The Relationship Between Surgical Volume and Patient Outcomes in Urologic Malignancies Geoffrey Gotto PGY-5 UBC Department of Urologic Sciences October 8 th, 2008 Objective To review the literature on the relationship between provider volume and outcomes in surgery for urologic malignancies 1
Rationale Growing interest in health-outcomes research (esp. in US) Medico-legal accountability Cost-containment A direct association exists between provider volume and improved outcomes in a number of surgical procedures CABG Pancreatic cancer Esophageal cancer etc. The magnitude of the association varies according to the procedure Major consequences in terms of health policy initiatives What is high volume? 2
Henry Ford (1863-1947) Born in Dearborn, Michigan Chief Engineer for the Edison Illuminating Co. Founder of the Ford Motor Co. Father of modern assembly lines Fordism Mass production of numbers of automobiles using the assembly line, coupled with high wages for workers 3
Does quantity equal quality? 4
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Learning (Experience) Curves Definition Efficiencies that arise from the learning and experience gained from repeated activities 1 st described by Herman Ebbinghaus in 1885 Mathematical model described by Theodore Paul Wright in 1936 6
Chuck Learning (Experience) Curves Explanations Labour efficiency Standardization, specialization, and methods improvements Technology-Driven Learning Automated production Information technology Better use of equipment Product redesign Value chain effects (suppliers + distributors) Network-building and use-cost reductions Shared experience effects 7
Economies of Scale Definition Efficiencies that arise from an increased scale of production Coalition of 150 US health care purchasers insuring over 34 million people Encourages high-volume providers for complex surgery 4 Leaps 1. Computer Physician Order Entry (CPOE) 2. Evidence-Based Hospital Referral 3. ICU Physician Staffing 4. Leapfrog Safe Practices Score 8
If the 1 st 3 leaps were implemented... 65,000 lives saved (Birkmeyer 2004) 907,000 medication errors avoided (Birkmeyer 2004) $41.5 billion saved (Conrad 2005) Implementing practices to inform patients regarding Hospital Volume Outcomes Surgeon Volume Outcomes http://www.cms.hhs.gov/quality/hospital 9
CABG RAMR > Average for 47% of high-volume hospitals (>500/yr) 33% of high-volume surgeons (>150/yr) 10
Lessons From Other Specialties 12 surgical procedures @ 1498 hospitals Case mix adjustment Mortality 25-41% with 200 cases / hospital / yr OHS CABG Vascular surgery THR TURP No change in mortality for Cholecystectomy 11
Design Systematic Medline review (1980-2000) MeSH search algorithm terms Outcome, Outcome assessment, Process assessment, Volume, Utilization, Frequency, Statistics, Regionalization, Names of clinical conditions and procedures 135 studies 27 different conditions and procedures Hospital (or physician) volume as independent variable Health outcomes as dependent variable Ref: Ann of Int Med 136(2) 2002 Conclusions Variability in methodology + definitions 88% of studies performed risk adjustment 70% found a significant relationship between volume and better outcome Relationship varied by condition and procedure Most notable in pancreatic and esophageal cancer surgery, pediatric cardiac surgery, ruptured AAA, AIDS Surgeon volume more important than hospital volume in CABG, carotid endarterectomy, AAA, and colorectal surgery Volume NOT predictive of outcome for individual hospitals or physicians Ref: Ann of Int Med 136(2) 2002 12
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Design 1994-1995 Sources Medicare National Inpatient Sample 6 cardiovascular procedures and 8 cancer surgeries (2.5 million cases) Statistical regression to describe relationship between hospital volume and in-hospital or 30-day mortality Risk-adjustment Ref: NEJM 346(15) 2002 14
Conclusions Patients undergoing many types of procedures can substantially improve their odds of survival by selecting a high-volume hospital Ref: NEJM 346(15) 2002 Design Medicare (1998-1999) 4 cardiovascular procedures and 8 cancer surgeries (474,108 cases) Statistical regression to describe relationship between surgeon volume and in-hospital or 30-day mortality Risk-adjustment Ref: NEJM 349(22) 2003 15
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Conclusions Associations between hospital volume and operative mortality largely mediated by surgeon volume Ref: NEJM 349(22) 2003 17
Design National Cancer Database (1994-2005) 243,103 patients Surgery for M0 colon, esophageal, liver, lung, gastric, pancreatic, or rectal cancer (1994-1999) Impact of hospital volume on: 60-day mortality 5-year conditional survival 18
Urologic Malignancies Survival Complications Cancer control QOL Costs Outcomes 19
Design Systematic review (MEDLINE, EMBASE, HMIC, Cochrane) 11 North American studies Prostate Bladder Kidney Primary outcome was mortality in 9/11 studies Case mix adjustment RRP outcomes (4 studies) mortality with hospital volume (2/3 studies) mortality with surgeon volume (1 study) Radical cystectomy outcomes (4 studies) mortality with hospital volume (1/3 studies) LOS with hospital volume (1 study) mortality with surgeon volume (1 study) Radical nephrectomy outcomes (4 studies) mortality with hospital volume (1 study) No change (1 study) mortality with hospital volume (1 study) 20
