Is Outpatient Total Hip Arthroplasty Safe?

Background: Safety data for outpatient total hip arthroplasty (THA) remains scarce.

Methods: The present study retrospectively reviews prospectively collected data from the 2005-2014 American College of Surgeons National Surgical Quality Improvement Program Database. Patients who underwent THA were categorized by day of hospital discharge to be outpatient (length of stay [LOS] 0 days) or inpatient (LOS 1-5 days). Those with extended LOS beyond 5 days were excluded. To account for baseline nonrandom assignment between the study groups, propensity score matching was used. The propensity matched populations were then compared with multivariate Poisson regression to compare the relative risks of adverse events during the initial 30 postoperative days including readmission.

Results: A total of 63,844 THA patients were identified. Of these, 420 (0.66%) were performed as outpatients and 63,424 (99.34%) had LOS 1-5 days. Outpatients tended to be younger, male, and to have fewer comorbidities. After propensity score matching, outpatients had no difference in any of 18 adverse events evaluated other than blood transfusion, which was less for outpatients than those with a LOS of 1-5 days (3.69% vs 9.06%, P < .001).

Conclusion: After adjusting for potential confounders using propensity score matching and multivariate logistic regression, patients undergoing outpatient THA were not at greater risk of 30 days adverse events or readmission than those that were performed as inpatient procedures. Based on the general health outcome measures assessed, this data supports the notion that outpatient THA can appropriately be considered in appropriately selected patients.