Total Hip Arthroplasty and the Medicare Inpatient-Only List: An Analysis of Complications in Medicare-Aged Patients Undergoing Outpatient Surgery

Efficacy and Safety of a Patient Selection Tool for Predicted Discharge at an Ambulatory Surgical Center: A Pilot Study

Background

There is a paucity of validated risk stratification tools to assess which patients can safely and predictably undergo outpatient total hip (THA) or knee arthroplasty (TKA) in an ambulatory surgery center (ASC).

Methods

Our novel patient selection tool was prospectively applied to 190 consecutive primary THA and TKA performed by a single surgeon at a single ASC. We identified the proportion of patients discharged home the same day, those requiring a one-night stay, or those with failed discharge within 23 hours. A retrospective chart review was performed to determine if any demographic parameters were risk factors for an overnight stay.

Results

Overall, 190 (100%) patients selected for outpatient THA and TKA were discharged home within 23 hours. One hundred and four patients (55%) were discharged the same day of surgery, whereas 86 (45%) required overnight stay and were discharged on postoperative day 1. Female sex (odds ratio [OR]: 4.1, 95% confidence interval [CI]: 2.0-8.2, P < .001), THA (OR: 2.5, 95% CI: 1.1-5.5, P = .022), and heavier body mass index (OR: 1.0, 95% CI: 1.0-1.2, P = .022) were identified as independent risk factors for staying overnight in the ASC.

Conclusions

In this pilot study, we found that 100% of outpatient THA and TKA-eligible patients were able to be discharged home by postoperative day 1. Additionally, we found that this selection tool is safe and effective at predicting short-stay discharge in an ASC.

Safety Considerations for Outpatient Arthroplasty

Since 2018, the number of total joint arthroplasties (TJAs) performed on an outpatient basis has dramatically increased. Both surgeon and anesthesiologist should be aware of the implications for the safety of outpatient TJAs and potential patient risk factors that could alter this safety profile. Although smaller studies suggest that the risk of negative outcomes is equivalent when comparing outpatient and inpatient arthroplasty, larger database analyses suggest that, even when matched for comorbidities, patients undergoing outpatient arthroplasty may be at increased risk of surgical or medical complications. Appropriate patient selection is critical for the success of any outpatient arthroplasty program. Potential exclusion criteria for outpatient TJA may include age greater than 75 years, bleeding disorder, history of deep vein thrombosis, uncontrolled diabetes mellitus, and hypoalbuminemia, among others. Patient optimization before surgery is also warranted. The potential risks of same-day versus next-day discharge have yet to be elicited in a large-scale manner.

Risk Factors for Early Readmission and Reoperation After Outpatient Total Hip Arthroplasty

Outpatient total hip arthroplasty (THA) is a safe option for select patients. The purpose of this study was to analyze a national database and understand risk factors that lead to unplanned early readmission and reoperation after outpatient THA. The National Surgical Quality Improvement Program database was used to collect outpatient THAs performed from 2013 to 2020. The outpatient setting was defined as a reported hospital length of stay of 23 hours or less. Data variables collected included patient demographics, medical comorbidities, American Society of Anesthesiologists classification, functional status, preoperative laboratory values, National Surgical Quality Improvement Program morbidity probability, and 30-day readmissions and reoperations. A total of 15,055 patients underwent outpatient THA. Mean age was 62.6 years, and 52.1% of patients were men. Mean body mass index was 29.3 kg/m2. The overall rate of readmission was 1.8%, and the reoperation rate was 1.0%. Patients with a 30-day readmission were older (P<.01), with a higher incidence of hypertension (P<.01), steroid use (P<.01), and bleeding disorders (P=.01). Patients with a 30-day reoperation had higher body mass index (P<.01), hypertension (P<.01), and steroid use (P<.01). Regression analysis demonstrated that independent risk factors for readmission were age (P<.01) and steroid use (P<.01). Risk factors for 30-day reoperation were hypertension (P<.01) and steroid use (P<.01). There is a higher risk of early readmission after outpatient THA for older patients with hypertension, bleeding disorders, and steroid use. Patients with hypertension and steroid use have a higher risk for reoperation after outpatient THA. Modifiable risk factors should be addressed preoperatively, with proper patient selection for outpatient THA. [Orthopedics. 2024;47(1):e38-e44.].

Safety of Outpatient Total Hip Arthroplasty Performed in Patients 65 Years of Age and Older in an Ambulatory Surgery Center

Studies regarding the safety of same day discharge (SDD) in patients ≥65 years of age undergoing total hip arthroplasty (THA) are lacking. A retrospective review of 69 patients undergoing SDD following primary THA in 2 free-standing ambulatory surgical centers (ASCs) was performed to evaluate for safety and complications. Sixty-six patients met SDD goals, while 1 patient required transport to a hospital for transfusion, and 2 patients underwent overnight observation in the ASC. This study reveals that with appropriate preoperative evaluation, patient selection, and education, THA in a free-standing ASC can be safely performed in patients ≥65 years of age.

Inconsistent Classification of "Outpatient" Surgeries Leads to Different Outcomes Following Total Hip Arthroplasty in Medicare Beneficiaries: A Critical Analysis

BACKGROUND

With rising utilization of outpatient total hip arthroplasty (THA) in older patients including Medicare beneficiaries, the objective was to compare differences in definition including (1) patient demographics; (2) lengths of stay (LOS); and (3) outcomes of "outpatient" (stated status) versus "same-day discharge" (SDD) (actual LOS = 0 days) utilizing a nationwide database.

METHODS

A national database from 2015 to 2019 was queried for Medicare-aged patients undergoing outpatient THA. Total outpatient THAs (N = 6,072) were defined in one of 2 ways: either "outpatient" by the hospital (N = 2,003) or LOS = 0 days (N = 4,069). Demographics, LOS, discharge destinations, and complications were compared between groups. Logistic regression models computed odds ratios (ORs) for factors leading to complications, readmissions, and nonhome discharges. P values < .008 were significant.

RESULTS

Women (OR: 1.19, P = .002), diabetes mellitus (OR: 1.31, P = .003), general anesthesia (OR: 1.24, P = .001), and longer operative times (≥95 minutes) (OR: 1.82, P < .001) were associated with 'outpatient' designation versus SDD. Within the hospital-defined 'outpatient' cohort, 49.1% (983 of 2,003) were discharged the same day (LOS = 0 days), and 21.8% had LOS 2 or more days. The hospital-defined 'outpatient' cohort had greater odds of nonhome discharges (6.3 versus 2.8%; OR: 1.88, P < .001) compared to SDD surgeries. The incidence was higher for any complication among hospital-defined 'outpatient' designated patients compared to SDD (5.5 versus 3.9%, P = .007).

CONCLUSIONS

Outpatient surgeries may be misleading and often do not correlate with SDD, as over 20% remain in the hospital 2 or more days. Investigators should quantitatively define the "outpatient" status by actual LOS to allow standardization and results comparison.

LEVEL OF EVIDENCE

III.

The Same Day Discharges following Primary Total Knee Arthroplasty: A Single Surgeon, Propensity Score-Matched Cohort Analysis

This is a retrospective study. As new surgical techniques and improved perioperative care approaches have become available, the same-day discharge in selected total knee arthroplasty (TKA) patients was introduced to decrease health care costs without compromising outcomes. This study aimed to compare clinical and functional outcomes between same-day discharge TKA patients and inpatient-discharge TKA patients. A retrospective review of 100 consecutive patients with same-day discharge matched to a cohort of 300 patients with inpatient discharge that underwent TKA by a single surgeon at a tertiary referral center was conducted. Propensity-score matching was performed to adjust for baseline differences in preoperative patient demographics, medical comorbidities, and patient-reported outcome measures (PROMs) between both cohorts. All patients had a minimum of 1-year follow-up (range: 1.2-2.8 years). In terms of clinical outcomes for the propensity score-matched cohorts, there was no significant difference in terms of revision rates (1.0 vs. 1.3%, p = 0.76), 90-day emergency department visits (3.0 vs. 3.3%, p = 0.35), 30-day readmission rates (1.0 vs. 1.3%, p = 0.45), and 90-day readmission rates (3.0 vs. 3.6%, p = 0.69). Patients with same-day discharge demonstrated significantly higher postoperative PROM scores, at both 3-month and 1-year follow-up, for PROMIS-10 Physical Score (50 vs. 46, p = 0.028), PROMIS-10 Mental Score (56 vs. 53, p = 0.039), and Physical SF10A (57 vs. 52, p = 0.013). This study showed that patients with same-day discharge had similar clinical outcomes and superior functional outcomes, when compared with patients that had a standard inpatient protocol. This suggests that same-day discharge following TKA may be a safe, viable option in selected total knee joint arthroplasty patients.

