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Karl F Welke

Publications and source records attributed to Karl F Welke.

17 recordsLinked to original sources
PubMed2006

Contemporary impact of state certificate-of-need regulations for cardiac surgery: an analysis using the Society of Thoracic Surgeons' National Cardiac Surgery Database.

BACKGROUND: Prior research using administrative data associated certificate-of-need (CON) regulation for open heart surgery with higher hospital coronary artery bypass grafting (CABG) volume and lower CABG operative mortality rates in elderly patients. It is unclear whether these findings apply in a general population and after controlling for detailed clinical characteristics and region. METHODS AND RESULTS: Using the Society of Thoracic Surgeons' (STS) National Cardiac Surgery Database, we examined isolated CABG surgery volume, operative mortality, and the composite end point of operative mortality or major morbidity for the years 2000 to 2003. The presence of CON regulations for open heart surgery was ascertained from the National Directory of the American Health Policy Association and by contacting CON administrators. Results were analyzed nationally, by state, and by region (West, Northeast, Midwest, South) and were adjusted for clinical factors and both population density and region with mixed-effects hierarchical logistic regression models. During 2000 to 2003, there were 314,710 isolated CABG surgeries performed at 294 STS hospitals in CON states (n=27, including Washington, DC) and 280 512 procedures at 343 STS hospitals in non-CON states (n=24). Patient clinical characteristics were similar among CON and non-CON hospitals. States with CON regulations tended to have higher population densities and had significantly higher median hospital annual CABG volumes in each of the years 2000 to 2003 (P<0.005). This difference remained significant after adjustment for region and population density. Operative mortality was 2.52% for CON versus 2.62% for non-CON states (P=0.32). There was a significant association between CON law and operative mortality in the South. After adjustment for patient risk factors and region, there was a marginally significant reduction of mortality risk in states with CON regulation (adjusted OR 0.92, 95% CI 0.86 to 1.00). However, this difference was not statistically significant when a revised model accounted for random state effects. Similar volume and outcomes results were seen when the analysis was repeated with data from the national Medicare database. CONCLUSIONS: CON states have significantly higher hospital CABG surgery volumes but similar mortality compared with non-CON states. CON regulation alone is not a sufficient mechanism to ensure quality of care for CABG surgery.

Certificate of Need↗
PubMed2006

Invited commentary.

Explore the source record for details and available documents.

Coronary Artery Bypass, Off-Pump↗
PubMed2006

Current assessment of mortality rates in congenital cardiac surgery.

BACKGROUND: The purpose of this study is to evaluate whether published and widely quoted mortality rates for pediatric cardiac surgery accurately reflect current expectations. Our hypotheses are that (1) mortality rates at high-quality pediatric cardiac programs are lower than published national results despite (2) a change in case mix with a shift away from low complexity operations. METHODS: We requested data for all pediatric cardiac surgical procedures performed between 2001 and 2004 at 29 Congenital Heart Surgeon's Society (CHSS) member institutions (using CHSS as a surrogate for recognized high quality). Procedures were categorized by Risk Adjustment for Congenital Heart Surgery, version 1 (RACHS-1) category. In-hospital mortality rates for each category were calculated and compared with those in the 2002 manuscript of Jenkins and colleagues. RESULTS: We received data for 16,805 procedures from 11 institutions. In all, 12,672 operations (76%) could be placed into RACHS-1 categories. Overall in-hospital mortality for categorized operations was 2.9% and was most related to case mix. There was a significant decrease in the percentage of category 1 operations, and there were significant increases in category 2, 4, and 6 operations. There were significant decreases in category 2, 3, 4, and 6 mortality rates (Jenkins 2002 [CHSS]): (1) 0.4% [0.7%], (2) 3.8% [0.9%], (3) 8.5% [2.7%], (4) 19.4% [7.7%], (5) not applicable, and (6) 47.7% [17.2%]. There was no significant association between hospital surgical volume and mortality. CONCLUSIONS: This outcomes "footprint" suggests that we could hold ourselves accountable to higher benchmarks than those reflected by some published standards. Mortality rates declined, despite an increase in case mix complexity. The lack of association between hospital surgical volume and mortality suggests that other factors determine outcomes at high-quality institutions. In addition to continually validating our expectations for treatment, future research needs to identify these factors by understanding the system of care and identifying process measures that influence outcomes.

Cardiac Surgical Procedures↗
PubMed2005

Treatment variation in older black and white patients undergoing aortic valve replacement.

