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

Total Hip Surgical Approach Efficiency Outside of Surgical Time in the Ambulatory Surgical Center

BACKGROUND

Rising demand for total hip arthroplasty (THA) in ambulatory surgery centers (ASCs) requires improved efficiency, considering varying surgical approach time requirements, to manage caseloads and ensure safe same-day discharge (SDD). This study examines care phase durations, SDD success and delays, and outcomes, including 90-day complication rates and 1-year patient-reported outcomes (PROs).

METHODS

A retrospective review of primary THA patients at a single ASC (January 2019 to January 2021) was conducted. Data on demographics, phase-of-care times, perioperative outcomes, 90-day complications, and PROs were stratified by surgical approach. Comparison was done using 2-tailed t-test and Fisher exact test. Stepwise regression controlled for age, gender, body mass index, assistive device use, class attendance, American Society of Anesthesia score, Charlson comorbidity index, and diagnosis.

RESULTS

Groups differed in age, BMI, assistive device use, class attendance, and preoperative Veterans Rand 12-Item Health Survey physical component scores. The direct anterior approach (DAA) and posterior approach (PA) cohorts showed significant differences in phase-of-care times, except for spinal-time, and total-physical therapy (PT)-time-in-postanesthesia care unit (PACU). DAA was faster in spinal-start-to-incision-time (26.8 versus 35.0; P < 0.001), set-up/take-down-time (20.5 versus 30.2; P < 0.001), operative time (OR; 37.5 versus 50.4; P < 0.001), total operating room time (57.8 versus 80.5; P < 0.001), and arrival-to-discharge-time (383.8 versus 418.4; P < 0.001). PA was faster in time-to-initiation-of-PT (46.3 versus 71.4; P < 0.001), PACU-arrival-to-PT-cleared-time (124.9 versus 144.3; P < 0.001), and total-PACU-time (127.8 versus 143.4; P < 0.001). Surgical approach, age, BMI, and preoperative assistive device use predicted time differences. Excessive spinal was the main cause of PT delays. No differences in 90-day complications or PROs were observed.

CONCLUSIONS

DAA showed shorter total OR and arrival-to-discharge-times compared to PA, with similar complications and PROs. Both approaches effectively achieved SDD. Operative and set-up/take-down-time drove DAA efficiency, but PT initiation was delayed due to standard spinal blocks with shorter OR times.

Same-Day Discharge Total Knee Arthroplasty: Hospital Demonstrates Similar Outcomes to Ambulatory Surgery Center in a More Complex Patient Population

BACKGROUND

The purpose of this study was to compare outcomes between patients undergoing same-day discharge (SDD) total knee arthroplasty (TKA) at an ambulatory surgery center (ASC) versus a tertiary care university hospital setting.

METHODS

A single tertiary academic center's institutional database was reviewed for patients who underwent primary TKA and were discharged the same day from August 2021 to January 2024. Patients who did not have at least 1 year of follow-up were excluded. Patient demographics, comorbidities, patient-reported outcome measures, emergency department visits, admissions, reoperations, and revisions were collected. Patients were stratified by the location of their surgery: ASC versus hospital. Specific criteria had to be met prior to surgery at the ASC, and the final decision regarding the location of surgery was made via shared decision-making between the patient and their surgeon. Patients who did not meet ASC criteria underwent TKA at the main hospital. Univariable analyses were used to compare groups, and multivariable logistic regression was used to determine if surgical location was a significant factor. Of the 449 TKAs meeting inclusion criteria, 63.3% (284) were performed at the ASC and 36.7% (165) at the university hospital at a mean follow-up of 1.51 years (range, 1.00 to 2.40). Of those 165 whose surgery was done at the hospital, 93.9% met at least one ASC exclusion criteria.

