Outcomes of Same-Day Discharge After Total Hip Arthroplasty in the Medicare Population

The Journal of Arthroplasty xxx (2019) 1e5

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Outcomes of Same-Day Discharge After Total Hip Arthroplasty in the Medicare Population Oren I. Feder, MD, Katherine Lygrisse, Lorraine Hultzer, MPA, Ran Schwarzkopf, MD, Joseph Bosco, MD, Roy I. Davidovitch, MD * Department of Orthopedic Surgery, NYU Langone Health, NYU Langone Orthopedic Hospital, New York, NY

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Article history: Received 5 August 2019 Received in revised form 15 September 2019 Accepted 26 September 2019 Available online xxx

Background: There is an increasing utilization of same-day discharge total hip arthroplasty (SDD THA). As the Center for Medicare and Medicaid Services considers removing THA from the inpatient-only list, there is likely to be a significant increase in the number of Medicare patients undergoing SDD THA. Thus, there is a need to report on outcomes of SDD THA in this population. Methods: A retrospective review was performed on 850 consecutive SDD THA patients including 161 Medicare patients. We compared failure to launch, complication, emergency department visit, and 90day readmission rates between the Medicare and non-Medicare cohorts. Results: The Medicare group was older and had less variability in their admission diagnosis. There was no significant difference in failure to launch, complication, emergency department visit, or 90-day readmission rates between Medicare and non-Medicare groups. Conclusion: The benefits of SDD THA can be safely extended to the carefully indicated and motivated Medicare patient. © 2019 Elsevier Inc. All rights reserved.

Keywords: total hip arthroplasty total hip replacement same-day discharge same-day surgery medicare

Healthcare is evolving toward a value-based model focused on reducing costs while optimizing outcomes. This has led to an increasing interest in same-day discharge total hip arthroplasty (SDD THA). SDD can add value to THA by decreasing costs without compromising outcomes [1,2]. With improvement in surgical technique, blood management, the use of regional anesthesia, and the development of rapid recovery pathways, multiple studies have demonstrated the safety of SDD THA in properly selected patients with outcomes similar to patients undergoing inpatient THA [3e6]. SDD THA results in improved patient satisfaction, decreased perioperative hospital-associated morbidity, and reduced costs and has not shown a concomitant increase in postoperative complications and readmissions [7,8]. As a result of the increasing popularity of

Funding: This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. One or more of the authors of this paper have disclosed potential or pertinent conflicts of interest, which may include receipt of payment, either direct or indirect, institutional support, or association with an entity in the biomedical field which may be perceived to have potential conflict of interest with this work. For full disclosure statements refer to https://doi.org/10.1016/j.arth.2019.09.040. * Reprint requests: Roy I. Davidovitch, MD, Department of Orthopedic Surgery, NYU Langone Orthopedic Hospital, 485 Madison Ave. 8th Floor, New York, NY 10022. https://doi.org/10.1016/j.arth.2019.09.040 0883-5403/© 2019 Elsevier Inc. All rights reserved.

SDD THA, and the reimbursement of both hospitals and ambulatory surgery centers by private insurers for SDD THA, the Center for Medicare and Medicaid Services (CMS) is considering removing THA from the inpatient-only (IPO) list. The projected utilization of THA is expected to increase significantly over the next 2 decades, coincident with a simultaneous increased percentage of the population becoming Medicare eligible [9]. The removal of THA from the IPO list would likely lead to a significant increase in the number of Medicare patients undergoing SDD THA. However, to our knowledge, no studies have specifically looked at the outcomes of SDD THA in Medicare patients as they relate to non-Medicare patients. The objective of this study is to report on the outcomes of SDD THA in Medicare patients as they compare to outcomes of SDD THA in non-Medicare patients. We examined failure to launch (FTL) rates, complications, and readmissions within 90 days in these patients. We hypothesized that Medicare patients can be safely discharged the same day after THA without an increase in FTL, complications, or 90-day readmissions when compared to non-Medicare patients. Methods Before the start of this study, institutional review board approval was obtained. We retrospectively reviewed all consecutive patients

