Optimizing Patient Outcomes Following Orthopedic Surgery: The Role of Albumin and the Case For Fast- Track

Optimizing Patient Outcomes Following Orthopedic Surgery: The Role of Albumin and the Case For Fast- Track Andrew Ng Robin Wang Mentor: Atul Kamath, MD

Outline - The Role of Albumin as a Risk Factor for Patient Outcomes in Orthopedic Surgery - Background - Aims and Significance - Methods - Results - Conclusions - Optimizing Fast-Track Pathways: Identifying Key Patient-Level and Surgery-Level Predictors - Background - Aims and Significance - Methods

Background - Risk factors for hospital readmissions - Age, BMI, hemoglobin, GFR, albumin (Ellsworth et al, 2016) - Albumin - Standard clinical definitions Blood vessel Lymph fluid Hypoalbuminemia Normal Albumin Hyperalbuminemia 3.5 g/dl 5.0 g/dl - Marker for malnourishment - Immunocompromised patients (Bohl et al, 2016 & Courtney et al, 2015) Albumin Picture source: http://medifitbiologicals.com/vasodilators/

Background - Hip/Knee Arthroplasty - Joint Replacement/Reconstruction - 2 Types - Primary - Revision Picture source: https://crouse.org/health/hie%20multimedia/1/002975.html

- Aim - Identify the relationship between serum albumin and cost of treatment for hip or knee arthroplasties - Significance - Albumin has been correlated with higher rates of hospital readmissions due to perioperative complications (Walls et al, 2015 & Merkow et al, 2015) - Albumin linked to longer hospital stays (Bohl et al, 2016) - Lack of literature evaluating overall treatment cost Why study albumin?

Why study albumin? - Aim - Identify the relationship between serum albumin and cost of treatment for hip or knee arthroplasties - Significance - Albumin has been correlated with higher rates of hospital readmissions due to perioperative complications (Walls et al, 2015 & Merkow et al, 2015) - Albumin linked to longer hospital stays (Bohl et al, 2016) - Lack of literature evaluating overall treatment cost 7x risk

Why study albumin? - Aim - Identify the relationship between serum albumin and cost of treatment for hip or knee arthroplasties - Significance - Albumin has been correlated with higher rates of hospital readmissions due to perioperative complications (Walls et al, 2015 & Merkow et al, 2015) - Albumin linked to longer hospital stays (Bohl et al, 2016) - Lack of literature evaluating overall treatment cost 7x risk 0.42 days

- Orthopedic Patient Data Obtained From UPHS Orthopedic Department - January, 2014-December, 2016-83 variables collected, 4763 total patients - Excluded Data - 978 total observations dropped - Albumin data missing (845) - Other missing variable data (98) - Outpatient data (28) - Procedures other than arthroplasty (5) - Outlier of cost (2) - Multiple Linear Regressions Run Using Stata 14.1 Methods

Variables of Interest - Continuous variables (n = 3785) Variable Mean Min Max Cost 14772.37 2170.85 84952.97 Albumin (g/dl) 4.201215 2 5.5 BMI 33.05733 15 71 Age 62.40713 17 93 Hemoglobin (g/dl) 13.1525 5.7 19.6

Variables of Interest - Categorical variables (n = 3785) Readmission Status Joint Procedure Readmitted Not Readmitted Hip Knee Primary Revision

Distribution of Procedures Procedure Type 453 1091 2241 152 Hip Primary Hip Revision Knee Primary Knee Revision

25000 Results: Cost vs Joint/Procedure Cost vs Joint and Procedure Type 20000 Cost ($) 15000 10000 Procedure Type Primary Revision 5000 0 Knee Arthroplasty Hip Arthroplasty

Cost ($) Results: Cost vs Albumin Cost vs Albumin for Patients at UPHS 90000 80000 70000 60000 50000 40000 30000 20000 10000 0 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 Albumin (g/dl)

Results: Readmissions vs Albumin Variable Odds Ratio P value Albumin 0.4916561 0.001* BMI 1.021248 0.046 Age 1.021386 0.009* Hb 0.9603124 0.481 GFR 0.6193554 0.072 Cost 1.000016 0.158 Joint Type 0.9370874 0.713 Revision Type 1.322878 0.247

Conclusions - Joint type (knee/hip) and procedure type (primary/revision) are the main drivers of cost - Albumin significantly predicts cost - Lower albumin levels are associated with higher cost - Albumin is a significant driver of readmissions

What s Next? $ - Implications - Pre-screening patients for albumin Physiologic - Future prospective trial looking at the relationship between albumin levels Factors and cost/readmissions - Implications for bundled payment Albumin - Limitations - Albumin is likely correlated with other drivers of cost - Limited physiologic data from patients???

