We compared allogeneic blood usage for two groups of patients undergoing to
tal knee replacement surgery (TKR). Patients were randomized to receive eit
her their post-operative wound drainage as an autotransfusion (n=115) after
processing or to have this wound drainage discarded (n=116). Allogeneic bl
ood was transfused in patients of either group whose haemoglobin fell below
9 g dl(-1). Only 7% of patients in the autotransfusion group required an a
llogeneic transfusion compared with 28% in the control group (P <0.001). Th
ere was no hospital mortality and only 3% mortality from all causes at the
study completion, which spanned 6 months to 3 yr. There was a higher incide
nce of infection requiring intervention in the allogeneic group (P <0.036).
Total patient costs were pound 113 greater in the autotransfusion group. W
e conclude that in this type of surgery post-operative cell salvage is a sa
fe and effective method for reducing allogeneic blood use.