N88-Chapter 25: Structure and Function of the Cardiovascular System
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: A) "You must have been taking a blood thinner for a long time." B) "You have small channels between some of your arteries, so you can get blood from a patent artery to one severely blocked." C) "You are just a lucky person since most people would have had a massive heart attack by now." D) "With this amount of blockage, your red blood cells get through the vessel one by one and supply oxygen to the muscle."
"You have small channels between some of your arteries, so you can get blood from a patent artery to one severely blocked."
The heart is a four-chambered muscular pump. In one day, how many gallons of blood are pumped throughout the body? A-1500 B-1600 C-1700 D-1800
1800 >>In one day, this pump moves more than 1800 gallons of blood throughout the body.
A client is lying in a recumbent position. In this client, approximately how much total blood volume is in the central circulation? A-15% - 20% B-20% - 25% C-25% - 30% D-30% - 35%
25% - 30% >>In the recumbent position, approximately 25 to 30 percent of the total blood volume is in the central circulation.
A client is lying in a recumbent position. In this client, approximately how much total blood volume is in the central circulation? A- 15% - 20% B- 20% - 25% C- 25% - 30% D- 30% - 35%
25% - 30% RAITONALE: In the recumbent position, approximately 25 to 30 percent of the total blood volume is in the central circulation.
A client has suffered chest injuries following a automobile accident. The chest injury has resulted in an increase in intrathoracic pressure. There can be a transient shift from the pulmonary to the systemic circulation of how much blood? 150 mL 200 mL 250 mL 300 mL
250 mL >>An increase in intrathoracic pressure, which impedes venous return to the right heart, can produce a transient shift from the pulmonary to the systemic circulation of as much as 250 mL of blood.
The linear velocity of blood flow in the circulatory system varies widely. What is the linear velocity in the aorta? 20 to 25 cm/second 30 to 35 cm/second 40 to 45 cm/second 50 to 55 cm/second
30 to 35 cm/second >>The linear velocity of blood flow in the circulatory system varies from 30 to 35 cm/second in the aorta.
A client is having blood work done. What percentage of red blood cells represents the formed elements of the blood? 30 - 35% 40 - 45% 50 - 55% 60 - 65%
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)? A-2 mL B-50% C-0.80 D-180 mL
50% RAITONALE: 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 with heart disease has the left ventricular ejection fraction measured. What is the normal left ventricular ejection when determined by angiocardiography? 35% - 55% 45% - 65% 55% - 75% 65% - 85%
55% - 75% >>The normal left ventricular ejection fraction is usually 55 percent to 75 percent when determined by angiocardiography.
A client with heart disease has the left ventricular ejection fraction measured. What is the normal left ventricular ejection when determined by angiocardiography? A-35% - 55% B-45% - 65% C-55% - 75% D-65% - 85%
55% - 75% RATIONALE: The normal left ventricular ejection fraction is usually 55 percent to 75 percent when determined by angiocardiography.
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- The outer muscular layer of the heart B- The innermost lining of the heart chambers C- A membranous sac that encloses the heart D- The electrical conduction system of the heart
A membranous sac that encloses the heart RATIONALE: The pericardium forms a fibrous covering around the heart, holding it in a fixed position in the thorax and providing physical protection and a barrier to infection. The pericardium is a tri-layer sac consisting of a tough, outer fibrous layer and a thin, inner serous layer.
Valves in the veins prevent retrograde flow. In which veins are there no valves? Select all that apply. A-Abdominal B-Femoral C-Carotid D-Thoracic
Abdominal Thoracic RATIONALE: There are no valves in the abdominal or thoracic veins. Therefore, pressure in the abdominal and thoracic cavities heavily influence blood flow in these veins.
Which neurotransmitter is associated with the parasympathetic nervous system? A-Acetylcholine B-Dopamine C-Norepinephrine D-Epinephrine
Acetylcholine >>The actions of the autonomic nervous system are mediated by chemical neurotransmitters. Acetylcholine is the postganglionic neurotransmitter for parasympathetic neurons and norepinephrine is the main neurotransmitter for postganglionic sympathetic neurons. Sympathetic neurons also respond to epinephrine, which is released into the bloodstream by the adrenal medulla. The neurotransmitter dopamine can also act as a neurotransmitter for some sympathetic neurons.
Which neurotransmitter is associated with the parasympathetic nervous system? A) Acetylcholine B) Dopamine C) Norepinephrine D) Epinephrine
Acetylcholine RATIONALE: The actions of the autonomic nervous system are mediated by chemical neurotransmitters. Acetylcholine is the postganglionic neurotransmitter for parasympathetic neurons and norepinephrine is the main neurotransmitter for postganglionic sympathetic neurons. Sympathetic neurons also respond to epinephrine, which is released into the bloodstream by the adrenal medulla. The neurotransmitter dopamine can also act as a neurotransmitter for some sympathetic neurons.