Outline - The Role of Albumin as a Risk Factor for Patient Outcomes in Orthopedic Surgery - Background - Aims and Significance - Methods - Results - Conclusions - Optimizing Fast-Track Pathways: Identifying Key Patient-Level and Surgery- Level Predictors - Background - Aims and Significance - Methods

Background - Early discharge protocols reduce readmission and mortality rates while resulting in significant economic savings - Fast-track pathways with a one-day length of stay (LOS) for total hip and knee arthroplasty (THA/TKA) may optimize patient outcomes through multimodal strategies (Sibia, 2017): - Early mobilization - Patient education - Non-opioid pain management - Aggressive postoperative fluid administration - Regional anesthesia

Background - Evidence that patients most likely to benefit tend to be younger, male, have lower BMI, shorter surgical times, and received spinal anesthesia - Evidence that older age and pre-existing comorbidities present considerable risks (Jorgensen, 2013) - Further identification of risk factors associated with positive and negative outcomes in fast-track THA/TKA is warranted

Aims and Significance - Determine patient-level and surgery-level factors most relevant to outcomes and cost in fast-track protocols for THA/TKA: Identify the patients best suited for fast-track - Hip and knee replacement (MS-DRG 469/470) represents Medicare s most frequently occurring and costly procedure - 446,148 discharges annually and a budget of $6.6 billion (CMS) - Increased implementation of fast-track protocols have significant implications in cost savings - Medicare s bundled payment programs - 2013: Bundled Payment for Care Improvement Initiative (BPCI) - 2016: Comprehensive Care for Joint Replacement (CRJ)

Methods - Data Source: University Health Consortium (Vizient), Hospital of the University of Pennsylvania - Key Variables - Admission Characteristics: Day, Source, Severity - Demographics/Patient Characteristics: Age, Sex, BMI, Race, Ethnicity, Insurance Status, Living Alone, Mobility Aids, Can Walk 2+ Blocks - Comorbidities: Diabetes, Hypertension, Coronary Artery Disease, COPD, Anemia, Renal Failure, Psychiatric Medications - Surgery Characteristics: Operative Time, Surgical Approach, Anesthesia Type, Estimated Blood Loss - Post-Surgery: Hours Until First PT, Distance Ambulated - Compare demographic and clinical characteristics for fast-track pathway versus standard pathway patients: Which patients are the best candidates for fast-track?

Andrew: Lessons Learned Balancing research and clinic Critically evaluating data Implementing research what is clinically relevant?

Robin: Lessons Learned Collaborative Nature of Research Unexpected Obstacles Translating Ideas into Practice

Dr. Atul Kamath Pio Finnah Paul Staehle Joanne Levy Safa Browne SUMR 2017 Cohort Acknowledgements

References: Albumin 1. Bohl DD, Shen MR, Kayupov E, Della Valle CJ. Hypoalbuminemia independently predicts surgical site infection, pneumonia, length of stay, and readmission after total joint arthroplasty. The Journal of Arthroplasty. 2016; 31(1): 15-21. 2. Courtney PM, Rozell, JC, Melnic CM, Sheth NP, Nelson CL. The effect of malnutrition and morbid obesity on complication rates following primary total joint arthroplasty. University of Pennsylvania Orthopaedic Journal. 2015; 25: 83-86. 3. Ellsworth B, Kamath AF. Malnutrition and Total Joint Arthroplasty. J Nat Sci. 2016; 3(3): e179. 4. Merkow RP, Ju MH, Chung JW, et al. Underlying reasons associated with hospital readmission following surgery in the united states. JAMA. 2015; 313(5): 483-495. 5. Walls JD, Abraham D, Nelson CL, Kamath AF, Elkassabany NM, Liu J. Hypoalbuminemia more than morbid obesity is an independent predictor of complications after total hip arthroplasty. The Journal of Arthroplasty. 2015; 30(12): 2290-2295.

References: Fast-Track 1. Do Shorter Lengths of Stay Increase Readmissions After Total Joint Replacements? Arthroplasty Today. (Sibia, 2017). 2. Role of Patient Characteristics for Fast-track Hip and Knee Arthroplasty. British Journal of Anesthesia. (Jorgensen, 2013). 3. Postoperative Morbidity and Discharge Destinations After Fast-Track Hip and Knee Arthroplasty in Patients Older Than 85 Years. Society for Ambulatory Anesthesiology. (Pitter, 2016). 4. Challenges in Post Discharge Function and Recovery: The Case of Fast-Track Hip and Knee Arthroplasty. British Journal of Anesthesia. (Aasvang, 2015). 5. Fall-related Admissions After Fast-Track Total Hip and Knee Arthroplasty- Cause of Concern or Consequence of Success? Clinical Interventions in Aging. (Jorgensen 2013). 6. New Medicare Data Available to Increase Transparency on Hospital Utilization. Centers for Medicare & Medicaid Services. https://www.cms.gov/newsroom/mediareleasedatabase/fact-sheets/2015-fact-sheets-items/2015-06-01.html (retrieved August 1, 2017).

Questions? Thank You!