NUR 311 Ch 12 Review Questions and Correct Answers
8 views 0 purchase
Course
NUR 311
Institution
NUR 311
Point of Maximal impulse At the apex of the heart (apical HR) - Base is the top of the heart; apex is the bottom.
The coronary arteries Originate from the aorta just above the aortic valve - They supply arterial blood to the heart - Receive most of the blood from diastole, when the aortic valve cl...
NUR 311 Ch 12 Review Questions and
Correct Answers
Point of Maximal impulse ✅At the apex of the heart (apical HR)
- Base is the top of the heart; apex is the bottom.
The coronary arteries ✅Originate from the aorta just above the aortic valve
- They supply arterial blood to the heart
- Receive most of the blood from diastole, when the aortic valve closes.
Sinoatrial node (SA node) ✅the primary pacemaker of the heart
- initiates electrical impulses at an inherent rate of 60-100 beats per minute.
Depolarization ✅sodium ions move into the cell and potassium ions move out of the
cell
- leads to contraction of the myocardium
Repolarization ✅the exchange of ions reverts back to its polarized state
- rest period after contraction
Diastole ✅period in which the atria and ventricles are in a relaxed state, allowing the
ventricles to fill with blood
Systole ✅refers to the period of myocardial contraction
AV vavles ✅mitrial and tricuspid
Nursing Alert: Loss of atrial kick... ✅decreases CO, leading to the development of
symptoms in a patient such as:
- dizziness, lightheadedness, syncope, decreased activity tolerance, & hypotension.
- Atrial fibrillation is an arrhythmia that is known to be associated with the loss of this.
- Loss of coordinated contraction into the ventricle will decrease the left ventricular
preload and significantly lower CO.
Semilunar valves ✅aortic and pulmonic
Cardiac output ✅refers to the amount of blood pumped by each ventricle in L per min.
- adults = 4-6 L/min but varies greatly
- a function of the stroke volume and the heart rate
Stroke volume ✅is the amount of blood ejected with each heartbeat
- average is about 70 ml
, Ejection fraction ✅only a fraction of the blood present in the ventricles is ejected.
- EF on the left ventricle = 50-70% is commonly assessed because it is a noninvasive
measure of myocardial contractility
- the EF is lower in conditions that depress myocardial contractility (heart failure &
myocardial infarction)
Baroreceptors ✅located in the aortic arch and the right and left internal carotid arteries
- During HTN, these cells increase their rate of discharge transmitting impulses to the
medulla. This initiates PNS activity & inhibits SNS response; lowering the heart rate and
BP. (does just the opposite if responding to low BP)
Preload ✅refers to the pressure generated in the ventricles at the end of diastole and
the resultant stretching of the muscle fibers.
- is decreased by a reduction in the vol. Of blood returning to the ventricles.
- Vasodilation, diuresis, bleeding, vomiting, all reduce this.
- Therefore, it is increased with blood transfusion, IV continuous solutions, etc.
Afterload ✅The amount of resistance to ejection of blood from the ventricle, is the
second determinant of stroke volume.
Pulmonary vascular resistance ✅the right side of the heart collects venous blood,
which has a very low pressure and is met with little resistance as blood is ejected into
the pulmonary vascular system.
Systemic vascular resistance ✅the left side of the heart requires significantly higher
pressures to overcome resistance created by the arteries in the systemic circulation
.Nursing Alert: Preload reflects the... ✅volume of blood returning to the right and left
ventricles at the end of diastole.
- Central venous pressure monitoring measures right heart preload, whereas, PA
monitoring measures left ventricular preload.
Contractility ✅refers to the force generated by the contracting myocardium under any
given condition
- is enhanced by circulating catecholamines, SNS, and certain meds (digoxin, IV
dopamine)
- An increase in this results in an increase in SV.
- But this is depressed by hypoxemia, acidosis and certain meds (beta blockers)
Gender considerations: Heart ✅Heart of a woman is smaller
- coronary arteries of the female heart are smaller and thus occlude from
atherosclerosis more easily
- this makes procedures such as cardiac catheterization and percutaneous coronary
interventions more difficult
- resting HR, SV, and EF are generally higher than males
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller twishfrancis. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $8.99. You're not tied to anything after your purchase.