A client diagnosed with secondary hypertension has begun to experience manifestations that are consistent with decreased cardiac output. Which determinants of cardiac output is hypertension most likely to affect directly? A) Preload B) Afterload C) Contractility D) Heart rate
Afterload
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? A-An ejection fraction of 40% B-Blood pressure of 146/80 C-Point of maximum impulse is located midclavicular at the 5th intercostal space D-A heart rate (HR) of 62 beats/minute
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.
When a client experiences the Cushing reflex, what occurs with the body? A-An increase in arterial pressure to levels above the intracranial pressure B-The systemic blood pressure decreases to restore equal amounts of oxygen throughout the body. C-The pupils contract in response to light exposure. D-The toes fan outward in response to stimulation being applied to the bottom of the foot.
An increase in arterial pressure to levels above the intracranial pressure >>This reflex produces a rise in arterial pressure to levels above intracranial pressure so that the blood flow to the vasomotor center can be reestablished. Pupil contraction (papillary response) and the toe fanning (positive Babinski) do not relate with the Cushing reflex; neither does the oxygen supply to the body.
An increase in venous return stimulates what mechanism within the heart? A-A decrease in blood pressure B-An increase in oxygen consumption C-A decrease in cardiac output D-An increase in heart rate
An increase in heart rate >>An increase in venous return stimulates right atrial stretch receptors that initiate an increase in heart rate. The other assessments are not found with increased venous return. An increase in blood pressure and increase in cardiac output are found.
A nurse is reviewing an echocardiogram for a client with a congenital defect in the papillary muscles of the heart. Based on this result, which assessment should the nurse complete? A-Auscultate for an extra heart sound due to incomplete semilunar valve closure. B-Auscultate for a murmur caused by the backward expulsion of blood through the atrioventricular valves. C-Palpate the pericardium for a heave or thrill. D-Monitor the blood pressure.
Auscultate for a murmur caused by the backward expulsion of blood through the atrioventricular valves >>When closed, the AV valves prevent backflow of blood from the ventricles to the atria during systole. The AV valves are supported by the papillary muscles, which project from the wall of the ventricles. Contraction of the papillary muscles at the onset of systole ensures closure by producing tension on the leaflets of the AV valves before the full force of ventricular contraction pushes against them.
During a physical examination of a client, the nurse palpates the point of maximal impulse (PMI) in the seventh intercostal space lateral to the left midclavicular line. What is the most appropriate action for the nurse to take? A-Assess the client for symptoms of left ventricular hypertrophy. B-Document that the PMI is in the normal anatomic location. C-Auscultate both of the carotid arteries for the presence of a bruit. D-Notify the physician.
Assess the client for symptoms of left ventricular hypertrophy. >>When the hand is placed on the thorax, the main impact of the heart's contraction is felt against the chest wall at a point between the fifth and sixth ribs, a little below the nipple and approximately 3 inches to the left of the midline. This is called the point of maximum impulse (PMI). A PMI located outside these landmarks indicates possible cardiac enlargement, such as with left ventricular hypertrophy.
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: A-Tricuspid valve B-Pulmonic valve C-Bicuspid valve D-Aortic valve
Bicuspid valve >>The bicuspid valve (also called the mitral valve) controls the flow of blood between the left atria and left ventricle. The aortic valve controls flow between the left ventricle and aorta. The tricuspid controls the flow between the right atria and ventricle. The pulmonic valve controls flow between the right ventricle and pulmonary artery.
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: A) Tricuspid valve B) Pulmonic valve C) Bicuspid valve D) Aortic valve
Bicuspid valve RATIONALE: The bicuspid valve (also called the mitral valve) controls the flow of blood between the left atria and left ventricle. The aortic valve controls flow between the left ventricle and aorta. The tricuspid controls the flow between the right atria and ventricle. The pulmonic valve controls flow between the right ventricle and pulmonary artery.
Which blood vessels function without the benefit of having walls comprised of three muscular layers? A-Capillaries B-Veins C-Arteries D-Arterioles
Capillaries RAITONALE: The capillaries are small, thin-walled vessels that link the arterial and venous sides of the circulation and allow the exchange of oxygen and metabolites generated by the various tissues. The walls of all blood vessels, except the capillaries, are composed of three layers: tunica externa, tunica media, and tunica intima.
Select the correct sequence of blood return to the heart. A-Capillaries, venules, veins, right atrium B-Capillaries, arterioles, arteries, right atrium C-Capillaries, arterioles, veins, left atrium D-Capillaries, venules, veins, left atrium
Capillaries, venules, veins, right atrium >>The correct pathway for blood returning back to the heart is the capillaries, venules, veins, and right atrium. The other options do not support normal blood flow.
Select the correct sequence of blood return to the heart. A) Capillaries, venules, veins, right atrium B) Capillaries, arterioles, arteries, right atrium C) Capillaries, arterioles, veins, left atrium D) Capillaries, venules, veins, left atrium
Capillaries, venules, veins, right atrium RATIONALE: The correct pathway for blood returning back to the heart is the capillaries, venules, veins, and right atrium. The other options do not support normal blood flow.
