Use of venous thromboembolism prophylaxis for surgical patients: A multicentre analysis of practice in Spain

Objective: To assess the use of venous thromboembolism prophylaxis in surgi cal patients. Design: Retrospective multicentre study. Setting: Eight acute-care teaching hospitals with more than 400 beds, Spain . Patients: Medical records of all consecutive patients undergoing operations in the general surgical and trauma and orthopaedic services during the mon th of April, 1997, were randomly selected. Intervention: The sample size for each type of operation (general, trauma-o rthopaedic) was calculated from the number of operations done at each hospi tal (with an absolute precision of 5%, and an alpha error of 5%) and the pr evalence of the use of venous thromboembolism prophylaxis obtained from a r andom sample of 50 records (25 from patients in general surgery and 25 from patients in orthopaedic surgery) from each centre. Main outcome measures: Appropriate and inappropriate pharmacological prophy laxis defined according to a combination of risk categories for venous thro mboembolism, doses of antithrombotic agents given, time of starting prophyl axis, and its duration. Results: A total of 1848 medical records (general surgery, n = 1025; trauma -orthopaedic surgery, n = 823) were included. Physical methods (elastic sto ckings, intermittent pneumatic compression) were used in only 0.3% of patie nts. Pharmacological prophylaxis consisted of low molecular weight heparin in 99% of cases. The percentage given heparin-based prophylaxis was 54%. Ov erall, appropriate prophylaxis was given in 1175 patients (64%). Use of thr omboprophylaxis ranged from 27% to 70% among the participating hospitals. P rophylaxis was more Likely to be appropiate in orthopaedic patients (577, 7 0%) than in general surgical patients (598, 58%) in both the high and moder ate risk categories. Conclusions: Given the large variability between the participating hospital s, more specific protocols and recommendations about prophylaxis of thrombo embolism in surgical patients are needed.