Comparison of Patients Based on Their Self-Selected Discharge Pathway after Total Knee Arthroplasty at an Ambulatory Surgical Center

Outpatient total knee arthroplasty (TKA) is being performed more frequently in ambulatory surgical centers (ASCs) to decrease the cost of care. Discharge pathways include 23-hour observation (OBSERVATION) or same-day discharge home (HOME), which differ in postoperative medical supervision. Few studies allow patients to self-select their discharge pathway. This study compared patient variables between self-selected OBSERVATION or HOME discharge after TKA at an ASC. We hypothesized that age, sex, and distance lived from the ASC would differ between discharge pathways. Clinical and patient-reported outcomes were explored.A chart review identified 130 patients with TKA at an ASC between November 2017 and December 2019. Patients self-selected OBSERVATION or HOME during a preoperative physician visit. Patient variables obtained from the electronic medical record were age, sex, race/ethnicity, marital status, body mass index, diabetic status, American Society of Anesthesiologists (ASA) class, distance lived from the ASC, anesthesia type, procedure time, and time in the postanesthesia recovery unit. Clinical outcomes (knee range of motion, infection rate, and reoperation rate) and patient-reported outcomes (Knee Injury and Osteoarthritis Outcome Score, Joint Replacement [KOOS, JR]; Oxford Knee Score [OKS]) were collected at either 6 or 12 weeks postsurgery. Variables were compared between groups.Pathway selection was n = 70 OBSERVATION and n = 60 HOME, and all patients completed their self-selected discharge pathway. Age and proportion of females were significantly higher in OBSERVATION than in HOME (61.3 ± 3.5 vs. 58.5 ± 5.4 years, 85.7 vs. 65.0%, respectively; p < 0.05). Distance lived from the ASC tended to be greater in OBSERVATION than HOME (22.1 ± 24.6 vs. 15.3 ± 10.1 miles, p = 0.056). Across groups, clinical outcomes were favorable (i.e., >88% met the 6-week knee flexion milestone, 1.9% infection rate, and 3.1% manipulation under anesthesia), and the preoperative to 12-week postoperative change in KOOS, JR and OKS scores met the minimal clinically important difference.Older age, female sex, and farther distance lived from the ASC may influence patients to select OBSERVATION over HOME discharge following TKA at an ASC. No robust differences were found in early outcomes.