RESULTS

Patients whose TKA was done at the hospital had significantly higher weight (P = 0.003), body mass index (P < 0.001), Elixhauser comorbidity index (P < 0.001), proportion of patients who had an American Society of Anesthesiologists classification of 3 (P = 0.023), and proportion of patients who required general anesthesia (P < 0.001). Additionally, patients whose TKA was done at the hospital had higher preoperative patient-reported outcome measurement information system (PROMIS) pain interference (PI) (62.0 [59.0, 66.0] versus 63.0 [61.8, 67.0]; P = 0.006), and lower physical function (PF) (39.0 [36.0, 43.0] versus 38.0 [34.0, 41.0]; P = 0.001). At 1 year, however, patients in both groups had similar PROMIS PI (53.0 [49.0, 59.0] versus 54.0 [44.0, 59.0]; P = 0.785) and PROMIS PF (47.0 [42.0, 51.0] versus 47.0 [41.0, 50.0]; P = 0.422) scores as well as similar rates of achieving minimum clinically important difference for PROMIS PI (64.4 versus 71.4%; P = 0.336) and PROMIS PF (60.5 versus 71.4%; P = 0.124). They also had a similar number of emergency department visits and admissions at 30 and 90 days, as well as similar reoperation-free (92.0 versus 93.3%; P = 0.79) and revision-free (95.5 versus 99.4%; P = 0.59) survival at 2 years CONCLUSIONS: Although ASCs have strict patient criteria for SDD TKA, complex patients at a tertiary university hospital can be sent home the same day with equivalent outcomes. Therefore, unhealthier patients can safely achieve SDD without compromising outcomes if done in the appropriate setting.

Optimizing Operating Room Efficiency for Primary Hip and Knee Arthroplasty Using Performance Benchmarks

Background

With increasing demand for total hip arthroplasty (THA) and total knee arthroplasty (TKA), maximizing operating room (OR) efficiency is critical. This paper sought to examine the implementation of time benchmarks when performing primary TKA and THA. We hypothesized that implementing benchmarks would improve efficiency and the number of joints performed per day.

Methods

Two hundred ninety-five patients from 59 OR days were reviewed. All surgeries were performed as outpatients and included 160 females and 135 males; 161 TKA and 134 THA; mean age, 66.1; mean body mass index, 28.6 kg/m2; American Society of Anesthesia, 2. Time points, demographics, and adverse events were recorded. Benchmarks to complete 4 joints in 8 h were: anesthesia preparation time (APT) of <11 min, procedure time of <72 min, anesthesia finish time (AFT) of <21 min, and turnover of <22 min.

Results

The percentage of cases meeting individual benchmarks for APT was 50.17%; procedure time was 95.25%; AFT was 99.67%; turnover was 65.25%. The means were: APT 11:00 min, Surgical Prep Time 9:00 min, procedure time 55:00 min, AFT 3:00 min, and turnover 19:00 min. Overall, 98.3% (58/59) of ORs had 4 cases completed within 8 h and 52.5% (31/59) had 5 cases within 8 h. Age, body mass index, and consecutive laterality of surgery were determined to affect the likelihood of meeting benchmarks for case time, APT, and turnover.

Conclusions

Establishing time benchmarks permitted the introduction of 5 joint days within an 8-h OR without increasing resource utilization. Factors that influence OR efficiency for high-volume primary hip and knee replacements were identified.

Outpatient Total Joint Arthroplasty in the "Unhealthy": Staying Safe Using Institutional Protocols

BACKGROUND

Recent expansion in the indications for outpatient total joint arthroplasty has led to debates over patient selection. The purpose of this study was to compare early clinical outcomes and complications of same-day discharge (SDD) hip and knee arthroplasties from a high-volume institution based on the American Society of Anesthesiologists (ASA) physical status classification.

METHODS

Prospectively collected data were reviewed for all SDD primary joint arthroplasties between January 2013 and August 2023. There were 8 surgeons who performed 7,258 cases at hospital outpatient (n = 4,288) or ambulatory surgery centers (n = 2,970). This included 3,239 total hip arthroplasties, 1,503 total knee arthroplasties, and 2,516 unicompartmental knee arthroplasties. The ASA 1 group comprised 506 subjects, compared to 5,005 for ASA 2 and 1,736 for ASA 3. The primary outcomes included emergency department (ED) visits, readmissions, complications, and revisions within 24 hours and 90 days of surgery. The ASA 3 group was older (ASA 1 = 55 versus ASA 2 = 63 versus ASA 3 = 66 years; P < .01) and had a higher body mass index (ASA 1 = 25.4 versus ASA 2 = 28.5 versus ASA 3 = 32.7; P < .01).

