title: Impact of previous open renal surgery on the outcomes of subsequent percutaneous nephrolithotomy: a meta-analysis.
abstract: OBJECTIVE
  The aim of this study was to systematically compare the perioperative outcomes of percutaneous nephrolithotomy in patients with or without previous ipsilateral open renal surgery (POS).
  
  
  METHODS
  Systematic searches of the PubMed, Web of Science and Cochrane Library databases were used to identify relevant studies, and, following literature screening and data extraction, a meta-analysis was performed.
  
  
  RESULTS
  17 retrospective cohort studies involving 4833 procedures (4784 patients) were included. No statistically significant differences were observed between patients with or without POS in terms of supracostal access; single/multiple tracts; metal dilator need; time required to access the collecting system; fluoroscopic duration; demand for analgesics; hospital stay; final stone-free rate; and risk of developing certain complications (eg, fever, haemorrhage, haemo/hydro/pneumothorax, blood transfusion, urinary tract infection and sepsis) as well as regarding the risk of total complications. Patients with POS, however, had a greater drop in haemoglobin (weighted mean difference (WMD), 1.78 g/L; 95% CI 1.09 to 2.47; p<0.00001) and higher risk of bleeding that required angiographic embolisation (relative risk (RR), 3.73; 95% CI 1.36 to 10.21; p=0.01). In addition, patients with POS also had a lower initial stone-free rate (RR, 0.96; 95% CI 0.92 to 0.99; p=0.007) and more secondary treatment (RR, 1.61; 95% CI 1.09 to 2.37; p=0.02). Sensitivity analysis produced comparable results except for differences in operative time and initial stone-free rate, which did, however, prove to be statistically insignificant (p=0.16 and 0.69, respectively).
  
  
  CONCLUSIONS
  Current evidence suggests that percutaneous nephrolithotomy in patients with POS is associated with a significantly greater drop in haemoglobin, higher risk of requiring angiographic embolisation and auxiliary procedures, potentially longer operative time, and lower initial stone-free rate than percutaneous nephrolithotomy in patients without POS.
authors.affiliation: Department and Institute of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
authors.forename: Henglong
authors.initials: H
authors.lastname: Hu
authors.affiliation: Department and Institute of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
authors.forename: Yuchao
authors.initials: Y
authors.lastname: Lu
authors.affiliation: Department and Institute of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Cui
authors.affiliation: Department and Institute of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
authors.forename: Jiaqiao
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department and Institute of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
authors.forename: Zhenyu
authors.initials: Z
authors.lastname: Zhao
authors.affiliation: Department and Institute of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
authors.forename: Baolong
authors.initials: B
authors.lastname: Qin
authors.affiliation: Department and Institute of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
authors.forename: Yufeng
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department and Institute of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Department and Institute of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
authors.forename: Shaogang
authors.initials: S
authors.lastname: Wang
mesh_terms: D016063:Blood Loss, Surgical / Q000706:statistics & numerical data*; D006801:Humans; D007669:Kidney Calculi / Q000473:pathology / Q000601:surgery*; D007902:Length of Stay / Q000706:statistics & numerical data; D009403:Nephrostomy, Percutaneous / Q000009:adverse effects*; D061646:Operative Time; D011183:Postoperative Complications / Q000453:epidemiology*; D012189:Retrospective Studies; D012307:Risk Factors
keywords: meta-analysis; nephrolithiasis; open surgery; percutaneous nephrolithotomy