Outpatient Total Joint Arthroplasty: Are We Closing the Racial Disparities Gap?

INTRODUCTION

As ne arly half of all total joint arthroplasty (TJA) procedures are projected to be performed in the outpatient setting by 2026, the impact of this trend on health disparities remains to be explored. This study investigated the racial/ethnic differences in the proportion of TJA performed as outpatient as well as the impact of outpatient surgery on 30-day complication and readmission rates.

METHODS

The ACS National Surgical Quality Improvement Program was retrospectively reviewed for all patients who underwent primary, elective total hip and knee arthroplasty (THA, TKA) between 2011 and 2018. The proportion of TJA performed as an outpatient, 30-day complications, and 30-day readmission among African American, Hispanic, Asian, Native American/Alaskan, and Hawaiian/Pacific Islander patients were each compared to White patients (control group). Analyses were performed for each racial/ethnic group separately. A general linear model (GLM) was used to calculate the odds ratios for receiving TJA in an outpatient vs. inpatient setting while adjusting for age, gender, body mass index (BMI), functional status, and comorbidities.

RESULTS

In total, 170,722 THAs and 285,920 TKAs were analyzed. Compared to White patients, non-White patients had higher likelihood of THA or TKA performed as an outpatient (OR 1.31 and 1.24 respectively for African American patients, OR 1.65 and 1.76 respectively for Hispanic patients, and OR 1.66 and 1.59 respectively for Asian patients, p < 0.001). Outpatient surgery did not lead to increased complications in any of the study groups compared to inpatient surgery (p > 0.05). However, readmission rates were significantly higher for outpatient TKA in all the study groups compared to inpatient TKA (OR range 2.47-10.15, p < 0.001). Complication and readmission rates were similar between inpatient and outpatient THA for all the study groups.

CONCLUSION

While this study demonstrated higher proportion of TJA performed as an outpatient among most non-White racial/ethnic groups, this observation should be tempered with the increased readmission rates observed in outpatient TKA, which could further the disparities gap in health outcomes.

Accelerated Discharge After Aseptic Revision Total Hip Arthroplasty Does Not Predict Inferior 30-Day Outcomes

BACKGROUND

Perioperative advancements have made outpatient primary total hip arthroplasty (THA) a viable option for patients. This study evaluated the feasibility of expedited discharge after revision THA and compared 30-day outcomes to patients who had prolonged inpatient hospitalizations. The authors hypothesized that expedited discharge would not result in inferior 30-day outcomes.

METHODS

Aseptic revision THAs in a national database were reviewed from 2013 to 2020. THAs were stratified by hospital length of stay (LOS) more or less than 24 hours. Demographics, comorbidities, preoperative laboratory values, American Society of Anesthesiology (ASA) scores, operative times, components revised, 30-day readmissions, and reoperations were compared. Multivariable analyses evaluated predictors of discharge prior to 24 hours, 30-day readmissions, and reoperations. Of 17,044 aseptic revision THAs, 211 were discharged within 24 hours.

RESULTS

Accelerated discharge patients were younger, mean age 63 years (range, 20-92) versus 66 years (range, 18-94) (P < .01) had lower body mass index, mean 28.7 (range, 18.3-46.4) versus 29.9 (range, 17.3-52.5) (P = .01), and ASA scores (ASA, 1-2; 40.4-57.8%) (P < .01). Components revised had no association with LOS (P = .39); however, operative times were shorter and mean 100 minutes (range, 35-369) versus 139 minutes (range, 24-962) (P < .01) in accelerated discharge patients. Accelerated discharge patients had lower readmission rates (P < .01) but no difference in reoperation rates (P = .06).

CONCLUSION

Discharge less than 24 hours after revision THA is a feasible option for the correct patient and further efforts to decrease LOS should be evaluated.

Chronic Obstructive Pulmonary Disease is Associated With Serious Infection and Venous Thromboembolism in Patients Undergoing Hip or Knee Arthroplasties: A Meta-Analysis of Observational Studies

BACKGROUND

Although previous studies evaluated postoperative outcomes of arthroplasty patients with chronic obstructive pulmonary disease (COPD), no meta-analysis has been conducted.

METHODS

An electronic search was conducted on PubMed, Embase, and Cochrane Library databases to identify relevant studies published from inception to May 1, 2022. To assess the impact of COPD on postoperative outcomes, the odds ratios and 95% confidence intervals were calculated; pooled results were calculated using a random effects model. Sensitivity and subgroup analyses were carried out according to surgical type and statistical method. A total of 11 retrospective cohort studies involving patients with COPD who underwent hip or knee arthroplasties were included in the meta-analysis. There were 195,444 patients with COPD and 1,592,908 patients without COPD.

RESULTS

A pooled analysis showed that the COPD group was at higher risk for mortality, readmission, pneumonia, sepsis, septic shock, and surgical site infection within 30 days following hip arthroplasties than the non-COPD group. Moreover, COPD patients were more likely to experience mortality, readmission, pneumonia, sepsis, septic shock, and surgical site infection 30 days after knee arthroplasties.

CONCLUSION

In this study, coexisting COPD was associated with worse outcomes in patients with lower extremity joint arthroplasties. The findings highlighted the importance of preoperative optimization and proactive interventions for COPD in the perioperative period.

Hospital Revenue, Cost, and Contribution Margin in Inpatient Versus Outpatient Primary Total Joint Arthroplasty

BACKGROUND

Removal of primary total knee arthroplasty (TKA) and primary total hip arthroplasty (THA) from the inpatient-only list has financial implications for both patients and institutions. The aim of this study was to evaluate and compare financial parameters between patients designated for inpatient versus outpatient total joint arthroplasty.

METHODS

We reviewed all patients who underwent TKA or THA after these procedures were removed from the inpatient-only list. Patients were statistical significance into cohorts based on inpatient or outpatient status, procedure type, and insurance type. This included 5,284 patients, of which 4,279 were designated inpatient while 1,005 were designated outpatient. Patient demographic, perioperative, and financial data including per patient revenues, total and direct costs, and contribution margins (CMs) were collected. Data were compared using t-tests and Chi-squared tests.

RESULTS

Among Medicare patients receiving THA, CM was 89.1% lower for the inpatient cohort when compared to outpatient (P < .001), although there was no statistical significance difference between cohorts for TKA (P = .501). Among patients covered by Medicaid or Government-managed plans, CM was 120.8% higher for inpatients receiving THA (P < .001) when compared to outpatients and 136.3% higher for inpatients receiving TKA (P < .001).

CONCLUSION

Our analyses showed that recent costs associated with inpatient stay inconsistently match or outpace additional revenue, causing CM to vary drastically depending on insurance and procedure type. For Medicare patients receiving THA, inpatient surgery is financially disincentivized leaving this vulnerable patient population at a risk of losing access to care.

LEVEL III EVIDENCE

Retrospective Cohort Study.

Same-Day Discharge Total Knee Arthroplasty in Octogenarians

BACKGROUND

One of the most important aspects of the transition to outpatient (OP) arthroplasty is patient selection, with guidance traditionally recommending that OP total knee arthroplasty (TKA) be reserved for patients <80 years old. However, there are limited data as to whether older age should really be considered a contraindication to OP-TKA. The purpose of this study is to assess the risk of complications and readmissions following OP-TKA in patients ≥80 years old.