RESULTS

There were no differences between ASA groups in joint-related ED visits, readmissions, and complications within 24 h and 90 days of surgery (P > .05). Subjects in the ASA 3 group experienced greater 90-day revisions compared to the other groups (ASA 1 = 1 of 506, 0.2% versus ASA 2 = 15 of 5,005, 0.3% versus ASA 3 = 15 of 1,736, 0.9%; P = .01). Regarding systemic events, ASA 1 subjects experienced significantly greater 24-hour complications (8 of 506, 1.6%) and ED visits (5 of 506, 1.0%), and the ASA 3 subjects had a higher incidence of 90-day readmissions (19 of 1,736, 1.1%) compared to the other groups (P < .05). Within 24 hours of discharge, urinary retention and syncope were the most frequent complications that required additional health care utilization.

CONCLUSIONS

Medically optimized patients categorized as ASA 3 can safely undergo SDD hip and knee arthroplasty without increased risk of 24-hour or 90-day complications. Patient preference for outpatient care, reliable social support, and independent functional status are imperative for a successful outpatient program.

The Financial Burden of Patient Comorbidities on Total Knee Arthroplasty Procedures: A Matched Cohort Analysis of Patients Who Have a High and Non-High Comorbidity Burden

BACKGROUND

Recent literature suggests a trend toward a higher comorbidity burden in patients undergoing total knee arthroplasty (TKA). However, the impact of increased comorbidities on the cost-effectiveness of TKA is underexplored. This study aimed to compare the financial implications and perioperative outcomes of patients with and without a high comorbidity burden (HCB).

METHODS

We retrospectively reviewed 10,647 patients who underwent elective, unilateral TKA between 2012 and 2021 at a single academic health center with available financial data. Patients were stratified into HCB (Charlson Comorbidity Index ≥ 5 and American Society of Anesthesiology scores of 3 or 4) and non-HCB groups. A 1:1 propensity match was performed based on baseline characteristics, resulting in 1,536 matched patients (768 per group). Revenue, costs, and contribution margins (CM) of the inpatient episode were compared between groups. Ninety-day readmissions and revisions were also analyzed.

RESULTS

The HCB patients had significantly higher total (P < 0.001) and direct (P < 0.001) costs, while hospital revenue did not differ between cohorts (P = 0.638). This disparity resulted in a significantly decreased CM for the HCB group (P = 0.009). Additionally, HCB patients had a longer length of stay (P < 0.001) and a higher rate of 90-day readmissions (P = 0.005).

CONCLUSIONS

Increased inpatient costs for HCB patients undergoing TKA were not offset by proportional revenue, leading to a decreased CM. Furthermore, higher 90-day readmissions exacerbate the financial burden. These findings highlight potential challenges for hospitals in covering indirect expenses, which could jeopardize accessibility to care for HCB patients. Reimbursement models should be revised to better account for the increased financial burden associated with managing HCB patients.

LEVEL OF EVIDENCE

III.

Simultaneous Versus Staged Bilateral Total Hip Arthroplasty: A Matched Cohort Analysis of Revenue and Contribution Margin

BACKGROUND

Though previous studies have demonstrated improved cost benefits associated with simultaneous versus staged bilateral total hip arthroplasty (simBTHA and staBTHA), further investigation is needed regarding the revenues and contribution margins (CMs) of these procedures. In this study, we compared revenue, CM, and surgical outcomes between simBTHA and staBTHA.

