title: Blood loss closely correlates with body mass index in total hip arthroplasty performed through direct lateral approach.
abstract: OBJECTIVE
  To investigate total blood loss (TBL), intraoperative blood loss (IBL), post-operative drainage (POD), and other related variables in total hip arthroplasty (THA) performed through direct lateral approach.
  
  
  METHODS
  This study was completed in Shanghai Sixth People's Hospital, Shanghai, China, between January and December 2010. We analyzed 113 patients treated by THA through direct lateral approach. Recordable blood loss (RBL) was measured and TBL was calculated according to the Gross formula. Ordinal logistic regression analysis was used for TBL, IBL, and POD, with gender, age, body mass index (BMI), disease duration, and operative time as independent variables.
  
  
  RESULTS
  The average operative time was 51.5 +/- 10.4 (range: 35-70) minutes, with an average RBL of 454 +/- 144 (range: 150-180) ml. Average TBL was significantly higher (975 +/- 355, range: 430-2020 ml; p<0.001). In the analysis of variables, BMI closely correlated with TBL, IBL, and POD, with odds ratios of 4.80 (95% CI: 2.63-8.78 [TBL]), 5.39 (95% CI: 2.84-10.25 [IBL]), and 4.37 (95% CI: 2.43-7.89 [POD]). Moreover, TBL (54.172), IBL (55.198), and POD (39.139) correlated with trend test BMI.
  
  
  CONCLUSIONS
  The TBL, IBL, and POD closely correlate with BMI in patients undergoing THA through direct lateral approach.
authors.affiliation: Department of Orthopedic Surgery, Shanghai Sixth People's Hospital, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Xiao-Wei
authors.initials: XW
authors.lastname: Yu
authors.forename: Zi-Sheng
authors.initials: ZS
authors.lastname: Ai
authors.forename: You-Shui
authors.initials: YS
authors.lastname: Gao
authors.forename: Chang-Qing
authors.initials: CQ
authors.lastname: Zhang
mesh_terms: D000328:Adult; D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000379:methods*; D016063:Blood Loss, Surgical; D001810:Blood Volume; D015992:Body Mass Index; D004322:Drainage; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D061646:Operative Time; D011184:Postoperative Period