Cardiovascular Disease
Heart failure is one of the most common conditions requiring evaluation and treatment prior to noncardiac surgery. In stable asymptomatic patients undergoing low-risk surgery, preoperative assessment with electrocardiography (ECG), echocardiography, stress testing, chest radiographs, and cardiac catheterization is not necessary. Functional status is a reliable predictor of perioperative cardiac events; it can be assessed with a questionnaire such as the Duke Activity Status Index. If results from a recent stress test are not available, patients with good functional status are generally at low risk for a cardiac event in the perioperative period. However, if the patient shows clinical signs of decompensation, appropriate evaluation and management are indicated prior to surgery.
Coronary heart disease is a risk factor for perioperative myocardial ischemia, infarction, and death. However, even in patients with significant coronary heart disease, the risk of a major adverse cardiac event (MACE) is still low in patients undergoing low-risk surgery such as ophthalmic surgery. The goal of perioperative management of these patients is to minimize the risk of ischemic complications developing. Patients who have undergone percutaneous coronary intervention require treatment with dual antiplatelet therapy (DAT) with aspirin and P2Y12 inhibitors (eg, clopidogrel) to prevent a recurrent occlusion of the stented artery. See Chapter 5 in this volume for further discussion of heart disease.
Although hypertension is associated with an increased risk of perioperative complications, whether there is any benefit of lowering blood pressure (BP) in terms of risk reduction is unproven. Optimal blood pressure is also unclear, but the joint guidelines from the Association of Anaesthetists of Great Britain Ireland and the British and Irish Hypertension Society recommend a target BP below 160 mm Hg systolic and 100 mm Hg diastolic prior to elective surgery. The guidelines allow for patients with unknown preoperative blood pressures to undergo surgery with BP lower than 180 mm Hg systolic and lower than 110 mm Hg diastolic. In general, if patients are asymptomatic and have taken their BP medications, and their documented BP has typically been under 160/100 mm Hg prior to the day of surgery, then elective surgery may be performed regardless of the BP measurement on the morning of surgery. See Chapter 3 in this volume for further discussion of hypertension.
Atrial fibrillation is the most common sustained cardiac arrhythmia encountered in clinical practice. Atrial fibrillation increases the risk of death, heart failure, thromboembolic events, and hospital admissions. Patients with a history of stable atrial fibrillation do not require any preoperative specialized testing, but if the atrial fibrillation is newly onset, workup is recommended as well as delay of elective surgery. It is advisable to maintain medications for ventricular rate control, including their administration on the morning of surgery. If digoxin is used, obtaining preoperative blood levels is usually not necessary.
Excerpted from BCSC 2020-2021 series: Section 1 - Update on General Medicine. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.