METHODS

This is a retrospective, propensity-matched cohort study of the National Surgical Quality Improvement Program database from 2011 to 2019. Patients ≥80 years undergoing OP (same-day discharge) TKA were propensity matched to patients ≥80 years undergoing inpatient (IP) TKA based on age, gender, race, body mass index, American Society of Anesthesiologists classification, functional status, smoking status, anesthetic type, and medical comorbidities. There were 1,418 patients (709 IPs and 709 OPs) included. All baseline factors were successfully matched between IP-TKA versus OP-TKA (P ≥ .18 for all). Thirty-day complications, readmissions, reoperations, and mortality were subsequently analyzed.

RESULTS

Thirty-day readmission rates were identical between patients undergoing IP-TKA and OP-TKA (3.5% versus 3.5%, P = 1.0). Similarly, there was no significant difference in the incidence of major complications (2.7% versus 2.0%, P = .38), reoperations (1.3% versus 0.8%, P = .44), or mortalities (0.3% versus 0.3%, P = 1.0) within 30 days.

CONCLUSION

Octogenarians undergoing OP-TKA had comparable complication rates to similar patients undergoing IP-TKA. OP-TKA can be performed safely in select octogenarians and age ≥80 years likely does not need to be a uniform contraindication to OP-TKA.

Trends in Revenue, Cost, and Contribution Margin for Total Joint Arthroplasty 2011-2021

BACKGROUND

Regulatory change has created a growing demand to decrease the hospital costs associated with primary total joint arthroplasty (TJA). Concurrently, the removal of lower extremity TJA from the in-patient only list has affected hospital reimbursement. The purpose of this study is to investigate trends in hospital revenue versus costs in primary TJA.

METHODS

We retrospectively reviewed all patients who underwent primary TJA from June 2011 to May 2021 at our institution. Patient demographics, revenue, total cost, direct cost, and contribution margin were collected. Changes over time as a percentage of 2011 numbers were analyzed. Linear regression analysis was used to determine overall trend significance and develop projection models.

RESULTS

Total knee arthroplasty (TKA) insured by government-managed/Medicaid (GMM) plans showed a significant upward trend (P = .013) in total costs. Direct costs of TKA across all insurance providers (P = .001 and P < .001) and total hip arthroplasty (THA) for Medicare (P = .009) and GMM (P = .001) plans demonstrated significant upward trends. Despite this, 2011-2021 modeling found no significant change in contribution margin for TKA and THA covered under all insurance plans. However, models based on 2018-2021 financial data demonstrated a significant downward trend in contribution margin across Medicare (P < .001) and GMM (P < .001) insurers for both TKA and THA.

CONCLUSION

Physician-led innovation in cost-saving strategies has maintained contribution margin over the past decade. However, the increase in direct costs seen over the past few years could lead to negative contribution margins over time, if further efficiency and cost-saving measures are not developed.

LEVEL III EVIDENCE

Retrospective Cohort Study.

Outcomes and Cost Analysis of a Surgical Care Unit for Outpatient Total Joint Arthroplasties Performed at a Tertiary Academic Center

Background

Methods

Results

Conclusions

Outpatient total knee and hip arthroplasty present comparable and even better clinical outcomes than inpatient operation

Background

The purpose of this study was to compare total complications, complications stratified by type, readmissions, and reoperations at 30 and 90 days after outpatient and standard inpatient total knee and total hip arthroplasty (TKA, THA).

Methods

A literature search was conducted from the PubMed, Cochrane Library, and Embase databases for articles published before 20 August 2021. The types of studies included prospective randomized controlled trials, prospective cohort studies, retrospective comparative studies, retrospective reviews of THA and TKA registration databases, and observational case-control studies. Comparisons of interest included total complications, complications stratified by type, readmissions, and reoperations at 30 and 90 days. The statistical analysis was performed using Review Manager 5.3.

Results

Twenty studies with 582,790 cases compared relevant postoperative indicators of outpatient and inpatient total joint arthroplasty (TJA) (TKA and THA). There was a significant difference in the total complications at 30 days between outpatient and inpatient THA (p = 0.001), readmissions following TJA (p = 0.03), readmissions following THA (p = 0.001), stroke/cerebrovascular incidents following TJA (p = 0.01), cardiac arrest following TJA (p = 0.007), and blood transfusions following TJA (p = 0.003). The outcomes showed an obvious difference in 90-day total complications between outpatient and inpatient TJA (p = 0.01), readmissions following THA (p = 0.002), and surgical-related pain following TJA (p < 0.001). We did not find significant differences in the remaining parameters.

Conclusion

Outpatient procedures showed comparable and even better outcomes in total complications, complications stratified by type, readmissions, and reoperations at 30 and 90 days compared with inpatient TJA for selected patients.

Same Day Joint Replacement Surgery: Patient Selection and Perioperative Management

Joint replacements are increasingly performed as outpatient surgeries. The push toward ambulatory joint arthroplasty is driven in part by the changing current health care economics and reimbursement models. Patients' selection and well-designed perioperative care pathways are critical for the success of these procedures. The rate of complications after outpatient joint arthroplasty is comparable to the rate of complications in the ambulatory setting. Patient education, adequate social support, multimodal analgesia, regional anesthesia are key ingredients to the ambulatory care pathway after joint arthroplasty. Motor sparing nerve blocks are often used in these settings. Implementation of the elements of fast protocols can result in overall improvement of outcome metrics for all patients undergoing joint arthroplasty, including reduced length of stay and increased rate of home discharge.

Short-Stay Arthroplasty is Not Associated With Increased Risk of 90-Day Hospital Returns

BACKGROUND

With the removal of total hip arthroplasty (THA) and total knee arthroplasty (TKA) from the inpatient-only list, medical centers are faced with challenging transitions to outpatient surgery. We investigated if short-stay arthroplasty, defined as length of stay (LOS) <24 hours, would influence 90-day readmissions and emergency department (ED) visits at a tertiary referral center.

METHODS

The institutional database was retrospectively queried for primary TKAs and THAs from July 2015 to January 2018, resulting in 2,217 patients (1,361 TKA and 856 THA). Patient demographics, including age, gender, body mass index, and American Society of Anesthesiologists score were collected. LOS, disposition, cost of care, 90-day ED visits, and readmissions were identified through the institutional database using electronic medical record data. Univariable and multivariable models were used to evaluate rates of 90-day readmissions and ED visits based on LOS <24 hours vs ≥24 hours.

RESULTS

LOS <24 h was associated with significant decreases in 90-day ED visits (P = .003) and readmissions (P = .002). After controlling for potential confounding variables with a multivariable model, a significant decrease in ED visits (P = .034) remained in the THA cohort alone. Within TKA and THA cohorts, LOS <24 h was associated with lower costs (P < .001). Eighteen percent of patients with ≥24 h LOS were discharged to skilled nursing or rehabilitation facilities.

CONCLUSION

In this cohort, LOS <24 hours was associated with decreased 90-day readmissions, ED visits, and costs. With the goal of minimizing costs and maintaining patient safety while efficiently using resources, outpatient and short-stay arthroplasty are valuable, feasible options in tertiary academic centers.

Surgeon and Facility Volumes Are Associated With Social Disparities and Post-Operative Complications After Total Hip Arthroplasty

BACKGROUND

The purpose of this study is to further characterize the volume dependence of facilities and surgeons on morbidity and mortality after total hip arthroplasty (THA).

METHODS

Adults who underwent THA from 2009 to 2014 were identified using International Classification of Diseases, Ninth Revision, Clinical Modification and Procedural codes in the New York Statewide Planning and Research Cooperative System database. Complication rates were compared across surgeon and facility volumes using multivariable Cox proportional hazards regression controlling for factors such as the Social Deprivation Index. Surgeon and facility volumes were compared between the low and high volume using cutoffs established by prior research.

