RESUMO
BACKGROUND: Bilateral total knee arthroplasty is associated with significant blood loss. Postoperative anaemia retards patients recovery, and blood transfusion increases the risk for major complications including infection. While strategies like hypotensive anaesthesia, tranexamic acid, bone wax and so on are useful to conserve blood, navigation has also shown to decrease blood loss and transfusion in unilateral knee arthroplasty. The aim of this study was to compare the blood loss and transfusion in sequential bilateral knee arthroplasty performed with or without navigation. MATERIALS AND METHODS: A retrospective case control cohort study of sequential bilateral knee arthroplasties was performed between 2 groups of 77 patients each, group N operated with navigation and group M operated without navigation. Both groups were matched for age, sex and body mass index. All patients were operated with similar surgical technique. The two cohorts were compared for blood loss calculated by three reliable methods. RESULTS: The preoperative haemoglobin (Hb) in group N was 12.83 ± 1.32 and group M was 12.58 ± 1.33 ( p = 0.24). The postoperative Hb taken day 4 before any blood transfusions was 8.60 ± 1.24 in group N and 8.54 ± 1.16 in group M ( p = 0.75). The average fall in Hb was 4.23 ± 1.08 in group N and 4.04 ± 1.19 in group M ( p = 0.31). There was no difference in blood loss between group N and M in all three methods; Gross equation ( p = 0.56), Hb dilution ( p = 0.24) and Hb balance ( p = 0.20). Need for blood transfusion was similar in group N and M ( p = 0.56). CONCLUSION: Blood loss and transfusion are equivalent in sequential bilateral total knee arthroplasty perform with or without navigation.