The heart controls the direction of blood flow. What is the role of the aortic valve? A-Controls the direction of blood flow from the atria to the ventricles B-Controls the direction of blood flow from the left side of the heart to the lungs C-Controls the direction of blood flow from the left side of the heart to the systemic circulation D-Controls the direction of blood flow from the ventricles to the atria
Controls the direction of blood flow from the left side of the heart to the systemic circulation >>The heart valves control the direction of blood flow from the atria to the ventricles (the AV valves), from the right side of the heart to the lungs (pulmonic valves) and from the left side of the heart to the systemic circulation (aortic valve).
The heart controls the direction of blood flow. What is the role of the aortic valve? A) Controls the direction of blood flow from the atria to the ventricles B) Controls the direction of blood flow from the left side of the heart to the lungs C) Controls the direction of blood flow from the left side of the heart to the systemic circulation D) Controls the direction of blood flow from the ventricles to the atria
Controls the direction of blood flow from the left side of the heart to the systemic circulation RATIONALE: The heart valves control the direction of blood flow from the atria to the ventricles (the AV valves), from the right side of the heart to the lungs (pulmonic valves) and from the left side of the heart to the systemic circulation (aortic valve).
The heart valves control the direction of blood flow. What is the function of the pulmonic valve? A-Controls the direction of blood flow from the right side of the heart to the lungs B-Controls the direction of blood flow from the left side of the heart to the lungs C-Controls the direction of blood flow from the right side of the heart to the systemic circulation D-Controls the direction of blood flow from the left side of the heart to the systemic circulation
Controls the direction of blood flow from the right side of the heart to the lungs RAITONALE: The heart valves control the direction of blood flow from the atria to the ventricles (the AV valves), from the right side of the heart to the lungs (pulmonic valve), and from the left side of the heart to the systemic circulation (aortic valve).
A client has just experienced stimulation of the vagus nerve. Which sign would the nurse anticipate the client to manifest? A-Decreased heart rate B-Increased cardiac contractility C-Increased heart rate D-Decreased blood coagulation
Decreased heart rate >> The neural control of the circulation occurs primarily through the sympathetic (SNS) and parasympathetic (PNS) divisions of the autonomic nervous system (ANS). The ANS contributes to the control of cardiovascular function through modulation of cardiac function (i.e., heart rate and cardiac contractility) and peripheral vascular resistance. Increased vagal activity (activation of the PNS) produces a slowing of heart rate. Increased cardiac contractility and heart rate refer to SNS stimulation. Blood coagulation is not affected by the autonomic nervous system.
A client is experiencing a sudden increase in heart rate resulting in less time in diastole. This can result in which potential complication? A-Increased blood viscosity B-Loss of action potential C-Decreased stroke volume D-Reduced cardiac contractility
Decreased stroke volume >>The time spent in diastole and filling of the ventricles becomes shorter as the heart rate increases. This leads to a decrease in stroke volume and, at high heart rates, may produce a decrease in cardiac output. Increased heart rate does not typically cause increased blood viscosity, a loss of action potential, or reduced cardiac contractility.
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? A-Distribute oxygenated blood to the tissues B-Collect deoxygenated blood from the tissues C-Exchange gases, nutrients, and wastes D-Pump blood
Exchange gases, nutrients, and wastes >>The circulatory system consists of the heart, which pumps blood; the arterial system, which distributes oxygenated blood to the tissues; the venous system, which collects deoxygenated blood from the tissues and returns it to the heart; and the capillaries, where exchange of gases, nutrients, and waste takes place.
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? A) Distribute oxygenated blood to the tissues B) Collect deoxygenated blood from the tissues C) Exchange gases, nutrients, and wastes D) Pump blood
Exchange gases, nutrients, and wastes RATIONALE: The circulatory system consists of the heart, which pumps blood; the arterial system, which distributes oxygenated blood to the tissues; the venous system, which collects deoxygenated blood from the tissues and returns it to the heart; and the capillaries, where exchange of gases, nutrients, and waste takes place.
Which compensatory mechanism is associated with long term regulation of blood flow? A-DNA B-RNA C-Fibroblast growth factor D-Serotonin
Fibroblast growth factor >>Fibroblast growth factors participate in the regulation of blood flow, which is a compensatory mechanism to decrease oxygen debt. Serotonin is liberated from aggregating platelets during the clotting process and causes vasoconstriction. DNA is a self-replicating material which is present in nearly all living organisms as the main constituent of chromosomes. It is the carrier of genetic information. RNA acts as a messenger carrying instructions from DNA for controlling the synthesis of proteins, although in some viruses RNA rather than DNA carries the genetic information.
Release of which humoral factors will result in vasodilation? A-Norepinephrine B-Angiotensin II C-Serotonin D-Histamine
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.