METHODS

All patients who underwent simBTHA (both procedures completed the same day) and staBTHA (procedures completed on different days within one year) between 2011 and 2021 at a single high-volume orthopedic specialty hospital were identified. Of the 1,517 identified patients (n = 139 simBTHA, n = 1,378 staBTHA), 232 were included in a 1:1 propensity match based on baseline demographics (116 per cohort). Revenue, costs, CM, and surgical outcomes were compared between cohorts.

RESULTS

Compared to staBTHA, simBTHA procedures had significantly lower total costs (P < .001), direct costs (P < .001), and patient revenue. There was no significant difference in CM between groups (P = .361). Additionally, there were no significant differences in length of stay (P = .173), operative time (P = .438), 90-day readmissions (P = .701), 90-day revisions (P = .313), or all-cause revisions (P = .701) between cohorts.

CONCLUSIONS

Though simBTHA procedures have lower revenues than staBTHA, they also have lower costs, resulting in similar CM between procedures. As both procedures have similar postoperative complication rates, further research is required to evaluate specifically which patients may benefit from simBTHA versus staBTHA regarding clinical and patient-reported outcomes.

LEVEL OF EVIDENCE

III.

Is It Getting More Expensive to Treat Patients Who Have a High Comorbidity Burden? Financial Trends in Total Knee Arthroplasty From 2013 to 2021

BACKGROUND

Utilization of total knee arthroplasty (TKA) continues to rise among patients who have a high comorbidity burden (HCB). With changes in reimbursement models over the past decade, it is essential to assess the financial impact of HCB TKA on healthcare systems. This study aimed to examine trends in revenue and costs associated with TKA in HCB patients over time.

METHODS

Of 14,978 TKA performed at a large, urban academic medical center between 2013 and 2021, we retrospectively analyzed HCB patients (Charlson comorbidity index ≥ 5 and American Society of Anesthesiology scores of 3 or 4). A total of 1,156 HCB TKA patients who had complete financial data were identified. Patient demographics, perioperative data, revenue, costs, and contribution margin were collected for each patient. Changes in these financial values over time, as a percentage of 2013 values, were analyzed. Linear regression was performed with a trend analysis to determine significance.

RESULTS

From 2013 to 2021, the percentage of HCB TKAs per year increased from 4.2% in 2013 to 16.5% in 2021 (P < .001). The revenue of TKA in HCB patients remained steady (P = .093), while direct costs increased significantly (32.0%; P = .015), resulting in a decline of contribution margin to a low of 82.3% of 2013 margins. There was no significant change in rates of 90-day complications or home discharge following HCB TKA during the study period.

CONCLUSIONS

The results of this study indicate a major rise in cost for TKA among HCB patients, without a corresponding rise in revenue. As more patients who have HCB become candidates for TKA, the negative financial impact on institutions should be considered, as payments to institutions do not adequately reflect patient complexity. A re-evaluation of institutional payments for medically complex TKA patients is warranted to maintain patient access among at-need populations.

The Financial Feasibility of Bilateral Total Knee Arthroplasty: A Matched Cohort Analyses of Revenue and Contribution Margin Between Simultaneous and Staged Procedures

BACKGROUND

Financial analyses of simultaneous bilateral total knee arthroplasty versus staged bilateral total knee arthroplasty (simBTKA and staBTKA, respectively) have shown improved cost-effectiveness of simBTKA, though revenue and contribution margin (CM) for these procedures have not been investigated. Our analyses compared surgical outcomes, revenues, and CMs between simBTKA and staBTKA.

METHODS

We retrospectively reviewed all patients who underwent simBTKA (both procedures done on the same day) and staBTKA (procedures done on a different day within one year) between 2012 and 2021. Patients were 1:1 propensity matched based on baseline characteristics. Surgical outcomes, as well as revenue, cost, and CM of the inpatient episode were compared between groups. Of the 2,357 patients evaluated (n = 595 simBTKA, n = 1,762 staBTKA), 410 were included in final matched analyses (205 per group).

