Evaluation of quality of care for congenital heart disease

Evaluation of Quality of Care for Congenital Heart Disease Karl F. Welke, Jeffrey P. Jacobs, and Kathy J. Jenkins 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. Semin Thorac Cardiovasc Surg Pediatr Card Surg Ann 8:157-167 © 2005 Elsevier Inc. All rights reserved. KEYWORDS: Congenital heart disease, quality of health care, risk adjustment

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here is widespread recognition that cardiothoracic surgery outcomes differ by surgeon and institution.1,2 Public and private payers are using this variation to direct patients to high-performing providers.3,4 Patients and their families are becoming informed decision-makers and are searching the Internet and media sources when choosing a health care provider. Despite this trend, there remains active debate as to how to define and measure surgical quality. Although adult cardiac surgery has been the focus of much of this discussion and research, resulting in the elucidation of a few measures that reflect quality of care, the definition and measurement of quality in pediatric cardiac surgery remain nebulous. Despite this ambiguity, we are being asked to judge the quality of pediatric cardiac surgery programs. This article discusses the definition of quality, what has been done to define and measure quality of pediatric cardiac surgery, and how to proceed.

Defining Quality Several definitions of quality care have been put forth. Donabedian5 defined high-quality care as “that kind of care which is expected to maximize an inclusive measure

Division of Cardiothoracic Surgery, Oregon Health and Science University, Portland, OR; the Congenital Heart Institute of Florida, University of South Florida, Saint Petersburg, FL; and the Department of Cardiology, Children’s Hospital, Harvard, Boston, MA. Address reprint requests to Karl F. Welke, MD, Division of Cardiothoracic Surgery L353, Oregon Health and Science University, 3181 S.W. Sam Jackson Park Road, Portland, OR 97239-3098.

1092-9126/05/$-see front matter © 2005 Elsevier Inc. All rights reserved. doi:10.1053/j.pcsu.2005.02.002

of patient welfare, after one has taken account of the balance of expected gains and losses that attend the process of care in all its parts.” The American Medical Association defined high-quality care as that “which consistently contributes to the improvement or maintenance of quality and/or duration of life.”6 The Institute of Medicine stated that quality is the “degree to which health services for individuals and populations increase the likelihood of desired health outcomes and are consistent with current professional knowledge.”7,8 In their 2001 report “Crossing the Quality Chasm,” the Institute stated that efforts to improve our health care system should focus on making health care safe, effective, patient centered, timely, effective, and equitable.9 These definitions provide general outlines to consider when assessing the quality of health care.

Structure, Process, and Outcome To define specific measures that assess quality of care, three groups of data should be examined: structure, process, and outcome.10 Structural variables relate to the environment in which care is delivered. Process measures describe the care delivered. Outcome measures describe the results of the care. If structure or process measures are to be used to define quality of care, variation in these elements must affect outcome measures. If outcome measures are to be used, it must be demonstrated that they can be altered by changes in structure or process. 157

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Structure Structural elements describe the physical structure of the hospital, the equipment available, expertise and experience of staff, numbers of staff, and record-keeping systems such as computer physician order entry. The structural element most often used as a proxy for quality is procedural volume. Physician and hospital surgical volumes are inversely related to operative mortality for numerous procedures, including pediatric heart surgery. 11-15 Payers (eg, the Leapfrog group, a coalition of health care purchasers representing 40 million patients) are encouraging patients to seek care at highervolume hospitals and in some cases providing incentives to do so.3,4 The Leapfrog group has set volume standards for a number of operations, including coronary artery bypass grafting (⬎450 cases/hospital/year), as minimum standards for hospitals where their beneficiaries receive care. Volume criteria have not been formalized for pediatric heart surgery. Subspecialty training is another structural element related to improved outcomes. Board-certified vascular surgeons are more likely to engage in the process measures that result in lower mortality for carotid endarterectomy, and patients undergoing surgery for rectal cancer by board-certified colorectal surgeons have lower recurrence rates.16,17 The lack of certification in pediatric cardiac surgery and the inconsistency of training in the subspecialty during thoracic surgery residency and nonaccredited pediatric cardiac surgery fellowships make this a difficult element to evaluate. Adult surgical patients who are cared for in “closed” intensive care units where they are managed primarily by dedicated, board-certified intensivists have lower mortality rates.18 There is evidence to suggest that the same may be true in pediatric units.19 The care of pediatric cardiac surgical patients by individuals specifically trained and systems specifically designed to care for this patient group, such as intensive care units staffed round the clock by board-certified pediatric intensivists, dedicated pediatric anesthesia teams, and dedicated pediatric perfusion teams, would likely improve quality of care and should be investigated. Multidisciplinary rounds in intensive care units may be beneficial. High nurse-to-bed ratios are associated with lower mortality, as are current equipment and technology in intensive care settings.20,21 The advantages of structural variables as surrogates for quality include ready availability and low cost. Only a few relationships between structural measures and outcomes have been examined (mainly volume-operative mortality), and the measures studied are imperfect surrogates for quality.22,23 Despite the inverse relationship between volume and mortality, many small-volume hospitals outperform high-volume hospitals. The relationship is more complex in pediatric cardiac surgery due to the broad variety of surgical procedures and the relatively low volume of each individual procedure. Mortality rates calculated for each individual procedure are unstable, and a hospital or surgeon that performs a large number of low-complexity cases does not necessarily have expertise in more complex cases. In addition, structural measures may not be actionable by practitioners without major programmatic changes, and some actions may be detri-

