Gerald T. O'Connor

Multivariate prediction of in-hospital mortality associated with coronary artery bypass graft surgery. Northern New England Cardiovascular Disease Study Group.

BackgroundA prospective regional study was conducted to identify factors associated with in-hospital mortality among patients undergoing isolated coronary artery bypass graft surgery (CABG). A prediction rule was developed and validated based on the data collected. Methods and ResultsData from 3,055 patients were collected from five clinical centers between July 1, 1987, and April 15, 1989. Logistic regression analysis was used to predict the risk of in-hospital mortality. A prediction rule was developed on a training set of data and validated on an independent test set. The metric used to assess the performance of the prediction rule was the area under the relative operating characteristic (ROC) curve. Variables used to construct the regression model of in-hospital mortality included age, sex, body surface area, presence of comorbid disease, history of CABG, left ventricular end-diastolic pressure, ejection fraction score, and priority of surgery. The model significantly predicted the occurrence of in-hospital mortality. The area under the ROC curve obtained from the training set of data was 0.74 (perfect, 1.0). The prediction rule performed well when used on a test set of data (area, 0.76). The correlation between observed and expected numbers of deaths was 0.99. ConclusionsThe prediction rule described in this report was developed using regional data, uses only eight variables, has good performance characteristics, and is easily available to clinicians with access to a microcomputer or programmable calculator. This validated multivariate prediction rule would be useful both to calculate the risk of mortality for an individual patient and to contrast observed and expected mortality rates for an institution or a particular clinician.

A regional intervention to improve the hospital mortality associated with coronary artery bypass graft surgery. The Northern New England Cardiovascular Disease Study Group.

OBJECTIVE To determine whether an organized intervention including data feedback, training in continuous quality improvement techniques, and site visits to other medical centers could improve the hospital mortality rates associated with coronary artery bypass graft (CABG) surgery. DESIGN Regional intervention study. Patient demographic and historical data, body surface area, cardiac catheterization results, priority of surgery, comorbidity, and status at hospital discharge were collected on CABG patients in Northern New England between July 1, 1987, and July 31, 1993. SETTING This study included all 23 cardiothoracic surgeons practicing in Maine, New Hampshire, and Vermont during the study period. PATIENTS Data were collected on 15,095 consecutive patients undergoing isolated CABG procedures in Maine, New Hampshire and Vermont during the study period. INTERVENTIONS A three-component intervention aimed at reducing CABG mortality was fielded in 1990 and 1991. The interventions included feedback of outcome data, training in continuous quality improvement techniques, and site visits to other medical centers. MAIN OUTCOME MEASURE A comparison of the observed and expected hospital mortality rates during the postintervention period. RESULTS During the postintervention period, we observed the outcomes for 6488 consecutive cases of CABG surgery. There were 74 fewer deaths than would have been expected. This 24% reduction in the hospital mortality rate was statistically significant (P = .001). This reduction in mortality rate was relatively consistent across patient subgroups and was temporally associated with the interventions. CONCLUSION We conclude that a multi-institutional, regional model for the continuous improvement of surgical care is feasible and effective. This model may have applications in other settings.

Differences between men and women in hospital mortality associated with coronary artery bypass graft surgery. The Northern New England Cardiovascular Disease Study Group.

BACKGROUND A prospective study of patients undergoing coronary artery bypass graft surgery (CABG) was conducted to examine differences in hospital mortality by sex. Outcome data on 3055 CABG patients undergoing operation between 1987 and 1989 were examined for differences in patient, disease, and treatment factors. METHODS AND RESULTS Odds ratios (OR), risk differences, and 95% confidence intervals (CI95%) were calculated. Mortality rates for women (7.1%) and men (3.3%) differed, the OR (women versus men) being 2.23 (CI95%, 1.58 to 3.15). Women were older, more often diabetic, and had more urgent or emergent surgery; adjustment yielded an OR (women versus men) of 1.75 (CI95%, 1.17 to 2.63). Body surface area (BSA) was associated with risk of death in both sexes (P = .007) and positively associated with coronary artery luminal diameters. After adjustment for BSA, sex was no longer significantly associated with mortality (OR [women versus men] of 1.18; CI95%, 0.72 to 1.95). Internal mammary artery (IMA) grafting was performed less frequently among women than men (64.8% versus 78.4%, P < .001). Smaller BSA and absence of IMA grafting were each associated with increased risk of death (RD) from heart failure. Risk of death from heart failure (RD [women minus men] = 2.05; CI95%, 0.89 to 3.22) and hemorrhage (RD [women minus men] = 0.63; CI95%, 0.13 to 1.13) was greater among women; these accounted for 71.1% of the sex-specific difference in mortality rates. CONCLUSIONS Excess risk of hospital mortality among women having CABG was largely the consequence of death from heart failure and, to a lesser extent, from hemorrhage. Smaller BSA (probably because of its association with coronary artery luminal diameter) and the absence of IMA grafting were each associated with increased risk of death from heart failure.

