Thrombosis prophylaxis in medical patients: a retrospective review of clinical practice patterns.

BACKGROUND AND OBJECTIVES The risk of venous thromboembolism in medical patients is comparable to the risk in general surgical patients. Thromboprophylaxis is recommended for specific medical patients, but its use in clinical practice is unknown. DESIGN AND METHODS We conducted a retrospective review of the charts of consecutive patients discharged from 2 departments of Internal Medicine, one in the teaching hospital of Varese and one in the non-teaching hospital of Angera, Italy, from October to December 2000. We selected the charts of patients with clinical conditions at increased risk of venous thromboembolism requiring thromboprophylaxis according to consensus statements. The use of antithrombotic drugs and contraindications to prophylaxis were documented. RESULTS We screened a total of 516 charts, 265 in Varese and 251 in Angera and we identified 165 patients (103 and 62, respectively) at risk of venous thromboembolism because of malignancy (53), heart failure (34), stroke (33), acute infections (23), acute respiratory failure (18), acute rheumatic disorders (3), and inflammatory bowel disease (1). Forty-two patients had contraindications to antithrombotic drugs and 11 were already on long-term oral anticoagulant treatment. Among the 112 remaining patients, prophylaxis was prescribed to 52 patients (46.4%), 35 of 60 in Varese (58.3%) and 17 of 52 in Angera (32.7%, p=0.0067). Patients with stroke and heart failure were significantly more likely to receive thromboprophylaxis than other groups of patients. INTERPRETATION AND CONCLUSIONS Prophylaxis of venous thromboembolism is underused in medical patients and the proportion of patients receiving antithrombotic drugs varies with the medical condition which precipitated hospital admission. The low rate of usage of prophylaxis suggests that preventable cases of thromboembolism are occurring and that better education of physicians is required to increase the usage of thromboprophylaxis.