title: Residual air persists in the renal collecting system following percutaneous nephrolithotomy.
abstract: OBJECTIVE
  To determine the presence or absence of air in the renal collecting system 48 hours following percutaneous nephrolithotomy (PCNL).
  
  
  METHODS
  The study was based on a review of the records of the last 100 consecutive patients undergoing PCNL for stone extraction. Two urologists and a uroradiologist reviewed post-PCNL nephrostogram films and determined the presence or absence of air in the urinary tract.
  
  
  RESULTS
  Nephrostography was routinely performed 48 hours after PCNL, and all films of the 100 patients were reviewed. Gas was detected in 98 (98%) of the 100 cases that appeared as gas pyelograms outlining the renal calyces. Of the 98 cases, 33 (34%) demonstrated gas in the upper calyx, 10 (10%) in the middle calyx, 12 (13%) in the lower calyx, and 43 (44%) in more than one calyx. Gas was not detected in the renal parenchyma or perirenal areas.
  
  
  CONCLUSIONS
  Gas is present within the renal collecting system 48 hours after a percutaneous procedure. Prospective studies should be performed to document the amount of time needed for complete resolution of gas from the collecting system.
authors: Department of Urology, Albert Einstein College of Medicine, Long Island Jewish Medical Center Campus, New Hyde Park, New York 11040, USA.
authors: Joel Patrick A
authors: JP
authors: Aldana
authors: Benjamin R
authors: BR
authors: Lee
authors: Won J
authors: WJ
authors: Lee
authors: Assaad
authors: A
authors: El-Hakim
authors: Robert
authors: R
authors: Marcovich
authors: Arthur D
authors: AD
authors: Smith
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004618:Embolism, Air / Q000209:etiology*; D005119:Extravasation of Diagnostic and Therapeutic Materials / Q000209:etiology / Q000601:surgery; D005260:Female; D006801:Humans; D007431:Intraoperative Complications / Q000209:etiology / Q000601:surgery; D007669:Kidney Calculi / Q000601:surgery*; D007685:Kidney Tubules, Collecting / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009403:Nephrostomy, Percutaneous; D011183:Postoperative Complications / Q000209:etiology*; D016896:Treatment Outcome