We investigated Danaparoid Sodium (Orgaran) as anticoagulant using three different concentrations (9, 4,5 or 3 U/ml anticoagulant solution) for the use in the autotransfusion device Cell Saver 5 (Haemonetics). Fresh units of whole blood packs were mixed in the reservoir in a proportion of 5:1 with the anticoagulant solution. Having started the Cell Saver 5 in the automatic mode, the amount of Danaparoid in the retransfusion blood was determined (chromogenic Antifactor-Xa test). The lowest concentration of the anticoagulant was applied in 4 patients with Heparin-induced Thrombocytopenia Type II undergoing total hip arthroplasty. There was a correlation between the concentration in the reservoir and in the retransfusion blood. None of the patients showed a disturbance of his coagulation system. One of them had slight clotting in the reservoir. We recommend the use of the lower concentrations tested: 4,5 U/ml or, particularly for patients with renal insufficiency or low body weight or expected high retransfusion volumes, 3 U/ml as anticoagulant concentrations. If the autotransfusion device is used according to the manufacturer's instructions there may be virtually no risk of clotting in the Cell Saver or of inhibition of the coagulation system in the patient.