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who enrolled in our institution’s SDD THA program from January 2015 through May 2019. We excluded all patients who withdrew from the SDD program before the day of surgery. Patient charts were reviewed through our institution’s electronic medical record. Demographic and clinical data including age, gender, ethnicity, body mass index (BMI), smoking status, American Society of Anesthesiologists (ASA) class, admission diagnosis, and insurance type were collected. We separated the study group into 2 cohorts based on insurance type. Cohort 1 consisted of Medicare patients and Cohort 2 consisted of non-Medicare patients. We compared outcomes between the 2 cohorts. The institution’s Center for Quality and Patient Safety assisted in data collection and their internal database was queried to extract all quality metrics used for the study including length of stay (LOS), perioperative complications, postoperative emergency department (ED) visits, infections, and 90-day readmissions. We defined FTL as any patient with a LOS of 1 night or more. All surgeries were performed at the hospital and not at an ambulatory surgery setting. SDD Perioperative Management All patients in the SDD cohort underwent a THA at our institution by a single surgeon. Patients qualified for the SDD THA program if they met the following criteria: no history of active coronary artery disease or arrhythmias, not currently on chronic anticoagulation, no history of untreated moderate or severe sleep apnea, hemoglobin > 12 g/dL, and a BMI < 40 kg/m2. Patients were also required to have a personal coach (friend or relative) who would attend the preoperative education session (a one-on-one encounter with a clinical care coordinator and a physical and occupational therapist for 2 hours before the surgical date) and be present on the day of surgery and at their home for the first night after discharge. While the personal coach was encouraged to be with the patient and assist them throughout the full recovery period, there was no requirement that the coach be with the patient after postoperative day 1. During the preoperative education session, the care extenders educated the patient on the expected recovery course, pain management modalities, physical therapy exercises, and postoperative expectations. Patients who no longer desired to take part in the SDD THA or who failed to meet program requirements could withdraw from the program at any time preceding the day of surgery. Before surgery, all patients received authorization from their insurance for an inpatient THA. Patients in both cohorts were admitted under inpatient status on the day of surgery. All patients received preemptive analgesia on the day of surgery consisting of celecoxib, acetaminophen, and long-acting oxycodone. A standardized anesthesia protocol was used for all SDD patients. All patients received a short-acting spinal anesthesia with 0.5% ropivacaine to facilitate immediate postoperative patient mobilization. The specific anesthetic regimen administered during the surgery included fentanyl, propofol, midazolam, and intravenous dexamethasone. A uniform perioperative multimodal pain regimen was established to reduce the need for narcotics. This included the use of a 0.25% bupivacaine with epinephrine and 30 mg ketorolac periarticular cocktail in addition to a liposomal bupivacaine periarticular injection before wound closure. This injection was not used in patients with renal insufficiency or with allergies to the injected medications. Postoperative pain management was accomplished using several non-narcotic medications including oral acetaminophen, as well as celecoxib or meloxicam which were routinely used for pain control. Patientcontrolled analgesia was not used in any patient. Opioid analgesia was available to all patients but was strongly discouraged except when alternatives had been exhausted. Tramadol was the first-line opiate of choice, while oxycodone was offered as an alternative in

patients who were not opiate naïve, or in patients who expressed specific preference for this medication based on their prior experience with pain management after surgical procedures. This pain management regimen was continued upon discharge. The Aldrete’s scoring system was used to assess when patients were ready to be discharged from the recovery unit. After discharge from postanesthesia care unit, patients were transferred to their assigned inpatient bed where they were seen by physical therapists to assist with early ambulation and ensure the patient was safe for discharge to home. Physical therapists used an ambulation distance of 100 ft with minimal assistance and ability to climb stairs as criteria for safe discharge. All patients were prescribed antibiotics to complete 24 hours of perioperative prophylactic coverage. This included oral antibiotics for patients who were discharged home or intravenous antibiotics for patients who remained in the hospital. Additionally, all patients were prescribed thromboprophylactic agents which consisted of either 325 mg PO BID or 81 mg PO BID of aspirin for a period of 4 weeks and mechanical compression devices for a period of 2 weeks. Active smokers were prescribed Lovenox 40 mg daily for 4 weeks instead of aspirin and compression devices as per our institutional protocol. Once they had been deemed medically and functionally safe for discharge, all patients were discharged home. Statistical Analysis All data were organized and collected on Excel software (Microsoft Corporation, Richmond, WA). Baseline and demographic characteristics were summarized by standard descriptive summaries (eg, means and standard deviations for continuous variables such as age and BMI, and percentages for categorical variables such as gender and readmission rates). Categorical baseline characteristics and outcomes were analyzed using a chi-square test with Fischer’s P value reported between the 2 groups. An analysis was performed comparing successful SDD rates in Medicare and nonMedicare patients. The rate of postoperative ED visits and readmissions were compared between these patient cohorts. In all instances, a P value of less than .05 was deemed significant. All statistical analyses were done using SPSS Statistics software (International Business Machines Inc, Armonk, NY). Results Demographics A total of 1040 patients enrolled in our institution’s SDD THA program during the study time period. Before the day of surgery, 190 patients withdrew from the program, leaving 850 patients to be included in our analysis. Of the 190 patients who withdrew from the SDD program, 153 patients were non-Medicare payor status and 37 patients were covered by Medicare. Of the 850 patients included in our analysis, Cohort 1 consisted of 161 Medicare patients and Cohort 2 consisted of 689 nonMedicare patients. The Medicare group contained 19 Medicare advantage patients and 142 Medicare patients. The non-Medicare group consisted of 683 patients with private insurance and 6 Medicaid patients. Baseline characteristics of the cohorts are summarized in Table 1. There were no significant differences in terms of gender with the Medicare cohort consisting of 50% female and 50% male, while the non-Medicare cohort was 51% female and 49% male (P ¼ .799). The Medicare group was older at an average age of 69.7 years compared to 55.9 in the non-Medicare group (P < .001). There was greater variability in the admission diagnosis in non-Medicare patients. In the Medicare cohort, all patients were admitted with a diagnosis of primary osteoarthritis (OA), whereas

