Pathophysiology Chapter 25

The cardiac reserve refers to the maximum percentage of increase in cardiac output that can be achieved above the normal resting level. What is the normal young adult's percentage cardiac reserve?

300% - 400%

The heart consists of four valves. Which are the semilunar valves? Select all that apply.

Aortic and pulmonary

A client is diagnosed with an abdominal aortic aneurysm that the physician just wants to "watch" for now. When teaching the client about signs/symptoms to watch for, the nurse will base the teaching on which physiologic principle?

As the aneurysm grows, more tension is placed on the vessel wall, which increases the risk for rupture.

A client's echocardiogram identified a narrowed valve that has resulted in a decreased blood flow between the left atria and left ventricle. The nurse would interpret this as the:

Bicuspid valve

Cardiac output (CO) is used to measure the efficiency of the heart as a pump. What is the equation used to express CO?

CO = SV X HR. The efficiency of the heart as a pump often is measured in terms of cardiac output (CO) or the amount of blood the heart pumps each minute. The CO is the product of the stroke volume (SV) and the heart rate (HR), and can be expressed by the equation: CO = SV X HR. AV stands for atroventricular and EF stands for ejection fraction. Neither is part of the equation for CO.

Select the correct sequence of blood return to the heart.

Capillaries, venules, veins, right atrium

Based on assessment, a nurse suspects the client may be experiencing heart failure. Which diagnostic test would be the best indicator to determine pressure being exerted on the right side of the heart?

Central venous pressure

The heart controls the direction of blood flow. What is the role of the aortic valve?

Controls the direction of blood flow from the left side of the heart to the systemic circulation

When intracranial pressure (ICP) equals intra-arterial pressure, the central nervous system ischemic response is initiated. This response is directed at raising arterial pressure above ICP, thereby reestablishing blood flow to the vasomotor center of the brain. What is this response called?

Cushing reflex

A client is experiencing a sudden increase in heart rate resulting in less time in diastole. This can result in which potential complication?

Decreased stroke volume

A grandmother who works as a cook at a nearby school was recently hospitalized when she lost an extensive amount of blood in a work-related accident. The grandmother tells the nurse that she heard that she would keep feeling faint until the brain made more blood. The nurse knows that when the blood pressure dropped, the pressure in the carotid arteries decreased. This was detected by baroreceptors in the carotid arteries. What did the baroreceptors do?

Increase sympathetic stimulation of the heart and blood vessels

A client took a weight loss drug that activated the alpha-adrenergic receptors in the sympathetic nervous system. Which manifestations would the nurse expect to occur? Select all that apply.

Increased blood pressure of cardiac contraction Increased cardiac cycle speed

Which related circulatory complication can result from surgical treatment for metastatic breast cancer?

Lymphedema in the affected arm

A nurse is teaching a client the correct technique for taking an arterial pulse. The nurse explains that the pulsations are:

Pressure pulses

When a client is experiencing a parasympathetic nervous system response to severe chest pain, the nurse will likely see which change in the client's vital signs?

Pulse rate below 59 beats/minute

The difference between the end-diastolic and end-systolic volumes is called what?

Stroke volume

The nurse is reviewing the circulatory system. Which statements are correct about the functional organization of the circulatory system? Select all that apply.

The arterial system distributes oxygenated blood to the tissues. The venous system collects deoxygenated blood from the tissues.

Humoral control of blood flow involves the effect of vasodilator and vasoconstrictor substances in the blood. Select the factor that has a powerful vasodilator effect on arterioles and increases capillary permeability.

histamine

The troponin complex is one of a number of important proteins that regulate actin-myosin binding. Troponin works in striated muscle to help regulate calcium-mediated contraction of the muscle. Which of the troponin complexes is diagnostic of a myocardial infarction?

Troponin T and troponin I

The nurse identifies the blood vessel layer that constricts to regulate and control diameter as:

Tunica media

Preload, the stretch on the heart before contraction, is largely determined by which factor?

Venous blood return

A client has a blood pressure of 68/38 mm Hg and fainted after donating a unit of blood. The client is experiencing low preload from loss of blood volume. What is preload?

Venous return to the heart

The cardiac cycle describes the pumping action of the heart. Which statement is correct about systole?

Ventricles contract and blood is ejected from the heart.

The school nurse is doing a health class on the functional organization of the circulatory system. What is the function of the capillaries in the circulatory system?

exchange gases and nutrients/wastes

Which of the following blood flow patterns reduces friction, allowing the blood layers to slide smoothly over one another?

laminar

The heart is a four-chambered pump. Which chamber of the heart pumps blood into the systemic circulation?

left ventricle

Nitroglycerin is the drug of choice in treating angina. What does nitroglycerin release into the vascular smooth muscle of the target tissues?

nitric oxide

The heart is a four-chambered pump. What is the function of the right ventricle?

pumps blood to the lungs

Which sequence is the correct pathway for blood flow through the heart?

right atrium - tricuspid valve - right ventricle - pulmonary artery - lungs - pulmonary vein - left atrium - mitral valve - left ventricle - aorta

The heart consists of four valves. Which are the heart's atrioventricular valves? Select all that apply.

tricuspid and mitral

A nurse working with a client in heart failure is explaining why the symptoms of the heart failure were not evident for a long period of time. When describing the Frank-Starling mechanism, the nurse will explain:

the relationship between venous return and stroke volume

A client asks why he has not had major heart damage since his cardiac catheterization revealed he has 98% blockage of the right coronary artery. The nurse's best response is:

"You have small channels between some of your arteries, so you can get blood from a patent artery to one severely blocked."

A client has just experienced stimulation of the vagus nerve. Which sign would the nurse anticipate the client to manifest?

Decreased heart rate

Which structure within the myocardium contains gap junctions that allow impulses to travel rapidly so the heart can contract as a single unit?

Intercalated disks

Which of the following is true regarding pulmonary circulation?

It is a low-pressure system that allows for improved gas exchange.

Which blood vessel layer is made primarily of muscle?

Tunica media

Which neurotransmitter is associated with the parasympathetic nervous system?

acetylcholine