Closed suction drains do not increase the blood transfusion rates in patients undergoing total knee arthroplasty.

We aim to determine whether the presence of a drain increases the actual blood transfusion rates in patients undergoing primary total knee arthroplasty (TKA). A retrospective review was performed on two consecutive groups of patients who underwent primary TKA: group 1 including 100 patients who underwent TKA and had one deep closed suction drain; group 2 including 100 patients who underwent TKA and had no drain. Blood transfusions were given post-operatively on the basis of clinical need without a pre-determined haemoglobin trigger factor. Group 1 drained a mean of 692 ml (range 150-1500) of blood in 48 h. The mean fall in haemoglobin at 48 h post-operatively was 3.26 g/dl in group 1 and 3.33 g/dl in group 2. Nine patients in group 1 and seven patients in group 2 required a blood transfusion; this was not statistically significant (P=0.79). Transfusion of primary TKA patients on the basis of clinical need can result in post-operative transfusion rates of 8%. The presence of a drain does not increase the transfusion rates of patients undergoing primary TKA.