Abstract
Introduction: Blood loss is a major concern following total knee arthroplasty (TKA) frequently resulting in blood transfusions postoperatively. Various strategies exist to reduce blood loss and allogenic transfusion requirements. This study investigates the effect of immediate postoperative flexion on blood loss and transfusion requirements following TKA.
Methods: 180 consented patients undergoing primary TKA by a single surgeon were enrolled into a prospective randomised controlled study. 90 patients were randomised to have the operated knee nursed in extension postoperatively, and 90 patients to have the knee nursed in flexion for six hours postoperatively. Both groups followed a strict transfusion protocol. Data collected included calculated pre- and postoperative haemoglobin and haematocrit which was used to calculate total blood loss. Units transfused and postoperative complication rates were also recorded.
Results: There was no significant difference in demographics or factors predisposing to bleeding between the groups. The mean total blood loss was 1841mls for those in the extension group compared with 1587mls in the flexion group (p=0.02). The mean number of units transfused in the extension group was 0.78 units/patient compared with 0.36 units/patient in the flexion group (p=0.004). There was no significant difference in pain scores between the groups (p= 0.62).
Conclusion: This study shows that the use of immediate postoperative flexion significantly reduces calculated total blood loss and transfusion rates following TKA.
Correspondence should be addressed to Mr Tim Wilton, BASK at the Royal College of Surgeons, 35–43 Lincoln’s Inn Fields, London WC2A 3PE.