mental to overall quality. For example, in an attempt to meet theoretical volume thresholds, a hospital could increase its volume of cases by repairing defects with minimal physiologic consequences (eg, very small ventricular septal defects) or by closing defects with surgery that could be closed using transcatheter intervention. Increasing the amount of health care available to a population does not necessarily lead to better outcomes and may be disadvantageous.24

Process Process measures describe the care that patients receive. A regional effort to identify and increase the use of appropriate process measures in adult cardiac surgery has improved mortality.25 The use of internal mammary to left anterior descending conduits and preoperative administration of ␤-blockers in coronary artery bypass grafting are associated with lower mortality and are being used as measures of quality.26 Process measures that represent quality in pediatric heart surgery are less well defined. Most available high-level evidence describes the nontechnical aspects of surgical care, such as those endorsed by the National Quality Forum regarding central venous catheter management, intensive care, and surgical antibiotic prophylaxis.27 Although these measures are applicable to all surgical procedures, there is a paucity of high-level evidence to support measures unique to specific procedures. The advantages of process measures are that they are often supported by high-level evidence, can have a large impact on outcomes, and are actionable by providers. A disadvantage is that the measurement of process variables can be time consuming and difficult. When investigating variables related to specific procedures, the study population must be correctly identified. In pediatric cardiac surgery, this can be problematic due to the large variety of cases. Investigation into processes of care is the main area needing attention to improve the quality of pediatric cardiac surgical care.

Outcome Outcome measures include complications, mortality, functional status, length of stay, and reoperation rates. Codman28 first tracked clinical outcomes in the early 1900s. Cardiac surgery has been at the forefront of more recent cardiac surgery clinical outcomes registries, with regional efforts in northern New England and New York being successful in lowering mortality rates for adult cardiac surgery.25,29 Nationally, the Society of Thoracic Surgeons has implemented a similar data collection system that provides feedback to member surgeons and hospitals regarding risk-adjusted mortality and complication rates.30 Outcomes have the advantage of being “end results.” Providers are more likely to support quality improvement efforts that measure outcomes. The main disadvantage of using outcomes data to measure quality is chance findings of differences due to small numbers. Each pediatric cardiac surgical procedure is done in low volume at any one institution, and most carry a low risk of mortality. As a result, the confidence

Evaluation of quality of care for CHD intervals surrounding the data points are wide and overlapping. Efforts have been made to solve this problem by devising summary scores that allow the range of pediatric cardiac surgery procedures to be combined, resulting in an aggregate mortality (RACHS and Aristotle). These scores are beneficial for describing the overall results of an institution but cannot be used to measure the quality of individual operations. Other measures, such as health-related quality of life and neurologic condition, may be better measures of quality for pediatric cardiac surgery. Long-term follow-up studies are needed to establish the effects of treatment choices on physical, psychologic, and educational development. These measures reflect issues important to patients and families and are not affected by low incidence rates.

Efforts to Create a Global Outcomes Database for Therapy of Congenital Heart Disease The rationale for the creation of outcomes databases for the treatment of congenital heart disease (CHD) is multifactorial. These databases function as a tool to support a variety of purposes: (1) Patient care for the 0.5 million new patients born annually worldwide with congenital cardiac disease, (2) research, (3) teaching, (4) practice management, (5) physician-driven resource allocation, and (6) physician-driven outcomes analysis. Events occurring at Bristol, England31; Denver, Colorado32-38; and Winnipeg, Canada39 point to the importance of physician-driven outcomes analysis. During the early and mid 1990s, the Society of Thoracic Surgeons (STS) in the North America and the European Association for Cardio-Thoracic Surgery (EACTS) created congenital heart surgery outcomes databases.40-43 Multiple lessons were learned from these early attempts to create multiinstitutional registries.42-44 Four primary requirements exist to allow a multi-institutional registry type database to facilitate meaningful multi-institutional outcomes analysis of medical interventions: (1) A common language or nomenclature, (2) a uniform core data set, (3) a mechanism to evaluate the complexity of cases, and (4) a mechanism to verify the completeness and accuracy of the data collected.