Design MEDLINE systematic review (1966-2004) Prostate Bladder Kidney Testis 21
Prostate Bladder 22
Kidney Testis 23
Prostate Design 11,522 consecutive RRPs from SEER-Medicare database (1992-1996) Ref: NEJM 346(15) 2002 24
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Design 1983-2002 44 surgeons at 2 large urban centers (MSKCC and Baylor) 4,629 patients with ct1-t3nxmo CaP 1 outcome = surgical margin status 26
Findings 26 surgeons > 10 RRPs during the study period Positive margins 10-48% Predictors based on multivariate analysis PSA ECE level Pathologic Gleason score Surgery date Surgical volume Surgeon 27
Design 5,238 consecutive RRP from SEER-Medicare database (1992-1996) 159 high-volume surgeons ( 20 RRP / 5 yr) 16% performed 48.7% of RRPs Adjustment for hospital volume, surgeon volume, and case mix Findings 30-day mortality = 0.5% Major post-op complication rate = 28.6% Late urinary complication rate = 25.2% Long-term incontinence = 6.7% Variation in rate of complications greater than expected by chance even after adjusting for covariates (p = 0.001) 28
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Design Systematic review (1980-2007) Meta-analysis of Observational Studies in Epidemiology Inclusion criteria Controlled studies English language Patient outcomes related to hospital/surgeon RRP volume 17 studies Ref: JU 180 Sept 2008 Findings Hospital volume > mean (43 RRP / yr) Mortality RR 0.62 (0.47 to 0.81) Morbidity 9.7% (-15.8 to -3.6%) Teaching hospitals Surgical complications 18% (-26 to -9%) Surgeon volume Not associated with mortality or margin status Incontinence 1.2% (-2.5 to -0.1) for each additional 10 RRP / yr LOS Ref: JU 180 Sept 2008 31
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Design 1 st 100 consecutive patients undergoing dvp (Feb 2003 Aug 2005) Single center with same surgical team 33
Conclusions Experience with dvp leads to a decrease in positive surgical margins especially at the apex and bladder neck Learning curves with new techniques may affect and predict oncologic outcomes Approximately 30 cases are needed to gain proficiency 34
Design 2,702 RRP from 5% national Medicare sample (2003-2005) Ref: Oncology 72 2008 35
CUOG P95A Multicenter Canadian study n = 549 CaP patients Randomized NHT 3 vs. 8 mo prior to RRP 1 Outcome = PSA recurrence Subset analysis Hospital volume 36
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Bladder 38
Design Nationwide Inpatient Sample (NIS) with ICD-9 codes 1,847 patients who underwent radical cystectomy for bladder cancer in 2003 Multivariate analysis of measures of hospital structure in HV vs. LV Capacity Staffing Health services Models used to determine impact of these variables on the volumeoutcome relationship Ref: JU 177 June 2007 Findings Substantial differences in hospital structure and resources Post-op mortality 3.2X at LV centers Ref: JU 177 June 2007 39
Improved access to diagnostic services Oncology Radiology 40
Improved access to interventional services ICU Interventional Radiology Hemodialysis Chemo Palliative care Pain management at HV centers Design Healthcare Utilization Project Nationwide Inpatient Sample (1988-1999) All inpatient discharges for radical cystectomy 41
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Design Nationwide Inpatient Sample 22,088 radical cystectomies for CaB (1988-2000) Findings >90% of surgeries performed in urban centers >45% of surgeries performed in teaching centers 43
Plausibility Consistent relationship seen over time and across studies Relationship is clinically plausible Likely that surgeons specialized in specific procedures will have better outcomes Consistent postoperative care at HV centers More access to diagnostic + interventional resources Radiology ICU CCU etc. Criticisms Observational studies Medicare data Readily available + inexpensive Population 65 May not give accurate representation of hospital/surgeon volume Differences in data quality across hospitals Problems with establishing timing of events Risk stratification to account for differences in patient populations Volume is an imperfect proxy for quality 44
Solutions 1. Regionalization ( Centers of Excellence ) Potentially jeopardizes medical services provided in affected regions Financial + logistic difficulties for patients + families Loss of continuity of care Difficulty recruiting + retaining surgeons in low-volume centers 2. Quality improvement initiatives based on an analysis of what is done differently at those centers with better outcomes Conclusions Growing interest in health-outcomes research and accountability A direct association exists between provider volume and improved outcomes The magnitude of the association varies according to the procedure The quality of the surgeon cannot be judged solely by volume Solutions include regionalization or quality improvement initiatives Further research is needed 45
Thank You 46