[Clinical and in-vitro studies of the therapeutical range of acetylsalicylic-acid to prevent deep vein thrombosis (author's transl)].

In three consecutive studies, acetylsalicyliclysine using the dosages 0.9 g/48 h, 1.8 g/24 h and 3.6 g/24 h, was examined in order to see its effect in preventing deep vein thrombosis (DVT) after elective hip joint surgery. DVT was diagnosed by the 125-i-fibrinogen-test. No reduction of postoperative DVT was found under any of the administered AS-lysine dosages. The collagen-induced platelet aggregation was significantly decreased in all three groups. However, under the low AS-lysine dosages, aggregation was less inhibited with the incidence of DVT than without DVT. In the group with the 3.6 g-dosage, aggregation was maximally inhibited, without any significant difference related to the occurrence of DVT. The results reveal no therapeutic range of AS-lysine to prevent postoperative venous thrombosis.