Nomenclature In response to the weaknesses recognized in the databases established by the STS and the EACTS, these two organizations42,43 established the International Congenital Heart Surgery Nomenclature and Database Project. This project addressed the first two requirements in the list above. A common nomenclature and a common core minimal data set have been adopted by the STS and the EACTS. The specifications of these items were published the Annals of Thoracic Surgery as a supplement in April 2000.42 This system of nomenclature is available free of charge at www.IPCCC.NET.

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Database The EACTS Congenital Heart Surgery Database (www. eactscongenitaldb.org) and the STS Congenital Heart Surgery Database (www.sts.org) use the same international standardized international nomenclature and common core data set developed by the International Congenital Heart Surgery Nomenclature and Database Project.42 Since 2000, this nomenclature and database has been used by the EACTS and STS to analyze the outcomes in over 40,000 patients with surgically treated congenital cardiac disease.

Complexity In 1999, the Aristotle Project was conceived, with input from members of the EACTS, the STS, the European Congenital Heart Surgeons Association (formerly known as the European Congenital Heart Surgeons Foundation), and the Congenital Heart Surgeons’ Society. The international Aristotle Committee was created to address complexity.45-48 This Committee has used the opinions of a panel of experts, made up of 50 congenital heart surgeons in 23 countries representing multiple societies. The rationale of the Aristotle Committee is to overcome the fact that, in the field of pediatric cardiac surgery, it is inadequate to analyze outcomes using raw measures of mortality alone without making adjustments for the complexity of cases. Case mix can vary greatly between institutions. Without complexity adjustment, surgeons and institutions caring for a higher proportion of patients with complex cardiac disease may be reluctant to participate in multi-institutional outcomes registries. The goal of the Aristotle Committee is to develop a system that permits quantitation of complexity based on the fact that it is a constant feature for a particular operation in a particular patient at a particular point in time. The method of adjustment allocates a Basic Score to each operation ranging from 1.5 to 15 and a level from 1 to 4 based on the Primary Procedure. This Aristotle Basic Complexity Score was calculated using three factors: the potential for mortality, the potential for morbidity, and the technical difficulty of the operation (Table 1). The EACTS and the STS incorporate the Aristotle Basic Complexity Score into their CHD databases (Table 2).49

Data Verification Collaborative efforts involving the EACTS and the STS are underway to address the need to develop mechanisms to verify the completeness and accuracy of the data.50-52 The importance of the verification of the accuracy of the data is demonstrated by the UKCCAD.53 In 2004, the UKCCAD published an analysis of 3,666 surgical procedures and 1,828 therapeutic catheterizations undertaken from 2000 and 2001 in the 13 tertiary centers in the United Kingdom that perform cardiac surgery or therapeutic cardiac catheterization in children with congenital cardiac disease. The mortality within 30 days of a procedure was identified by information supplied from the hospital databases and by independently validated data from the Office for National Statistics, using the unique National Health Service number given to all subjects born in

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Table 1 The Aristotle Basic Complexity Score and Aristotle Basic Complexity Level as Used in the Databases of the European Association for Cardio-Thoracic Surgery and the Society of Thoracic Surgeons51-54 Score

Mortality

1 2 3 4 5

<1% 1% to 5% 5% to 10% 10% to 20% >20%

Morbidity

Difficulty

ICU ICU ICU ICU ICU

Elementary Simple Average Important Major

0-24H 1D-3D 4D–7D 1W-2W > 2W

Total Complexity (Basic Score) (Basic Level) 1.5 to 5.9 1 6.0 to 7.9 2 8.0 to 9.9 3 10.0 to 15.0 4 Procedures Pleural drainage procedure Bronchoscopy Delayed sternal closure Mediastinal exploration Stemotomy wound drainage Intra-aortic balloon pump (IABP) insertion PFO, primary closure ASD repair, primary closure ASD repair, patch ASD, partial closure Pericardial drainage procedure PDA closure, surgical Pacemaker implantation, Permanent Pacemaker procedure Shunt, ligation and takedown ASD, common atrium (single atrium), septation ASD creation/enlargement Coronary artery fistula ligation ICD (AICD) implantation ICD (AICD) (automatic implantable cardioverter defibrillator) procedure Ligation, thoracic duct Diaphragm plication Atrial septal fenestration PAPVC repair Lung biopsy Ligation, pulmonary artery Decortication Pectus repair Valvuloplasty, pulmonic VSD repair, primary closure VSD repair, patch AVC (AVSD) repair, partial (incomplete) (PAVSD) AP window repair Valve replacement, truncal valve PA, reconstruction (plasty), main (trunk) Pericardiectomy Coarctation repair, end to end Coarctation repair, subclavian flap Coarctation repair, patch aortoplasty Vascular ring repair PA banding (PAB) PA debanding ECMO procedure

