Post-operative retransfusion of unwashed filtered shed blood reduces allogenic blood demand in hip hemiarthroplasty in traumatic femoral neck fractures-a prospective randomized trial

Abstract

Purpose: Patients who undergo hip hemiarthroplasty (HHA) due to traumatic femoral neck fracture frequently require red blood cell (RBC) transfusion. Although post-operative autologous blood transfusion (ABT) is well established in elective arthroplasty, its role in trauma patients remains unclear.

Methods: Two hundred twenty-nine patients with a traumatic femoral neck fracture that underwent HHA at our level-I trauma centre between 2005 and 2009 were prospectively randomized to a high-vacuum drainage or an ABT device. In this single-institution analysis, the number of RBC units as well as the amount of retransfused shed blood were recorded and compared according to study groups. Additionally, the significance of confounding factors for allogenic blood demand such as age, gender, pre-operative Hb level, surgical approach, type of prosthesis and amount of intra-operative RBC units were evaluated using multivariate analysis.

Results: One hundred thirty-five patients were randomized in the high-vacuum group while 94 patients received an ABT device. Intention to treat analysis revealed no significant difference in post-operative RBC demand (ABT: 0.87 RBC, high-vacuum drainage: 1.01 RBC; P = 0.374). However, patients that actually received retransfusion (N = 35) had a reduced post-operative RBC demand (0.49 RBC units, P = 0.014).

Conclusion: While only one third of trauma patients treated with an ABT device during HHA actually receive retransfusion, retransfused patients seem to significantly benefit from this treatment as reflected by a reduced pos-toperative RBC demand.

Keywords: Autologous blood transfusion; Femoral neck fracture; Hip hemiarthroplasty; Retransfusion.