Background. Total Knee Replacement (TKR) is one of the most common surgeries in our speciality, with a high risk of significant blood loss and consequent transfusion. The drain clamping is usually applied to reduce both blood loss and transfusion in this procedure. However, this method is still somewhat controversial too. Method. We performed a prospective randomised study of 74 patients with advanced knee osteoarthritis. All were treated in our centre with TKR. The patients were randomly assigned into two groups. In group A we included patients whose drainage system was clamped temporarily (during the first 6 postoperative hours). Group B includes those patients in who we use traditional system, with continuous suction drain that was placed after surgery. Results. A statistically significant difference in haemoglobin loss after surgery was found, with 0.83 g/dl less decline in patients with temporary clamping drains. The decrease of haematocrit levels, the blood loss or the number of transfusions were lower in the temporary clamping group, but without statistic significance. No cases with wound infection neither clinical venous thromboembolism were detected in our group. Conclusions. These results suggest that drainage clamping during the first 6 postoperatative hours reduces the
