According to a study recently published in Circulation, among patients having coronary artery bypass surgery, even those who are considered "low-risk" have a significantly better chance of surviving if they have their surgery in high-volume institutions. In this study, investigators examined data from 57,000 bypass surgery patients who were registered in the New York State Cardiac Reporting System. They compared the odds of surviving the surgical hospitalizations with the number of bypass operations performed yearly in each institution. Their analysis concluded that, among "low-risk" bypass patients (i.e., those whose predicted surgical mortality was less than 2%,) those who had their surgery in institutions doing at least 200 bypass operations per year had a 47% reduction in in-hospital mortality, compared to patients whose surgery was performed in lower volume hospitals.
The risk of death for patients whose operative risk was considered moderate or high was also significantly reduced in high-volume institutions - but this finding was known already. What is new in this study is the finding that even low-risk patients benefited by having their operations performed in busy hospitals.
The investigators who published this study are quick to say their report does not mean that low-risk patients should be transferred to high-volume hospitals for their bypass surgery. What it means, instead, is that efforts should be made to identify why these patients do better in high-volume institutions, then apply that knowledge to the lower-volume institutions.
What this means in real life
DrRich agrees that we ought to find out why patients do better in high-volume institutions. Much of that difference may indeed not be related to the experience of the surgeons themselves, but may instead be related to differences in post-operative care processes and other features that could conceivably be transferable to low-volume hospitals.
DrRich further notes that it would be considered highly inflammatory for the authors of this report, or any other prominent members of the cardiology community, to call publicly for patients to have their bypass surgery only in larger, high-volume institutions. Everybody - even patient advocacy groups - would find such statements to be self-serving (since prominent cardiologists almost always practice in the high-volume places).
However, if DrRich needed bypass surgery today, he would not wait for more studies to tease out the reasons for the better outcomes seen in big institutions, and for these reasons to be translated into processes that could be applied in smaller institutions, then for the actual implementation of these processes. No. He would go to one of the places where outcomes already excel, as politically incorrect as this might be.