Monitoring unfractionated heparin therapy with antifactor Xa activity results in fewer monitoring tests and dosage changes than monitoring with the activated partial thromboplastin time.
OBJECTIVE
To determine how much more costly it is to monitor unfractionated heparin (UFH) therapy by antifactor Xa heparin activity (HA) than by activated partial thromboplastin time (aPTT).


METHODS
Prospective, randomized, unmasked, cohort, single-center study.


METHODS
A 625-bed, adults-only, private teaching hospital.


METHODS
Two hundred sixty-eight patients with a variety of indications for UFH therapy.


METHODS
Patients were treated with UFH based on ideal weight (75 U/kg bolus, 20 U/kg initial infusion) and monitored by either HA or aPTT, MEASUREMENTS AND MAIN RESULTS: After adjusting for gender, groups were equivalent in patient characteristics and UFH dosage. The HA group had fewer monitoring tests and dosage changes/24 hours than the aPTT group. These reductions neutralized much of the increased cost of the HA assay itself.


CONCLUSIONS
Monitoring UFH therapy over 96 hours with an HA assay costs $4.37 more than monitoring with aPTT. This modest increase may be acceptable given other advantages of the HA assay.
Rosborough
T K
TK
Medical Education Department, Abbott Northwestern Hospital, Minneapolis, Minnesota 55407, USA.
D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D000925:Anticoagulants / Q000008:administration & dosage* / Q000097:blood; D015331:Cohort Studies; D016903:Drug Monitoring / Q000191:economics* / Q000592:standards*; D065427:Factor Xa Inhibitors; D005260:Female; D006493:Heparin / Q000008:administration & dosage* / Q000097:blood; D006801:Humans; D008297:Male; D008875:Middle Aged; D010314:Partial Thromboplastin Time; D011446:Prospective Studies
D000925:Anticoagulants; D065427:Factor Xa Inhibitors; D006493:Heparin