BACKGROUND: Most prior studies of racial differences in the delivery of cardiac care have focused on potential differences in treatment by individual physicians and hospitals. However, differential use of hospitals with variable practice patterns might also contribute to variations in care. METHODS AND RESULTS: We compared the use of bioprosthetic valves (BPVs) in 78,154 black and white Medicare beneficiaries > or =65 years of age undergoing aortic valve replacement in 904 US hospitals during 1999 through 2001. Generalized linear mixed models were used to account first for differences in patient characteristics and then for differences in hospitals used by black and white patients. BPV use was lower in black patients relative to white patients after adjustment for patient characteristics (relative risk, 0.93; 95% CI, 0.91 to 0.95; P<0.001). However, black patients were more likely to undergo surgery in hospitals in the lowest quintile of BPV use overall (29% versus 20% of white patients; P<0.001). After hospital-level variability in BPV use was accounted for, the use of BPVs was actually somewhat higher in black patients (relative risk, 1.06; 95% CI, 1.04 to 1.09; P<0.001). Model discrimination as measured by the c statistic was markedly higher after the addition of hospital effects (0.80 versus 0.59 for patient characteristics alone; P<0.001). CONCLUSIONS: Accounting for differences in hospitals preferentially used by black and white patients had a major impact on estimating racial differences in the use of BPVs in patients undergoing aortic valve replacement. Hospital-level effects explained a larger proportion of the variation in BPV use than race and other patient characteristics alone.

Adult↗
PubMed2005

Hospital volume and selection of valve type in older patients undergoing aortic valve replacement surgery in the United States.

BACKGROUND: Hospital volume has been linked to quality of care. The relation between hospital volume and recommended use of bioprosthetic valves in older patients undergoing aortic valve replacement (AVR) is unknown. METHODS AND RESULTS: We identified 80,470 patients aged > or =65 years undergoing isolated AVR (with or without bypass surgery) in 1045 US hospitals during 1999-2001 from Medicare Part A files. International Classification of Diseases, Ninth Revision, Clinical Modification codes were used to identify patients undergoing bioprosthetic valve (35.21) or mechanical valve (35.22) AVR. The sample was categorized into deciles on the basis of the valve surgery volume of the hospital. Generalized estimating equations determined the relative risk of receiving a bioprosthetic valve in different volume deciles, with adjustment for age, gender, race, comorbidity, and other factors. Bioprosthetic valve use increased (P<0.001) from 44% in 1999 to 52% in 2001 and with age (from 36% in patients aged 65 to 69 years to 60% in patients aged > or =90 years). Rates were directly related (P<0.001) to volume, rising from 28% in the 1st decile to 68% in the 10th decile. With the use of generalized estimating equations, the relative risk of bioprosthetic valve use, relative to the 1st decile, progressively increased from 1.2 (95% CI, 1.1 to 1.4) in the 2nd decile to 2.3 (95% CI, 1.9 to 2.7) in the 10th decile. CONCLUSIONS: Hospital volume was a strong predictor of bioprosthetic valve use in older patients undergoing AVR. The lower use of bioprosthetic valves in low-volume hospitals is at odds with recent guidelines recommending bioprosthetic valves in patients aged > or =65 years. These findings further support the use of volume as a marker of hospital quality.

Age Factors↗
PubMed2005

Limitations of hospital volume as a measure of quality of care for coronary artery bypass graft surgery.

BACKGROUND: While prior research has found an inverse relationship between hospital volume and mortality after coronary artery bypass graft surgery (CABG), the use of volume as a proxy for quality and a means for selecting hospitals is controversial. The objective of this study is to quantify the relationship between hospital volume alone and CABG mortality. METHODS: A retrospective cohort of 948,093 Medicare patients undergoing CABG in 870 US hospitals from 1996 to 2001 was categorized into quintiles, based on hospital CABG volume. Hospitals were also classified by volume criterion proposed by the Leapfrog Group. Logistic regression was used to adjust hospital mortality rates (in-hospital or within 30 days after CABG) for patient characteristics; discrimination of the volume categories was assessed by the c statistic. RESULTS: The range in risk-adjusted mortality for hospitals within the quintiles was substantial: 1% to 17% at very low, 2% to 12% at low, 2% to 10% at medium, 2% to 9% at high, and 3% to 11% at very high volume hospitals. Moreover, volume alone was a poor discriminator of mortality (c statistic = 0.52). Similar variation in adjusted mortality was seen within the Leapfrog low-volume (1% to 17%) and high-volume groups (2% to 11%), and the Leapfrog criterion was a poor discriminator of mortality (c statistic = 0.51). Of the 660 low-volume Leapfrog hospitals, 253 (38%) had risk-adjusted mortality rates that were similar to or lower than the overall risk-adjusted mortality of high-volume hospitals (5.2%). CONCLUSIONS: Volume alone, as a discriminator of mortality, is only slightly better than a coin flip (c statistic of 0.50).

Aged↗
PubMed2005

Evaluation of quality of care for congenital heart disease.