Total Complexity (Basic Score) (Basic Level) 1.5 1 1.5 1 1.5 1 1.5 1 1.5 1 2.0 1 3.0 1 3.0 1 3.0 1 3.0 1 3.0 1 3.0 1 3.0 1 3.0 1 3.5 1 3.8 1 4.0 1 4.0 1 4.0 1 4.0 1 4.0 4.0 5.0 5.0 5.0 5.0 5.0 5.3 5.6 6.0 6.0 6.0 6.0 6.0 6.0 6.0 6.0 6.0 6.0 6.0 6.0 6.0 6.0

1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 2 2 2 2

Mortality

Morbidity

Difficulty

0.5 0.5 0.5 0.5 0.5 0.5 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.5 1.0 1.0 1.0 1.5 1.5

0.5 0.5 0.5 0.5 0.5 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2.0 2.0 1.0 1.0

0.5 0.5 0.5 0.5 0.5 0.5 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.8 1.0 1.0 1.5 1.5

1.0 1.0 2.0 2.0 1.5 1.5 1.0 2.0 1.8 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0

2.0 2.0 2.0 1.0 2.0 2.0 1.0 1.0 1.8 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 3.0

1.0 1.0 1.0 2.0 1.5 1.5 3.0 2.3 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0

Evaluation of quality of care for CHD

161

Table 1 Continued

Aortic stenosis, subvalvar, repair Shunt, systemic to pulmonary, modified BlalockTausaig shunt (MBTS) AVC (AVSD) repair, intermediate (transitional) RVOT procedure Valve replacement, pulmonic (PVR) Cor triatriatum repair Shunt, systemic to pulmonary, central (from aorta or to main pulmonary artery) Bidirectional cavopulmonary anastomosis (BDCPA) (bidirectional Glenn) Valvuloplasty, truncal valve Anomalous systemic venous connection repair Occlusion MAPCA(s) Valvuloplasty, tricuspid Valve excision, tricuspid (without replacement) DCRV repair Valve replacement, aortic (AVR), mechanical Valve replacement, aortic (AVR), bioprosthetic Aortic arch repair Glenn (unidirectional cavopulmonary anastomosis) (unidirectional Glenn) Right/left heart assist device procedure Ventricular septal fenestration TOF repair, ventriculotomy, nontransanular patch Valve replacement, tricuspid (TVR) Conduit placement, RV to PA Aortic stenosis, supravalvar, repair Sinus of Valsalva, aneurysm repair Valve replacement, mitral (MVR) Coronary artery bypass Bilateral bidirectional cavopulmonary anastomosis (BBDCPA) (bilateral bidirectional Glenn) Atrial baffle procedure (non-Mustard, nonSenning) PA, reconstruction (plasty), branch, central (within the hilar bifurcation) PA, reconstruction (plasty), branch, peripheral (at or beyond the hilar bifurcation) Coarctation repair, interposition graft PAPVC, scimitar, repair Systemic venous stenosis repair TOF repair, no ventriculotomy TOF repair, ventriculotomy, transanular patch TOF repair, RV-PA conduit Conduit reoperation Conduit placement, LV to PA Valvuloplasty, aortic Aortic root replacement Valvuloplasty, mitral Mitral stenosis, supravalvar mitral ring repair Coarctation repair, end to end, extended Arrhythmia surgery - atrial, surgical ablation Hemi-Fontan Aneurysm, ventricular, right, repair Aneurysm, pulmonary artery, repair Cardiac tumor resection Pulmonary embolectomy LV to aorta tunnel repair