RESULTS

Total (P < .001) and direct (P < .001) costs were significantly lower for simBTKA procedures compared to overall costs of both staBTKA procedures. Significantly lower revenue for simBTKA procedures (P < .001), resulted in comparable CM between groups (P = .477). Postoperative complications including 90-day readmission (P = 1.000), 90-day revision (P = 1.000) and all-cause revision at latest follow-up (P = .083) were similar between groups.

CONCLUSIONS

In our propensity-matched cohort, lower costs for simBTKA compared to staBTKA were matched by lower revenues, with a resulting similar CM between procedures. Given that postoperative complication rates were similar, both procedures had comparable cost-effectiveness. Future research is needed to identify patients for whom simBTKA may represent a better surgical intervention compared to staBTKA with respect to clinical and patient reported outcomes.

Growing utilization of ambulatory spine surgery in Medicare patients from 2010-2021

Background

There is growing interest in transitioning various surgical procedures to the outpatient care setting. However, for Medicare patients, the site of service for surgical procedures is influenced by regulations within the Inpatient and Outpatient Prospective Payment Systems. The purpose of this study is to quantify changes in utilization of outpatient spine surgery within the Medicare population, as well as to determine changes in outpatient volume after removal of a procedure from the "inpatient-only" list.

Methods

This is a cross-sectional study of Medicare billing database information for selected spine procedures included in the Medicare Physician/Supplier Procedure Summary (PSPS) public use files from 2010-2021. These files include aggregated data from Medicare Part B fee-for-service claims, published yearly. Procedures from Healthcare Common Procedural Coding System (HCPCS) code ranges 22010-22899 and 62380-63103 were selected for analysis, limited to surgical services delivered in the inpatient, hospital outpatient department (HOPD), and ambulatory surgical center (ASC) settings. For each HCPCS code included, estimates of the total number of services and corresponding changes in volume were calculated.

Results

Within the range of codes included in the study, the total number of outpatient spine procedures rose approximately 193% from 2010 to 2021, with compound annual growth rate (CAGR) for outpatient procedures per year of 9.9% for HOPDs and 15.7% for ASCs (-2.2% for inpatient procedures). Within this period, the ASC list grew from 12 procedures to 58 procedures. In 2021, the highest volume ASC procedure was HCPCS 63047, at approximately 4970 procedures.

Conclusions

This study demonstrates a trend of increasing utilization of HOPDs and ASCs for spine procedures among Medicare beneficiaries from 2010 to 2021. Though HOPDs are currently more widely utilized, the ongoing additions of spine procedures to the ASC covered procedures list may shift this balance.

The Effect of Surgical Approach on the Outcomes of Same-Day Discharge Outpatient Total Hip Arthroplasty at a Single Ambulatory Surgery Center

BACKGROUND

Primary total hip arthroplasty (THA) is increasingly being performed in the outpatient setting. However, there is little known regarding the differences in same-day discharge (SDD) rates and complications of operative approach in same-day total hip arthroplasty in the ambulatory surgery center (ASC) setting.

METHODS

A retrospective chart review was performed between July 2019 and October 2021 for all patients who underwent primary THA in a single freestanding ASC. Successful SDDs, surgical approaches, lengths of surgery, estimated blood losses (EBL), complications, and readmission events were recorded for each patient. Complications were compared using Pearson Chi-Squares, while EBL and surgery lengths were compared with 1-way analysis of variances (ANOVA) (alpha = 0.5). There were 17 total complications in 326 total hip arthroplasties (5.2%), including direct admissions to the emergency department, 30-day and 90-day readmissions, wound complications, instability, infection, and revision surgery. Among all complications, there were 5 direct admissions, making the successful SDD rate 98.5%.

RESULTS

Complications and direct admissions were not associated with approach. The 30-day readmission rates were associated with approach, with no readmissions in the direct anterior approach (DAA) or the antero-lateral approach (AL) cohorts and 3 (4.3%) in the posterior approach (PA) cohort.

CONCLUSIONS

In the ASC setting, patients undergoing THA regardless of approach showed no difference in successful SDDs or complications aside from 30-day readmissions. Same-day THA can be safely performed in the DAA, AL, and PA to the hip.