Predicted risk of cardiac complications varies among risk calculators
Background: A critical juncture in the American Heart Association/American College of Cardiology 2014 perioperative guidelines relies on clinicians categorizing patients undergoing noncardiac surgery as either low risk (less than 1%) or elevated risk (greater than or equal to 1%) for a MACE. The purpose of this study is to determine whether there is variability between the three risk calculators endorsed by the ACC/AHA guidelines as prediction tools to make this risk stratification.
Study design: Retrospective observational study.
Setting: National Surgical Quality Improvement Program database.
Synopsis: The NSQIP database was used to identify 10,000 patients who had undergone noncardiac surgery. The risk of MACE for each patient was then calculated using the Revised Cardiac Risk Index, the American College of Surgeons National Surgical Quality Improvement Program Surgical Risk Calculator, and the National Surgical Quality Improvement Program Myocardial Infarction or Cardiac Arrest calculator. Data were analyzed using the intraclass correlation coefficient and kappa analysis. Results demonstrated that 29% of the time the three calculators disagreed on which patients were classified as low risk. This suggests that, when following the ACC/AHA perioperative guidelines, a recommendation for further preoperative cardiac testing may depend on which risk prediction tool is used to calculate the risk of MACE.
Bottom line: Nearly one-third of the time, the three risk calculators recommended in the ACC/AHA 2014 perioperative guidelines do not agree on which patients are classified as low risk; this may affect clinical decision making for some patients.
Citation: Glance LG et al. Impact of the choice of risk model for identifying low-risk patients using the 2014 American College of Cardiology/American Heart Association perioperative guidelines. Anesthesiology. 2018;129(5):889-900.
Dr. Bordin-Wosk is an assistant clinical professor in the division of hospital medicine at the University of California, San Diego.
