Thirty patients were enrolled into each treatment group: warfarin, enoxaparin, heparin, warfarin plus enoxaparin, and warfarin plus heparin.


METHODS
Capillary and venous blood samples were collected once in each patient for simultaneous measurement of international normalized ratio (INR) and activated partial thromboplastin time (aPTT) by both assays.


RESULTS
Mean differences in paired INR and paired aPTT by point-of-care and standard assays were small, but 95% confidence intervals were wide. The INR differences were greater for the warfarin plus heparin group than for the warfarin group or warfarin plus enoxaparin group; clinical decision agreement was 47% for warfarin plus heparin, 73% for warfarin, and 93% for warfarin plus enoxaparin. The aPTT difference was greater for the warfarin plus heparin than for the heparin group; however, clinical decision agreement, 67% and 70%, respectively, was similar.


CONCLUSIONS
Point-of-care methods showed limited agreement with standard hospital laboratory assays of coagulation for all treatment groups. For INR values, significantly greater disagreement was noted between the assay methods for the warfarin plus heparin group compared with the warfarin group, but the agreement was similar for the warfarin and warfarin plus enoxaparin groups. Our data indicate that the point-of-care assays should not be considered interchangeable with standard laboratory assays.
Reiss
Robert A
RA
Department of Pharmacy Services, ViaHealth-Rochester General Hospital, New York, USA.
Haas
Curtis E
CE
Griffis
Deborah L
DL
Porter
Bernadette
B
Tara
Mary Ann
MA
D000368:Aged; D000925:Anticoagulants / Q000627:therapeutic use*; D016903:Drug Monitoring / Q000379:methods*; D006764:Hospitals, Community / Q000458:organization & administration; D006801:Humans; D019934:International Normalized Ratio; D007755:Laboratories, Hospital; D010314:Partial Thromboplastin Time; D019095:Point-of-Care Systems; D011446:Prospective Studies
D000925:Anticoagulants