OBJECTIVES: This is an exploratory analysis of potential variables associated with roux-en-Y gastric bypass (RYGB) surgery hospitalization resource use pattern. METHODS: Cross-sectional study based on a public database (DATASUS) records. Inclusion criteria were patients undergoing RYGB between January 2008 and June 2011. Dependent variables were length of stay and ICU need. Independent variables were:  gender, age at surgery (continuous or categorized as older/younger than 60), hospital volume (high volume: >100 RYGB/year; low volume: ≤100 RYGB/year), surgery at certified center of excellence (CoE) by the American Society for Metabolic and Bariatric Surgery (ASMBS) (yes/no), year of hospitalization. Univariate and multivariate analysis (logistic regression for ICU need and linear regression for length of stay) were performed. RESULTS: Data from 13,069 surgeries were analyzed. 14.8% of patients were male, mean age 38.2±10.4 years, 52.2% undergone surgery in a high volume hospital, 11.6% from a certified CoE by ASMBS. In the univariate analysis of potential factors associated with outcomes of interest, the variable with highest effect size for length of stay was hospital volume (high volume 3.8±1.8 days vs 6.3±7.6 low volume, p<0.001), whereas for ICU need it was certified CoE (50.0% vs. 1.3%, p<0.001). Final model for ICU need after logistic regression includes certified CoE (OR 0.009, CI95% 0.006-0.014), hospital volume (OR 3.16, CI95% 2.93-3.41) and age group (OR 1.93, CI95% 1.46-2.57). The most important variable in the final model for log-transformed length of stay is hospital volume (adjusted coefficient -0.338, CI95% -0.379 to -0.297); association was also found for certified CoE, gender and age. In high volume hospitals, variance of RYGB length of stay is significantly lower than variance in low volume hospitals (SD 2.1 vs. 11.0, p<0.001). CONCLUSIONS: High volume hospitals are strongly associated with shorter length of stay and less variability, and ASMBS certification is strongly associated with less need for ICU.