Tempering Expectations for Outpatient Total Knee Arthroplasty for Patients Over 70

Total knee arthroplasty (TKA) is now considered an outpatient procedure, yet advanced age impacts patients’ ability to achieve outpatient discharge. Therefore, the purpose of this study is to determine the rate of successful outpatient discharge for TKA patients above 70 years of age and identify potential barriers to success.

This retrospective review included 352 unilateral TKA patients. The rapid discharge protocol was followed for all patients with the intention of discharge within a 24-hour period. Successful outpatient discharge was classified as ≤24-hour stay and failure was any stay exceeding a 24-hour period in the hospital. Univariate logistic regressions were performed to determine the influence of independent variables on discharge status for all patients and only patients >70 years old.

Overall, 46 patients (13%) failed to achieve outpatient discharge, with 35 (76%) patients being ≥70 years old. For patients ≥70, age was not a predictive variable for failure to achieve outpatient discharge (P = .484). However, being female (odds ratio 3.273, 95% confidence interval 1.286-8.325, P = .013) and the use of an assistive walking device (odds ratio 3.031, 95% confidence interval 1.387-6.625, P = .005) remained independent contributors to prolonged hospital stay.

With patients ≥70 years old more likely to require >24-hour stays, age should be an evaluated metric for justifying higher levels of reimbursement. Although TKA is now considered an outpatient procedure, greater consideration should be given to patients ≥70 years old for higher levels of reimbursement as outpatient discharge is less likely to be successful.