Background: Whether to cross match or simply group and save for a primary THR is still a matter of debate. The argument in favour of cross match being immediate availability of blood and against it being wastage of resources, underutilization of cross matched samples etc.

Patients & Methods: We retrospectively analyzed the records of 136 patients who underwent primary THR at Manchester Royal Infirmary in 2004.

Result: Of the 136 patients, 104 had 220 units of blood cross matched. The average blood loss was 520 mls. The average pre op. Hb level was 12.8 g/dl while the average post op. Hb levels at 1, 3 & 5 days were 9.4, 9.9 & 10.1 gms/dl resply. Blood loss in patients on pre op. anticoagulant treatment (n = 44) was 596 mls while in the rest, it was 502 mls. The drop in Hb levels between the 2 groups was 3.6 gms/dl and 3.1 gms/dl resply. Patients with drain had an average drop in Hb level of 3.5 gms while it was 3.1 gms in others. The overall transfusion rate was 43.7 %. The most common reason for transfusion was asymptomatic low Hb (< 8 g/dl). Out of the 220 cross matched units, 99 (44.8 %) were transfused. Various probabilities like Cross-match to Transfusion ratio, Transfusion Probability & Transfusion Index were used to find out whether the cross matched units are used effectively.

Discussion: The only factor which influenced the transfusion rate was pre-op. Hb value. 79 %of patients required transfusion when pre op. Hb level was < 12 gm/dl.

Conclusion: 1. Group & Save is a safe policy for primary THR’s 2. Cross match only for patients with Hb of < 12gms/ dl. 3. Consider oral/IV iron therapy, autologous blood transfusion and retransfusion drain 4. Use of Aprotinin and transanamic acid reduces bleeding during surgery.