Has Removal From the Inpatient-Only List Increased Complications After Outpatient Total Knee Arthroplasty?

Site of Service Disparities Exist for Total Joint Arthroplasty

BACKGROUND

The rate of outpatient total joint arthroplasty procedures, including those performed at ambulatory surgical centers (ASCs) and hospital outpatient departments, is increasing. The purpose of this study was to analyze if type of insurance is associated with site of service (in-patient vs outpatient) for total joint arthroplasty and adverse outcomes.

MATERIALS AND METHODS

We identified patients undergoing unicompartmental knee arthroplasty (UKA), total knee arthroplasty (TKA), or total hip arthroplasty (THA) using Current Procedural Terminology codes in a national administrative claims database. Eligible patients were stratified by type of insurance (Medicaid, Medicare, private). The primary outcome was site of service. Secondary outcomes included general complications, procedural complications, and revision procedures. We evaluated the associations using adjusted multivariable logistic regression models.

RESULTS

We identified 951,568 patients for analysis; 46,703 (4.9%) patients underwent UKA, 607,221 (63.8%) underwent TKA, and 297,644 (31.3%) underwent THA. Overall, 9.6% of procedures were outpatient. Patients with Medicaid were less likely than privately insured patients to receive outpatient UKA or THA (UKA: odds ratio [OR], 0.729 [95% CI, 0.640-0.829]; THA: OR, 0.625 [95% CI, 0.557-0.702]) but more likely than patients with Medicare to receive outpatient TKA or THA (TKA: OR, 1.391 [95% CI, 1.315-1.472]; THA: OR, 1.327 [95% CI, 1.166-1.506]). Patients with Medicaid were more likely to experience complications and revision procedures.

CONCLUSION

Differences in site of service and complication rates following hip and knee arthroplasty exist based on type of insurance, suggesting a disparity in care. Further exploration of drivers of this disparity is warranted and can inform interventions (eg, progressive value-based payments) to support equity in orthopedic services. [Orthopedics. 2024;47(3):179-184.].

The Removal of Total Knee Arthroplasty From the Inpatient-Only List has Improved Patient Optimization

INTRODUCTION

On January 1, 2018, the Centers for Medicare and Medicaid Services removed total knee arthroplasty (TKA) from the inpatient-only (IPO) list, expanding outpatient TKA (oTKA) to include patients with insurance coverage through their programs. These regulatory changes reinforced the need for preoperative optimization to ensure a safe and timely discharge after surgery. This study compared modifiable preoperative optimization metrics in patients who underwent oTKA pre-IPO and post-IPO removal. The authors hypothesized that patients post-IPO removal would demonstrate improvement in the selected categories.

METHODS

Outpatient TKA in a national database was identified and stratified by surgical year (2015 to 2017 versus 2018 to 2020). Preoperative optimization thresholds were established for the following modifiable risk factors: albumin, hematocrit, sodium, smoking, and body mass index. The percentage of patients who did not meet thresholds pre-IPO and post-IPO removal were compared.

RESULTS

In total, 2,074 patients underwent oTKA from 2015 to 2017 compared with 46,480 from 2018 to 2020. Patients undergoing oTKA after IPO removal were significantly older (67.0 versus 64.4 years; P < 0.01). A lower percentage of patients in the post-IPO cohort fell outside the threshold for all modifiable risk factors. Results were significant for preoperative sodium (10.7% versus 8.8%; P < 0.01), body mass index (12.4% versus 11.0% P = 0.05), and smoking history (9.9% versus 6.6%; P < 0.01).

CONCLUSION

Outpatient TKA has increased considerably post-IPO removal. As this regulatory change has allowed older patients with increased comorbidities to undergo oTKA, the need for appropriate preoperative optimization has increased. The current data set demonstrates that surgeons have improved preoperative optimization efforts for select modifiable risk factors.