O.I. Feder et al. / The Journal of Arthroplasty xxx (2019) 1e5 Table 1 Baseline Characteristics and Clinical Outcomes of the Medicare and Non-Medicare Cohorts. Demographics and Outcomes

Medicare (N ¼ 161)

Non-Medicare (N ¼ 689)

Age (SD) Gender (F:M) BMI (SD) Smoking status Current smoker Never smoker Former smoker ASA III II I Race (%) White African American Asian Other Diagnosis (%) Primary OA Hip dysplasia AVN Post-traumatic OA FTL (%) Major complications LOS > 2 midnights (%) ED visits (%) 90-d Readmissions (%)

69.7 (5.3) 80:81 26.5 (4.0)

55.9 (8.4) 350:349 27.3 (4.5)

c2

P Value

0.064

<.001 .799 .033

4 (2.4) 87 (54) 70 (43.4)

49 (7.1) 461 (66) 179 (26)

4.779

.028

10 (6.2) 141 (87.6) 10 (6.2)

24 (3.5) 546 (79.2) 119 (17.3)

2.529

.112

147 8 1 5

(91) (4.9) (0.6) (3.1)

601 30 13 45

(87) (4.3) (1.9) (6.5)

2.054

.152

161 0 0 0 8 1 0 1 1

(100) (0) (0) (0) (4.9) (0.6) (0) (0.6) (0.6)

659 12 11 7 55 12 6 7 9

(95.6) (1.7) (1.6) (1.0) (7.9) (1.7) (0.8) (1.0) (1.3)

7.267

.007

1.727 1.088 1.412 0.218 0.527

.189 .296 .234 .640 .468

SD, standard deviation; F, female; M, male; BMI, body mass index; ASA, American Society of Anesthesiologists; OA, osteoarthritis; AVN, avascular necrosis; FTL, failure to launch; LOS, length of stay; ED, emergency department.

the non-Medicare group had 12 patients (1.7%) with hip dysplasia, 11 patients (1.6%) with osteonecrosis, and 7 patients (1.0%) with post-traumatic OA as the admission diagnosis (P ¼ .007). There was a statistically significant although clinically insignificant difference in BMI with the Medicare group having an average BMI of 26.4 as opposed to 27.3 in the non-Medicare cohort (P ¼ .017). The Medicare group was 91% Caucasian compared to 87% in the nonMedicare group (P ¼ .152). In the Medicare group, 4 patients (2.4%) were current smokers compared to 49 patients (7.1%) in the non-Medicare group (P ¼ .028). These patients who were active smokers were discharged on Lovenox for deep vein thrombosis prophylaxis, while all other patients received aspirin upon discharge. The percentage of patients who were ASA class 3 was 6.2% in the Medicare group and 3.4% in the non-Medicare group (P ¼ .11).

