title: Failure of initial renal arterial embolization for severe post-percutaneous nephrolithotomy hemorrhage: a multicenter study of risk factors.
abstract: OBJECTIVE
  Severe hemorrhage after percutaneous nephrolithotomy is a rare but alarming event. If local tamponade fails to control bleeding, the current treatment of choice is superselective renal arterial embolization. If initial embolization is unsuccessful, repeat embolization or nephrectomy is often required. To our knowledge we report the first study of risk factors for failed initial superselective renal arterial embolization.
  
  
  METHODS
  We retrospectively reviewed the records of 17,619 patients who underwent a total of 19,185 percutaneous nephrolithotomies from January 2007 to April 2012 at 6 centers. Study inclusion criteria were percutaneous nephrolithotomy and severe postoperative renal hemorrhage requiring superselective renal arterial embolization. Data on patients in whom initial embolization failed were compared to those on patients with successful embolization on univariate and multivariate analysis.
  
  
  RESULTS
  Of the 17,619 patients 117 (0.6%), met study inclusion criteria, including 90 males and 27 females. Initial treatment failed in 12 patients (10.3%), 8 underwent repeat superselective renal arterial embolization, 3 required 3 embolizations and 1 underwent nephrectomy. Complete bleeding cessation was achieved in all 11 repeat embolization cases. We identified 3 risk factors for failure of initial superselective renal arterial embolization, including multiple percutaneous access sites, more than 2 bleeding sites identified on renal angiogram and gelatin sponge alone used as the embolic material.
  
  
  CONCLUSIONS
  Carefully selecting patients for multitract percutaneous nephrolithotomy, making an extra effort to identify all bleeding vessels during angiography and not using gelatin sponge as the only embolic material could potentially decrease the risk of failure of initial superselective renal arterial embolization after percutaneous nephrolithotomy.
authors.affiliation: Department of Urology, Minimally Invasive Surgery Center, First Affiliated Hospital of Guangzhou Medical University, Guangdong Key Laboratory of Urology, Guangdong, People's Republic of China. Electronic address: gzgyzgh@vip.tom.com.
authors.forename: Guohua
authors.initials: G
authors.lastname: Zeng
authors.forename: Zhenhua
authors.initials: Z
authors.lastname: Zhao
authors.forename: Shawpong
authors.initials: S
authors.lastname: Wan
authors.forename: Sanjay
authors.initials: S
authors.lastname: Khadgi
authors.forename: Yongfu
authors.initials: Y
authors.lastname: Long
authors.forename: Yonghai
authors.initials: Y
authors.lastname: Zhang
authors.forename: Guocan
authors.initials: G
authors.lastname: Cao
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Yang
mesh_terms: D000328:Adult; D000368:Aged; D004621:Embolization, Therapeutic; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009403:Nephrostomy, Percutaneous / Q000009:adverse effects*; D019106:Postoperative Hemorrhage / Q000209:etiology* / Q000628:therapy*; D012077:Renal Artery; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D012720:Severity of Illness Index; D017211:Treatment Failure; D055815:Young Adult
keywords: IAVF; PA; PCNL; PVA; SRAE; embolization; hemorrhage; iatrogenic arteriovenous fistula; kidney; nephrostomy; percutaneous; percutaneous nephrolithotomy; polyvinyl alcohol; pseudoaneurysm; superselective renal arterial embolization; therapeutic; treatment failure