There is widespread recognition that surgical outcomes differ by surgeon and institution; however, the definition and measurement of quality in pediatric cardiac surgery is in its infancy. This article discusses the definition of quality, what has been done to define and measure quality of pediatric cardiac surgery, and how to proceed. Descriptions of assessment of quality by evaluating structure, process, and outcome measures; efforts to establish a global congenital heart surgery database; and a comparison of risk-adjusted mortality rates using the Risk Adjustment for Congenital Heart Surgery method are included.

Child↗
PubMed2005

Advances in congenital heart surgery.

PURPOSE OF REVIEW: We provide an overview of the past year's literature on congenital heart surgery. RECENT FINDINGS: This review focuses on selected disease entities, operative techniques, perioperative management strategies, and quality of care. SUMMARY: Congenital heart surgery is an evolving field.

Cardiac Catheterization↗
PubMed2004

Physician process and patient outcome measures for diabetes care: relationships to organizational characteristics.

BACKGROUND: Optimal diabetes management relies on providers adhering to evidence-based practice guidelines in the processes of care delivery and patients adhering to self-management recommendations to maximize patient outcomes. PURPOSE: To explore: (1) the degree to which providers adhere to the guidelines; (2) the extent of glycemic, lipid, and blood pressure control in patients with diabetes; and (3) the roles of organizational and patient population characteristics in affecting both provider adherence and patient outcome measures for diabetes. DESIGN: Secondary data analysis of provider adherence and patient outcome measures from chart reviews, along with surveys of facility quality managers. SAMPLE: We sampled 109 Veterans Affairs medical centers (VAMCs). RESULTS: Analyses indicated that provider adherence to diabetes guidelines (ie, hemoglobin A1c, foot, eye, renal, and lipid screens) and patient outcome measures (ie, glycemic, lipid, and hypertension control plus nonsmoking status) are comparable or better in VAMCs than reported elsewhere. VAMCs with higher levels of provider adherence to diabetes guidelines had distinguishing organizational characteristics, including more frequent feedback on diabetes quality of care, designation of a guideline champion, timely implementation of quality-of-care changes, and greater acceptance of guideline applicability. VAMCs with better patient outcome measures for diabetes had more effective communication between physicians and nurses, used educational programs and Grand Rounds presentations to implement the diabetes guidelines, and had an overall patient population that was older and with a smaller percentage of black patients. CONCLUSIONS: Healthcare organizations can adopt many of the identified organizational characteristics to enhance the delivery of care in their settings.

Aged↗
PubMed2003

Patient characteristics can predict improvement in functional health after elective coronary artery bypass grafting.

BACKGROUND: Despite many patients undergoing coronary artery bypass grafting (CABG) to improve their functional status, literature in this area is limited. The purpose of this study is to determine the effect of CABG on the functional health of an elective population and to identify preoperative patient characteristics associated with improved functional health after surgery. METHODS: Physical and mental functional health was assessed before and 6 months after surgery with the Short-Form Health Survey (SF-36) in 1,061 consecutive patients undergoing elective, isolated CABG. Survey data were complete in 529 patients (49.9%). Preoperative information on patient demographics, severity of cardiovascular illness, and disease comorbidities was also prospectively collected. RESULTS: Six months post-CABG the mean summary score for physical function improved by 31.9% over baseline (45.1 versus 34.2, p < 0.0001). The mean summary score for mental function improved by 7.3% over baseline (51.3 versus 47.8, p < 0.0001). Overall 73.2% of patients showed improvement in physical function and 41.6% showed improvement in mental function. Multivariate logistic regression identified certain preoperative characteristics as negative correlates of a significant improvement in physical functioning: body mass index 35 kg/m2 or greater, diabetes with sequelae, chronic obstructive pulmonary disease, peripheral vascular disease, and baseline physical function. Baseline mental function and chronic obstructive pulmonary disease were identified as negative correlates and older age as a positive correlate of significant improvement in mental functioning. CONCLUSIONS: Patient characteristics exist that impact functional health after elective CABG. Knowledge of these characteristics may be helpful when counseling patients about expected improvement in functional health with CABG.

Activities of Daily Living↗
PubMed2003

Myocardial apoptosis after cardioplegic arrest in the neonatal lamb.

