Relationship Between Preventability of Death After Coronary Artery Bypass Graft Surgery and All-Cause Risk-Adjusted Mortality Rates

Abstract

Background-The goal of this study was to determine the relationship between all-cause, risk-adjusted, in-hospital mortality after coronary artery bypass graft surgery and the proportion of preventable in-hospital deaths as a measure of quality of care at an institution level. Methods and Results-We conducted a retrospective analysis of 347 randomly selected in-hospital deaths after isolated coronary artery bypass graft surgery at 9 institutions in Ontario over the period of 1998 to 2003. Nurse-abstracted chart summaries were reviewed by 2 experienced cardiac surgeons who were blinded to patient, surgeon, and hospital and used a standardized implicit tool to identify preventable death. A third reviewer reassessed all cases in which the first 2 reviewers disagreed. Rates of preventable deaths were estimated for each hospital and compared with all-cause mortality rates. A structured adverse event audit completed by each surgeon-reviewer was used to identify quality improvement opportunities for the preventable deaths. A total of 111 of 347 deaths (32%) were judged preventable despite a low risk-adjusted mortality range (1.3% to 3.1%) across hospitals. No significant correlation was found between all-cause, risk-adjusted in-hospital mortality rates and the proportion of preventable deaths at the hospital level (Spearman coefficient, Ϫ0.42; Pϭ0.26). A large proportion of preventable deaths were related to problems in the operating room (86%) and intensive care unit (61%). Many deaths were associated with deviations in perioperative care (32% based on concurrence of 2 reviewers, and another 42% in cases in which 1 reviewer reached that opinion). Conclusions-Approximately one third of in-hospital coronary artery bypass graft deaths were judged preventable by surgeon reviewers. All-cause risk-adjusted mortality rates are convenient measures of institutional quality of care but were not correlated with preventable mortality in our jurisdiction. Providers should conduct detailed adverse event audits to drive meaningful improvements in quality.

Public Reporting of 30-Day Mortality for Patients Hospitalized With Acute Myocardial Infarction and Heart Failure

“…A recent study in Ontario examined deaths among patients who underwent bypass surgery at various institutions. 9 Although the Ontario hospitals had favorable mortality rates, about a third of the deaths were deemed preventable had optimal care been provided. That analysis indicated opportunities for improvement in the care of these patients.…”

Publicly reported provider outcomes: The concerns of cardiac surgeons in a single-payer system

“…We are striving toward this goal by working with our stakeholders to develop and collect consensus quality measures with a rigorous independent data audit (25). In addition, rather than simply measuring outcome rates, our region will have provided more detailed independent feedback on how adverse outcomes relate to quality of care problems (26). We anticipate that providing clinically relevant feedback will provide a clearer roadmap to direct quality improvement activities.…”

Hospital standardized mortality ratios

“…However, process change represents the major aspect of health care delivery under providers' control. If hospital standardized mortality ratios correlate poorly with the need for process changes (as in the study by Dubois and colleagues and a recent study from Ontario 3 ), it remains unclear how hospital standardized mortality ratios can serve as a useful screen for quality problems.…”

“…Mooney and colleagues found that studies of nicotine replacement therapies are generally not blind in that participants correctly guess assignment at rates significantly above chance. 2 When this finding is combined with the meta-analytic finding by Eisenberg and colleagues that smoking cessation with pharmacologic treatment is nearly always more successful than cessation without pharmacologic treatment in clinical trials and the fact that cessation with pharmacological treatment has failed to be more successful than cessation without such treatment in nearly all of real-world surveys conducted to date, 3 it strongly suggests that the pharmacologic treatment of chemical dependency may be the only known research area in which blinding is impossible.…”