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. A-Norepinephrine B-Serotonin C-Prostaglandins D-Histamine
Histamine RATIONALE: 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? A- Norepinephrine B- Angiotensin II C- Serotonin D- Histamine
Histamine RATIONALE: 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 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. A-Increased blood pressure of cardiac contraction B-Decreased myocardial contraction C-Decrease in respiration rate D-Increased cardiac cycle speed
Increased blood pressure of cardiac contraction Increased cardiac cycle speed >>Sympathetic nervous system control of vascular smooth muscle tone occurs through receptor-activated opening and closing of the calcium channels. In general, alpha adrenergic receptors are excitatory in that they cause the channels to open and produce vasoconstriction. Increased sympathetic activity produces an increase in the heart rate, BP and the velocity and force of cardiac contraction.
If a client experiences sympathetic nervous stimulation of the heart, the nurse will observe which changes in manifestations? A) Increased heart rate and increased contractility B) Increased heart rate and decreased contractility C) Decreased contractility and decreased heart rate D) Decreased rate and force of contraction
Increased heart rate and increased contractility RATIONALE: 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.
Which factor can cause turbulent blood flow? A-Increased velocity B-Short vessel length C-High blood viscosity D-Layering of blood cells
Increased velocity >>Under some conditions, blood flow switches from laminar flow (blood component layering) to turbulent flow. Turbulence can result from an increase in velocity of flow, a decrease in vessel diameter, or low blood viscosity. Vessel length affects the rate of flow rather than the type of flow.
The lymph system correlates with the vascular system without actually being a part of the vascular system. Among other things, the lymph system is the main route for the absorption of fats from the gastrointestinal system. The lymph system empties into the right and left thoracic ducts, which are the points of juncture with the vascular system. What are these points of juncture? A-The bifurcation of the common carotid arteries B-The internal and external jugular veins C-Junctions of the subclavian and internal jugular veins D-The junction of the subclavian and the pulmonary veins
Junctions of the subclavian and internal jugular veins >>The lymph capillaries drain into larger lymph vessels that ultimately empty into the right and left thoracic ducts. The thoracic ducts empty into the circulation at the junctions of the subclavian and internal jugular veins. The lymphatic system only joins the vascular system in one place, so no other answer is accurate.
Which of the following blood flow patterns reduces friction, allowing the blood layers to slide smoothly over one another? A) Laminar B) Turbulent C) Crosswise D) Axially
Laminar RATIONALE: Laminar blood flow reduces friction by allowing the blood layers to slide smoothly over one another, with the axial layer having the most rapid rate of flow. Axially, crosswise, and turbulent blood flow would result in increased friction. In turbulent flow, the laminar stream is disrupted and the flow becomes mixed, moving radially (crosswise) and axially (lengthwise).
When the semilunar valves open it signals the onset of the ejection period. The aortic pressure reflects changes in the ejection of blood from which part of the heart? A-Right ventricle B-Left ventricle C-Right atrium D-Left atrium
Left ventricle >>The aortic pressure reflects changes in the ejection of blood from the left ventricle, not the right ventricle or atrium.
The heart is a four-chambered pump. Which chamber of the heart pumps blood into the systemic circulation? A- Right atrium B- Left atrium C- Right ventricle D- Left ventricle
Left ventricle RATIONALE: The right atrium receives blood returning to the heart from the system circulation. The left atrium receives oxygenated blood from the lungs. The right ventricle pumps blood to the lungs. The left ventricle pumps blood into the systemic circulation.
Which organ has larger capillary pores to allow the exchange of gases, nutrients, and/or waste products? A-Blood-brain barrier B-Kidney C-Liver D-Brain
Liver >>Liver capillaries have large pores so that substances can pass easily through the capillary wall, whereas the kidney has glomerular capillaries with fenestrations that assist with filtration. The brain has no involvement with the exchange of waste products.
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? A-Venous stasis B-Lymphedema C-Arteriosclerosis D-Deep vein thrombosis
Lymphedema RAITONALE: 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? A) Lymphedema in the affected arm B) Hypotension upon standing C) Tachycardia when at rest D) Irregular heart rate
Lymphedema in the affected arm RATIONALE: Involvement of lymphatic structures by malignant tumors and removal of lymph nodes at the time of cancer surgery are common causes of lymphedema. The other options are not related to the surgery that would have removed any affected lymph nodes.
The pericardium is a tri-layer sac. Which layer prevents acute dilation of the heart chambers and exerts a restraining effect on the left ventricle? A-Outer fibrous layer B-Inner serous layer C-Visceral layer D-Parietal layer
Outer fibrous layer >>The outer fibrous layer prevents acute dilation of the heart chambers. The inner serous layer consists of a visceral layer and a parietal layer.
Which factor represents the amount of blood that the heart must pump with each beat and is determined by the stretch of the cardiac muscle fibers and the actions of the heart prior to cardiac contraction? A-Preload B-Afterload C-Cardiac contractility D-Heart rate
Preload >>Preload is the distending force that stretches the heart muscle just prior to the work of the onset of ventricular contraction. It represents the volume of blood stretching the ventricular muscle fibers at the end of diastole (i.e., end-diastolic volume) and is the sum of the blood remaining in the heart at the end of systole (end-systolic volume) and the venous return to the heart.