FTL, Complications, and Readmission Rates Overall, 93% of THA patients enrolled in our SDD program were successfully discharged on the day of surgery. The overall FTL rate in the Medicare group was 4.9%, compared to 7.9% in the nonMedicare group (P ¼ .189). Subgroup analysis demonstrated that among patients receiving Lovenox due to active smoking status, there were no FTLs in the Medicare group and 4 FTLs in the nonMedicare group (P ¼ .419). Among ASA class 3 patients, there were 5 FTLs in the non-Medicare cohort and no FTLs in the Medicare group (P ¼ .118). In the non-Medicare group, there was a 20% FTL rate in patients whose admission diagnosis was not primary OA, compared to a 7.2% FTL rate in patients with OA as their primary diagnosis (P ¼ .012). The primary reasons for patients not being discharged on the day of surgery included poorly controlled pain, nausea or lightheadedness when ambulating with physical therapy, failure to

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void, and greater than average blood loss intraoperatively that required monitoring overnight. A total of 3 patients had urinary retention postoperatively. One patient was discharged with a Foley catheter while the other 2 preferred to stay overnight. These 2 patients were able to void freely by the next day and did not require a catheter for discharge. All Medicare patients who did not leave on the day of surgery were discharged the next day, whereas 6 patients (0.8%) in the non-Medicare group had an extended LOS greater than 2 nights (P ¼ .23). The complication rate in the Medicare group was 0.6% (1 patient) compared to 1.7% (12 patients) in the non-Medicare group (P ¼ .30). The complication in the Medicare group was a periprosthetic femur fracture which required revision. In the nonMedicare group, the complications included 5 periprosthetic joint infections, 3 periprosthetic femur fractures, 2 cases of instability requiring revision, 1 superficial wound dehiscence, and 1 patient who had postoperative pulmonary edema requiring transfer to a medical unit. Three of the complications in the non-Medicare group occurred during the index hospitalization and therefore did not result in readmission. The 90-day readmission rate was 0.6% (1 patient) in the Medicare group and 1.3% (9 patients) in the nonMedicare group (P ¼ .40). An additional 8 patients presented to the ED within 90 days after surgery but were not admitted. This included 1 Medicare patient (0.6%) and 7 non-Medicare patients (1%; P ¼ .64). The Medicare patient had a vasovagal event on postoperative day 1 which responded to intravenous fluids in the ED. The non-Medicare patients were seen in the ED for a diagnosis of urinary tract infection (3 patients), lower extremity swelling in which deep vein thrombosis was ruled out (2 patients), and lightheadedness which responded to intravenous fluid management (2 patients). No complications or readmissions occurred in patients who were discharged on Lovenox or in ASA class 3 patients in either cohort. Discussion Our study found no differences in outcomes between Medicare and non-Medicare patients undergoing SDD THA. The patient selection for, and the safety and efficacy of, SDD THA is the focus of a growing body of research. The value proposition of SDD THA includes reduced costs, reduced perioperative hospital-associated complications, as well as improved patient satisfaction and recovery [10]. Multiple studies have demonstrated the safety of SDD THA in carefully selected patient populations [11]. With increasing utilization and more widespread acceptance of SDD THA, the indications are being expanded to new patient populations that traditionally were thought to require a minimum inpatient stay to aid in recovery and ensure a safe discharge. When only disqualifying medical conditions are considered, nearly two-thirds of all patients undergoing THAs (Medicare and non-Medicare) are candidates for SDD THA [12]. The ability to perform THA on an SDD basis in the Medicare patient population has cost-saving potential as outpatient reimbursement could occur at a reduced rate through the Outpatient Prospective Payment System while extending the benefits of SDD THA to Medicare beneficiaries. While prior studies have looked at outcomes of SDD THA in patients older than 65, there have been limited studies reporting on outcomes in Medicare patients [13,14]. The findings of this study support the hypothesis that SDD THA is safe and effective with few short-term complications in the carefully indicated Medicare patient. Several concerns arise when considering SDD THA, particularly as these procedures move toward ambulatory surgery centers where extended overnight postoperative care may not be available. In spite of patient screening, not all patients enrolled in an SDD program will be ready for discharge on the same day as their

