Prevention of venous thromboembolism in thoracic and cardiovascular surgery.

Venous thromboembolism is the most preventable illness among patients in hospital. We prepared guidelines for the prophylaxis of venous thromboembolism, based on previous experience of perioperative risk factors. The aim of this study was to evaluate the effectiveness of these guidelines. All 1,467 patients who underwent surgery for thoracic or cardiovascular disease between April 2002 and July 2004, before the prophylactic guidelines were implemented, were assigned to group A. Another 1,389 patients who had surgery between August 2004 and December 2006, after the guidelines had been implemented, formed group B. The incidences of venous thromboembolism perioperatively in the 2 groups were compared. Six (0.4%) patients in group A developed deep vein thrombosis or pulmonary embolism, whereas no patient in group B experienced thromboembolism. The difference between groups was significant, so we consider our guidelines for venous thromboembolism prevention in the perioperative period to be clinically useful.