[Questionnaire on venous thromboembolism prevention by low molecular weight heparin in medical environment]

The aim of this prospective study was to observe the prescription of low-molecular weight heparin (LMWH) for the prophylaxis of venous thromboembolic disease in medical patients.

We included all the patients on LMWH prophylaxis in 5 medical departments of Sainte-Marguerite Hospital in Marseille. The study described the reasons for this prophylaxis, the thrombotic risk, the follow-up quality and the side-effects.

During four months, 189 (14.3%) of 1317 medical patients have received a prophylaxis with LMWH; sixty one per cent of them were older than 70 years. Thrombotic risk as measured with Thilly's score was low in 50 patients (26%), moderate in 81 patients (43%), high in 58 patients (31%). Platelet count follow-up was optimal in 88 patients (47%). A decrease of platelet count over 30%, reaching less than 100 G/l, was recorded in 4 patients. A venous thrombosis was diagnosed clinically in one patient. Two patients had an overt severe bleeding. A serious hidden bleeding was suspected in 11 patients.

LMWH were frequently prescribed for the prophylaxis of venous thromboembolic disease in medical patients. Most of these patients were over 70 years of age. Platelet count follow-up was in accordance with guidelines in less than half of the patients. Bleedings were not rare on this treatment. The present work suggests that a precise thrombotic risk assessment is needed before the onset of this therapy and that the association with aspirin should be careful.