OBJECTIVES: To compare hospital resource utilization between elective and emergent admissions among patients undergoing inpatient colorectal surgery.

METHODS: This retrospective, observational study used hospital billing data from >600 hospitals in the U.S. (Premier Healthcare Database). Patients included were admitted for inpatient colorectal surgery between 1/1/2008-12/31/2014 (first observed admission=index) and were aged ≥18 years as of index. Patients were classified as having either an elective or emergent (admitted through the emergency room) admission. Study outcomes included total hospital costs (HC), length of stay (LOS), and operating room time (ORT). Outcomes were compared between elective and emergent admissions using multivariable Generalized Estimating Equations (GEE) models, which adjusted for patient, procedure, and hospital factors, and accounted for potential within-hospital clustering. Adjusted predicted outcomes were generated for each group using the least squares means method.

RESULTS: Of the 227,632 patients with colorectal surgery (average age=63.3 years; 53.2% female), 94,902 (41.7%) had emergent admissions. Compared to elective admissions, emergent admissions had a higher proportion of patients with open surgeries (78.2% vs 49.5%), and lower proportions of surgeries with colon/rectal specialty surgeons (9.6% vs 21.3%) or with diagnoses of colorectal cancer (28.7% vs 43.5%). In the GEE models, HC was 50.8% (95% CI: 48.1%-53.6%, p<0.0001) higher in emergent versus elective admissions (adjusted HC=$28,966 emergent, $19,209 elective); LOS was 61.1% (58.0%-64.2%, p<0.0001) higher in emergent versus elective admissions (adjusted LOS=11.2 days emergent, 6.9 days elective); and ORT was 6.3% (5.5%-7.2%, p<0.0001) shorter in emergent versus elective admissions (adjusted ORT=187.0 minutes elective, 199.6 minutes emergent).

CONCLUSIONS: Among patients undergoing inpatient colorectal surgery, substantial differences were identified between elective and emergent admissions in terms of surgical approach, surgeon specialty, indication, and hospital resource utilization among patients with inpatient colorectal surgeries. Emergent admissions are complex in nature; further research is warranted to understand drivers of the observed outcome differences.