RESULTS

In total, 99,832 patients were included. Low volume facilities had higher rates of readmission, urinary tract infection (UTI), acute renal failure, pneumonia, surgical site infection (SSI), cellulitis, wound complications, deep vein thrombosis (DVT), in-hospital mortality, and revision. Low volume surgeons had higher rates of readmission, UTI, acute renal failure, pneumonia, SSI, acute respiratory failure, pulmonary embolism, cellulitis, wound complications, in-hospital mortality, cardiorespiratory arrest, DVT, and revision. African Americans, Hispanics, and those with federal insurance had increased rates of readmission. Those with ≥1 Charlson comorbidities or from areas of higher social deprivation had increased incidence of treatment by low volume surgeons and facilities.

CONCLUSION

Both low volume facilities and surgeons performing primary THA have higher rates of readmission, UTI, acute renal failure, pneumonia, SSI, cellulitis, wound complications, DVT, in-hospital mortality, and revision. Demographic disparities exist between who is treated at low vs high volume surgeons and facilities placing those groups at higher risks for complications.

Social Determinants of Health in Total Hip Arthroplasty: Are They Associated With Costs, Lengths of Stay, and Patient Reported Outcomes?

BACKGROUND

Social determinants of health (SDOH) may play a larger role in predicting patient outcomes as outpatient total hip arthroplasty (THA) expands. We specifically examined the association between SDOH and patient metrics (demographics and comorbidities) for: (1) 30-day post-discharge costs of care; (2) lengths of stay (LOS); and (3) patient-reported outcomes (Hip Disability and Osteoarthritis Outcomes Score for Joints Replacement (HOOS JR)).

METHODS

Medicare patients who underwent primary THA between 2018 and 2019 were identified. Those who had complete social determinant data were included (n = 136). Data elements were drawn from institutional, regional, and government databases, as well as the Social Vulnerability Index (SVI). Multiple regression analyses were performed to determine SDOH and baseline comorbidities associations with costs, LOS, and HOOS JR scores.

RESULTS

Various SDOH factors were associated with higher 30-day costs, including residing in a food desert ($53,695 ± 15,485; P < .001) and the following SVI themes: 'Minority Status and Language' ($24,075 ± 9845; P = .01) and 'Housing and Transportation' ($16,190 ± 8501; P = .06), although the latter did not meet statistical significance. Baseline depression was associated with longer LOS (P = .02), while none of the other SDOH or patient metrics affected LOS. No relationships were observed between SDOH and HOOS JR changes from baseline.

CONCLUSION

Patients who live in food deserts and have minority status had higher costs of care after primary THA. Poor housing and transportation may also increase costs, albeit insignificantly. These results highlight the utility of assessing SDOH-related risk factors to optimize post-operative outcomes, with potential implications for bundled care.

Factors Predictive of Early Complications Following Total Ankle Arthroplasty

Background:

The safety of outpatient total ankle arthroplasty (TAA), and factors predictive of early complications are poorly understood. The objective of this study was to determine the frequency of early complications in patients undergoing outpatient TAA compared to a matched inpatient TAA cohort. Factors predictive of early complications following TAA are elucidated.

Methods:

A retrospective review of prospectively collected data from the 2011-2018 American College of Surgeons–National Surgical Quality Improvement Program (ACS-NSQIP) database was performed. An unadjusted analysis comparing complication rates in outpatient, and inpatient TAA was performed followed by a propensity score–matched cohort analysis. A multivariate logistic regression model was then used to identify significant independent predictors for complications, reoperation, and readmission following TAA.

Results:

A total of 1487 patients (198 outpatient, 1289 inpatient) undergoing TAA were included in the study. Inpatient TAA was associated with increased 30-day readmission compared with outpatient TAA (3.54% vs 0.51%, P = .032) in a matched cohort analysis. Thirty-eight (2.6%) patients had a minor complication, with 16 (1.1%) patients having a major complication after TAR. Nineteen (1.3%) patients underwent reoperation, and 42 (2.8%) patients were readmitted within 30 days of the index TAR. Multivariate analysis identified factors predictive of early complications to include length of stay (LOS) >2 days, smoking, hypertension, bleeding disorders, and diabetes mellitus.

Conclusion:

From this relatively limited data set, outpatient TAA appears to be safe for management of end-stage ankle arthritis in select patients. Inpatient status was associated with an increased rate of 30-day readmission following TAA. Postoperative length of stay >2 days, smoking, hypertension, bleeding disorders, and diabetes mellitus were identified to be associated with early postoperative complications following TAA in this cohort.

Level of Evidence

Level III, retrospective cohort study.

Safety Considerations for Outpatient Arthroplasty

Since 2018, the number of total joint arthroplasties (TJAs) performed on an outpatient basis has dramatically increased. Both surgeon and anesthesiologist should be aware of the implications for the safety of outpatient TJAs and potential patient risk factors that could alter this safety profile. Although smaller studies suggest that the risk of negative outcomes is equivalent when comparing outpatient and inpatient arthroplasty, larger database analyses suggest that, even when matched for comorbidities, patients undergoing outpatient arthroplasty may be at increased risk of surgical or medical complications. Appropriate patient selection is critical for the success of any outpatient arthroplasty program. Potential exclusion criteria for outpatient TJA may include age greater than 75 years, bleeding disorder, history of deep vein thrombosis, uncontrolled diabetes mellitus, and hypoalbuminemia, among others. Patient optimization before surgery is also warranted. The potential risks of same-day versus next-day discharge have yet to be elicited in a large-scale manner.

The American College of Surgeons National Surgical Quality Improvement Program surgical risk calculator is not reliable in predicting complications and length of stay after primary total hip arthroplasty at an institution implementing clinical pathways

INTRODUCTION

The authors aimed to: (1) determine how length of stay (LOS) and complication rates changed over the past 10 years, in comparison to values estimated by the ACS-NSQIP surgical risk calculator, at a single private institution open to external surgeons; and (2) determine preoperative patient factors associated with complications.

METHODS

We retrospectively assessed 1018 consecutive patients who underwent primary elective THA over 10 years. We excluded 87 with tumours and 52 with incomplete records. Clinical data of the remaining 879 were used to determine real LOS and rate of 9 adverse events over time, as well as to estimate these values using the risk calculator. Its predictive reliability was represented on receiver operating characteristic curves. Multivariable analyses were performed to determine associations of complications with age, sex, ASA score, diabetes, hypertension, heart disease, smoking and BMI.

RESULTS

Over the 10-year period, real LOS and real complication rates decreased considerably, while LOS and complication rates estimated by the surgical risk calculator had little or no change. The difference between real and estimated LOS decreased over time. The overall estimated and real rates of any complication were respectively 3.3% and 2.8%. The risk calculator had fair reliability for predicting any complications (AUC 0.72). Overall estimated LOS was shorter than the real LOS in 764 (86.9%) patients. Multivariable analysis revealed risks of any complication to be greater in patients aged ⩾75 (OR = 4.36, p = 0.002), and with hypertension (OR = 3.13, p = 0.016).

CONCLUSIONS

Since the implementation of clinical pathways at our institution, real LOS and complication rates decreased considerably, while LOS and complication rates estimated by the surgical risk calculator had little or no change. The difference between real and estimated LOS decreased over time, which could lead some clinicians to reconsider their discharge criteria, knowing that advanced age and hypertension increased risks of encountering complications.

Recent Increases in Outpatient Total Hip Arthroplasty Have Not Increased Early Complications

BACKGROUND

Outpatient total hip arthroplasty (THA) has increased in recent years. Recent regulatory changes may allow and incentivize outpatient THA in more patients; however, there are concerns regarding safety. The purpose of this study is to assess early complications in outpatient THA compared to longer hospitalization.

