title: Post-percutaneous nephrolithotomy extensive hemorrhage: a study of risk factors.
abstract: OBJECTIVE
  We identified risk factors predicting severe bleeding due to percutaneous nephrolithotomy.
  
  
  METHODS
  Computerized data on 2,909 patients who underwent a total of 3,878 percutaneous nephrolithotomy procedures between January 1995 and December 2005 were retrospectively reviewed. Data on patients who experienced severe bleeding requiring angiographic renal embolization were compared with those on other patients using univariate and multivariate analyses. We tested the characteristics of patients, kidneys and stones together with details of the operative procedure and surgeon experience.
  
  
  RESULTS
  Severe bleeding complicated a total of 39 procedures (1%) in 25 males and 14 females with a mean age of 50.7 +/- 12.6 years. Associated morbidity included shock in 6 patients and perirenal hematoma in 4. Renal angiography revealed pseudoaneurysm in 20 patients, arteriovenous fistula in 9, the 2 lesions in 8 and arterial laceration in 2. Bleeding could be controlled with superselective embolization in 36 patients (92.3%). Followup was available on 33 patients (mean 21 +/- 15 months). Renal function was stable in all patients except 3 who had a post-embolization increase in serum creatinine, of whom all had a solitary kidney and none required renal replacement therapy. Significant risk factors for severe bleeding were upper caliceal puncture, solitary kidney, staghorn stone, multiple punctures and inexperienced surgeon.
  
  
  CONCLUSIONS
  Percutaneous nephrolithotomy should be performed by an experienced endourologist in patients at risk for severe bleeding, such as those with a solitary kidney or staghorn stones.
authors.affiliation: Urology Department, Urology and Nephrology Center, Mansoura University, Mansoura, Egypt.
authors.forename: Ahmed R
authors.initials: AR
authors.lastname: El-Nahas
authors.forename: Ahmed A
authors.initials: AA
authors.lastname: Shokeir
authors.forename: Ahmed M
authors.initials: AM
authors.lastname: El-Assmy
authors.forename: Tarek
authors.initials: T
authors.lastname: Mohsen
authors.forename: Ahmed M
authors.initials: AM
authors.lastname: Shoma
authors.forename: Ibrahim
authors.initials: I
authors.lastname: Eraky
authors.forename: Mahmoud R
authors.initials: MR
authors.lastname: El-Kenawy
authors.forename: Hamdy A
authors.initials: HA
authors.lastname: El-Kappany
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004621:Embolization, Therapeutic / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009403:Nephrostomy, Percutaneous / Q000009:adverse effects*; D019106:Postoperative Hemorrhage / Q000628:therapy*; D011859:Radiography; D012077:Renal Artery / Q000000981:diagnostic imaging; D012189:Retrospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index