Score

Mortality

6.3 6.3

2 2

2.0 2.0

6.5 6.5 6.5 6.8 6.8

2 2 2 2 2

6.8

Morbidity

Difficulty

1.8

2.5 2.0

2.3

2.0 2.0 2.0 2.0 2.0

2.0 2.0 2.0 2.0 2.0

2.5 2.5 2.5 2.8 2.8

2

2.3

2.0

2.5

7.0 7.0 7.0 7.0 7.0 7.0 7.0 7.0 7.0 7.0

2 2 2 2 2 2 2 2 2 2

2.0 2.0 2.0 2.0 3.0 2.0 2.0 2.0 2.0 2.5

2.0 2.0 2.0 2.0 3.0 2.0 2.0 2.0 2.0 2.0

3.0 3.0 3.0 3.0 1.0 3.0 3.0 3.0 3.0 2.5

7.0 7.5 7.5 7.5 7.5 7.5 7.5 7.5 7.5 7.5

2 2 2 2 2 2 2 2 2 2

2.0 3.0 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5

3.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0

2.0 2.5 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0

7.8

2

2.8

2.0

3.0

7.8

2

2.8

2.0

3.0

7.8

2

2.8

2.0

3.0

7.8 8.0 8.0 8.0 8.0 8.0 8.0 8.0 8.0 8.0 8.0 8.0 8.0 8.0 8.0 8.0 8.0 8.0 8.0 8.3

2 3 3 3 3 3 2 3 3 3 3 3 3 3 3 3 3 3 3 3

2.8 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 2.5 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0

2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 3.0 2.3

3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.5 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 2.0 3.0

K.F. Welke, J.P. Jacobs, and K.J. Jenkins

162 Table 1 Continued

Valve replacement, aortic (AVR), homograft Senning Aortic root replacement, mechanical Aortic aneurysm repair VSD, multiple, repair VSD creation/enlargement AVC (AVSD) repair, complete (CAVSD) Pulmonary artery origin from ascending aorta (hemitruncus) repair TAPVC repair Pulmonary atresia - VSD (including TOF, PA) repair Valve closure, tricuspid (exclusion, univentricular approach) 1 1/2 ventricular repair Fontan, atrio-pulmonary connection Fontan, atrio-ventricular connection Fontan, TCPC, lateral tunnel, fenestrated Fontan, TCPC, lateral tunnel, non-fenestrated Fontan, TCPC, external conduit, fenestrated Fontan, TCPC, external conduit, non-fenestrated Congenitally corrected TGA repair, VSD closure Mustard Pulmonary artery sling repair Aneurysm, ventricular, left, repair TOF - absent pulmonary valve repair Transplant, heart Aortic root replacement, homograft Damus-Kaye-Stansel procedure (DKS) (creation of AP anastomosis without arch reconstruction) Arterial switch operation (ASO) Rastelli Anomalous origin of coronary artery from pulmonary artery repair Ross procedure DORV, intraventricular tunnel repair Interrupted aortic arch repair Truncus arteriosus repair TOF - AVC (AVSD) repair Pulmonary atresia - VSD - MAPCA (pseudotruncus) repair Unifocalization MAPCA(s) Konno procedure Congenitally corrected TGA repair, atrial switch and Rastelli Congenitally corrected TGA repair, VSD closure and LV to PA conduit Arterial switch operation (ASO) and VSD repair REV DOLV repair Aortic dissection repair Pulmonary venous stenosis repair Partial left ventriculectomy (LV volume reduction surgery) (Batista) Transplant, lung(s) Ross-Konno procedure Transplant, heart and lung(s) Congenitally corrected TGA repair, Aatrial switch and ASO (double switch) Norwood procedure HLHS biventricular repair

Score

Mortality

8.5 8.5 8.8 8.8 9.0 9.0 9.0 9.0

3 3 3 3 3 3 3 3

3.0 3.0 3.3 3.0 3.0 3.0 3.0 3.0

9.0 9.0

3 3

9.0

Morbidity

Difficulty

2.0

3.5 2.5 2.0 2.8 2.5 3.0 3.0 3.0

3.0 3.5 3.0 3.5 3.0 3.0 3.0

3.0 3.0

3.0 3.0

3.0 3.0

3

4.0

3.0

2.0

9.0 9.0 9.0 9.0 9.0 9.0 9.0 9.0 9.0 9.0 9.0 9.3 9.3 9.5 9.5

3 3 3 3 3 3 3 3 3 3 3 3 3 3 3

3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.5 3.0

3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 2.5 3.0 3.3 2.0 3.0

3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.5 3.3 3.0 4.0 3.5

10.0 10.0 10.0

4 4 4

3.5 3.0 3.0

3.0 3.0 3.0

3.5 4.0 4.0

10.3 10.3 10.8 11.0 11.0 11.0

4 4 4 4 4 4

4.0 3.3 3.8 4.0 4.0 4.0

2.3 3.0 3.0 3.0 3.0 3.0

4.0 4.0 4.0 4.0 4.0 4.0

11.0 11.0 11.0

4 4 4

4.0 4.0 4.0

3.0 3.0 3.0

4.0 4.0 4.0

11.0

4

4.0

3.0

4.0

11.0 11.0 11.0 11.0 12.0 12.0

4 4 4 4 4 4

4.0 4.0 4.0 4.0 4.0 4.0

3.0 3.0 3.0 3.0 4.0 4.0

4.0 4.0 4.0 4.0 4.0 4.0

12.0 12.5 13.3 13.8

4 4 4 4

4.0 4.5 4.0 5.0

4.0 3.0 5.0 3.8

4.0 5.0 4.3 5.0

14.5 15.0

4 4

5.0 5.0

4.5 5.0

5.0 5.0

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Table 2 Data from the European Association for Cardio-Thoracic Surgery and the Society of Thoracic Surgeons Congenital Heart Surgery Databases between 1998 and 200455 All

