A nurse is discussing heart failure with a group of nursing students. Which statement by a student reflects an understanding of how compensatory mechanisms can compound existing problems in patients with heart failure?
A) "An increase in arteriolar tone to improve tissue perfusion can decrease resistance."
B) "An increase in contractility to increase cardiac output can cause pulmonary edema."
C) "When the heart rate increases to increase cardiac output, it can prevent adequate filling of the ventricles."
D) "When venous tone increases to increase ventricular filling, an increase in arterial pressure occurs."

Question

Quizplus · Accepted Answer

The heart rate increases to improve cardiac output, but it may prevent adequate ventricular filling. An increase in arteriole tone not only improves tissue perfusion but also increases both the resistance to the pumping of the heart and the cardiac workload. Increased contractility helps improve cardiac output but is detrimental because it increases the oxygen demand of the heart. An increase in venous tone improves ventricular filling, but as the ventricles fail, blood can back up and cause pulmonary edema.

A Nurse Is Discussing Heart Failure with a Group of Nursing