Comparing outcomes in revision total hip arthroplasty in inpatient versus outpatient setting: a matched cohort analysis.

Abstract

As the population ages, revision total hip arthroplasty (rTHA) is becoming more common. However, there is a paucity of literature regarding perioperative outcomes following inpatient versus outpatient rTHA. Our study aims to compare perioperative complications and readmission rates associated with rTHA in a large national cohort. A retrospective, propensity-matched cohort study was conducted using the National Surgical Quality Improvement Program database from 2006 to 2020. Patients undergoing rTHA in the inpatient setting were propensity matched to patients receiving rTHA in the outpatient setting. Following 1:1 matching, multivariate analyses were performed to compare perioperative complications and readmission. A total of 207,102 patients were identified, including 181,164 outpatient primary THA, 25,466 inpatient rTHA, and 492 outpatient rTHA patients. Following propensity matching, outpatient primary THA versus outpatient rTHA had 210 patients and inpatient rTHA versus outpatient rTHA had 214 patients. Patients in the outpatient rTHA had a significantly higher operative time (132.4 ± 73.2 versus 90.9 ± 32.7, p < 0.001) and length of stay (1.6 ± 1.6 vs. 0.9 ± 1.0, p < 0.001) compared to outpatient primary THA. When comparing inpatient versus outpatient rTHA, the outpatient cohort had lower operative time (131.1 ± 70.9 vs. 145.4 ± 71.5, p = 0.038), total length of stay (1.7 ± 1.8 vs. 3.6 ± 4.1, p < 0.001), and bleeding complications (6% vs. 18%, p < 0.001). There were no difference in the odds of complications between outpatient primary and revision THA. Additionally, rTHA performed in an outpatient setting did not show any increase in immediate compared to inpatient settings. These findings suggest that rTHA can be safely performed on certain patients.