Outpatient total shoulder arthroplasty: a population-based study comparing adverse event and readmission rates to inpatient total shoulder arthroplasty.

BACKGROUND The rate of total shoulder arthroplasty (TSA) is rising, which has an impact on health care expenditure. One avenue to mitigate cost is outpatient TSA. There are currently no published reports of this practice. In this study, we determine the 30-day adverse event and readmission rates after outpatient TSA and compare these rates with inpatient TSA. METHODS A retrospective cohort study using a population database in the United States was undertaken. Patients who underwent primary TSA between 2005 and 2014 were identified and divided into 2 cohorts based on length of stay (LOS): outpatient TSA (LOS 0 days) and inpatient TSA (LOS >0 days). Patient and procedure characteristics were collected. The 30-day adverse event and readmission rates were calculated for each cohort. A multivariate logistic regression determined if the odds of an adverse event or readmission were significantly different between the inpatient and outpatient TSA cohorts. RESULTS Overall, 7197 patients in this database underwent TSA between 2005 and 2014, of which 173 patients (2.4%) underwent outpatient TSA. The 30-day adverse event rate in the outpatient and inpatient TSA cohorts was 2.31% and 7.89%, respectively. The 30-day readmission rate in the outpatient and inpatient TSA cohorts was 1.74% and 2.93%, respectively. In the multivariate logistic regression, the odds of an adverse event or readmission were not significantly different (odds ratio of 0.4 [P = .077] and odds ratio of 0.7 [P = .623], respectively). CONCLUSION There are no significant differences in the 30-day adverse event and readmission rates between outpatient and inpatient TSA. In the appropriately selected patient, outpatient TSA is safe and cost-effective.