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Directing certain bypass patients from low- to high-volume hospitals could balance clinical benefits with patient choice

Several studies have clearly shown that, when it comes to coronary artery bypass graft (CABG) surgeries, practice does make perfect, that is, hospitals that perform many CABG surgeries each year have better outcomes than hospitals that perform few such surgeries. Sending all patients to regional high-volume CABG hospitals could improve surgical outcomes, but it would also reduce patient access and choices. Targeted regionalization—that is, sending only patients at moderate or high surgical risk to high-volume CABG hospitals—could balance the clinical benefits of regionalization with patients' desires for choice and access, concludes a study supported by the Agency for Healthcare Research and Quality (National Research Service Award training grant T32 HS00053).

Brahmajee K. Nallamothu, M.D., M.P.H., of the University of Michigan Medical School, and colleagues assessed CABG outcomes at 56 U.S. hospitals using 1997 administrative and clinical data from a national outcomes database. They predicted in-hospital mortality rates classified into five groups based on surgical risk: minimal, low, moderate, high, and severe. They evaluated the outcomes of 2,029 patients who underwent CABG at 25 low-volume hospitals and 11,615 who underwent CABG at 31 high-volume hospitals. There were significant differences in mortality among patients hospitalized in low- and high-volume hospitals in patients at moderate (5.3 vs. 2.2 percent) and high risk (22.6 vs. 11.9 percent) but not in patients at minimal, low, or severe risk. Hospital costs and lengths of stay were similar across each of the five risk groups.

Based on these results, targeted regionalization of patients at moderate or high risk to high-volume hospitals would have resulted in an estimated 370 transfers and avoided 16 deaths. In contrast, full regionalization would have led to 2,029 transfers and avoided 20 deaths. The researchers conclude that targeted regionalization is likely to be a more acceptable option for patients, local providers, and hospitals.

See "The role of hospital volume in coronary artery bypass grafting: Is more always better?" by Dr. Nallamothu, Sanjay Saint, M.D., M.P.H., Scott D. Ramsey, M.D., Ph.D., and others, in the December 2001 Journal of the American College of Cardiology 38(7), pp. 1923-1930.

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