What is the characteristic hemodynamic risk for patients with severe aortic stenosis during induction of anesthesia?

What is the characteristic hemodynamic risk for patients with severe aortic stenosis during induction of anesthesia?

• A. Increased heart rate is the primary risk.
• B. Decreased systemic vascular resistance is the primary risk.
• C. Hyperdynamic hypervolemic state.
• D. Inability to increase cardiac output; risk of hypotension; maintain sinus rhythm and cautious fluid management with vasopressors as needed.

Answer: (D)

In severe aortic stenosis, the left ventricle is stiff and outflow is fixed, so the ability to increase cardiac output in response to stresses is limited. During anesthesia induction, you often get vasodilation and myocardial depression, which can drop preload and systemic vascular resistance. Because the heart cannot significantly boost stroke volume to compensate, even a small drop in preload or afterload can cause a marked fall in arterial pressure. The safest course is to keep the heart in sinus rhythm to maximize diastolic filling time, provide careful fluid management to maintain preload without overloading the ventricle, and use vasopressors as needed to support afterload and perfusion. This combination directly addresses the main risk: an inability to increase cardiac output leading to hypotension. Tachycardia or reduced afterload from other causes are harmful but are not the primary issue in this scenario, and a hyperdynamic hypervolemic state is not typical of severe aortic stenosis.

In severe aortic stenosis, the left ventricle is stiff and outflow is fixed, so the ability to increase cardiac output in response to stresses is limited. During anesthesia induction, you often get vasodilation and myocardial depression, which can drop preload and systemic vascular resistance. Because the heart cannot significantly boost stroke volume to compensate, even a small drop in preload or afterload can cause a marked fall in arterial pressure. The safest course is to keep the heart in sinus rhythm to maximize diastolic filling time, provide careful fluid management to maintain preload without overloading the ventricle, and use vasopressors as needed to support afterload and perfusion. This combination directly addresses the main risk: an inability to increase cardiac output leading to hypotension. Tachycardia or reduced afterload from other causes are harmful but are not the primary issue in this scenario, and a hyperdynamic hypervolemic state is not typical of severe aortic stenosis.