METHODS

We identified patients undergoing primary THA in the National Surgical Quality Improvement Program database between 2015 and 2018. Patients were stratified by length of stay (LOS): 0 days (LOS 0), 1-2 days, and ≥3 days. Thirty-day rates of any complication, wound complications, readmissions, and reoperation were assessed. Multivariate analysis was performed.

RESULTS

In total, 4813 (4%) patients underwent outpatient THA, 84,627 (64%) had LOS of 1-2 days, and 42,293 (32%) had LOS ≥3 days. LOS 0 patients were younger, had lower body mass index, and less medical comorbidities compared to those with postsurgical hospitalization. Any complication was experienced in 3.2% of the LOS 0 group, 5.3% of the LOS 1-2 group, and 15.6% for the LOS ≥3 group (P < .0001). Readmission rates were 1.6%, 2.6%, and 4.7% for the 3 groups, respectively (P < .0001). After controlling for confounding variables, patients with LOS 1-2 days had higher odds for any complication (odds ratio 1.56 [1.32-1.83) and readmission (odds ratio 1.41 [1.12-1.78]) compared to LOS 0 days. Patients with LOS ≥3 days had higher odds for complications compared to LOS 0 or 1-2 days.

CONCLUSION

Outpatient THA had lower odds for readmission or complications compared to LOS 1-2 days. Despite increased outpatient surgery, many patients had postsurgical hospitalization and, due to patient factors, this remains an integral patient of post-THA care.

Extended length of stay and postoperative complications in octogenarians with hypertension following revision total knee arthroplasty

BACKGROUND

Prior studies have shown hypertensive patients to be at an increased risk of postoperative complications following various surgeries, including revision total knee arthroplasty (rTKA). However, whether these risks are compounded in octogenarian patients has not yet been well explored. The purpose of this study was to analyze whether hypertensive octogenarians, aged 80 to 89, undergoing rTKA are at an increased risk of postoperative complications relative to the younger hypertensive geriatric population aged 65 to 79.

METHODS

A national database was used to collect data for all hypertensive patients who underwent rTKA from 2006 to 2018. Patients were stratified into an aged 65 to 79 cohort and an aged 80 to 89 cohort. Demographics, medical comorbidities, and postoperative complications were compared between the two cohorts. Bivariate and multivariate analyses were performed.

RESULTS

Of the 6,599 hypertensive patients who underwent rTKA, 5,477 (83.0%) patients were in the aged 65 to 79 group and 1,122 (17.0%) patients were in the aged 80 to 89 group. Following adjustment to control for demographic and comorbidity data, relative to patients in the 65 to 79 age group, hypertensive patients who were 80-89 years old had an increased risk of unplanned reintubation (OR 3.52; p = 0.008), urinary tract infection (OR 2.08; p = 0.011), postoperative transfusion (OR 1.90; p < 0.001), myocardial infarction (OR 2.55; p = 0.017), and extended length of hospital stay (OR 1.77; p < 0.001).

CONCLUSION

Hypertensive octogenarian patients undergoing rTKA have an increased risk of an extended length of stay and other postoperative complications relative to their younger hypertensive geriatric counterparts. Orthopaedic surgeons should consider a multi-disciplinary approach to managing hypertension in these octogenarian patients prior to surgery to minimize this risk. However, even with this risk, an octogenarian age should not be used independently in evaluating if a hypertensive geriatric patient is a safe rTKA candidate.

A Risk Stratification Nomogram to Predict Inpatient Admissions After Total Shoulder Arthroplasty Among Patients Eligible for Medicare

The goal of this study was to establish a risk stratification nomogram to aid in determining the need for inpatient admission among patients who were eligible for Medicare and were undergoing primary total shoulder arthroplasty (TSA). The American College of Surgeons National Surgical Quality Improvement Program database was queried to identify all patients older than 65 years who underwent primary TSA between 2006 and 2016. The primary outcome measure was inpatient admission, as defined by hospital length of stay longer than 2 days. Multiple demographic, comorbid, and peri-operative variables were used in a multivariate logistic regression model to yield a risk stratification nomogram. A total of 1514 inpatient and 6020 out-patient admissions were analyzed. Age older than 80 years (odds ratio [OR], 2.69; P<.0001; 95% CI, 2.21-3.27), female sex (OR, 2.18; P<.0001; 95% CI, 1.90-2.51), dependent functional status (OR, 1.69; P<.0001; 95% CI, 1.2-2.38), dialysis (OR, 3.48; P=.029; 95% CI, 1.14-10.63), admission from an inpatient facility (OR, 1.76; P<.0001; 95% CI, 1.70-1.82), and inflammatory arthritis (OR, 1.69; P<.02; 95% CI, 1.25-13.78) were the greatest determinants of inpatient stay. The resulting predictive model showed acceptable discrimination and calibration. Our model enabled reliable and straightforward identification of the most suitable candidates for inpatient admission among patients who were eligible for Medicare and were undergoing primary TSA. Patients who were receiving dialysis, who had dyspnea at rest, and who had bleeding disorders were more likely to be admitted as inpatients after TSA. Larger multicenter studies are necessary to externally validate the proposed predictive nomogram. [Orthopedics. 2022;45(1):43-49.].

The cost-effectiveness of outpatient surgery for primary total hip arthroplasty in the United States: a computer-based cost-utility study

PURPOSE

The purpose of this study was to perform a cost-effectiveness analysis of outpatient versus inpatient total hip arthroplasty (THA) in the USA, considering complication probability and the potential cost of such complications.

METHODS

A cost-effectiveness analysis was conducted from the societal perspective to evaluate the incremental cost and effectiveness of inpatient THA compared to outpatient THA over a lifetime horizon. Effectiveness was expressed in quality-adjusted life years (QALYs). Costs, expressed in 2019 US dollars, transition probabilities, and health utilities were derived from the literature. The primary outcome was the incremental cost-effectiveness ratio (ICER), with a willingness to pay (WTP) threshold set at $50,000/QALY. 1-way and probabilistic sensitivity analyses was performed to evaluate the effect of the various variables on the model.

RESULTS

In the base case, inpatient THA was more effective in terms of total utility (10.36 vs. 10.30 QALY), but also more costly ($48,155 ± 1673 vs. $43,288 ± 1, 606 for Medicare) than outpatient THA. Even with a lifetime horizon, the ICER was $81,116 per QALY and $140,917 per QALY for Medicare and private payer insurance, respectively, which is higher than the willingness to pay threshold. 1-way sensitivity analyses indicated that the variables having the most influence on the model were the utility of inpatient and outpatient THA and cost of inpatient and outpatient THA.

CONCLUSIONS

This model determined that for a WTP threshold set at $50,000/QALY, outpatient THA is more cost-effective than inpatient THA from a societal perspective. Despite this, surgeons must weigh clinical factors first and foremost in determining if an individual patient can be safely operated on in the outpatient setting.

Blood Management in Outpatient Total Hip Arthroplasty

Based on a series of 407 outpatient total hip arthroplasties performed by a single surgeon, a standardized protocol for blood loss management in outpatient arthroplasty was developed consisting of a presurgical hematocrit of greater than 36%, administration of tranexamic acid, prophylactic introduction of albumin, hypotensive epidural anesthesia, monopolar electrocautery, and bipolar sealer. This protocol uses techniques that alone are not novel but together create a standardized and reproducible pathway that when implemented can increase the safety of outpatient hip arthroplasty.

Out-of-Network Facility Charges for Patients Undergoing Outpatient Total Joint Arthroplasty

BACKGROUND

The utilization of outpatient (OP) total joint arthroplasty (TJA) is increasing. Although many arthroplasty surgeons and hospitals have longstanding agreements with insurance companies, it may take time for ambulatory surgery centers (ASCs) to establish in-network agreements. The purposes of this study are to investigate trends in out-of-network facility charges for OP-TJA, as well as compare rates of out-of-network facilities between ASC and hospital outpatient department (HOPD) OP-TJA.

