title: Delayed postpercutaneous nephrolithotomy hemorrhage: prevalence, predictive factors and management.
abstract: OBJECTIVE
  The aim of this study was to assess the prevalence, potential risk factors and management of delayed post-percutaneous nephrolithotomy (PCNL) bleeding.
  
  
  METHODS
  Records of 2512 patients who had undergone PCNL from April 2008 to April 2011 were reviewed retrospectively. The prevalence of delayed post-PCNL hemorrhage and correlation of different variables such as age, body mass index, stone location and burden, surgical approach, type and number of access ports, type of drainage, comorbidities and previous history of stone surgery with postoperative bleeding were assessed. The efficacy of conservative management and need for angioembolization were analyzed.
  
  
  RESULTS
  In total, 2304 patients [1562 men (67.8%) and 742 women (32.2%)], with a mean age of 46.4 ± 13.6 years (range 17-86 years), were enrolled in the study. The prevalence of delayed hemorrhage was 2.6% (61 patients) and the mean time to the onset of hemorrhage after PCNL was 5.8 days (range 3-11 days). Of 61 patients presenting with delayed hemorrhage, only 16 patients received a blood transfusion. Eight patients underwent angiography because of uncontrolled bleeding and only three underwent embolization. No significant association was found between other variables and post-PCNL hemorrhage, except for type of drainage, in that tubeless surgery increased the rate of postoperative bleeding.
  
  
  CONCLUSIONS
  Delayed hemorrhage is an uncommon complication following PCNL that can be successfully managed with conservative management; only a few patients will require angiography and then embolization. Tubeless PCNL significantly predicted the occurrence of severe postoperative bleeding.
authors.affiliation: Shahid Labbafinejad Medical Center, Urology and Nephrology Research Center, Shahid Beheshti University of Medical Sciences (SBMU) , Tehran, IR , Iran.
authors.forename: Akbar
authors.initials: A
authors.lastname: Nouralizadeh
authors.forename: Seyed Amir Mohsen
authors.initials: SA
authors.lastname: Ziaee
authors.forename: Seyed Hossein
authors.initials: SH
authors.lastname: Hosseini Sharifi
authors.forename: Abbas
authors.initials: A
authors.lastname: Basiri
authors.forename: Ali
authors.initials: A
authors.lastname: Tabibi
authors.forename: Farzaneh
authors.initials: F
authors.lastname: Sharifiaghdas
authors.forename: Hossein
authors.initials: H
authors.lastname: Zaki
authors.forename: Mohammad Masoud
authors.initials: MM
authors.lastname: Nikkar
authors.forename: Alireza
authors.initials: A
authors.lastname: Lashay
authors.forename: Ali
authors.initials: A
authors.lastname: Ahanian
authors.forename: Mohammad Hossein
authors.initials: MH
authors.lastname: Soltani
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009403:Nephrostomy, Percutaneous / Q000009:adverse effects*; D019106:Postoperative Hemorrhage / Q000453:epidemiology* / Q000209:etiology / Q000628:therapy*; D015995:Prevalence; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D055815:Young Adult