0 to 28 d

29 d to 1 yr

Other

Society of Thoracic Surgeons Eligible patients Discharge mortality, n Discharge mortality, % Basic complexity score

18,928 825 4.4 7.1

3,988 487 12.2 8.6

6,152 202 3.3 7.0

8,788 136 1.5 6.5

European Association for Cardio-Thoracic Surgery Eligible patients Discharge mortality, n Discharge mortality, % Basic complexity score

21,916 1,097 5.4 6.5

4,273 514 13.3 7.6

7,316 377 5.56 6.6

10,327 206 2.1 5.9

the United Kingdom. Of 194 deaths recorded within 30 days by the Office for National Statistics, 42 (21.6%) were detected by central tracking but had not been volunteered by the tertiary centers themselves. In other words, the databases under-reported the deaths occurring within 30 days by slightly more than one fifth even though those working in the tertiary centers were aware that the data would be independently verified. Multiple potential solutions to develop mechanisms to assure and verify the completeness and accuracy of data are being explored through a collaborative project involving the EACTS and the STS.

The Future Participation in a properly structured multi-institutional outcomes database provides multiple advantages to all institutions seeking to treat congenital cardiac malformations. The users of these databases have different needs. A multi-institutional registry aims to collect “some of the data about all of the patients,” whereas an academic database aims to collect “all of the data about some of the patients.”44 A multi-institutional registry addresses the collection of a small number of items from a large number of institutions. A scientific database, created to compare methods or treatments, will need large and accurate sets of data from a few highly reliable institutions. A properly structured multi-institutional outcomes database can be used as a tool for quality improvement. The database can be used as a benchmark upon which to grade surgical and institutional performance and as a registry to identify more (or less) successful strategies of management. The database can be used to measure application of new treatment strategies. Thus, the database can be used as a tool for patient care, teaching, research, practice management, and quality improvement. Efforts are ongoing to involve those working in Africa, Asia, Australia, and South America. The overall goal of such a global database is to improve the outcomes of treatment of congenital cardiac malformations. The benefits of multi-institutional gathering and sharing of data are global, with the long-term goal of the continued improvement in the quality of therapeutic options worldwide.54

“Evaluation of quality of care is a duty of the modern medical practice. A reliable method of quality evaluation able to compare fairly institutions and inform a patient and his family of the potential risk of a procedure is clearly needed.”55 The efforts to create the multi-institutional outcomes database represent one important tool for quality improvement. Other tools include the development of coordinated regional efforts to care for patients with CHD56 and the improvement of programmatic infrastructure of the individual programs caring for patients with CHD.57 Part of being a professional is self-regulating one’s profession and taking measures to improve the state of the art in this profession. This process of professional self-regulation and self-improvement needs to be data driven.58,59

Risk Adjustment for Congenital Heart Surgery, Version 1 Given the marked improvements in survival after congenital heart surgery over the past two decades, program evaluation and comparison must move toward nonmortality outcomes, such as neurologic or functional status. Despite this, large differences in risk of death remain present for patients operated on at different institutions, and comparison of risk-adjusted mortality rates remains a critical component of program evaluation. Because of the wide diversity of procedures, each in small numbers, that are typical of any pediatric cardiac surgeon’s caseload, attempts to benchmark performance based on results for individual procedures are plagued by small sample sizes, wide confidence limits, and variation in performance for different procedures. To overcome these difficulties, risk-adjustment methods have been developed to allow comparisons across an entire case mix, resulting in a single “measure” of performance.