METHODS

This is a retrospective study of the MarketScan commercial claims database of OP-TJAs (same-day discharge) performed at ASCs or HOPDs from 2007 to 2017. Detailed demographic, geographic, operative, insurance, temporal, and financial details were collected. Out-of-network facility utilization was trended over time. Adjusted regressions compared the prevalence of out-of-network facilities between ASCs and HOPDs.

RESULTS

There were 13,031 OP-TJA patients (58.8% total knee arthroplasty). Utilization of out-of-network facilities significantly decreased over time, from 27.8% of surgeries in 2007 to 9.5% in 2017 (P_trend < .001); however, this was non-linear with a significant increase in 2013-2015 corresponding to rising use of out-of-network ASCs. Patients treated at ASCs were significantly more likely to be out-of-network than those treated at HOPDs (odds ratio 4.88, 95% confidence interval 4.28-5.57, P < .001; odds ratio 7.70, 95% confidence interval 6.42-9.25, P < .001 among the 11,870 patients with in-network surgeons). About 10.4% of patients with in-network surgeons were treated at out-of-network facilities.

CONCLUSION

Although the utilization of out-of-network facilities has decreased, over 10% of patients with in-network surgeons face out-of-network facility charges, which may often come as a surprise. Efforts are warranted to reduce the out-of-network facility burden for OP-TJA patients, including accelerating insurance contracting and reviewing patients' coverage statuses.

Amount of CMS Reduction in Facility Reimbursement Following Removal of Total Hip Arthroplasty From the Inpatient-Only List Far Exceeds Reduction in Actual Care Cost

BACKGROUND

Starting in 2020, Centers for Medicare and Medicaid Services (CMS) removed total hip arthroplasty (THA) from the inpatient-only list, resulting in an average of $1637 per case reduction in facility reimbursement. The purpose of this study is to determine whether the reduction in reimbursement is justified by comparing the difference in true facility costs between inpatient and outpatient THA.

METHODS

We identified a consecutive series of 5271 primary THA procedures from 2015 to 2019. Itemized procedural costs were calculated using a time-driven activity-based costing algorithm. Outpatient procedures were defined as those with less than a 24-hour length of stay. We compared patient demographics, comorbidities, and itemized costs between inpatient and outpatient procedures. A multivariate analysis was performed to determine the independent effect of outpatient status on true facility costs.

RESULTS

There were 783 (14.9%) outpatient THA procedures. The outpatient THA procedures incurred lower mean personnel ($1428 vs $2226, P < .001), supply ($4713 vs $4739, P < .001), and overall facility costs ($6141 vs $6595, P < .001) when compared with the same THA procedures done inpatient. When controlling for confounding variables, outpatient status was associated with a reduction in total facility costs of $825 (95% confidence interval, $734-$916, P < .001).

CONCLUSION

The reduction in CMS reimbursement far exceeds the $825 per-patient cost savings that can be achieved by a facility by performing THA as an outpatient. CMS should reconsider the Outpatient Prospective Payment System classification of THA to better incentivize surgeons to perform THA as a lower-cost outpatient procedure when safe and appropriate.

Defining Outpatient Hip and Knee Arthroplasties: A Systematic Review

INTRODUCTION

The term "outpatient" has a variety of meanings regarding the location of arthroplasty and the duration of stay postoperatively. The purpose of this systematic review was to evaluate the literature and more accurately define the term "outpatient."

METHODS

A PubMed search (2014 to 2019) using the terms "outpatient AND arthroplasty" identified 76 studies; 35 studies that met the inclusion criteria were assessed to determine the definition of "outpatient." The level of evidence, type of arthroplasty, location of surgery (hospital or ambulatory surgery center [ASC]), approach used for hip arthroplasty, number of patients, number of surgeons, and length of time the patients were kept at the location after surgery were evaluated.

RESULTS

Arthroplasties analyzed were total hip (11), total knee (seven), unicompartmental knee (five), and hip and knee (12). Only 16.8% of surgeries defined as outpatient hip or knee arthroplasty were done in a freestanding ASC, and 44.2% of patients defined as outpatients were kept overnight for the 23-hour observation.

DISCUSSION

We propose "DASH" (Discharge from ASC to Home) as a new term to define arthroplasties done in an outpatient setting with the patient discharged home the same day.

A Novel Machine Learning Predictive Tool Assessing Outpatient or Inpatient Designation for Medicare Patients Undergoing Total Hip Arthroplasty

Background

The Centers for Medicare and Medicaid Services removed total hip arthroplasty (THA) from the inpatient-only list. This has created significant confusion regarding which patients qualify for an inpatient designation. The purpose of this study is to develop and validate a novel predictive tool for preoperatively objectively determining “outpatient” vs “inpatient” status for THA in the Medicare population.

Methods

A cohort of Medicare patients undergoing primary THA between January 2017 and September 2019 was retrospectively reviewed. A machine learning model was trained using 80% of the THA patients, and the remaining 20% was used for testing the model performance in terms of accuracy and the average area under the receiver operating characteristic curve. Feature importance was obtained for each feature used in the model.

Results

One thousand ninety-one patients had outpatient stays, and 318 qualified for inpatient designation. Significant associations were demonstrated between inpatient designations and the following: higher BMI, increased patient age, better preoperative functional scores, higher American Society of Anesthesiologist Physical Status Classification, higher Modified Frailty Index, higher Charlson Comorbidity Index, female gender, and numerous comorbidities. The XGBoost model for predicting an inpatient or outpatient stay was 78.7% accurate with the area under the receiver operating characteristic curve to be 81.5%.

Conclusions

Using readily available key baseline characteristics, functional scores and comorbidities, this machine-learning model accurately predicts an “outpatient” or “inpatient” stay after THA in the Medicare population. BMI, age, functional scores, and American Society of Anesthesiologist Physical Status Classification had the highest influence on this predictive model.

Outcomes of Same-Day Orthopedic Surgery: Are Spine Patients More Likely to Have Optimal Immediate Recovery From Outpatient Procedures?

BACKGROUND

Spinal surgery is associated with an inherently elevated risk profile, and thus far there has been limited discussion about how these outpatient spine patients are benefiting from these same-day procedures against other typical outpatient orthopedic surgeries.

METHODS

Orthopedic patients who received either inpatient or outpatient surgery were isolated in the American College of Surgeons National Surgical Quality of Improvement Program (2005-2016). Patients were stratified by type of orthopedic surgery received (spine, knee, ankle, shoulder, or hip). Mean comparisons and chi-squared tests assessed basic demographics. Perioperative complications were analyzed via regression analyses in regard to their principal inpatient or outpatient orthopedic surgery received.

RESULTS

This study included 729 480 surgical patients: 32.5% received spinal surgery, 36.5% knee, 24.1% hip, 4.9% shoulder, and 1.7%ankle. Of those who received a spinal procedure, 74.7% were inpatients (IN), and 25.3% were outpatients (OUT): knee: 96.1% IN, 3.9% OUT; hip:98.9% IN, 1.1% OUT; ankle: 29% IN, 71% OUT; and shoulder: 52.6% IN, 47.6% OUT. Hip patients were the oldest, and knee patients had the highest body mass index out of the orthopedic groups (P < .00). Spine IN patients experienced more complications than the other orthopedic groups and had the lowest OUT complications(both P < .05). This same trend of having higher IN complications than OUT complications was identified for hip, shoulder, and knee. However, ankle procedures had greater OUT procedure complications than IN (P < .05). After controlling for age, body mass index, and Charlson Comorbidity Index, IN procedures, such as knee, hip, spine, and shoulder, were significantly associated with experiencing postoperative complications. From 2006 to 2016, IN and OUT surgeries were significantly different among complications experienced for all of the orthopedic groups (P < .05) with complications decreasing for IN and OUT patients by 2016.

CONCLUSIONS

Over the past decade, spine surgery has decreased in complications for IN and OUT procedures along with IN/OUT knee, ankle, hip, and shoulder procedures, reflecting greater tolerance for risk in an outpatient setting.

LEVEL OF EVIDENCE

3.

