Is Outpatient Arthroplasty as Safe as Fast-Track Inpatient Arthroplasty? A Propensity Score Matched Analysis

In the emerging fiscal climate of value-based decision-making and shared risk and remuneration, outpatient total joint arthroplasty is attractive provided the incidence of costly complications is comparable to contemporary "fast-track" inpatient pathways.

All patients undergoing total hip arthroplasty or total knee arthroplasty between 2011 and 2013 were selected from the American College of Surgeons-National Surgical Quality Improvement Program database. A propensity score was used to match 1476 fast-track (≤2 day length of stay) inpatients with 492 outpatients (3:1 ratio). Thirty-day complication, reoperation, and readmission rates were compared, both during and after hospitalization. Logistic regression was used to calculate propensity score adjusted odds ratios.

After matching, outpatients had higher rates of medical complication (anytime, 10.0% vs 6.7%, P = .018; post discharge, 6.3% vs 1.1%, P < .001). Most complications were bleeding requiring transfusion, which occurred at similar rates after surgery but at higher rates post discharge in outpatients (anytime, 7.5% outpatients vs 5.6% inpatients, P = .113; post discharge, 4.1% outpatients vs 0.1% inpatients, P < .001). There was no difference in readmission rate (2.4% outpatient vs 2.0% inpatient, P = .589).

Outpatients experience higher rates of post-discharge complications, which may countermand cost savings. Surgeons wishing to implement outpatient total joint arthroplasty clinical pathways must focus on preventing post-discharge medical complications to include blood management strategies.