title: Comparative analysis of percutaneous nephrolithotomy in patients with and without a history of open stone surgery: single center experience.
abstract: OBJECTIVE
  To report our experience of percutaneous nephrolithotomy (PCNL) in patients who were treated previously with open stone surgery.
  
  
  METHODS
  Sixty-six patients with a history of open stone surgery (group 1) were compared with 90 patients without previous surgical intervention (group 2). Both groups were almost similar in demographic profile (age, sex, laterality, stone burden and success rate, body mass index, and location of stones. Patients who had tubeless or bilateral PCNL were excluded from the study. Antibiotics were administered prophylactically to all the patients. Patients with positive urine culture were treated with appropriate antibiotics, and sterile urine was ensured before surgery. Normal saline was used as irrigation fluid. Statistical analysis was performed using the chi-square test for qualitative variables and the Student t test for quantitative variables. A P value <0.05 was considered significant.
  
  
  RESULTS
  Mean time interval between previous open surgery to PCNL in group 1 was 7.6 (range 1-18) years. Mean operative time was longer in group 1 (88.4 min vs 80.2 min), but it was not statistically significant. Average drop in hemoglobin level was comparable in both groups (2.3 vs 2.1 g/dL). A significant number of patients in group 1 needed a metallic dilator for tract dilation. Hospital stay and postoperative analgesic requirement were similar in both groups. Postoperative and intraoperative complications were also similar in both groups.
  
  
  CONCLUSIONS
  Previous open stone surgery does not alter the outcome of subsequent PCNL significantly except that these patients more frequently need relook procedures for achieving complete clearance.
authors.affiliation: Department of Urology, All India Institute of Medical Sciences, New Delhi, India. narmadagupta@hotmail.com
authors.forename: N P
authors.initials: NP
authors.lastname: Gupta
authors.forename: Saurabh
authors.initials: S
authors.lastname: Mishra
authors.forename: Rishi
authors.initials: R
authors.lastname: Nayyar
authors.forename: Amlesh
authors.initials: A
authors.lastname: Seth
authors.forename: Ajay
authors.initials: A
authors.lastname: Anand
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D003710:Demography; D005260:Female; D006801:Humans; D007669:Kidney Calculi / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D009403:Nephrostomy, Percutaneous