The nurse is teaching a client diagnosed with heart failure about preload. Which principle would be most appropriate to provide to the client? A-Preload represents the volume work of the heart. B-Preload is the pressure or tension work of the heart. C-Preload is the ability of the heart to change its force of contraction. D-Preload determines the frequency by which the ventricles contract and blood is ejected.
Preload represents the volume work of the heart. >>Preload is the distending force that stretches the heart muscle just prior to work of the onset of ventricular contraction. It represents the volume of blood stretching the ventricular muscle fibers at end of diastole (i.e., end-diastolic volume) and is the sum of the blood remaining in the heart at the end of systole (end-systolic volume) and the venous return to the heart. The pressure or tension work of the heart refers to afterload. The ability of the heart to change its force of contraction refers to cardiac contractility. The frequency by which the ventricles contract and blood is ejected refers to heart rate.
A nurse is teaching a client the correct technique for taking an arterial pulse. The nurse explains that the pulsations are: A-Pressure pulses B-Korotkoff sounds C-Blood flow in the veins D-Turbulence of the blood flow
Pressure pulses >>The arterial pressure pulse represents the energy that is transmitted from molecule to molecule along the length of the vessel. When taking a pulse, it is the pressure pulses that are felt. Pressure pulses have no direct relation to the blood flow. It is the pressure pulses that produce the Korotkoff sounds heard during blood pressure measurement. Pressure pulses would be felt even if there was no blood flow at all.
Colloidal osmotic pressure acts differently than the osmotic effects of the plasma proteins. What is its action? A-Pulls fluid back into the capillary B-Pushes fluid into the extracellular spaces C-Controls the direction of the fluid flow in the large arteries D-Pulls fluid into the interstitial spaces
Pulls fluid back into the capillary >>The osmotic pressure caused by the plasma proteins in the blood tends to pull fluid from the interstitial spaces back into the capillary. This pressure is termed colloidal osmotic pressure so as to differentiate the osmotic effects of the plasma proteins, which are suspended colloids, from the osmotic effects of substances such as sodium and glucose, which are dissolved crystalloids.
The heart consists of four valves. Which are the semilunar valves? Select all that apply. A- Tricuspid B- Mitral C- Pulmonary D- Aortic
Pulmonary Aortic RATIONALE: The heart's semilunar valves are the pulmonary and aortic values. The heart's atrioventricular valves are the tricuspid and the mitral.
The heart is a four-chambered pump. What is the function of the right ventricle? A- Receives blood returning to the heart from the systemic circulation B- Receives oxygenated blood from the lungs C- Pumps blood to the lungs D- Pumps blood into the systemic circulation
Pumps blood to the lungs RATIONALE: The right ventricle pumps blood to the lungs. The right atrium receives blood returning to the heart from the system circulation. The left atrium receives oxygenated blood from the lungs. The left ventricle pumps blood into the systemic circulation.
Which blood vessel layer is made primarily of muscle? A)Tunica media B) Tunica intima C) Tunica externa D) Tunica adventitia
Tunica media
The nurse is reviewing the anatomy and physiology of the heart. What is the function of the right atrium? A-Receives blood returning to the heart from the systemic circulation B-Receives oxygenated blood from the lungs C-Pumps blood into the systemic circulation D-Pumps blood to the lungs
Receives blood returning to the heart from the systemic circulation RAITOANLE: The right atrium receives blood returning to the heart from the system circulation. The left atrium receives oxygenated blood from the lungs. The right ventricle pumps blood to the lungs. The left ventricle pumps blood into the systemic circulation.
The electrical activity of the heart is recorded on the ECG. What does the T wave on the ECG represent? A-Depolarization of the sinoatrial node B-Depolarization of the ventricular conduction system C-Repolarization of the atrium D-Repolarization of the ventricles
Repolarization of the ventricles >>The P wave represents the depolarization of the sinoatrial node. The QRS complex represents the depolarization of the ventricles. The T wave represents repolarization of the ventricles, not the atrium
A client has had an acute myocardial infarction (MI). The brother of the client has a history of angina. The client asks how he will know if his brother's pain is angina or if the brother is actually having an MI. Which statement is correct? A) Chest pain with angina only occurs during the day; MI pain is more likely at night. B) Chest pain with angina only occurs at rest; MI pain occurs during a stressful time. C) Pain is more severe and lasts longer with angina than with an MI. D) Rest and intake of nitroglycerin relieve chest pain with angina; they do not relieve chest pain with an MI.
Rest and intake of nitroglycerin relieve chest pain with angina; they do not relieve chest pain with an MI.