Real-World Evidence of the Impact of a Novel Surgical Irrigant on Surgical Site Infections in Primary Total Knee Arthroplasty Performed at an Ambulatory Surgery Center

Background: Total knee arthroplasty (TKA) is one of the most common inpatient and outpatient surgical procedures performed in the United States and is predicted to increase 401% by 2040. Surgical site infections (SSIs) at an incidence rate of approximately 2% are costly post-operative complications in TKA. Intra-operative surgical irrigants are used to decrease contaminating microbial bioburden within the surgical site to prevent SSI. The primary objective of this retrospective study was to evaluate the impact of a novel surgical irrigant called XPERIENCE® Advanced Surgical Irrigation (XP; Next Science, Jacksonville, FL) on SSI incidence in primary TKA performed at an ambulatory surgery center (ASC). Patients and Methods: Primary TKAs were performed at a free-standing ASC. The novel surgical irrigant was used intra-operatively to rinse away debris and micro-organisms from the surgical site. Retrospective data collation included SSI rates, complication rates, and re-admissions due to SSI within 90 days of index surgery. Results: Among the 524 primary TKA surgeries, one peri-prosthetic joint infection (PJI) was diagnosed within 90 days of index surgery and one superficial incisional SSI was diagnosed within 30 days of index surgery. The PJI was attributed to an exogenously acquired upper respiratory tract infection rather than due to the failure of intra-operative regimes. The 0.19% PJI incidence rate indicated significant efficacy of XP in decreasing PJI. An overall complication rate of 7.82% was noted with none of the complications associated with usage of the novel surgical irrigant. Conclusions: XPERIENCE is a promising intra-operative antimicrobial irrigant that can be easily incorporated into a broader infection prevention strategy.

Outpatient Total Knee Arthroplasty From a Stand-Alone Surgery Center: Safe as the Hospital?

BACKGROUND

Literature suggests that outpatient arthroplasty may result in low rates of complications and readmissions. There is, however, a dearth of information on the relative safety of total knee arthroplasty (TKA) performed at stand-alone ambulatory surgery centers (ASCs) versus hospital outpatient (HOP) settings. We aimed to compare safety profiles and 90-day adverse events of these 2 cohorts.

METHODS

Prospectively collected data were reviewed on all patients who underwent outpatient TKA from 2015 to 2022. The ASC and HOP groups were compared, and differences in demographics, complications, reoperations, revisions, readmissions, and emergency department (ED) visits within 90 days of surgery were analyzed. There were 4 surgeons who performed 4,307 TKAs during the study period, including 740 outpatient cases (ASC = 157; HOP = 583). The ASC patients were younger than HOP patients (ASC = 61 versus HOP = 65; P < .001). Body mass index and sex did not differ significantly between groups.

RESULTS

Within 90 days, 44 (6%) complications occurred. No differences were observed between groups in rates of 90-day complications (ASC = 9 of 157, 5.7% versus HOP = 35 of 583, 6.0%; P = .899), reoperations (ASC = 2 of 157, 1.3% versus HOP = 3 of 583, 0.5%; P = .303), revisions (ASC = 0 of 157 versus HOP = 3 of 583, 0.5%; P = 1), readmissions (ASC = 3 of 157, 1.9% versus HOP = 8 of 583, 1.4%; P = .625), and ED visits (ASC = 1 of 157, 0.6% versus HOP = 3 of 583, 0.5%; P = .853).

CONCLUSION

These results suggest that in appropriately selected patients, outpatient TKA can be safely performed in both ASC and HOP settings with similar low rates of 90-day complications, reoperations, revisions, readmissions, and ED visits.

Inpatient vs outpatient arthroplasty: A in-state database analysis of 90-day complications

Introduction

An increase in the number of policy initiatives, such as alternative payment models, have prompted healthcare providers to examine health-care expenditures while seeking to improve quality of care. Performing total joint arthroplasty (TJA) in the outpatient setting is an attractive option in driving costs down and providing psychological benefits to patients. Concerns regarding the safety and effectiveness of same-day discharge protocols warrants further investigation, especially on the state level. Due to the lack of consensus, we aimed to compare: (1) risk factors for outpatient arthroplasty and (2) incidences of postoperative complications between inpatient vs outpatient arthroplasty using an in-state database.

Methods

Patients who underwent total knee or hip arthroplasty between January 1, 2022 and December 31, 2022 were identified. Data was drawn from the Maryland State Inpatient Database (SID) and Maryland State Ambulatory Surgery and Services Database (SASD). A total of 7817 patients had TJA within this time. Patients were divided into inpatient arthroplasty (n = 1429) and outpatient arthroplasty (n = 6338). Demographic variables, medical comorbidities, and 90-day complication rates were compared between inpatient and outpatient procedures. Additional independent variables included: marital status, primary language, race, and median household income. A multivariate logistic regression analysis was performed to identify independent risk factors for complications following TJA after controlling for risk factors and patient comorbidities.

