Ch 25 Structure and Function of the cardiovascular system

A client has prominent jugular veins. What type of medical problem is associated with prominent jugular veins?

Right-sided heart failure Right-sided heart failure is seen with prominent jugular veins.

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

Nitric oxide

A client is having blood work done. What percentage of red blood cells represents the formed elements of the blood?

40 - 45% The red blood cells constitute 40 to 45 percent of the formed elements of the blood.

A client with a history of heart failure has the following echocardiogram results: heart rate 80 beats/minute; end-diastolic volume 120 mL; and end-systolic volume 60 mL. What is this client's ejection fraction (EF)?

50% Ejection fracture = stroke volume ÷ end-diastolic volume. Stroke volume equals the difference between end-diastolic and end-systolic volume. Therefore, EF = 60 ÷ 120, or 50%.

A client is admitted to the cardiac unit with a diagnosis of pericarditis. The nurse is teaching the client about the anatomical location of the infection. The nurse evaluates the effectiveness of the teaching when the client correctly identifies which of the following as the location of the pericardium?

A membranous sac that encloses the heart

When reviewing diagnostic test results and physical assessment data for a client with a history of stage II hypertension, which of the following would be of most concern to the nurse?

An ejection fraction of 40% This ejection fraction is below normal (normal is about 55% to 75%) and indicates a poor prognosis. This low ejection fraction is a result of the complications of long-standing hypertension.

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

Which inotropic drugs increase cardiac contractility by increasing the influx of free extracellular calcium ions in the vicinity of the actin and myosin filaments?

Cardiac glycosides The ions directly involved in the cardiac action potential are sodium, calcium, and potassium. Although cardiac muscle cells require calcium for contraction, they have a less well-defined sarcoplasmic reticulum for storing calcium than do skeletal muscle cells. Thus, cardiac muscle relies more heavily than skeletal muscle on an influx of extracellular calcium ions for contraction. Cardiac glycosides (e.g., digoxin) are inotropic drugs that increase cardiac contractility by increasing the free calcium concentration in the vicinity of the actin and myosin filaments.

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

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, nutrients, and wastes

Release of which humoral factors will result in vasodilation?

Histamine

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 Histamine has a powerful vasodilator effect on arterioles and has the ability to increase capillary permeability, allowing leakage of both fluid and plasma proteins into the tissues. Norepinephrine is a powerful vasoconstrictor. Serotonin causes vasoconstriction and plays a major role in control of bleeding. Prostaglandins produce either vasoconstriction or vasodilation.

Release of which humoral factors will result in vasodilation?

Histamine Histamine has a powerful vasodilator effect on arterioles and has the ability to increase capillary permeability, allowing leakage of both fluid and plasma proteins into the tissues. Norepinephrine, angiotensin II, and serotonin are all potent vasoconstrictors.

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

If a client experiences sympathetic nervous stimulation of the heart, the nurse will observe which changes in manifestations?

Increased heart rate and increased contractility The sympathetic nervous system has an excitatory influence on heart rate and contractility, and it serves as the final common pathway for controlling the smooth muscle tone of the blood vessels. With stimulation of sympathetic nervous system, both heart rate and contractility would increase.

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

Pressure pulses

Which of the following is true regarding pulmonary circulation?

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

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

Left ventricle

A nurse is assessing a female client and notes that her left arm is swollen from the shoulder down to the fingers, with non-pitting edema. The right arm is normal. The client had a left-sided mastectomy 1 year ago. What does the nurse suspect is the problem?

Lymphedema The lymphatic system filters fluid at the lymph nodes and removes foreign particles such as bacteria. When lymph flow is obstructed, a condition called lymphedema occurs. Involvement of lymphatic structures by malignant tumors and removal of lymph nodes at the time of cancer surgery are common causes of lymphedema.

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

Lymphedema in the affected arm

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

Pulmonary&Aortic Valve

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.

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

Stroke volume

During an assessment of a client with ankle swelling, the nurse observes jugular venous pulsations 5 cm above the sternal angle when the head of his bed is elevated 45 degrees. What is the correct interpretation of this finding?

The client has increased pressure related to right-sided heart The jugular veins are normally flat or collapsed. Since there are no valves at the atrial sites (i.e., venae cavae and pulmonary veins) where blood enters the heart, they can become prominent in severe right-sided heart failure. This means that excess blood is pushed back into the veins when the atria become distended.

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 In clinical practice, the measurement of the cardiac forms of troponin T and troponin I is used in the diagnosis of myocardial infarction. Troponin C is not diagnostic of a myocardial infarction. Troponin A is not one of the troponin complexes.

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.

In the circulatory system, pressure is inversely related to which factor?

Volume

If the parasympathetic neurotransmitter releases acetylcholine, the nurse should anticipate observing what changes in the ECG pattern

Which inotropic drugs increase cardiac contractility by increasing the influx of free extracellular calcium ions in the vicinity of the actin and myosin filaments?

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