The effect of regionalization on outcome in esophagectomy: a Canadian national study.

BACKGROUND

Regionalization of specialized surgical services has been proposed to improve outcomes based on the reported association between volume and outcomes. The effect of regionalization of esophagectomy on in-hospital mortality (IHM) and length of stay (LOS) was examined.

METHODS

Data from a Canadian database for 6985 patients (74% men; median age, 66 years) who underwent esophagectomy (1998 to 2007) were analyzed with a multivariable mixed model regression controlling for age, sex, Charlson comorbidity index, and year of esophagectomy to evaluate the effect of hospital volume. Volume changes were evaluated within and between hospitals.

RESULTS

From 1998 to 2007, the number of hospitals performing esophagectomies decreased (101 to 85). The percentage of patients treated in large-volume (>20 cases/year) centers increased (29% to 61%) and IHM decreased (9.1% to 3.6%). The odds of IHM decreased 64% (95% confidence interval [CI], 51% to 74%), and LOS decreased 38% (95% CI, 34% to 43%). Comparing between hospitals, an increase of 10 cases was associated with a 15% decrease in IHM (95% CI, 6% to 23%, p=0.001) and a 10% increase in LOS (95% CI, 2% to 19%, p=0.01). Within an individual hospital, the relationship between increasing volume and LOS or IHM was not significant.

CONCLUSIONS

In-hospital mortality for esophagectomy has decreased in Canada but was not significantly reduced when volume was increased within a given hospital. Improved IHM may be related to selective referral of patients to high-volume hospitals. Although, decreased IHM is not solely attributable to volume changes, our results support regionalization policies for esophagectomy.