ACC/AHA Guidelines for Coronary Artery Bypass Graft Surgery: Executive Summary and Recommendations A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Committee to Revise the 1991 Guidelines for Coronary Artery Bypass Graft Surgery)

The American College of Cardiology/American Heart Association (ACC/AHA) Task Force on Practice Guidelines was formed to make recommendations regarding the appropriate use of diagnostic tests and therapies for patients with known or suspected cardiovascular disease. Coronary artery bypass graft (CABG) surgery is among the most common operations performed in the world and accounts for more resources expended in cardiovascular medicine than any other single procedure. Since the original Guidelines were published in 1991, there has been considerable evolution in the surgical approach to coronary disease, and at the same time there have been advances in preventive, medical, and percutaneous catheter approaches to therapy. These revised guidelines are based on a computerized search of the English literature since 1989, a manual search of final articles, and expert opinion. As with other ACC/AHA guidelines, this document uses ACC/AHA classifications I, II, and III as summarized below: Class I: Conditions for which there is evidence and/or general agreement that a given procedure or treatment is useful and effective. Class II: Conditions for which there is conflicting evidence and/or a divergence of opinion about the usefulness or efficacy of a procedure. Class IIa: Weight of evidence/opinion is in favor of usefulness/efficacy. Class IIb: Usefulness/efficacy is less well established by evidence/opinion. Class III: Conditions for which there is evidence and/or general agreement that the procedure/treatment is not useful/effective and in some cases may be harmful. ### A. Hospital Outcomes Seven core variables (priority of operation, age, prior heart surgery, sex, left ventricular [LV] ejection fraction [EF], percent stenosis of the left main coronary artery, and number of major coronary arteries with significant stenoses) are the most consistent predictors of mortality after coronary artery surgery. The greatest risk is correlated with the urgency of operation, advanced age, and 1 or more prior coronary bypass surgeries. Additional variables that are related …

Identification of preoperative variables needed for risk adjustment of short-term mortality after coronary artery bypass graft surgery

OBJECTIVES The purpose of this consensus effort was to define and prioritize the importance of a set of clinical variables useful for monitoring and improving the short-term mortality of patients undergoing coronary artery bypass graft surgery (CABG). BACKGROUND Despite widespread use of data bases to monitor the outcome of patients undergoing CABG, no consistent set of clinical variables has been defined for risk adjustment of observed outcomes for baseline differences in disease severity among patients. METHODS Experts with a background in epidemiology, biostatistics and clinical care with an interest in assessing outcomes of CABG derived from previous work with professional societies, government or academic institutions volunteered to participate in this unsponsored consensus process. Two meetings of this ad hoc working group were required to define and prioritize clinical variables into core, level 1 or level 2 groupings to reflect their importance for relating to short-term mortality after CABG. Definitions of these 44 variables were simple and specific to enhance objectivity of the 7 core, 13 level 1 and 24 level 2 variables. Core and level 1 variables were evaluated using data from five existing data bases, and core variables only were examined in an additional two data bases to confirm the consensus opinion of the relative prognostic power of each variable. RESULTS Multivariable logistic regression models of the seven core variables showed all to be predictive of bypass surgery mortality in some of the seven existing data sets. Variables relating to acuteness, age and previous operation proved to be the most important in all data sets tested. Variables describing coronary anatomy appeared to be least significant. Models including both the 7 core and 13 level 1 variables in five of the seven data sets showed the core variables to reflect 45% to 83% of the predictive information. However, some level 1 variables were stronger than some core variables in some data sets. CONCLUSIONS A relatively small number of clinical variables provide a large amount of prognostic information in patients undergoing CABG.

