title: Radical nephrectomy surgical outcomes in the University HealthSystem Consortium Data Base: Impact of hospital case volume, hospital size, and geographic location on 40,000 patients.
abstract: BACKGROUND
  We sought to determine the impact of radical nephrectomy case volume, hospital size, and geographic region on immediate surgical outcomes for patients undergoing radical nephrectomy in academic centers across the country.
  
  
  METHODS
  The University HealthSystem Consortium (UHC) Clinical Data Base was queried for data corresponding to patients who underwent radical nephrectomy at 1 of 134 academic medical centers nationwide between 2003 and quarter 2 of 2007 (n = 42,988). Radical nephrectomy case volume (1-99, 100-499, and 500 +), total discharges (1-49,999, 50,000-99,999, 100,000 +), and geographic region (5 categories) were determined for each academic center. ANOVA and the Tukey statistic were used. Length of stay, intensive care unit (ICU) rate, complication (comp) rate, and in-hospital mortality were analyzed.
  
  
  RESULTS
  Case volume was a significant predictor of length of stay, ICU, and comp. Mean length of stay was 6.88, 5.61, and 4.76 days, respectively, for centers from lowest to highest case volumes (P < .001). ICU rates for the 3 tiers were 30.77, 17.93, and 12.22 (P < .001). Comp rates were 24.50, 19.40, and 15.48 (P < .001). Tukey analysis revealed a ceiling effect: No differences were seen between the 2 higher case volume groups. Stratification by total discharges revealed differences in ICU rates (P = .001) and comp rates (P = .001). Region of the country had no significant impact on any of the outcome variables in this study.
  
  
  CONCLUSIONS
  Radical nephrectomy case volume emerged as an important variable in predicting 3 of the 4 outcome parameters in this study. Results suggest that a "critical volume" of cases portends improved surgical outcomes.
authors.affiliation: Department of Urologic Surgery, Vanderbilt University, Nashville, Tennessee 37232, USA. robert.mitchell@vanderbilt.edu
authors.forename: Robert E
authors.initials: RE
authors.lastname: Mitchell
authors.forename: Byron T
authors.initials: BT
authors.lastname: Lee
authors.forename: Michael S
authors.initials: MS
authors.lastname: Cookson
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Barocas
authors.forename: S
authors.initials: S
authors.lastname: Duke Herrell
authors.forename: Peter E
authors.initials: PE
authors.lastname: Clark
authors.forename: Joseph A
authors.initials: JA
authors.lastname: Smith
authors.forename: Sam S
authors.initials: SS
authors.lastname: Chang
mesh_terms: D016208:Databases, Factual; D006276:Health Facility Size; D017052:Hospital Mortality; D006801:Humans; D007362:Intensive Care Units; D007680:Kidney Neoplasms / Q000601:surgery; D007902:Length of Stay; D009392:Nephrectomy / Q000401:mortality / Q000706:statistics & numerical data*; D017063:Outcome Assessment, Health Care; D013503:Surgery Department, Hospital / Q000706:statistics & numerical data*; D016896:Treatment Outcome; D014481:United States