NU238 Test 2
While intubated for surgery, a client has inadvertently had his vagus nerve stimulated. What effect would the surgical team expect to observe?
decreased heart rate as a result of parasympathetic innervation of the heart
The nurse is reviewing the circulatory system. Which statements are correct about the functional organization of the circulatory system?
The arterial system distributes oxygenated blood to the tissues. The venous system collects deoxygenated blood from the tissues.
Sypathetic Nervous System
arouses + expends energy, accelerates heart beat, raises blood pressure, cool with sweat, to make you alert and ready for action (fight/flight)
what is the function of the pulmonic valve?
controls the direction of blood flow from the right side of the heart to the lungs
how many gallons of blood are pumped per day?
1800
What is the normal left ventricular ejection when determined by angiocardiography?
55-75%
A client with high blood pressure has swollen ankles. Which physiologic factor could relieve this condition?
A decrease in the hydrostatic pressure that drives fluid into the tissue
Which statement describes phase 4 of the action potential of cells in the sinoatrial (SA) node?
A slow depolarization occurs when Na+ is transported out of the cell and K+ moves back in, resulting in resting membrane potential.
Wolff-Parkinson-White (WPW) syndrome
A syndrome in which an extra electrical pathway in the heart causes a rapid heartbeat.
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
after a myocardial infraction why so much muscle was damaged if only the left circumflex vessel was blocked.
Heart attack; Death of cardiac muscle due to ischemia.
A 72-year-old female has been told by her physician that she has a new heart murmur that requires her to go visit a cardiologist. Upon examination, the cardiologist informs the client that she has aortic stenosis. After the cardiologist has left the room, the client asks, "What caused this [aortic stenosis] to happen now?" The clinic nurse responds:
Heart murmurs result from tumultuous flow through a diseased heart valve that is too narrow and stiff. This flow causes a vibration called a murmur."
What do baroreceptors do?
Increase sympathetic stimulation of the heart and blood vessels
what is adequate collateral circulation?
Long-term compensatory regulation of blood flow
A physician has ordered the measurement of a cardiac client's electrolyte levels as part of the client's morning blood work. Which statement best captures the importance of potassium in the normal electrical function of the client's heart?
Potassium is central to establishing and maintaining the resting membrane potential of cardiac muscle cells.
A nurse is taking a manual measure of a client's blood pressure. The nurse knows that which factors related to blood flow underlies the ability to hear blood pressure by auscultation (listening)?
Pressure pulsation that exceeds the velocity of blood flow is audible and coincides with systolic BP.
what is the function of the right atrium?
Receives blood returning to the heart from the systemic circulation
The client asks how he will know if his brother's pain is angina or if the brother is actually having an MI
Rest and intake of nitroglycerin relieve chest pain with angina; they do not relieve chest pain with an MI.
A pathologist is examining histological (tissue) samples from a client with an autoimmune disease. Which characteristic of muscle samples would signal the pathologist that the samples are cardiac rather than skeletal muscle?
The muscle cells are arranged as an interconnecting lattice-work.
Analysis has shown that a client's right atrial pressure is 30 mm Hg. What is the most likely conclusion that the client's care team will draw from this piece of data?
The pressure is excessive given that the right atrium should be at atmospheric pressure.
there are three main atrial pressure waves that occur during the cardiac cycle. What are the three main atrial pressure waves?
a,c,v
Cardiac dysrhythmias
abnormal rhythms
supernormal excitatory period on the first complex on the rhythm strip
after the jump
systemic circulation
circulation that supplies blood to all the body except to the lungs
abnormalities of cardiac rate and rhythm;
conductivity
When explaining to a client why there was only minimal muscle damage following 99% occlusion of the left anterior descending artery, the nurse will explain that this is primarily due to
development of collateral circulation that build channels between some of the smaller arteries, usually when the flow is decreased gradually.
What is the function of the capillaries in the circulatory system?
exchange gases, nutrients, and wastes
myocardial infarction
heart attack
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
Which enzyme has a powerful vasodilator effect on arterioles and increases capillary permeability?
histamine
pericarditis
inflammation of the pericardium
what is true about pulmonary circulation?
it is a low pressured system that allows for gas exchange
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?
junctions of the subclavian and internal jugular veins
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
atrioventricular valves
mitral and tricuspid
A nurse notes that the PR interval on a client's electrocardiogram tracing is 0.22 seconds. Which action should the nurse take?
monitor the client and document the findings
ECG monitoring has been found to be more sensitive than a client's report of symptoms when identifying transient ongoing myocardial ischemia. Why is this?
most ECG-detected ischemic events are clinically set
aortic stenosis
narrowing of the aorta
Nitroglycerin is the drug of choice in treating angina. What does nitroglycerin release into the vascular smooth muscle of the target tissues?
nitric oxide
What are the semilunar valves?
pulmonary and aortic
what is the function of the right ventricle
pumps blood to the lungs
atrial fibrillation
rapid, random, ineffective contractions of the atrium
atrial fibrillation
rapid, random, ineffective contractions of the atrium The contraction of the ventricles and the atria can range from 400-600 beats per minute
What does the T wave on ECG represent?
repolarization of ventricles
what type of medical problem is associated with prominent jugular veins?
right sided heart failure
Glomerula capillaries have
small openings that allow for large amounts of smaller molecular substances to filter through the glomeruli
A 20-year-old college student, with no past medical history, arrives at the emergency room complaining of severe palpitations and dizziness that started this morning following a night of studying. The student is very upset that this is happening because the final exams are the following day. The cardiac monitor shows a heart rate of 110, regular rhythm with occasional premature ventricular complexes. T
sympathetic nervous system
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 due to right sided heart failure
Frank-Starling Mechanism
the mechanism by which an increased amount of blood in the ventricle causes a stronger ventricular contraction to increase the amount of blood ejected
What occurs in peripheral arterial disease?
the pulse decreases in amplitude
ventricular fibrillation
the rapid, irregular, and useless contractions of the ventricles
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
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
systole
ventricles contract and blood is ejected from the heart
What is preload?
volume of blood in ventricles at end of diastole
vasodilation
widening of blood vessels
what is the pacemaker of the heart called?
SA node
Correct sequence for the generation of electrical impulses in the heart causing ventricular contraction?
SA node - AV node - bundle of His - bundle branches - Purkinje fibers
A 71-year-old man is slated for pacemaker insertion for treatment of a third-degree AV block. The man's nurse has been educating him around his diagnosis and treatment and answering the numerous questions he has about his health problem. Which teaching point should the nurse include in this client teaching?
The root problem is that the top chambers of your heart and the bottom chambers of your heart aren't coordinating to pump blood efficiently.
signs of tachycardia
decreasing cardiac output due to less ventricular filling time.
Which chamber of the heart pumps blood into the systemic circulation?
left ventricle
afterload
resistance to left ventricular ejection