Results

Arthroplasty in the outpatient setting were more likely to be married (61.3% vs. 51.2%, p < 0.001), white (75.5% vs. 60.9%, <0.001), speak English as primary language (98.7% vs. 88.6%, p < 0.001), and have lower rates of diabetes (4.8% vs. 9.7%, p < 0.001), chronic obstructive pulmonary disease (16.3% vs. 21.8%, p < 0.001), and obesity (30.0% vs. 45.2%, p < 0.001) compared to arthroplasty in the inpatient setting, respectively. There were lower incidences of acute kidney injury (0.2 vs. 0.8%, p < 0.001) and infection (0.3% vs. 1.1%, p < 0.001) in the outpatient cohort compared to the inpatient cohort, respectively. Inpatient arthroplasty (Odds Ratio (OR) 1.98, 95% CI 1.30-3.02, p = 0.002) and hypertension (OR 2.12, 95% CI 1.23-3.64, p = 0.007) were independent risk factors for total complications following TJA.

Conclusion

Arthroplasty in the outpatient setting showed fewer complications than compared to patients in the inpatient setting. Although multiple factors should guide the decision for arthroplasty, outpatient arthroplasty may be a safe option for select, healthier patients without the increased burden of increased complications.

Patient Designation Prior to Total Knee Arthroplasty: How Can Preoperative Variables Impact Postoperative Status?

BACKGROUND

Removal of total knee arthroplasty (TKA) from the inpatient only list has led to a greater focus on outpatient (OP) procedures. However, the impact of OP-centered models in at-risk patients is unclear. Therefore, the current analysis investigated the effect of conversion from OP to inpatient (IP) status on postoperative outcomes and determined which factors put patients at risk for status change postoperatively.

METHODS

We retrospectively reviewed all patients who underwent a primary TKA at our institution between January 2, 2018, and April 26, 2022. All patients included were originally scheduled for OP surgery and were separated based on conversion to IP status postoperatively. Multiple regression analyses were used to determine the significance of all perioperative variables. Modeling via binary logistic regressions was used to determine factors predictive of status conversion.

RESULTS

Of the 2,313 patients originally designated for OP TKA, 627 (27.1%) required a stay of 2 midnights or longer. Patients in the IP group had significantly higher facility discharge rates (P < .001) compared to the OP group. Factors predictive of conversion included age of 65 years and older (P < .001), women (P < .001), arriving at the postanesthesia care unit after 12 pm (P < .001), body mass index greater than 30 (P = .004), and Charlson Comorbidity Index of 4 and higher (P = .004). Being the first case of the day (P < .001) and being married (P < .001) were both protective against conversion.

CONCLUSION

Certain intrinsic patient factors may predispose a patient to an IP stay, and an understanding of predisposing factors which could lead to IP conversion may improve perioperative planning moving forward.

Robotic-Assisted Total Knee Arthroplasty is Safe in the Ambulatory Surgery Center Setting

BACKGROUND

Robotic-assisted total knee arthroplasty (RA-TKA) has become more popular in the United States. With the significant trend towards performing TKA in outpatient and ambulatory surgery center (ASC) settings, this study was implemented to determine the safety and efficacy of RA-TKA in an ASC.

METHOD

A retrospective review identified 172 outpatient TKAs (86 RA-TKAs and 86 TKAs) performed between January 2020 and January 2021. All surgeries were performed by the same surgeon at the same free-standing ASC. Patients were followed for at least 90 days after surgery; complications, reoperations, readmissions, operative time, and patient-reported outcomes were recorded.

RESULTS

In both groups, all patients were successfully discharged home from the ASC on the day of surgery. No differences were noted in overall complications, reoperations, hospital admissions, or delays in discharge. RA-TKA had slightly longer operative times (79 vs 75 min [p = 0.017]) and total length of stay at the ASC (468 vs 412 min [p < 0.0001]) than conventional TKA. No significant differences were noted in outcome scores at 2-, 6-, or 12-week follow-ups.

CONCLUSIONS

Our results showed that RA-TKA can be successfully implemented in an ASC, with similar outcomes compared with TKA using conventional instrumentation. Initial surgical times were increased secondary to the learning curve of implementing RA-TKA. Long-term follow-up is necessary to determine implant longevity and long-term outcomes.

METHOD

A retrospective review identified 172 outpatient TKAs (86 RA-TKAs and 86 TKAs) performed between January 2020 and January 2021. All surgeries were performed by the same surgeon at the same free-standing ASC. Patients were followed for at least 90 days after surgery; complications, reoperations, readmissions, operative time, and patient-reported outcomes were recorded.

