Hospital readmission rates following outpatient versus inpatient shoulder arthroplasty

Outpatient total shoulder arthroplasty (TSA) is an alternative to surgery with inpatient admission for appropriate patients. Controlled studies assessing differences in perioperative outcomes between inpatient and outpatient TSA are lacking. In this study, the primary outcome was 30-day all-cause hospital readmission following inpatient vs outpatient TSA. The National Surgical Quality Improvement Program (NSQIP) database was used to identify patients undergoing both primary and revision TSA from 2010 to 2017. Patients were identified using Current Procedural Terminology codes. A 1:1 propensity score matching was used to create two groups of patients, those who underwent outpatient surgery and those who underwent inpatient surgery, while matching for age, sex, American Society of Anesthesiologists classification, primary vs revision surgery, smoking, diabetes, chronic obstructive pulmonary disease, and congestive heart failure. This study had a power of 85% to detect a difference of 1% in 30-day readmission. Following 1:1 propensity score matching, 1714 patients who underwent inpatient TSA and 1714 patients who underwent outpatient TSA were analyzed. All-cause 30-day readmission rates were 3.4% in the outpatient group and 1.7% in the inpatient group (P<.01). A total of 1.9% of patients who underwent outpatient surgery had a 30-day readmission for a surgical complication compared with 1.4% of patients who underwent inpatient surgery (P=.32). Although patients who underwent outpatient TSA had an increased risk of all-cause 30-day readmission compared with equally matched controls who underwent inpatient TSA, readmission for surgical complications was equivalent between the two groups. Careful patient selection for outpatient TSA should be emphasized to minimize the potential for postoperative hospital admission.