Transfusion practice in primary unilateral total knee replacement arthroplasty; The need for guidelines

Background and Aims: There are no universally accepted guidelines for blood transfusion in primary, unilateral Total Knee Replacement Arthroplasty (TK A). Transfusion is associated with post-operative infection, fluid overload and prolonged duration of hospitalisation. Due to this morbidity and repor ts of "inappropriate" transfusion practice, an audit of the local practice was organised, with the aim of assessing compliance to existing evidence. Methods: A 1-year retrospective survey of blood transfusion practice was co nducted for all consecutive elective, primary, unilateral TKA operations. Results: 169 operations were performed; 96 % for osteoarthritis; mean patie nt age was 69 years; 66 % were females; 34 % of the patients were transfuse d, 60 % intra-operatively. There was no threshold of pre-operative Hb predi ctive of a transfusion and no significant difference in the pre-operative H b between transfused and non-transfused groups. Only 26 % of the cross-matc hed blood was eventually transfused. Intra-operative blood loss was negligi ble and only 10 % of transfused patients had shown cardiovascular instabili ty. The post-operative Hb drop was maximal at around day-4. Conclusions: The lack of guidelines has led to inconsistent local transfusi on practice, often with no scientific evidence to support it. In the absenc e of a randomised controlled trial addressing the issue, certain transfusio n guidelines are suggested, based on existing indirect scientific evidence.