title: Systematic review and meta-analysis of percutaneous nephrolithotomy for patients in the supine versus prone position.
abstract: OBJECTIVE
  To evaluate the efficacy and safety of percutaneous nephrolithotomy (PCNL) for patients in the supine position vs prone position.
  
  
  METHODS
  Eligible studies were identified from electronic databases (Cochrane CENTRAL, Medline and EMBASE). The database search, quality assessment, and data extraction were independently performed by two reviewers. Efficacy (stone-free rate, operative time) and safety (complication, such as fever and transfusion rate) were explored by using Review Manager 5.0. Sensitivity analysis was performed to explore the influence of low-quality studies.
  
  
  RESULTS
  Two randomized controlled trials and two case-control studies including 389 patients met the inclusion criteria. Meta-analysis of extractable data showed that PCNL in the supine position was associated with a significantly shorter operative time than PCNL in the prone position (mean difference: -24.84; 95% confidence interval [CI]: -34.45 to -15.23; P < 0.00001). There was no difference between the positions with regard to success rate (odds ratio [OR]: 1.16; 95% CI: 0.68-1.48; P = 0.59), complication (OR: 1.09; 95% CI: 0.67-1.80; P = 0.72), transfusion rate (OR: 2.19; 95% CI: 0.93-5.13; P = 0.07), and fever rate (OR: 0.39; 95% CI: 0.13-1.16; P = 0.09).
  
  
  CONCLUSIONS
  PCNL in the supine position took a shorter operative time than the prone position, but both positions appeared to be equivalent with regard to the stone-free rate and complication rate, transfusion rate, and fever rate. In brief, PCNL in the supine position is as effective and safe as PCNL in the prone position and was an alternate option for removal of renal calculi in PCNL.
authors.affiliation: Department of Urology, West China Hospital, Sichuan University, Chengdu, Sichuan, People's Republic of China.
authors.forename: Liangren
authors.initials: L
authors.lastname: Liu
authors.forename: Shuo
authors.initials: S
authors.lastname: Zheng
authors.forename: Yong
authors.initials: Y
authors.lastname: Xu
authors.forename: Qiang
authors.initials: Q
authors.lastname: Wei
mesh_terms: D000328:Adult; D000368:Aged; D006801:Humans; D008875:Middle Aged; D009403:Nephrostomy, Percutaneous / Q000009:adverse effects / Q000379:methods*; D011183:Postoperative Complications / Q000209:etiology; D016684:Prone Position; D016683:Supine Position; D016896:Treatment Outcome