Cancer: improving early detection and prevention. A community practice randomised trial.

OBJECTIVE--To test the impact of physician education and facilitator assisted office system interventions on cancer early detection and preventive services. DESIGN--A randomised trial of two interventions alone and in combination. SETTING AND SUBJECTS--Physicians in 98 ambulatory care practices in the United States. INTERVENTIONS--The education intervention consisted of a day long physician meeting directed at improving knowledge, attitudes, and skills relevant to cancer prevention and early detection. The office system intervention consisted of assistance from a project facilitator in establishing routines for providing needed services. These routines included division of responsibilities for providing services among physicians and their staff and the use of medical record flow sheets. MAIN OUTCOME MEASURES--The proportions of patients provided the cancer prevention and early detection services indicated annually according to the US National Cancer Institute. RESULTS--Based on cross sectional patient surveys, the office system intervention was associated with an increase in mammography, the recommendation to do breast self examination, clinical breast examination, faecal occult blood testing, advice to quit smoking, and the recommendation to decrease dietary fat. Education was associated only with an increase in mammography. Record review for a patient cohort confirmed cross sectional survey findings regarding the office system for mammography and faecal occult blood testing. CONCLUSION--Community practices assisted by a facilitator in the development and implementation of an office system can substantially improve provision of cancer early detection and preventive services.

Intraoperative Red Blood Cell Transfusion During Coronary Artery Bypass Graft Surgery Increases the Risk of Postoperative Low-Output Heart Failure

Background— Hemodilutional anemia during cardiopulmonary bypass (CPB) is associated with increased mortality during coronary artery bypass graft (CABG) surgery. The impact of intraoperative red blood cell (RBC) transfusion to treat anemia during surgery is less understood. We examined the relationship between anemia during CPB, RBC transfusion, and risk of low-output heart failure (LOF). Methods and Results— Data were collected on 8004 isolated CABG patients in northern New England between 1996 and 2004. Patients were excluded if they experienced postoperative bleeding or received ≥3 units of transfused RBCs. LOF was defined as need for intraoperative or postoperative intra-aortic balloon pump, return to CPB, or ≥2 inotropes at 48 hours. Having a lower nadir HCT was also associated with an increased risk of developing LOF (adjusted odds ratio, 0.90; 95% CI, 0.82 to 0.92; P=0.016), and that risk was further increased when patients received RBC transfusion. When adjusted for nadir hematocrit, exposure to RBC transfusion was a significant, independent predictor of LOF (adjusted odds ratio, 1.27; 95% CI, 1.00 to 1.61; P=0.047). Conclusions— In this study, we observed that exposure to both hemodilutional anemia and RBC transfusion during surgery are associated with increased risk of LOF, defined as placement of an intraoperative or postoperative intra-aortic balloon pump, return to CPB after initial separation, or treatment with ≥2 inotropes at 48 hours postoperatively, after CABG. The risk of LOF is greater among patients exposed to intraoperative RBCs versus anemia alone.

Cost-effectiveness of preoperative autologons donation in coronary artery bypass grafting

Concern about the safety of the allogeneic blood supply has made preoperative autologous blood donation (PAD) routine before major noncardiac operations. However, the costs and benefits of PAD in elective coronary artery bypass grafting (CABG) are not well established. We used decision analysis to (1) calculate the cost-effectiveness of PAD in CABG, expressed as cost per year of life saved, and (2) compare the health benefits of reducing allogeneic transfusions with the potential risks of autologous blood donation by patients with coronary artery disease. A prospective study of 18 institutions provided data on transfusion practice and blood product costs in CABG. On average, PAD in CABG costs

Sodium Bicarbonate Plus N-Acetylcysteine Prophylaxis: A Meta-Analysis

508,000 to

Long-Term Survival After Cardiac Surgery is Predicted by Estimated Glomerular Filtration Rate

909,000 per quality-adjusted year of life saved, depending on the number of units donated. Preoperative autologous blood donation is more cost-effective (as low as