title: The effect of peri-operative blood loss on postoperative pain following total knee arthroplasty.
abstract: OBJECTIVE
  This study aimed to investigate a possible link between peri-operative blood loss and post-operative pain following primary total knee arthroplasty (TKA).
  
  
  METHODS
  A retrospective study was carried out using data from two RCTs (403 patients). Blood loss was estimated using Gross et al's formula. Blood transfusions were factored into calculations. Pain scores were obtained using a visual analogue score.
  
  
  RESULTS
  Multiple regression analysis showed no relationship (0.09) and analysis of variance showed no significant difference (p = 0.597). Null hypothesis accepted.
  
  
  CONCLUSIONS
  Minimising blood-loss remains an important goal during surgery. On-going efforts should be made to improve patient satisfaction following TKA.
authors.affiliation: Outcomes Department, Musgrave Park Hospital, Belfast BT9 7JB, UK.
authors.forename: Paul
authors.initials: P
authors.lastname: Hegarty
authors.affiliation: Outcomes Department, Musgrave Park Hospital, Belfast BT9 7JB, UK.
authors.forename: Seamus
authors.initials: S
authors.lastname: O'Brien
authors.affiliation: Statistical Advisory Committee, Queen's University Belfast, Belfast BT7 1NN, UK.
authors.forename: Mike
authors.initials: M
authors.lastname: Stevenson
authors.affiliation: Outcomes Department, Musgrave Park Hospital, Belfast BT9 7JB, UK.
authors.forename: David
authors.initials: D
authors.lastname: Beverland
keywords: Arthroplasty; Blood loss; Pain; Patient satisfaction; TKA