A client has prominent jugular veins. What type of medical problem is associated with prominent jugular veins? A-Left-sided heart failure B-Right-sided heart failure C-Shock D-Cerebrovascular accident (stroke)
Right-sided heart failure RAITONALE: Right-sided heart failure is seen with prominent jugular veins.
If the parasympathetic neurotransmitter releases acetylcholine, the nurse should anticipate observing what changes in the ECG pattern? A-Heart rate 150 beats/minute, labeled as supraventricular tachycardia B-Disorganized ventricular fibrillation C-Complete cardiac standstill D-Slowing of heart rate to below 60 beats/minute
Slowing of heart rate to below 60 beats/minute >>Acetylcholine, the parasympathetic neurotransmitter released during vagal stimulation of the heart, slows down the heart rate by decreasing the slope of phase 4. The catecholamines, the sympathetic nervous system neurotransmitters epinephrine and norepinephrine, increase the heart rate by increasing the slope or rate of phase 4 depolarization. Fibrillation is the result of disorganized current flow within the ventricle (ventricular fibrillation). Fibrillation interrupts the normal contraction of the atria or ventricles. In ventricular fibrillation, the ventricles quiver but do not contract. Thus, there is no cardiac output, and there are no palpable or audible pulses (i.e., cardiac standstill).
The difference between the end-diastolic and end-systolic volumes is called what? A-Stroke volume B-Cardiac output C-Ejection fraction D-Cardiac reserve
Stroke volume RAITONALE: Stroke volume is determined by the difference between end-diastolic and end-systolic volumes. Cardiac output is determined by stroke volume and heart rate. Ejection fraction is the volume ejected from the left ventricle. Cardiac reserve is determined by cardiac output.
A nurse is evaluating a client to determine the effectiveness of medications given to reduce left ventricular afterload. Which hemodynamic parameter is most appropriate for the nurse to monitor? A-Mean arterial pressure (MAP) B-Systemic vascular resistance (SVR) C-Blood pressure D-Pulmonary artery wedge pressure (PAWP)
Systemic vascular resistance (SVR) >>Afterload is resistance to ejection of blood from the heart. Resistance is the opposition to flow caused by friction between the moving blood and the stationary vessel wall. In the peripheral circulation, the collective resistance of all the vessels in that part of the circulation is referred to as the peripheral vascular resistance (PVR), also known as the systemic vascular resistance.
A client says that when the hospital checked his blood pressure after he lost a lot of blood in a work-related accident, the top number (systolic pressure) was lower than usual but the bottom number (diastolic pressure) was about the same. Why is this? A-Systemic vasoconstriction maintained the diastolic pressure. B-The stroke volume increased with blood loss. C-The heart rate increased with blood loss. D-Systemic vasodilation maintained the diastolic pressure.
Systemic vasoconstriction maintained the diastolic pressure. >>Systemic vasoconstriction, not vasodilation, would maintain the diastolic pressure. The stroke volume and heart would not affect the diastolic pressure with blood loss.
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? A-The client has decreased fluid volume. B-The client has an increased cardiac output. C-The client has stenosis of the jugular veins. D-The client has increased pressure related to right-sided heart failure.
The client has increased pressure related to right-sided heart failure. >>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.
What does the nurse teach is the principal factor that determines how long the client can exercise? A) The client's age B) The client's mental status C) The client's medical history D) The client's heart and lung capacity
The client's heart and lung capacity RATIONALE: The principal factor that determines how long and effectively a person will be able to exercise is the capacity of the heart, lungs, and circulation to deliver oxygen to the working muscles. Cardiac performance is influenced by the work demands of the heart and the ability of the coronary circulation to meet its metabolic needs.
Downstream peripheral pulses have a higher pulse pressure because the pressure wave travels faster than the blood itself. What occurs in peripheral arterial disease? A-The pulse decreases, rather than increases, in amplitude. B-The reflected wave is transmitted more rapidly through the aorta. C-Downstream peripheral pulses are increased even more than normal. D-Downstream peripheral pulses are greater than upstream pulses.
The pulse decreases, rather than increases, in amplitude. >>With peripheral arterial disease, there is a delay in the transmission of the reflected wave so that the pulse decreases, rather than increases, in amplitude.
Local control of blood flow is regulated by mechanisms that match blood flow to the metabolic needs of the tissue. Which components of the vascular system are involved in the short-term control of blood flow? Select all that apply. A- Tissue B- Smooth muscle C- Endothelial cells D- Collateral circulation
Tissue Smooth muscle Endothelial cells RATIONALE: Over the short term, the tissues autoregulate through the synthesis of vasodilators and vasoconstrictors derived from the tissue, smooth muscle, or endothelial cells; over the long term, blood flow is regulated by creation of collateral circulation.
The heart consists of four valves. Which are the heart's atrioventricular valves? Select all that apply. A- Tricuspid B- Mitral C- Pulmonary D- Aortic
Tricuspid Mitral RAITONALE: The heart's atrioventricular valves are the tricuspid and the mitral. The semilunar valves are the pulmonary and aortic.
