title: Patient selection and the volume effect in pancreatic surgery: unequal benefits?
abstract: BACKGROUND
  The volume effect in pancreatic surgery is well established. Regionalization to high-volume centres has been proposed. The effect of this proposal on practice patterns is unknown.
  
  
  METHODS
  Retrospective review of pancreatectomy patients in the Nationwide Inpatient Sample 2004-2011. Inpatient mortality and complication rates were calculated. Patients were stratified by annual centre pancreatic resection volume (low <5, medium 5-18, high >18). Multivariable regression model evaluated predictors of resection at a high-volume centre.
  
  
  RESULTS
  In total, 129,609 patients underwent a pancreatectomy. The crude inpatient mortality rate was 4.3%. 36.0% experienced complications. 66.5% underwent a resection at high-volume centres. In 2004, low-, medium- and high-volume centres resected 16.3%, 24.5% and 59.2% of patients, compared with 7.6%, 19.3% and 73.1% in 2011. High-volume centres had lower mortality (P < 0.001), fewer complications (P < 0.001) and a shorter median length of stay (P < 0.001). Patients at non-high-volume centres had more comorbidities (P = 0.001), lower rates of private insurance (P < 0.001) and more non-elective admissions (P < 0.001).
  
  
  CONCLUSIONS
  In spite of a shift to high-volume hospitals, a substantial cohort still receives a resection outside of these centres. Patients receiving non-high-volume care demonstrate less favourable comorbidities, insurance and urgency of operation. The implications are twofold: already disadvantaged patients may not benefit from the high-volume effect; and patients predisposed to do well may contribute to observed superior outcomes at high-volume centres.
authors.affiliation: Surgical Outcomes Analysis & Research and Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA; Department of Surgery, University of Connecticut Health Center, University of Connecticut School of Medicine, Farmington, CT, USA.
authors.forename: Lindsay A
authors.initials: LA
authors.lastname: Bliss
authors.forename: Catherine J
authors.initials: CJ
authors.lastname: Yang
authors.forename: Zeling
authors.initials: Z
authors.lastname: Chau
authors.forename: Sing Chau
authors.initials: SC
authors.lastname: Ng
authors.forename: David W
authors.initials: DW
authors.lastname: McFadden
authors.forename: Tara S
authors.initials: TS
authors.lastname: Kent
authors.forename: A James
authors.initials: AJ
authors.lastname: Moser
authors.forename: Mark P
authors.initials: MP
authors.lastname: Callery
authors.forename: Jennifer F
authors.initials: JF
authors.lastname: Tseng
mesh_terms: D000368:Aged; D015897:Comorbidity; D017558:Elective Surgical Procedures; D004630:Emergencies; D005260:Female; D054625:Healthcare Disparities; D017052:Hospital Mortality; D061847:Hospitals, High-Volume; D061846:Hospitals, Low-Volume; D006801:Humans; D007348:Insurance, Health; D007902:Length of Stay; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D010043:Outcome and Process Assessment, Health Care; D010180:Pancreatectomy / Q000009:adverse effects / Q000401:mortality; D018579:Patient Selection; D011183:Postoperative Complications / Q000401:mortality; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome; D014481:United States