Can the anesthesiologist affect outcome after CABG surgery? A study from New York

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Patients who received care from low-performance anesthesiologists, defined as anesthesiologists in the 25th percentile in the distribution of anesthesiologist risk adjusted outcomes, had an almost two-fold higher risk of death or serious complications than patients who received care from high-performing anesthesiologists, even when patients were stratified by their baseline preoperative risk. (Image source: Thinkstock)

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Back in the mid-1980s, there was a study (PMID 3970360) showing that postoperative myocardial infarction after coronary artery bypass graft (CABG) surgery was more likely in patients who had tachycardia. Most anesthesiologists probably have forgotten the primary finding, and remember the study for a specific detail: anesthesiologist #7. This anesthesiologist, not otherwise identified, had the highest incidence of intraoperative tachycardia, myocardial ischemia, and postoperative myocardial infarction. To this day anesthesiologist will refer to “anesthesiologist #7” as a derisive term for an error-prone colleague.

Anesthesia care has changed significantly since that time. However, the question remains whether a subset of anesthesiologists is particularly skilled relative to a different subset. That’s the “glass half full” question. You can invert that if you prefer the “glass half empty” question.

Dr. Laurent G. Glance, Department of Anesthesiology, University of Rochester School of Medicine, Rochester, New York, and RAND Health, RAND, Boston, Massachusetts, and colleagues used data from the New York State Cardiac Surgery Reporting System for patients undergoing isolated CABG surgery in New York State between 2009 and 2010 to see whether there was a difference in mortality and major complication outcomes across anesthesiologists. The results of their analysis are summarized in the article titled “The Impact of Anesthesiologists on Coronary Artery Bypass Graft Surgery Outcomes,” which was published in this month’s issue of Anesthesia & Analgesia.

The study group consisted of 7920 patients who underwent isolated CABG surgery. Ninety-one anesthesiologists and 97 surgeons in 23 New York State hospitals managed the cases. The authors found that variability across anesthesiologists was highly significant. Patients who received care from low-performance anesthesiologists, defined as anesthesiologists in the 25th percentile in the distribution of anesthesiologist risk adjusted outcomes, had an almost two-fold higher risk of death or serious complications than patients who received care from high-performing anesthesiologists, even when patients were stratified by their baseline preoperative risk. In addition, the relationship between anesthesiologist and surgeon risk-adjusted performance was poor.

What are the distinguishing characteristics of better performing anesthesiologists? To state that some are better than others is not particularly helpful; we likely all know that (whether we will admit to this in public or otherwise). In addition, if there is actually a volume-outcome relationship with regard to patient outcomes, this paper will have major policy implications. It is about time that we try to look at this issue more closely, especially given how many low-volume providers are present in the New York State database.

Dr. Bryan G. Maxwell, Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, and coauthors note in the accompanying editorial “Does It Matter Who the Anesthesiologist Is for My Heart Surgery?” that we should reject the widespread assumption that one anesthesiologist does not change patient outcome compared to another and accept that instead, which anesthesiologist performs a case matters a great deal. These findings will prompt us to investigate how anesthesiologists differ from one another in practices that affect patient outcomes and to define quality in relation to some unavoidable degree of inter-provider variability. They also raise questions about whether anesthesiologists’ outcomes should be publicized and whether patients should select an anesthesiologist based on that outcome data.

Overall this is a well-written paper and the conclusions are both interesting and provocative. Ever since “anesthesiologist #7,” we have wondered if there is an anesthesiologist effect on cardiac surgery outcomes. Now that we know “anesthesiologist #7” wasn’t an anomaly.

This paper may produce a storm of outcry since because half of us are below average by definition. We are watching the weather channel closely.