Efficacy of computer-aided dosing of warfarin among patients in a rehabilitation hospital.
OBJECTIVE
To determine whether computer-aided dosing of warfarin is superior to physician dosing to maintain a patient in a rehabilitation hospital within a target international normalized ratio goal.


METHODS
Randomized, double-blinded, clinical trial in an inpatient rehabilitation hospital. A total of 30 consecutive patients admitted receiving warfarin were randomized to either clinician dosing or computer-aided warfarin dosing for the duration of their hospitalization. The main outcome measures included the percentage of days in a therapeutic anticoagulation range and the number of blood draws. Exclusion criteria included short length of stay (n=110, 39%) and a physician declared international normalized ratio target range of <2.0 (n=67, 23%). A total of 73 patients were excluded because of heme-positive stools at admission, recent gastrointestinal bleed, early discharge or consent refusal. Dawn AC software was used to determine warfarin dosage and frequency of blood draws to maintain a target international normalized ratio of 2.0-3.0 for the computer-dosed group (n=14). Several physicians recommended warfarin dosages for the second group (n=16). Two were dropped from the computer model secondary to lost data files for these two patients.


RESULTS
Computer-aided dosing of warfarin resulted in 61.7% of days within the therapeutic range (international normalized ratio, 2-3), whereas clinician dosing resulted in only 44.1%. There were no significant differences in the number of blood draws or demographic variables between the two groups.


CONCLUSIONS
Computers were significantly better at maintaining patients within a therapeutic international normalized ratio range than physicians. There were no significant differences in the number of recommended blood draws.
Mitra
Raj
R
Department of Physical Medicine and Rehabilitation, Harvard Medical School, Spaulding Rehabilitation Hospital, Boston, Massachusetts 02114, USA.
Marciello
Michael A
MA
Brain
Carlos
C
Ahangar
Brian
B
Burke
David T
DT
D000368:Aged; D000925:Anticoagulants / Q000008:administration & dosage*; D001281:Atrial Fibrillation / Q000188:drug therapy; D001900:Boston; D004311:Double-Blind Method; D016903:Drug Monitoring / Q000379:methods; D004360:Drug Therapy, Computer-Assisted / Q000379:methods*; D005260:Female; D006801:Humans; D019934:International Normalized Ratio; D007902:Length of Stay; D008297:Male; D009518:New York; D010043:Outcome and Process Assessment, Health Care; D012047:Rehabilitation Centers; D020521:Stroke / Q000188:drug therapy; D014652:Vascular Diseases / Q000188:drug therapy* / Q000534:rehabilitation; D020246:Venous Thrombosis / Q000188:drug therapy; D014859:Warfarin / Q000008:administration & dosage*
D000925:Anticoagulants; D014859:Warfarin