Optimizing PatientOutcomes Following Orthopedic Surgery: The Role of Albuminand the Case For Fast-TrackAndrew NgRobin WangMentor: 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
- Marker for malnourishment - Immunocompromised patients (Bohl et
al, 2016 & Courtney et al, 2015)
Blood vessel
Albumin
Lymph fluid
Hypoalbuminemia HyperalbuminemiaNormal Albumin
3.5 g/dL 5.0 g/dL
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
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
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
Methods- 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
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
Readmitted Not Readmitted
Joint
Hip Knee
Procedure
Primary Revision
Distribution of Procedures
1091
152
2241
453
Procedure Type
Hip Primary Hip Revision Knee Primary Knee Revision
Results: Cost vs Joint/Procedure
0
5000
10000
15000
20000
25000
Knee Arthroplasty Hip Arthroplasty
Cost
($) Procedure Type
Cost vs Joint and Procedure Type
Primary
Revision
Results: Cost vs Albumin
0100002000030000400005000060000700008000090000
1.5 2 2.5 3 3.5 4 4.5 5 5.5 6
Cost
($)
Albumin (g/dL)
Cost vs Albumin for Patients at UPHS
Results: Readmissions vs AlbuminVariable 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- Future prospective trial looking at the
relationship between albumin levels and cost/readmissions
- Implications for bundled payment - Limitations
- Albumin is likely correlated with other drivers of cost
- Limited physiologic data from patients
$
Albumin
Physiologic Factors
???
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- 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)
- 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
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
Acknowledgements• Dr. Atul Kamath• Pio Finnah• Paul Staehle• Joanne Levy• Safa Browne• SUMR 2017 Cohort
References: Albumin1. 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).
Thank You!
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