Development The first of these methods to be developed, and the only one that has been fully validated, is known as RACHS-1.60 RACHS-1 was created by an expert panel of pediatric cardiologists and pediatric cardiac surgeons and has been shown

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Table 3 Individual Procedures by Risk Category, Including European Paediatric Cardiac Codes Risk category 1 Atrial septal defect surgery (including atrial septal defect secundum, sinus venosus atrial septal defect, patent foramen ovale closure) 12.00.55; 12.01.01,02,03,08,10,53 Aortopexy Patent ductus arteriosus surgery at age >30 days 12.24.10,20 Coarctation repair at age >30 days 12.18.00,01,02,03,10 Partially anomalous pulmonary venous connection surgery 12.00.02,17 Risk category 2 Aortic valvotomy or valvuloplasty at age >30 days 12.16.02,04,11,80,85 Subaortic stenosis resection 12.07.01; 12.08.22 Pulmonary valvotomy or valvuloplasty 12.13.02 Pulmonary valve replacement 12.13.21,22 Right ventricular infundibulectomy 12.06.00,35,41; 12.08.21 Pulmonary outflow tract augmentation 12.06.38; 12.14.01 Repair of coronary artery fistula 12.23.07; 12.23.11 Atrial septal defect and ventricular septal repair 12.01.01,02,03,08,10,53 AND 12.08.01,02,03 Atrial septal defect primum repair 12.04.01 Ventricular septal defect repair 12.08.01,02,03 Ventricular septal defect closure and pulmonary valvotomy or infundibular resection 12.08.01,02,03 AND 12.06.01,35,41; 12.08.21 Ventricular septal defect closure and pulmonary artery band removal 12.08.01,02,03 AND 12.14.03 Repair of unspecified septal defect Total repair of tetralogy of Fallot 12.26.01,13,20 Repair of total anomalous pulmonary veins at age >30 days 12.00.00 Glenn shunt 12.31.11,15,44,45 Vascular ring surgery 12.17.11,32 Repair of aorto-pulmonary window 12.12.01 Coarctation repair at age <30 days 12.18.00,01,02,03,10 Repair of pulmonary artery stenosis 12.14.20,21,22 Transection of pulmonary artery Common atrium closure 12,01,22 Left ventricular to right atrial shunt repair Risk category 3 Aortic valve replacement 12.16.21,22,28,29 Ross procedure 12.16.30 Left ventricular outflow tract patch 12.07.13 Ventriculomyotomy 12.07.11 Aortoplasty 12.16.40,42,66,67 Mitral valvotomy or valvuloplasty 12.03.00,01,03,04; 12.48.02 Mitral valve replacement 12.03.11 Valvectomy of tricuspid valve 12.02.22 Tricuspid valvotomy or valvuloplasty 12.02.00,02,04 Tricuspid valve replacement 12.02.11 Tricuspid valve repositioning for Ebstein anomaly at age >30 days Dx 06.01.34 AND 12.02.00,02 Repair of anomalous coronary artery without intrapulmonary tunnel 12.23.00 Repair of anomalous coronary artery with intrapulmonary tunnel (Takeuchi) 12.23.00 Closure of semilunar valve, aortic or pulmonary 12.13.15,12.16.61 Right ventricular to pulmonary artery conduit 12.36.01,10 Left ventricular to pulmonary artery conduit 12.36.02,10 Repair of double outlet right ventricle with or without repair of right ventricular obstruction 12.27.01,02,20 Fontan procedure 12.30.01,13,28,32,50,51,54 Repair of transitional or complete atrioventricular canal with or without valve replacement 12.05.01,10,20,40,45 Pulmonary artery band 12.14.02 Repair of tetralogy of Fallot with pulmonary atresia 12.28.01,11 Repair of cor triatriatum 12.01.31 Systemic to pulmonary artery shunt 12.31.03,04,05,06,30,46 Atrial switch operation 12.29.01,02 Arterial switch operation 12.29.21 Reimplantation of anomalous pulmonary artery 12.14.30 Annuloplasty 12.16.04 Repair of coarctation and ventricular septal defect closure 12.08.01,02,03 AND 12.18.00,01,02,03,10

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Table 3 Continued Excision of intracardiac tumor 12.32.10 Risk category 4 Aortic valvotomy or valvuloplasty at age <30 days 12.16.02,04,11,80,85 Konno procedure 12.07.12 Repair of complex anomaly (single ventricle) by ventricular septal defect enlargement 12.08.06,35 Repair of total anomalous pulmonary veins at age <30 days 12.00.00 Atrial septectomy 12.01.42,43,90 Repair of transposition, ventricular septal defect, and subpulmonary stenosis (Rastelli) 12.29.11 Atrial switch operation with ventricular septal defect closure 12.29.01,02 AND 12.08.02,03 Atrial switch operation with repair of subpulmonary stenosis 12.29.01,02 AND 12.26.21,41 Arterial switch operation with pulmonary artery band removal 12.29.21 AND 12.14.03 Arterial switch operation with ventricular septal defect closure 12.29.21 AND 12.08.02,03 Arterial switch operation with repair of subpulmonary stenosis 12.29.21 AND 12.26.21,41 Repair of truncus arteriosus 12.11.00 Repair of hypoplastic or interrupted arch without ventricular septal defect closure 12.21.00 Repair of hypoplastic or interrupted aortic arch with ventricular septal defect closure 12.21.00 AND 12.08.01,02,03 Transverse arch graft 12.18.15 Unifocalization for tetralogy of Fallot and pulmonary atresia 12.25.00 Double switch 12.29.25 Risk category 5 Tricuspid valve repositioning for neonatal Ebstein anomaly at age <30 days Dx 06.01.34 AND 12.02.00,02 Repair of truncus arteriosus and interrupted arch 12.11.00 AND 12.21.00 Risk category 6 Stage 1 repair of hypoplastic left heart syndrome (Norwood operation) 12.10.00 Stage 1 repair of nonhypoplastic left heart syndrome conditions 12.10.00 Damus-Kaye-Stansel procedure 12.09.03