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operation [15]. In our study, all SDD THAs were performed in an inpatient orthopedic hospital, and FTL patients were able to convert seamlessly to an overnight stay in their assigned inpatient room. If SDD THA was performed in an ambulatory setting without the ability to convert to an overnight stay, these patients would have been negatively affected. We therefore caution against SDD THA in stand-alone ambulatory surgery centers without overnight stay capabilities. There are several factors which may lead to a longer than anticipated stay including poor pain control, inability to void, postoperative hypotension, nausea, the patient’s level of comfort with going home, as well as modifiable factors such as the actual timing of surgery during the day [16]. Prior studies have identified cardiopulmonary disease and cirrhosis as major risk factors for complications in the 24 hours after THA and suggested these patients be excluded from same-day programs [17]. Additionally, previous studies have suggested that age and Medicare status both be considered possible exclusion criteria [18,19]. One concern in extending the indications for SDD THA to Medicare patients is that these patients may increase the FTL rate, limiting the potential costsaving benefits of an SDD arthroplasty program. However, in our study, we found no significant differences in FTL rates between the Medicare and non-Medicare cohorts, and the inclusion of Medicare patients in our SDD program did not significantly affect our institution’s overall FTL rate. We found statistically significant variability in the primary diagnosis in the non-Medicare cohort as well as a significantly increased FTL rate in patients whose primary diagnosis was not primary OA. The non-Medicare patients had higher rates of hip dysplasia, osteonecrosis, and post-traumatic arthrosis as their admission diagnosis. In our experience, younger patients undergoing THA often present with advanced deformity and may have had prior surgical interventions about the hip including osteotomies which increase surgical complexity. These factors may lead to prolonged surgical time, greater blood loss, and increased pain postoperatively [20]. We suggest that a higher degree of pathology may be present in the non-Medicare patients undergoing THA and is a contributing cause of increased FTLs in this cohort. While we have not previously used surgical complexity and degree of difficulty as a criteria for inclusion in our SDD THA program, we recommend that future studies elucidate the impact this may have on FTL rates and clinical outcomes. The variability in the use of the term “outpatient” has led to confusion in the literature as several studies have used it to mean discharge on the same day of surgery, whereas CMS defines outpatient procedures as requiring a hospital stay less than 2 midnights [21]. We considered a successful outpatient THA to be one in which the patient left the hospital on the day of surgery and therefore use the term SDD THA. However, we also observed that all Medicare patients in our cohort who were unable to be discharged on the day of surgery were able to be successfully discharged on postoperative day 1 which CMS would still define as an outpatient stay. In contrast, 5 patients (0.7%) in the non-Medicare group had an extended LOS greater than 2 nights. Thus, we concluded that appropriately selected Medicare patients are not at increased risk of conversion to inpatient based on CMS definitions. Of note, we had no major complications during the index procedure or hospitalization in our Medicare cohort and were therefore unable to elucidate how acute medical and surgical complications impact LOS in Medicare patients if and when they occur. An additional consideration in expanding SDD THA to Medicare patients is the possibility of an increase in complications and 90day readmission rates that may negatively impact patient outcomes and negate the cost-saving benefit, especially given the lower financial margins in these patients. In these patients, a high