OBJECTIVE: Myocardial apoptosis is observed after various cardiac injuries and is also a normal part of fetal cardiac development and early postnatal maturation. Cardioplegic arrest and reperfusion result in ischemic injury and oxidative stress, known triggers of apoptosis. Because the neonatal heart is in a proapoptotic state, we hypothesize that apoptosis is triggered after cardioplegic arrest in neonatal myocardium. METHODS: We started neonatal lambs (6-8 days old, n = 5) on cardiopulmonary bypass and administered cold crystalloid cardioplegia at 20-minute intervals. Total crossclamp time was 70 minutes, and bypass time was 90 minutes. After a six-hour recovery period, the hearts were excised and examined by using TdT-mediated dUTP nick-end labeling; radiolabeled DNA electrophoresis; fluorimetric caspase 3, 8, and 9 activity assay; mRNA microarray; and Western immunoblotting. Control lambs were anesthetized but did not undergo operation (n = 5) or were started on cardiopulmonary bypass for 90 minutes but not arrested (n = 5). RESULTS: Lambs subjected to cardioplegia had 5-fold more TdT-mediated dUTP nick-end labeling-positive nuclei compared with that seen in unoperated control animals (P =.007) and bypass-only control animals (P =.008). DNA laddering was present in all postcardioplegia hearts but absent among control hearts. Bad and Bcl-X mRNA transcription increased significantly. Caspase 3, 8, and 9 activities were slightly greater than those seen in control animals, but the differences were not significant. No change was detected in Bcl-2, Bax, or Bcl-xL proteins. CONCLUSIONS: In a clinically relevant model of neonatal cardioplegic arrest, increased apoptotic cell death is present 6 hours after reperfusion, and both proapoptotic and antiapoptotic responses are triggered. The clinical implications of apoptosis after cardioplegic arrest remain undetermined.

Animals↗
PubMedDate not supplied

Mortality as an outcome parameter for pediatric heart surgery.

Public interest in the performance of pediatric cardiac surgery programs is increasing. Mortality is the focus of outcomes reporting in pediatric cardiac surgery due both to its importance as an outcome and its accessibility in clinical and administrative data. However, assessment of mortality rates in congenital cardiac surgery is more complex than in adult cardiac surgery due to the wider range of procedures performed and the low frequency at which each individual procedure is performed. In order to accurately describe mortality, one must understand types of databases, data definitions, and risk adjustment methods. We review the risk adjustment methodologies and data sources used to produce mortality statistics. In addition, the issues of data quality and defining mortality are discussed.

Cardiac Surgical Procedures↗
PubMedDate not supplied

What factors influence provider knowledge of a congestive heart failure guideline in a national health care system?

Provider knowledge is a potential barrier to adherence to clinical guidelines. The purpose of this study is to assess the impact of organizational, provider, and guideline factors on provider knowledge of a congestive heart failure (CHF) clinical practice guideline (CPG) in the Veterans Health Administration (VHA) health care system. We developed a survey to investigate institution-level factors influencing the effectiveness of guideline implementation, including characteristics of the guideline, providers, hospital culture and structure, and regional network. Survey participants were quality managers, primary care administrators, and other individuals involved in primary care CPG implementation at 143 VHA hospitals with ambulatory care clinics. Potential explanatory variables were grouped into 11 factors. Multivariate regression models assessed the association between these factors and reported levels of provider knowledge regarding the CHF guideline at the hospital level. Two hundred forty surveys from 126 of 143 (88%) VHA hospitals were returned. Provider knowledge of the CHF guideline was estimated as "great" or "very great" by 58% of respondents. Three predictor factors (dissemination approaches, use of technology in guideline implementation, and hospital culture) were independently associated (P < or = .05) with provider knowledge. Specific variables within these categories that were related to greater knowledge included physician belief that guidelines were applicable to their practice, distribution of guideline summaries, use of guideline storyboards in clinic areas, the use of technology (eg, electronic patient records) in CPG implementation, and establishment of implementation checkpoints and deadlines. Provider knowledge of guidelines is affected by factors at various organizational levels: dissemination approaches, use of technology, and hospital culture. Guideline implementation efforts that target multiple organizational levels may increase provider knowledge.

Ambulatory Care Facilities↗
PubMedDate not supplied

Classifying the effectiveness of Veterans Affairs guideline implementation approaches.

Hospitals use numerous guideline implementation approaches with varying success. Approaches have been classified as consistently, variably, or minimally effective, with multiple approaches being most effective. This project assesses the Department of Veterans Affairs (VA) use of effective guideline implementation approaches. A survey of 123 VA quality managers assessed the approaches used to implement the chronic obstructive pulmonary disease, diabetes mellitus, congestive heart failure, and major depressive disorder guidelines. Approaches were categorized based on their effectiveness, and the total number of approaches used was calculated. Commonly used approaches were clinical meetings, summaries, and revised forms. Consistently and minimally effective approaches were used most frequently. Most hospitals used 4-7 approaches. Odds ratios demonstrated that consistently effective approaches were paired with minimally and variably effective approaches. The frequent use of consistently effective approaches and multiple approaches benefits VA adherence. However, VA hospitals should consider selective combinations of approaches to ensure the use of the most effective implementation methods.

Aged↗