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? A-Troponin C and troponin T B-Troponin A and troponin I C-Troponin T and troponin I D-Troponin A and troponin C
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 nurse identifies the blood vessel layer that constricts to regulate and control diameter as: A-Tunica media B-Tunica adventitia C-Tunica externa D-Tunica intima
Tunica media RATIONALE: The tunica media, the middle layer, is largely a smooth muscle layer that constricts to regulate and control the diameter of the vessel. The tunica externa, also known as the tunica adventitia, refers to the outermost layer of a vessel. The tunica intima refers to the innermost layer that prevents platelet adherence and blood clotting.
Preload, the stretch on the heart before contraction, is largely determined by which factor? A-Venous blood return B-Vascular resistance C-Force of contraction D-Ventricular emptying
Venous blood return RAIONTALE: Preload represents the amount of blood the heart must pump with each beat and represents the volume of blood stretching the ventricular muscle fibers at the end of diastole. Pressure (resistance), contraction, and ventricular emptying relate to afterload.
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? A-Blood ejected from each ventricle with each contraction B-Blood pumped by each ventricle in 1 minute C-Venous return to the heart D-Resistance to ventricular emptying
Venous return to the heart >>Preload is the amount of venous return to the heart. Afterload is the pressure in which the muscle exerts its contractile force in order to move blood into the aorta. Contractility is the ability of the heart to change its force of contraction without changing its resting length.
The cardiac cycle describes the pumping action of the heart. Which statement is correct about systole? A-Ventricles contract and blood is ejected from the heart. B-Atria contract and blood is ejected from the heart. C-Ventricles relax and blood fills the heart. D-Atria relax and blood fills the heart.
Ventricles contract and blood is ejected from the heart. RAITONALE: Systole occurs when the ventricles contract and blood is ejected from the heart. Diastole occurs when the ventricles are relaxed and blood fills the heart.
In the circulatory system, pressure is inversely related to which factor? A-Velocity B-Volume C-Tension D-Viscosity
Volume >> In the circulatory system, pressure is inversely related to volume. Arterial circulation contains a lower percentage of total blood volume and has higher pressure than the venous circulation, which contains the majority of circulating blood. Flow is related to viscosity and radius is related to wall tension. Velocity is inversely proportional to the cross-sectional area of the vessel.
A nurse is assessing a client who lost consciousness during a wrestling match when his opponent applied a neck hold. The client likely lost consciousness because: A-cardiac output suddenly dropped. B-a baroreceptor was stimulated. C-the position caused bradycardia. D-the client experienced temporary cardiac ischemia.
a baroreceptor was stimulated. >>The baroreceptors of the carotid body monitor blood pressure. The hold likely increased the pressure on the baroreceptor and mimicked an increase in BP, with a resultant extreme decrease in BP and unconsciousness. Neck pressure would be unlikely to cause ischemia, bradycardia, or a reduction in CO.
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: A-the high oxygenation needs of cardiac muscle and the role of coronary circulation. B-the relationship between venous return and stroke volume. C-the molecular structure of actin and myosin and their effect on contraction. D-the physiologic function of chemoreceptors and baroreceptors.
the relationship between venous return and stroke volume. >>The Frank-Starling principle addresses the relationship between venous return and stroke volume. It does not directly address the characteristics of actin and myosin. The principle is unrelated to coronary circulation, chemoreceptors and baroreceptors.
The nurse is reviewing the circulatory system. Which statements are correct about the functional organization of the circulatory system? Select all that apply. A-The heart exchanges gases, nutrients, and wastes. B-The arterial system distributes oxygenated blood to the tissues. C-The venous system collects deoxygenated blood from the tissues. D-The capillaries pump blood.
The arterial system distributes oxygenated blood to the tissues. The venous system collects deoxygenated blood from the tissues. RATIONALE: The circulatory system consists of the heart, which pumps blood; the arterial system, which distributes oxygenated blood to the tissues; the venous system, which collects deoxygenated blood from the tissues and returns it to the heart; and the capillaries, where exchange of gases, nutrients, and waste takes place.
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? A-Small diameter of this vessel will cause it to rupture more readily. B-The larger the aneurysm, the less tension placed on the vessel. C-As the aneurysm grows, more tension is placed on the vessel wall, which increases the risk for rupture. D-The primary cause for rupture relates to increase in abdominal pressure, such as straining to have a bowel movement.
As the aneurysm grows, more tension is placed on the vessel wall, which increases the risk for rupture. >>Because the pressure is equal throughout, the tension in the part of the balloon with the smaller radius is less than the tension in the section with the larger radius. The same holds true for an arterial aneurysm in which the tension and risk of rupture increase as the aneurysm grows in size. Wall tension is inversely related to wall thickness, such that the thicker the vessel wall, the lower the tension, and vice versa. Although arteries have a thicker muscular wall than veins, their distensibility allows them to store some of the blood that is ejected from the heart during systole, providing for continuous flow through the capillaries as the heart relaxes during diastole.