readmission rate or a high rate of need for revision THA within 90 days would make performing even primary THA cost-prohibitive [22]. This is particularly concerning as Medicare payor status has been suggested as a risk factor for readmission after THA [18,19]. However, in our study, Medicare patients who were selected for SDD THA demonstrated no increase in acute complication, ED visit, and 90-day readmission rates than the non-Medicare cohort. While the findings of this study suggest the safety of SDD THA in Medicare beneficiaries, it is important to note that the patients included in this cohort were carefully selected and deemed appropriate SDD candidates. Greenky et al [8] found that only 1% of Medicare-age patients (65 or older) who underwent THA were discharged on the same day as surgery. The patients in our cohort do not represent the majority of Medicare patients, but rather are the small subset of healthy, motivated patients with a strong support system enabling a safe, rapid discharge. Age has been implicated previously as a risk factor for perioperative complications, but recent work by Edwards et al [23] found that even carefully selected patients >80 years of age can be included in rapid recovery pathways which reduce the hospital LOS. Our experience and the findings of this study have allowed us to expand our indications for SDD THA to an increasing number of patients. In our institution, we do not limit SDD THA to patients based on age or insurance status but rather use validated screening tools and shared decisionmaking when indicating patients and have found success with this methodology [24]. We suggest that certain healthy, motivated Medicare patients are candidates for SDD THA, but that the decision to proceed with outpatient THA be based on each patient’s unique clinical picture. There are several limitations to the present study. First, the retrospective nature of the study over several years subjects it to the bias of evolving institutional and office-based protocols that might make it difficult to draw comparisons between patients from different periods of the study. Another limitation includes the small sample size of perioperative adverse events and readmissions which may make it underpowered to assess statistically significant differences between groups. Third, our institution is a high-volume orthopedic hospital, and the protocols were implemented in collaboration with our anesthesiologists’ extensive experience in total joint arthroplasty. While our anesthesia department was comfortable performing SDD THA in the patients in this study, these results may not be generalizable to lower-volume centers. For example, ASA III was not used as an exclusion criteria in our study, whereas other institutions may not perform SDD THA in this patient population. Fourth, we only had access to our institution’s medical records, and therefore ED visits not in our healthcare system which did not result in admission may not have been included in our analysis. Our clinical follow-up rate was 100% and therefore all readmissions and complications, whether in our healthcare system or not, were known and included in the analysis. In conclusion, our study found no increase in FTL rates, complications, ED visits, or readmission rates in Medicare patients enrolled in our institution’s SDD program. This study suggests that THA can be safely performed as an SDD procedure in appropriately selected Medicare patients. However, we note that a majority of Medicare patients will continue to require inpatient hospitalization during their immediate recovery after THA. The ultimate decision to schedule THA as an SDD procedure in all patients, including Medicare beneficiaries, should continue to be at the surgeon’s discretion driven by each patient’s clinical and social situation. References [1] Bertin KC. Minimally invasive outpatient total hip arthroplasty: a financial analysis. Clin Orthop Relat Res 2005:154e63.

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[13] Klingenstein GG, Schoifet SD, Jain RK, Reid JJ, Porat MD, Otegbeye MK. Rapid discharge to home after total knee arthroplasty is safe in eligible Medicare patients. J Arthroplasty 2017;32:3308e13. [14] Gronbeck CJ, Cote MP, Halawi MJ. Predicting inpatient status after total hip arthroplasty in medicare-aged patients. J Arthroplasty 2019;34:249e54. [15] Meneghini RM, Ziemba-Davis M, Ishmael MK, Kuzma AL, Caccavallo P. Safe selection of outpatient joint arthroplasty patients with medical risk stratification: the “Outpatient Arthroplasty Risk Assessment Score”. J Arthroplasty 2017;32:2325e31. [16] Courtney PM, Rozell JC, Melnic CM, Lee GC. Who should not undergo short stay hip and knee arthroplasty? Risk factors associated with major medical complications following primary total joint arthroplasty. J Arthroplasty 2015;30(9 Suppl):1e4. [17] Vorhies JS, Wang Y, Herndon JH, Maloney WJ, Huddleston JI. Decreased length of stay after TKA is not associated with increased readmission rates in a national Medicare sample. Clin Orthop Relat Res 2012;470:166e71. [18] Keeney JA, Nam D, Johnson SR, Nunley RM, Clohisy JC, Barrack RL. Socioeconomically disadvantaged CMS beneficiaries do not benefit from the readmission reduction initiatives. J Arthroplasty 2015;30:2082e5. [19] Lavernia CJ, Villa JM, Iacobelli DA. Readmission rates in the state of Florida: a reflection of quality? Clin Orthop Relat Res 2013;471:3856e62. [20] Polkowski GG, Callaghan JJ, Mont MA, Clohisy JC. Total hip arthroplasty in the very young patient. J Am Acad Orthop Surg 2012;20:487e97. [21] Bovonratwet P, Webb ML, Ondeck NT, Lukasiewicz AM, Cui JJ, McLynn RP, et al. Definitional differences of 'outpatient' versus 'inpatient' THA and TKA can affect study outcomes. Clin Orthop Relat Res 2017;475:2917e25. [22] Bosco 3rd JA, Karkenny AJ, Hutzler LH, Slover JD, Iorio R. Cost burden of 30day readmissions following Medicare total hip and knee arthroplasty. J Arthroplasty 2014;29:903e5. [23] Edwards PK, Kee JR, Mears SC, Barnes CL. Is rapid recovery hip and knee replacement possible and safe in the octogenarian patient? J Arthroplasty 2018;33:316e9. [24] Weiser MC, Kim KY, Anoushiravani AA, Iorio R, Davidovitch RI. Outpatient total hip arthroplasty has minimal short-term complications with the use of institutional protocols. J Arthroplasty 2018;33:3502e7.