[Inappropriate prescription of heparin at curative doses in the hospital. Can the information to prescribing physicians decrease misuse?].

To control whether prescriptions of curative doses of heparin (non fractioned heparins, enoxaparin, tinzaparin) in the hospital complied with the official recommendations; to provide the physicians with information adapted to the recorded misuse and to evaluate the influence of this information. A prospective study was conducted between May and October 1999 on the prescriptions of 20 residents from 6 services in 3 phases: phase P1 with initial evaluation (particularly on the indications for heparin, the molecule administered, initial dose and monitoring), phase P2 with analysis and diffusion of an adapted information and phase P3 with final evaluation. 111 inpatients were included in the phase P1 (66.7% aged over 75 years, 18.9% with creatinin clearance below 30 ml/mn) and 101 inpatients were included in the phase P3 (56.4% aged over 75 years, 10.8% with renal failure). During phase P1: among the prescriptions of low molecular weight heparin (LMWH) 54.3% did not comply with the official recommendations; initial doses were too high in 15.3% of patients; mean initial doses of LMWH were not adapted to age, weight or creatinin clearance. Only 58.5% of patients had their platelets monitored. On the other hand, 15.3% of patients exhibited heparin side effects. During phase P3, the main modifications in prescriptions were a reduction in inappropriate indications for LMWH, reduction in LMWH prescriptions in patients aged over 75 or with excessive body weight or with renal failure, and increased platelet monitoring, but without significant difference. On the other hand, mean initial doses of each heparin were not modified. Heparin complications decreased but not significantly. This study highlights a real context of heparin prescription at curative doses, often differing from clinical studies, particularly with regards to age, renal failure and comorbidity; prescriptions often unadapted to official recommendations on indications, dose and monitoring; a real but limited influence of appropriate information for the physicians, which partially depends on the accuracy of official recommendations, particularly in patients with increased hemorrhagic risk.