RESULTS

In both groups, all patients were successfully discharged home from the ASC on the day of surgery. No differences were noted in overall complications, reoperations, hospital admissions, or delays in discharge. RA-TKA had slightly longer operative times (79 vs 75 min [p = 0.017]) and total length of stay at the ASC (468 vs 412 min [p < 0.0001]) than conventional TKA. No significant differences were noted in outcome scores at 2-, 6-, or 12-week follow-ups.

CONCLUSIONS

Our results showed that RA-TKA can be successfully implemented in an ASC, with similar outcomes compared with TKA using conventional instrumentation. Initial surgical times were increased secondary to the learning curve of implementing RA-TKA. Long-term follow-up is necessary to determine implant longevity and long-term outcomes.

The removal of total hip arthroplasty from the inpatient-only list has improved patient selection and expanded optimization efforts

INTRODUCTION

On January 1, 2020, the Centers for Medicare and Medicaid Services removed total hip arthroplasty (THA) from the Inpatient-Only (IPO) list. This study evaluated patient demographics and comorbidities, pre-operative optimization efforts, and 30-day outcomes of patients undergoing outpatient THA pre- and post- IPO-removal. The authors hypothesized that patients undergoing THA post-IPO removal would have improved optimization of modifiable risk factors and equivalent 30-day outcomes.

METHODS

There were 17,063 outpatient THA in a national database stratified by surgery performed pre- (2015 to 2019: 5,239 patients) and post-IPO (2020: 11,824 patients) removal. Demographics, comorbidities, and 30-day outcomes were compared with univariable and multivariable analyses. Pre-operative optimization thresholds were established for the following modifiable risk factors: albumin, creatinine, hematocrit, smoking history, and body mass index. The percentage of patients who fell outside the thresholds in each cohort were compared.

RESULTS

Patients undergoing outpatient THA post-IPO removal were significantly older; mean age 65 years (range, 18 to 92) vs 62 (range, 18 to 90) years (P<0.01), with a higher percentage of American Society of Anesthesiologists scores 3 and 4 (P<0.01). There was no difference in 30-day readmissions (P=0.57) or reoperations (P=1.00). A significantly lower percentage of patients fell outside the established threshold for albumin (P<0.01) post-IPO removal, and trended towards lower percentages for hematocrit and smoking status.

CONCLUSION

The removal of THA from the IPO list expanded patient selection for outpatient arthroplasty. Pre-operative optimization is critical to minimize post-operative complications, and the current study demonstrates that 30-day outcomes have not worsened post-IPO removal.

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.

Total Joint Arthroplasty at a Novel “Hyperspecialty” Ambulatory Surgical Center With Extended Care Suites is as Safe as Inpatient Arthroplasty

Background

New “hyperspecialty” ambulatory surgical centers (HASCs) have been introduced to deliver safe and cost-efficient care, allowing patients to spend additional nights in an extended care suite before discharge. This study compared the 90-day complications and readmissions of total joint arthroplasty (TJA) at an HASC and inpatient TJA at a tertiary hospital.

Methods

We retrospectively reviewed 1365 primary, unilateral, TJAs (658 total hip arthroplasty, 707 total knee arthroplasty) performed at 4 HASCs in 2017-2021. Following their outpatient procedure, patients were discharged to an extended care suite staffed full-time by nurses and physical therapists. These patients were matched 1:1 with 1365 inpatient TJAs (628 total hip arthroplasty, 737 total knee arthroplasty) based on demographics, joint, and American Society of Anesthesiologists (ASA) score. Ninety-day complications and readmissions were compared.

Results

The mean age was 60.0 ± 9.8 years and 59.4 ± 8.1 years in the inpatient and outpatient groups, respectively (P = .106). There was no difference in ASA≥3 patients (16.4% vs 17.7%; P = .387) and operative time (86.9 ± 31.8 vs 88.7 ± 27.9 minutes; P = .118). Five patients (0.4%) in the outpatient group were transferred to an acute hospital. When comparing 90-day outcomes between the inpatient and outpatient groups, there was no difference in pulmonary embolism (0.1% vs 0.0%; P = .317), mechanical complications (0.3% vs 0.7%; P = .165), periprosthetic joint infections (0.5% vs 1.1%; P = .092), or readmissions (1.2% vs 1.5%; P = .513). A subgroup analysis of ASA≥3 patients yielded similar findings.

Conclusions

Patients undergoing outpatient TJA at a novel HASC had similar complication and readmission rates as those undergoing TJA at a tertiary hospital. Based on these data, such facilities seem appropriate for the care of outpatient TJA patients with ASA<4.