These findings could have implications for practice, because the majority of perioperative MIs are asymptomatic, Dr. Cohn said. "Maybe we should, as the authors suggest, recommend routine troponins after high-risk surgery."
More frequent vital-sign monitoring; transfer to a unit with additional monitoring; and/or screening for hypoxia and anemia could be implemented in patients identified as high risk, Dr. Cohn said. Optimization of intravascular volume and initiation of cardiac medications are additional strategies. Also, closely monitored patients who experience an MI potentially could be transferred for cardiac catheterization or revascularization more quickly.
"It is thought provoking that we can change the management," Dr. Cohn said.
• HF, AF, and Cardiovascular Risk. Heart failure and atrial fibrillation should factor more prominently into cardiovascular risk stratification prior to noncardiac surgery, according to a population-based cohort study of more than 38,000 consecutive patients (Circulation 2011:124:289-96).
"There are many cardiovascular risk stratification tools available with quite a bit of variation. Coronary artery disease [CAD] is typically weighted heavily on most models," said Dr. Grant, director of perioperative and consultative medicine and member of the medicine faculty at the University of Michigan in Ann Arbor.
However, researchers found that ischemic and nonischemic heart failure and atrial fibrillation were more commonly associated with 30-day mortality and readmission rates than CAD in this large cohort, Dr. Grant said. The authors concluded that these risk factors are likely underestimated in current prediction models.
• Liberal vs. Conservative Blood Transfusion. "The hemoglobin level at which we decide to transfuse patients after surgery is controversial," Dr. Grant said, "and has not been adequately studied to date. Great variations in practice exist."
A randomized controlled trial of 2,016 hip fracture surgery patients found no significant difference between liberal and conservative postoperative blood transfusion policies in terms of mortality or ability to walk independently at 60 days for patients at high cardiovascular risk (N. Engl. J. Med. 2011;365:2453-62).
The liberal policy allowed transfusions to maintain hemoglobin at 10 g/dL. In contrast, patients randomized to a conservative approach could only be transfused if they had symptoms of anemia or at the physician’s discretion once hemoglobin was below 8 g/dL.
"Implications for practice, from my point of view, include some more evidence that maybe using more of a restrictive transfusion practice may be reasonable, including for higher-risk populations," Dr. Grant said. However, "red-cell transfusion practices still need to be individualized for your perioperative patient."
Dr. Smetana, Dr. Cohn, and Dr. Grant had no relevant financial disclosures.