Underestimation of Unplanned Readmission after Colorectal Surgery: A National Analysis

Background: A significant proportion of postoperative readmission occurs at a different hospital and is therefore missed by current benchmarking. There are no national studies tracking readmission at different hospitals after colorectal surgery. This study aimed to determine the national burden of postoperative colorectal readmission, including readmission to a different hospital. Study Design: The 2013 to 2014 Nationwide Readmissions Database was queried for adults undergoing colorectal surgery. The outcome of interest was 30-day unplanned readmission. Risk factors were identified. Results: There were 79,098 patients admitted during the study period, with 7.1% (n = 5,591) readmitted and of those, 10.2% (n = 569) readmitted to a different hospital. Risk factors for readmission to a different hospital included admission to a high-volume hospital (odds ratio [OR] 1.49 [95% CI 1.17 to 1.91], p < 0.01), teaching hospital (OR 1.26 [95% CI 1.01 to 1.59], p = 0.04), nonmetropolitan hospital (OR 2.75 [95% CI 1.95 to 3.89], p < 0.01), hospitalization more than 7 days (OR 1.67 [95% CI 1.33 to 2.10], p < 0.01), and elective admission (OR 1.57 [95% CI 1.22 to 2.02], p < 0.01). Predictors of readmission to a different hospital were different than predictors of readmission. The most common reason for readmission was infection (28.4%). Conclusions: The burden of readmission to a different hospital after colorectal surgery is significant and disproportionately affects high-volume hospitals. Current quality metrics underestimate readmission, failing to capture the subpopulation readmitted to a different hospital. Interventions designed to prevent readmission need to be tailored to the unique risk factors described for different hospital readmission. Benchmarking not measuring different hospital readmission is inaccurate and should be modified.