title: Perirenal Hematoma After Ureteroscopy: A Systematic Review.
abstract: With the broadening indications of ureteroscopy (URS) for complex stones and high-risk patients, more URS is being performed and hence there is an increasing risk of major potentially life-threatening complications. We wanted to define the incidence, predisposing factors, management, and long-term sequelae for post-URS perirenal hematoma (PRH).
  
  
  
  We conducted a systematic review of literature according to Cochrane and preferred reporting items for systematic reviews and meta-analysis guidelines for all studies reporting on post-URS PRH from 1980 to September 2016. A literature search was conducted through PubMed, EMBASE, CINAHL, and Cochrane Library for all English language articles.
  
  
  
  Based on a literature search of 210 articles, seven studies (8929 patients) met the inclusion criteria with an incidence of post-URS PRH reported as 0.45% (40 patients, range: 0.15%-8.9% per study) with a mean age of 53 years and a mean stone size of 1.7 cm. The predisposing factors were moderate-severe hydronephrosis, thin renal cortex, prolonged operative duration, hypertension, and preoperative urinary tract infection (UTI). The management strategy varied from conservative management with blood transfusion and antibiotics (n = 22, 55%) to percutaneous drainage (n = 11, 27.5%). Surgical intervention was needed in seven (17.5%) patients. Two of these were emergency angiography of which one proceeded to open nephrectomy. Open surgery with clot removal was done in three patients, nephrostomy for severe hydronephrosis in one patient, and surgery to correct malpositioned stent in one patient. There was one mortality reported, wherein a patient who had postangiography nephrectomy died of multiple organ failure after the intervention.
  
  
  
  URS related PRH is a rare, but potentially life threatening complication with a small risk of renal loss. Although most cases may be managed conservatively, incidence of PRH can be minimized by control of blood pressure, treatment of preoperative UTI, and reduction in intrarenal pressures and operative time duration.
authors.affiliation: 1 Department of Urology, Royal Hampshire County Hospital , Winchester, United Kingdom .
authors.forename: Lily A
authors.initials: LA
authors.lastname: Whitehurst
authors.affiliation: 2 Department of Urology, University Hospital Southampton NHS Foundation Trust , Southampton, United Kingdom .
authors.forename: Bhaskar K
authors.initials: BK
authors.lastname: Somani
mesh_terms: D000328:Adult; D000368:Aged; D004322:Drainage; D005260:Female; D006406:Hematoma / Q000209:etiology*; D006801:Humans; D006869:Hydronephrosis / Q000150:complications / Q000209:etiology / Q000601:surgery; D015994:Incidence; D007668:Kidney; D007669:Kidney Calculi / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D009392:Nephrectomy / Q000379:methods; D000074643:Nephrotomy / Q000379:methods; D061646:Operative Time; D015607:Stents; D016896:Treatment Outcome; D018666:Ureteroscopy / Q000009:adverse effects*; D014552:Urinary Tract Infections / Q000150:complications / Q000209:etiology
keywords: complication; hemorrhage; perirenal hematoma; renal; ureteroscopy