CLINICAL RELEVANCE

Despite the increase in riskier spine procedures, complications have decreased over the years. Surgeons should aim to continue to decrease inpatient spine complications to the level of other orthopedic surgeries.

Opioid Use Following Inpatient Versus Outpatient Total Joint Arthroplasty

BACKGROUND

Although the risks of continued opioid use following inpatient total joint arthroplasty (TJA) have been well-studied, these risks in the outpatient setting are not well known. The purpose of the present study was to characterize opioid use following outpatient compared with inpatient TJA.

METHODS

In this retrospective cohort study, opioid-naïve patients who underwent inpatient or outpatient (no overnight stay) primary, elective TJA from 2007 to 2017 were identified within a large national commercial-claims insurance database. For inclusion in the study, patients had to have been continuously enrolled in the database for ≥12 months prior to and ≥6 months after the TJA procedure. Multivariable analyses controlling for demographics, geography, procedure, year, and comorbidities were utilized to determine the association between surgical setting and risk of persistent opioid use, defined as the patient still filling new opioid prescriptions >90 days postoperatively.

RESULTS

We identified a total of 92,506 opioid-naïve TJA patients, of whom 57,183 (61.8%) underwent total knee arthroplasty (TKA). Overall, 7,342 patients (7.9%) underwent an outpatient TJA procedure, including 4,194 outpatient TKAs. Outpatient TJA was associated with reduced surgical opioid prescribing (78.9% compared with 87.6% for inpatient procedures; p < 0.001). Among the 80,393 patients (86.9%) who received surgical opioids, the total amount of opioids prescribed (in morphine milligram equivalents) was similar between inpatient (median, 750; interquartile range, 450 to 1,200) and outpatient procedures (median, 750; interquartile range, 450 to 1,140; p = 0.47); however, inpatient TJA patients were significantly more likely to still be taking opioids after 90 days postoperatively (11.4% compared with 9.0% for outpatient procedures; p < 0.001). These results persisted in adjusted analysis (adjusted odds ratio, 1.13; 95% confidence interval, 1.03 to 1.24; p = 0.01).

CONCLUSIONS

Outpatient TJA patients who received opioid prescriptions were prescribed a similar amount of opioids as those undergoing inpatient TJA procedures, but were significantly less likely to become persistent opioid users, even when controlling for patient factors. Outpatient TJA, as compared with inpatient TJA, does not appear to be a risk factor for new opioid dependence, and these findings support the continued transition to the outpatient-TJA model for lower-risk patients.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Risk Factors for Discharge to a Non-Home Destination and Reoperation Following Outpatient Total Hip Arthroplasty (THA) in Medicare-Eligible Patients

Introduction:

The Centers for Medicare and Medicaid Services removed total hip arthroplasty (THA) from the inpatient-only (IO) list in January 2020. Given this recommendation, we analyzed Medicare-eligible patients undergoing outpatient THA to understand risk factors for nonroutine discharge, reoperations, and readmissions.

Materials and Methods:

The 2015-2018 American College of Surgeons–National Surgical Quality Improvement Program database was queried using Current Procedural Terminology code 27130 for Medicare eligible patients (≥ 65 years of age) undergoing outpatient THA. Postoperative discharge destination was categorized into home and non-home. Multivariate logistic regression models were used to evaluate risk factors associated with non-home discharge disposition. Secondarily, we evaluated rates and risk factors associated with 30-day reoperations and readmissions.

Results:

A total of 1095 THAs were retrieved for final analysis. A total of 108 patients (9.9%) experienced a non-home discharge postoperatively. Patients were discharged to rehab (n = 47; 4.3%), a skilled care facility (n = 47; 4.3%), a facility that was “home” (n = 8; 0.7%), a separate acute care facility (n = 5; 0.5%), or an unskilled facility (n = 1; 0.1%). Independent factors for a non-home discharge were American Society of Anesthesiologists Class >II (odds ratio [OR] 2.74), operative time >80 minutes (OR 2.42), age >70 years (OR 2.20), and female gender (OR 1.67). Eighteen patients (1.6%) required an unplanned reoperation within 30 days. A total of 40 patients (3.7%) required 30-day readmissions, with 35 readmissions related to the original THA procedure. Independent risk factors for 30-day reoperation were COPD (OR 5.85) and HTN (OR 5.24). Independent risk factors for 30-day readmission were HTN (OR 4.35) and Age >70 (OR 2.48).

Discussion:

The current study identifies significant predictors associated with a non-home discharge, reoperation, and readmission in Medicare-aged patients undergoing outpatient THA.

Conclusion:

Providers should consider preoperatively risk-stratifying patients to reduce the costs associated with unplanned discharge destination, complication or reoperation.

"Outpatient"-Same-calendar-day Discharge Hip and Knee Arthroplasty

As the length of stay for hip and knee arthroplasty has decreased over the years, "outpatient," or same-calendar-day discharge has become increasingly common. Outpatient arthroplasty offers several possible benefits over traditional inpatient arthroplasty, including potential for cost reductions, faster rehabilitation, improved patient satisfaction, and reduced reliance on hospital resources. Despite these possible benefits, concerns remain over feasibility and patient safety. To date, multiple studies have demonstrated that, for select patients, "outpatient" hip and knee arthroplasty can be safe and effective and yield complication and readmission rates similar to inpatient procedures at potentially significant cost savings. Successful outpatient pathways have emphasized careful patient selection, detailed patient education, enlistment of strong social support, utilization of multimodal analgesia and strong "episode ownership," and involvement on behalf of the surgical team. As outpatient hip and knee arthroplasty becomes increasingly common, continued investigation into all aspects of the surgical episode is warranted.

More Predictable Return of Motor Function with Mepivacaine Versus Bupivacaine Spinal Anesthetic in Total Hip and Total Knee Arthroplasty: A Double-Blinded, Randomized Clinical Trial

BACKGROUND

Spinal anesthesia provides several benefits for patients undergoing total hip arthroplasty (THA) and total knee arthroplasty (TKA), but historically comes at the cost of slow and unpredictable return of lower-extremity motor function related to the use of long-acting local anesthetics. In this prospective, double-blinded, randomized clinical trial we sought to determine if an alternative local anesthetic, mepivacaine, would allow more consistent return of motor function compared with low-dose bupivacaine spinal anesthesia during primary THA and TKA.

METHODS

This trial was conducted at a single academic institution. Prior to trial initiation an internal pilot study determined that 154 patients were required to achieve 80% power. Patients were randomized in a 1:1 fashion with use of advanced computerized stratification based on procedure, age group, sex, and body mass index. Following the surgical procedure, motor function was assessed every 15 minutes in the nonoperative lower extremity according to the Bromage scale and discontinued once Bromage 0 was achieved (spontaneous movement at hip, knee, and ankle).

RESULTS

Return of lower-extremity function was more predictable in patients who received mepivacaine than in those who received low-dose bupivacaine. Among patients who received mepivacaine, 1% achieved motor function return beyond 5 hours compared with 11% of patients who received bupivacaine (p = 0.013). The mean time to return of lower-extremity motor function was 26 minutes quicker in patients who received mepivacaine (185 minutes; 95% confidence interval, 174 to 196 minutes) compared with low-dose bupivacaine (210 minutes; 95% confidence interval, 193 to 228 minutes) (p = 0.016). There were no significant differences in safety outcomes including pain scores, time to participation in physical therapy, incidence of orthostatic hypotension, urinary retention, or transient neurologic symptoms in patients receiving mepivacaine compared with low-dose bupivacaine.

CONCLUSIONS

In patients undergoing primary THA and TKA, spinal anesthesia with mepivacaine allowed more consistent return of lower-extremity motor function compared with low-dose bupivacaine, without a concomitant increase in complications potentially associated with spinal anesthetics. This is particularly of value in an era of short-stay and outpatient surgical procedures.

