title: Tubeless percutaneous renal surgery in obese patients.
abstract: OBJECTIVE
  To assess the outcome and safety of tubeless percutaneous renal surgery in overweight and obese patients.
  
  
  METHODS
  A single urologist performed tubeless percutaneous renal surgery on a total of 138 renal units in 133 patients from March 1996 to January 2003. The tubeless procedures consisted of either nephrolithotripsy or endopyelotomy. We analyzed the clinical data of a subset of these patients who were of considered normal weight (body mass index [BMI] 18.5 kg/m2 or greater but less than 25 kg/m2), overweight (BMI 25 kg/m2 or greater but less than 30 kg/m2), obese (BMI 30 kg/m2 or greater but less than 40 kg/m2), and morbidly obese (BMI 40 kg/m2 or greater).
  
  
  RESULTS
  Of the 133 patients, 5 (3.8%) were considered morbidly obese, 28 (21.1%) were considered obese, 55 (41.4%) were considered overweight, and 45 (34%) were considered to be of normal weight. Of the 133 patients, 104 underwent percutaneous stone extraction and 29 underwent percutaneous antegrade endopyelotomy. Using unpaired t testing, BMI was compared with the transfusion rates, days of hospitalization, and stone-free outcome. The stone group did not demonstrate statistically significant relationships between BMI and transfusion rate, length of hospitalization, and stone-free outcome (P = 0.423, P = 0.105, and P = 0.127, respectively). A stone-free rate of 94.5% was achieved. In the endopyelotomy group, 29 patients were analyzed. Follow-up showed 24 patients (82.8%) had successful resolution of the ureteropelvic junction obstruction 1 year postoperatively. Two patients required readmission for gross hematuria and low hematocrit. One patient required selective angiographic embolization of a pseudoaneurysm.
  
  
  CONCLUSIONS
  Tubeless percutaneous renal surgery is a safe and effective procedure in overweight, obese, and morbidly obese patients.
authors.affiliation: Department of Urology, Kaiser-Permanente Medical Center, Los Angeles, California 90027, USA.
authors.forename: Ronald M
authors.initials: RM
authors.lastname: Yang
authors.forename: Gary C
authors.initials: GC
authors.lastname: Bellman
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D015897:Comorbidity; D005260:Female; D006801:Humans; D007669:Kidney Calculi / Q000209:etiology / Q000601:surgery; D007674:Kidney Diseases / Q000453:epidemiology* / Q000601:surgery*; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D009403:Nephrostomy, Percutaneous / Q000295:instrumentation* / Q000379:methods / Q000706:statistics & numerical data; D009765:Obesity / Q000453:epidemiology*; D009767:Obesity, Morbid / Q000453:epidemiology; D016896:Treatment Outcome; D014546:Urinary Catheterization; D013520:Urologic Surgical Procedures / Q000706:statistics & numerical data*