[Algorithm for diagnosis and prevention of postoperative deep vein thrombosis].

An algorithm is described in this paper for diagnosis and prevention of postoperative deep venous thrombosis. It is presented in the form of a network graph and is based on an evaluation of the relative risk of pulmonary embolism of 17.785 patients. Age above 60 years, malignant disease, and more than four days of postoperative immobilisation were found to be the greatest risk factors for lethal embolism of the pulmonary artery. Examination of the venous flow bed by non-invasive methods has proved to be indicated for any patient who has not resumed spontaneous movement on the fourth postoperative day. Diagnostic coverage has so far been achieved for 75 per cent of all patients still immobilised four days after surgery. Peroral or rectal administration of aspirin (1.5 g:24 h-1) is recommended for its good therapeutic effectiveness to reduce complications and for economic reasons.