The American College of Cardiology and the American Heart Association have established a set of guidelines, written by a consortium of physicians involved in the perioperative care of patients undergoing noncardiac surgery. These guidelines are a tool to help health-care providers assess risk and administer therapies that will optimize both outcomes and cost. Quality preoperative evaluations take into consideration patient risk factors and preexisting conditions, and order appropriate tests based on peer-reviewed evidence.
In the development of these guidelines, the authors classified each recommendation on the strength of the underlying studies:
Class I: There exists evidence or general agreement that treatment or procedure is of useful and/or effective. Procedure/Treatment should be performed.
Class II: Conditions with conflicting evidence and/or controversy with regard to usefulness/efficacy of a procedure or therapy.
Class IIa: The amount of evidence and general opinion demonstrate that benefits likely outweigh risks; however, additional studies with focused objectives are still needed. It is reasonable to perform procedure/administer treatment.
Class IIb: Evidence and general opinion suggests a possible benefit with procedure/treatment. Additional studies with larger populations, and broad objectives are needed. A procedure or treatment may be considered.
Class III: Consensus agreement with respect to procedure or treatment is of no use or ineffective or can cause harm.
FURTHER PREOPERATIVE TESTING TO ASSESS CORONARY RISK
The history, physical examination, and electrocardiogram should focus on identifying preexisting cardiac abnormalities, such as symptomatic arrhythmias, coronary artery disease (CAD), prior myocardial infarction (MI), heart failure (HF), implantable cardiac devises, or a history of orthostatic instability. If abnormalities are identified, problems need to be ranked in order of severity, disability, and treatments.
An algorithm-based approach to preoperative evaluation was developed to assess CAD in a cost-effective manner (Figure 62-1). This algorithm is based on clinical markers, previous coronary evaluations/treatments, functional capacity, and risk stratification commensurate with various types of surgery.
Cardiac evaluation and care algorithm for noncardiac surgery based on active clinical conditions, known cardiovascular disease, or cardiac risk factors for patients 50 years of age or more. (Reproduced with permission from Fleisher L et al. ACC/AHA 2007 Guidelines on perioperative cardiovascular evaluation and care for noncardiac surgery: executive summary. Circulation. 2007;116(17):1971-1996.)
Clinical markers—Major clinical predictors associated with increased perioperative cardiovascular hazard include: acute coronary syndrome (ACS) such as acute MI (<7 days before procedure), unstable or severe angina, decompensated HF, symptomatic arrhythmias, or severe valvular disease.
Intermediate clinical predictors of increased cardiac risk include: mild angina, history of MI (>1 month before procedure), compensated HF, preoperative creatinine greater than or equal to 2.0 mg/dL, and diabetes mellitus.
Minor clinical risk predictors include: advanced age, abnormal ECG, rhythm other than sinus, low functional capacity, history of ...