Circulation: Most in-hospital CABG-related deaths are preventable
Approximately one-third of in-hospital CABG deaths are preventable by surgeon reviewers, according to a retrospective analysis published in the June 10 issue of Circulation.

Veena Guru, MD, from the Institute for Clinical Evaluative Sciences in Toronto, and colleagues wanted to determine the relationship between all-cause, risk-adjusted, in-hospital mortality after CABG surgery and the proportion of preventable in-hospital deaths as a measure of quality of care at the institution level.

The researchers retrospectively analyzed 347 randomly selected in-hospital deaths after isolated CABG surgery at nine institutions in Ontario over the period of 1998 to 2003. Then, two experienced cardiac surgeons who were blinded to patient, surgeon and hospital, reviewed the nurse-abstracted chart summaries, and used a standardized implicit tool to identify preventable death. A third reviewer reassessed all cases in which the first two reviewers disagreed, according to the authors.

The investigators estimated the rates of preventable deaths for each hospital and compared with all-cause mortality rates; and they used a structured adverse event audit completed by each surgeon-reviewer to identify quality improvement opportunities for the preventable deaths.

Guru and colleagues judged that a total of 111 out of 347 deaths (32 percent) were preventable, despite a low risk-adjusted mortality range (1.3 to 3.1 percent) across hospitals.

The researchers found no significant correlation between all-cause, risk-adjusted in-hospital mortality rates and the proportion of preventable deaths at the hospital level (Spearman coefficient, –0.42).

However, the authors noted that a large proportion of preventable deaths were related to problems in the operating room (86 percent) and intensive care unit (61 percent). Many deaths were associated with deviations in perioperative care (32 percent based on concurrence of two reviewers, and another 42 percent in cases in which one reviewer reached that opinion), according to the investigators.

Guru and colleagues concluded that all-cause risk-adjusted mortality rates are convenient measures of institutional quality of care, but were not correlated with preventable mortality in their jurisdiction.

Based on their findings, the researchers recommended that providers should conduct detailed adverse event audits to drive meaningful improvements in quality.