LEVEL OF EVIDENCE

Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Preoperative Predictors of Patients Requiring Inpatient Admission for Total Hip Arthroplasty Following Removal From the Medicare Inpatient-Only List

BACKGROUND

The Centers for Medicare and Medicaid Services has removed total hip arthroplasty from the inpatient-only (IO) list in January 2020. Given the confusion created when total knee arthroplasty came off the IO list in 2018, this study aims to develop a predictive model for guiding preoperative inpatient admission decisions based upon readily available patient demographic and comorbidity data.

METHODS

This is a retrospective review of 1415 patients undergoing elective unilateral primary THA between January 2018 and October 2019. Multiple logistic regression was used to develop a model for predicting LOS ≥2 days based on preoperative demographics and comorbidities.

RESULTS

Controlling for other demographics and comorbidities, increased age (odds ratio [OR], 1.048; P < .001), female gender (OR, 2.284; P < .001), chronic obstructive pulmonary disorder (OR, 2.249; P = .003), congestive heart failure (OR, 8.231; P < .001), and number of comorbidities (OR, 1.216; P < .001) were associated with LOS ≥2 days while patients with increased body mass index (OR, 0.964; P = .007) and primary hypertension (OR, 0.671; P = .008) demonstrated significantly reduced odds of staying in the hospital for 2 or more days. The area under the curve was found to be 0.731, indicating acceptable discriminatory value.

CONCLUSION

For patients undergoing primary THA, increased age, female gender, chronic obstructive pulmonary disorder, congestive heart failure, and multiple comorbidities are risk factors for inpatient hospital LOS of 2 or more days. Our predictive model based on readily available patient presentation and comorbidity characteristics may aid surgeons in preoperatively identifying patients requiring inpatient admission with removal of THA from the Medicare IO list.

Complications Following Total Hip Arthroplasty: A Nationwide Database Study Comparing Elective vs Hip Fracture Cases

BACKGROUND

The changing evaluation of provider metrics and payments in total hip arthroplasty (THA) necessitates current information for leaders in advocacy and policy. This study aims to use a contemporary nationwide cohort to compare and quantify the differences between the preoperative profile and clinical outcomes of THA performed for elective indications and for femoral neck fractures.

METHODS

Patient records from 2007 to 2017 were queried from an administrative claims database of privately insured patients comparing THA performed for femoral neck fractures vs elective indications. Ninety-day readmission rates as well as in-hospital and 90-day postdischarge rates of local and systemic complications were collected and compared with multivariate logistic regression.

RESULTS

Of 83,319 primary THAs, 6895 (8.3%) were fracture cases and 76,424 (91.7%) were elective. A greater proportion of fracture patients were older, female, not obese, and had a higher burden of comorbidities (all P < .001). Fracture patients had significantly higher average lengths of stay and complication rates for all perioperative and postoperative joint and systemic complications measured (all P < .001) as well as 90-day cost (32,228 vs 22,917 USD, P < .001).

CONCLUSION

Fracture patients are inherently more difficult cases to manage as surgeons. The results of these data may have significance in improving care coordination and provide evidence for further risk adjustment in payment models. Leaders in advocacy and policy should consider patient-level risk adjustments within alternative payment models to account for the increased association of complications, length of stay, readmission rate, and comorbidities in fracture patients receiving THA compared to elective patients.

Disparities in Hip Arthroplasty Outcomes: Results of a Statewide Hospital Registry From 2016 to 2018

BACKGROUND

In November 2019, Centers for Medicare and Medicaid Services announced total hip arthroplasty (THA) will be removed from the inpatient-only list. This may lead to avoidance of patients who have prolonged hospitalizations and discharge to skilled nursing facilities or push providers to unsafely push patients to outpatient surgery centers. Disparities in hip arthroplasty may worsen as patients are "risk stratified" preoperatively to minimize cost outliers. We aimed to evaluate which patient characteristics are associated with extended length of stay (eLOS)-greater than 2 days-and nonhome discharge in patients undergoing hip arthroplasty.

METHODS

The Illinois COMPdata administrative database was queried for THA admissions from January 2016 to June 2018. Variables included age, sex, race and ethnicity, median household income, Illinois region, insurance status, principal diagnosis, Charlson comorbidity index, obesity, discharge disposition, and LOS. Hospital characteristics included bundled payment participation and arthroplasty volume. Using multiple Poisson regression, we examined the association between these factors and the likelihood of nonhome discharge and eLOS.

RESULTS

There were 41,832 THA admissions from January 2016 to June 2018. A total of 36% had LOS greater than 2 midnights and 25.3% of patients had nonhome discharges. Female patients, non-Hispanic black patients, patients older than 75, obese patients, Medicaid or uninsured status, Charlson comorbidity index > 3, and hip arthroplasty for fracture were associated with increased risk of eLOS and/or nonhome discharge (P < .05).

CONCLUSION

With the Centers for Medicare and Medicaid Services emphasis on cost containment, patients at risk of extended stay or nonhome discharge may be deemed "high risk" and have difficulty accessing arthroplasty care. These are potentially vulnerable groups during the transition to the bundled payment model.

No Difference in Outcomes Between Short and Longer-Stay Total Joint Arthroplasty with a Discharge Home: A Propensity Score-Matched Analysis Involving 46,660 Patients

BACKGROUND

Outcomes following total hip arthroplasty (THA) and total knee arthroplasty (TKA) with a short length of hospital stay have been reported; however, most studies have not accounted for an inherent patient selection bias and discharge disposition. The purpose of this study was to utilize a propensity score to match and compare the outcomes of patients undergoing THA or TKA with short and longer lengths of stay with a discharge directly home.

METHODS

An administrative database from Ontario, Canada, which has a single-payer health-care system, was retrospectively reviewed to identify patients who underwent THA or TKA from 2008 to 2016. Patients were subsequently stratified into 2 groups based on their length of stay: short length of stay (≤2 days; thereafter referred to as short stay) and longer length of stay (>2 days; thereafter referred to as longer stay). Using a propensity score, patients who underwent short-stay THA or TKA were matched to patients who underwent longer-stay THA or TKA. Matching was based on 15 demographic, medical, and surgical factors. Our primary outcomes included postoperative complications, health-care utilization (readmission and emergency department presentation), and health-care costs.

RESULTS

Overall, 89,656 TKAs (14,645 short stays and 75,011 longer stays) and 52,610 THAs (9,426 short stays and 43,184 longer stays) were included in this study. Patients who underwent short-stay THA or TKA were significantly more likely (p < 0.05) to be younger, male, healthier, and from a higher socioeconomic status and to have undergone the procedure with a higher-volume surgeon. Over 95% of short-stay cases were successfully matched to longer-stay cases, and we found no significant difference in complications, health-care utilization, and costs between patients on the basis of the length of stay.

CONCLUSIONS

Patients undergoing short-stay THA or TKA with a discharge home were more likely to be younger, healthy, male patients from a higher socioeconomic status. Higher-volume surgeons are also more likely to perform short-stay THA or TKA. These characteristics confirm the previously held belief that a selection bias exists when comparing cohorts based on time to discharge. When comparing matched cohorts of patients who underwent short-stay and longer-stay THA or TKA, we observed no difference in outcomes, suggesting that a short stay with a discharge home in the appropriately selected patient is safe following THA or TKA.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

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

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 90-day 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.

Financial impact of removal of total knee arthroplasty from the inpatient-only list for a physician-owned BPCI program

Objective

Assessing financial effects of removal of TKA from CMS inpatient-only list on physician-owned bundles.

Methods

We determined whether Medicare TKAs remained inpatient, versus changed to observational. We used CMS data to determine savings. Direct costs associated with BPCI were calculated.

Results

7/28 TKAs (25.0%) had inpatient status changed to observational, excluding them from BPCI. Estimated savings losses were $24,332. Direct costs for administrating BPCI were $51,250. Had the rate of patients changed to observational been 50%, bundle savings from remaining patients would be less than direct costs.

Conclusion

Removing TKA from CMS inpatient-only list may have negative financial implications.