Preoperative evaluation

Question 1

Potential surgical complications

Answer 1

All surgeries involve some level of risk, and the evaluation allows the patient to balance the risks involved in surgery against the potential benefits, and allows the physician to minimize risks before, during, and after the procedure. Potential surgical complications involve infectious (wound infections, pneumonia, urinary tract infections, bacterial endocarditis, and sepsis), cardiac (myocardial infarction, cardiac arrest, pulmonary edema, and complications of congestive heart failure), pulmonary (pneumonia, atelectasis, bronchitis, respiratory failure), thrombosis (peripheral venous thromboembolism, arterial thrombosis) adverse reactions to anesthesia, gastrointestinal (ulcer disease, ileus, hyperemesis), and psychologic (delirium, exacerbation of existing psychiatric disease) complications. Cardiac events are the events that are most likely to be lethal. Pulmonary complications are most likely to be seen in children and are common in obese patients, but are less likely to be lethal.

Question 2

There are three categories of risk: high risk, moderate risk, and low risk procedures:

Answer 2

Low-risk procedures have a risk of cardiac death less than 1% and include breast surgery, cataract surgery, superficial dermatologic surgery, and endoscopy. They

generally do not require additional cardiac preoperative testing. Moderate-risk procedures have a risk of cardiac death between 1% and 5% and include carotid

endarterectomies, head and neck surgeries, intrathoracic and intraperitoneal surgeries, orthopedic surgeries, and prostate surgeries. High-risk procedures have high anticipated blood loss and include aortic or peripheral vascular surgery. They generally have a risk of cardiac death greater than 5%.

Question 3

Preoperative cardiac evaluation:

Answer 3

If a patient has no known heart disease, the evaluator should look at clinical predictors for heart disease. Major clinical predictors would require coronary artery evaluation prior to surgery, and include unstable coronary syndromes, decompensated congestive heart failure (CHF), significant arrhythmias, or severe valvular disease. Intermediate clinical predictors include mild angina, a prior MI, compensated CHF, diabetes, and renal insufficiency. Intermediate clinical predictors require the evaluator to look at the patient’s functional capacity to determine level of preoperative cardiac testing. In a patient with poor functional capacity, noninvasive testing is recommended.

Question 4

People with clinically important coronary artery disease

Answer 4

Recent coronary revascularization is a risk for poor perioperative outcomes. People with clinically important coronary artery disease should defer noncardiac procedures until 6 months after revascularization, when possible. If surgery is necessary within 6 months after revascularization, repeated evaluation of the coronary arteries is necessary prior to surgery.

Question 5

Asymptomatic patients who have had a normal stress test in the past 2 years, bypass surgery in the past 5 years, or angioplasty in the past 5 years…

Answer 5

Asymptomatic patients who have had a normal stress test in the past 2 years, bypass surgery in the past 5 years, or angioplasty in the past 5 years are unlikely to have developed significant new disease. Current recommendations are that these people may proceed to surgery without further cardiac workup. However, some experts suggest screening ECG should be done in patients older than 55 or with known cardiac disease.