151 patients were randomized to use of an autotrasfusion system for washed shed blood (WSB) or to a regular drain without suction to determine if the autotransfusion system reduced the need for allogenic blood transfusions after total knee arthroplasty. The number of patients requiring blood transfusion and the total number of transfused units did not defer between the two techniques. Hence, the use of autotransfusion systems was deemed to be no more effective than the use of a regular drain without suction in terms of reducing the need for allogenic blood transfusion.