title: Factors influencing the volume-outcome relationship in gastrectomies: a population-based study.
abstract: BACKGROUND
  A relationship between hospital procedural volume and patient outcomes has been observed in gastrectomies for primary gastric cancer, but modifiable factors influencing this relationship are not well elaborated.
  
  
  METHODS
  We performed a population-based study of 1864 patients undergoing gastrectomy for primary gastric cancers at 214 hospitals. Hospitals were stratified as high-, intermediate-, or low-volume centers. Multivariate models were constructed to evaluate the effect of institutional procedural volume and other hospital- and patient-specific factors on the risk of in-hospital mortality, adverse events, and failure to rescue, defined as mortality after an adverse event.
  
  
  RESULTS
  High-volume centers attained an in-hospital mortality rate of 1.0% and failure-to-rescue rate of .7%, both less than one-fifth of that seen at intermediate- and low-volume centers, although adverse event rates were similar across the three volume tiers. In multivariate modeling, treatment at a high-volume hospital decreased the odds of mortality (odds ratio [OR], .22; 95% confidence interval [95% CI], .05-.89), whereas treatment at an institution with a high ratio of licensed vocational nurses per bed increased the odds of mortality (OR, 1.96; 95% CI, 1.04-3.75). Being treated at a hospital with a greater than median number of critical care beds decreased odds of mortality (OR, .46; 95% CI, .25-.81) and failure to rescue (OR, .53; 95% CI, .29-.97).
  
  
  CONCLUSIONS
  Undergoing gastrectomy at a high-volume center is associated with lower in-hospital mortality. However, improving the rates of mortality after adverse events and reevaluating nurse staffing ratios may provide avenues by which lower-volume centers can improve mortality rates.
authors.affiliation: Department of Surgery, Wilford Hall Medical Center, 2200 Bergquist Drive/Ste 1, Lackland AFB, Texas 78236, USA.
authors.forename: David L
authors.initials: DL
authors.lastname: Smith
authors.forename: Linda S
authors.initials: LS
authors.lastname: Elting
authors.forename: Peter A
authors.initials: PA
authors.lastname: Learn
authors.forename: Chandrajit P
authors.initials: CP
authors.lastname: Raut
authors.forename: Paul F
authors.initials: PF
authors.lastname: Mansfield
mesh_terms: D000368:Aged; D015331:Cohort Studies; D003422:Critical Care / Q000706:statistics & numerical data; D005260:Female; D005743:Gastrectomy / Q000009:adverse effects / Q000706:statistics & numerical data*; D005763:Gastroenterostomy / Q000009:adverse effects / Q000706:statistics & numerical data; D017052:Hospital Mortality; D006761:Hospitals / Q000145:classification*; D006784:Hospitals, Teaching / Q000706:statistics & numerical data; D006786:Hospitals, Urban / Q000706:statistics & numerical data; D006801:Humans; D008197:Lymph Node Excision / Q000009:adverse effects / Q000706:statistics & numerical data; D008297:Male; D009726:Nurses / Q000706:statistics & numerical data; D009741:Nursing Staff, Hospital / Q000706:statistics & numerical data; D011159:Population Surveillance; D011183:Postoperative Complications / Q000453:epidemiology; D012307:Risk Factors; D013156:Splenectomy / Q000009:adverse effects / Q000706:statistics & numerical data; D013274:Stomach Neoplasms / Q000601:surgery*; D013781:Texas / Q000453:epidemiology; D016896:Treatment Outcome