A Prospective Controlled Study of a Computer-Assisted Acenocoumarol Dosage Program

Abstract

The increase in oral anticoagulant (OA) treatment has led to development of new strategies for its control. We tested the efficacy of the GAO software (Dade Behring) in providing adequate acenocoumarol dosages for patients whose international normalised ratios (INRs) were no more than 0.5 points out of range. From December 1998 to August 1999, all outpatients in this setting were randomly assigned to receive computer-generated or traditionally fixed OA doses. Patients in their first 4 weeks of treatment were excluded. Overall, 8,352 dosages were calculated by the computer and 7,586 by the medical staff. The main endpoint of the study was the time spent in target INR range. The computer matched the traditional dosing, achieving a small but statistically significant greater efficacy in maintaining patients within the INR target range. The percentage of INR determinations over 5.5 was very low in both groups. Our results validate the computerised acenocoumarol dosing in our centre, achieving at least similar levels of effectiveness and safety compared with traditional dosage by medical staff.

Dynamics of case-fatalilty rates of recurrent thromboembolism and major bleeding in patients treated for venous thromboembolism

“…This percentage of INR controls in range is similar to the obtained in an observational study including Italian and Spanish patients (the most active countries recruiting patients in RIETE), in which the TTR were 68.9% and 64.4%, respectively (26). Similar estimates were observed in two other studies (27,28). Thus, at least in our setting, the TTR in daily practice would not significantly differ from those observed in the setting of the clinical trials included in the a aforementioned systematic review (11).…”

Evidence-Based Management of Anticoagulant Therapy

“…46,[78][79][80][81][82][83][84][85][86][87][88][89][90][91][92][93][94][95][96][97] These dosing adjuncts have been studied at the initiation of therapy (no prior VKA doses) and during the maintenance phase of therapy and were compared with dose deci sions made without the use of decision support (manual dosing). Both nomogram/computer-assisted and manual dosing were performed by experienced anticoagulation providers in some studies 78,86,87,90,91 and by providers without specialized training (eg, trainee physicians, house staff, regular physician, nurses) in others. 46,[79][80][81][82][83][84][85]88,89,[92][93][94][95] Decision support-guided dosing (paper nomograms or computer programs) performed no better than manual dosing during initiation of VKA therapy in pooled analyses of available RCTs ( Table 7 , Table S7).…”

Approaches to Optimal Dosing of Vitamin K Antagonists

“…1,9 Dosing Nomograms Several reports have summarized experience with computerassisted dosage programs used to assist VKA dosing. [17][18][19][20][21][22][23] Although the use of such software programs is likely increasing, less than 5% of surveyed physicians indicated that they used a computer-assisted dosing program in their usual VKA dosing practices. 24 Use of computer-assisted dosing support increased to 9% when the responsibility for warfarin dosing was delegated to a nonphysician staff member.…”