Which enzyme has a powerful vasodilator effect on arterioles and increases capillary permeability? A- Histamine B- Serotonin C- Prostaglandins D- Arachidonic acid
Histamine RATIONALE: 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. Serotonin causes vasoconstriction and plays a major role in control of bleeding. Prostaglandins (synthesized from constituents of the cell membrane like long-chain fatty acid, arachidonic acid) produce either vasoconstriction or vasodilation.
A nursing instructor is explaining arterial circulation to a group of nursing students. What is the most appropriate information for the nurse to provide concerning arterial pressure gradient in the arterial side of systemic circulation? A-It contains one-sixth of the total blood volume. B-The vascular pressure is lower than the venous circulation. C-It contains approximately two-thirds of the total blood volume. D-Arteries are more distensible than veins.
It contains one-sixth of the total blood volume. >>The arterial side of the circulation contains approximately one-sixth of the blood volume. Arterial circulation exerts much greater pressure than the pressure on the venous side of the circulation. The venous side contains approximately two-thirds of the blood. Because of their thicker, muscular walls arteries are less distensible than veins.
Which of the following is true regarding pulmonary circulation? A) The system functions with an increased arterial pressure to circulate through the distal parts of the body. B) It is a low-pressure system that allows for improved gas exchange. C) It is the larger of the two circulatory systems. D) It consists of the left side of the heart, the aorta, and its branches.
It is a low-pressure system that allows for improved gas exchange.
Which of the following is true regarding pulmonary circulation? A-The system functions with an increased arterial pressure to circulate through the distal parts of the body. B-It is a low-pressure system that allows for improved gas exchange. C-It is the larger of the two circulatory systems. D-It consists of the left side of the heart, the aorta, and its branches.
It is a low-pressure system that allows for improved gas exchange. >>The pulmonary circulation consists of the right heart and the pulmonary artery, capillaries, and veins. It is the smaller of the systems and functions at a lower pressure to assist with gas exchange.
The physician states that a client has adequate collateral circulation. The nurse interprets this as: A-Long-term compensatory regulation of blood flow B-Anastomosis of the arterial and venous circulation C-Establishment of compensatory lymphatic drainage D-Development of increased collagen
Long-term compensatory regulation of blood flow >>Collateral circulation is a mechanism for the long-term regulation of local blood flow. In the heart and other vital structures, anastomotic channels exist between some of the smaller arteries. These channels permit perfusion of an area by more than one artery. When one artery becomes occluded, these anastomotic channels increase in size, allowing blood from a patent artery to perfuse the area supplied by the occluded vessel. Lymph node removal requires establishment of compensatory lymphatic drainage. The aging process produces the development of increased collagen.
The heart and blood vessels receive both sympathetic and parasympathetic innervation from neural control. What controls the parasympathetic-mediated slowing of the heart rate? A-The vasomotor center B-The cardioinhibitory center C-The medullary center D-The innervation center
The cardioinhibitory center >>The medullary cardiovascular neurons are grouped into three distinct pools that lead to sympathetic innervation of the heart and blood vessels and parasympathetic innervation of the heart. The first two, which control sympathetic-mediated acceleration of heart rate and blood vessel tone, are called the vasomotor center. The third, which controls parasympathetic-mediated slowing of heart rate, is called the cardioinhibitory center.
The circulatory system is a closed system that is divided into two parts. Which statement is correct about the closed system? A-The low pressure pulmonary circulation links circulation and gas exchange in the lungs. B-The low pressure systemic circulation system provides oxygen and nutrients to the tissues. C-The high pressure systemic circulation system links circulation and gas exchange in the lungs D-The high pressure pulmonary circulation provides oxygen and nutrients to the tissues.
The low pressure pulmonary circulation links circulation and gas exchange in the lungs. >>The low pressure pulmonary circulation links circulation and gas exchange in the lungs, and the high pressure systemic circulation provides oxygen and nutrients to the tissues.
Which sequence is the correct pathway for blood flow through the heart? A- right atrium - tricuspid valve - right ventricle - pulmonary artery - lungs - pulmonary vein - left atrium - mitral valve - left ventricle - aorta B- left atrium - tricuspid valve - left ventricle - pulmonary artery - lungs - pulmonary vein - right atrium - mitral valve - right ventricle - aorta C- left atrium - bicuspid valve - left ventricle - pulmonary artery - lungs - pulmonary vein - right atrium - tricuspid valve - right ventricle - aorta D- right atrium - bicuspid valve - right ventricle - pulmonary artery - lungs - pulmonary vein - left atrium - tricuspid valve - left ventricle - aorta
right atrium - tricuspid valve - right ventricle - pulmonary artery - lungs - pulmonary vein - left atrium - mitral valve - left ventricle - aorta RAITONALE: The correct pathway for blood flow through the heart is the right atrium - tricuspid valve - right ventricle - pulmonary artery - lungs - pulmonary vein - left atrium - mitral valve - left ventricle - aorta.