to have a high level of discrimination when applied to prospective and retrospective clinical data and administrative data.60,61 The wide range of procedural and anatomic diversity present within a cardiac surgery case mix is simplified by grouping procedures together into risk groups; risk group, age at procedure, prematurity, presence of a major noncardiac anomaly, and multiple surgical procedures performed simultaneously are included in the RACHS-1 method.

Application To apply RACHS-1 in its simplest form, an individual program needs to create a list of pediatric cardiac surgical cases and assign a RACHS-1 risk group to each procedure (Table 3). Any standardized nomenclature or coding system can be used for this purpose; for example, RACHS-1 categories for procedures included on the Short List developed by the Nomenclature Working Group of the Society for Thoracic Surgeons and European Association for Cardiothoracic Surgery, according to European Paediatric Cardiac Codes, are shown in Table 1.62 If multiple procedures are performed at the same operation, the case should be placed in the risk group of the highest procedure. Mortality rates can then be computed for each Risk Group and can be followed over time or compared with results from the literature or from other programs. Interesting trends can be observed by examining differences in institutional performance among different risk categories.63 Mortality rates for each of the RACHS-1 categories from the HealthCare Utilization Project Kids Inpatient Database (KID) for calendar year 2000 are shown in Fig 1.

To apply RACHS-1 in its more complex form, the other variables, including age (ⱕ30 days, 31 days to 1 year, ⬎1 year), prematurity ⬍37 weeks (Yes/No), presence of a major noncardiac anomaly (Yes/No), and whether more than one surgical procedure was performed simultaneously (Yes/No) must be collected. Model coefficients using logistic regression from the literature60 or from the comparison data set62 can then be used to create an expected mortality rate, based on the case mix performed, that would have been expected had the outcomes from the program been equivalent to the literature or comparison data set. The observed mortality rate is compared with the expected rate to determine how the institution performed relative to the literature or comparison.

Figure 1 Mortality rates and 95% confidence intervals for each of the six RACHS-1 risk categories using data from the Health Care Utilization Project KID 2000.

166 The ratio of the observed mortality rate and the expected mortality rate is known as a “standardized mortality ratio” (SMR); SMR ⬍1 means lower risk-adjusted mortality than the benchmark, identical to the benchmark, and ⬎1 higher than the benchmark. Because the SMR is on a log scale, a center with an SMR of 0.5 has a risk-adjusted mortality that is two times better than average, and a center with an SMR of 2.0 is two times worse than average. The SMR can be multiplied by the average mortality in the comparison data set to obtain a risk-adjusted mortality rate. The SMR values for the 10 largest centers in the KID2000 data set range from 0.00 to 1.55 (median 0.87). Given the logarithmic nature of the SMR, there is a nearly 10-fold difference in risk-adjusted mortality among these centers, emphasizing the continued value of mortality comparisons to evaluate quality for pediatric heart surgery.

Conclusion High-quality health care begins with selection of the most appropriate treatment for a patient followed by provision of that care in a superior fashion. Each provider must be conscious of the care they provide and the outcomes that result. One should approach each patient asking not only “How can I provide the best care in this case?” but also “How can I improve the care I provide?” By maintaining a database of cases, one can examine trends and track the results of interventions designed to improve care. The data must be accurate, complete, and germane to the question being investigated. Surgeons must look beyond their technical skills in the operating room and see themselves as part of a system of care. More investigations are needed into the processes of care and their relationships to outcomes. Although the overall quality of pediatric cardiac care can be improved somewhat by eliminating the poorest performing hospitals, far more patients will benefit from the majority of hospitals and providers implementing processes of care that improve results. Outcomes examined must not only include mortality and complications, but also more patient-focused measures, such as neurologic status and health-related quality of life. In striving to provide the highest quality of care, practitioners must remain conscious of the preferences and goals of the patients and their families because they must live with the results.

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