Week 9 Flashcards
Perfusion; HTN & MI
Perfusion
passage of oxygenated capillary blood through body tissues
Laminar blood flow is
parallel
what is the greatest risk factor for formation of atherosclerosis
endothelial injury
Natriuresis, ANP, and BNP act at the nephron to retain water T or F
False, naturesis is a diuretic; gets rid of water
If a pts BP is 128/78 what category does it fall into
Elevated HTN
T or F; baroreceptor regulation of blood pressure is designed to correct short-term imbalances w/ position change
True, this is the reason you don’t pass out when you go from laying to standing
What are the main vessels in the body
Arteries
T OR F, The greater the pressure in the arteries and arterioles, the higher resistance against the the heart pump
TRUE:
- high BP= pressure backs up into the heart and resistance/ workload increase
What are the three distinct layers of the arterial wall
- tunica adventita
- tunica media
- tunica intima
What is the Endothelium
A smooth, contiguous surface of endothelial cells that make up the outermost layer of all arteries and the heart
what are a few of the metabolic functions
- fluid filtration
- maintenance of blood vessel tone
- hemostasis
- angiogenesis; make new vessel
- neutrophil chemotaxis; vehicle for WBC
- hormone secretion
Larger the diameter of the vessel, higher the pressure T or F
FALSE
- larger diameter= pressure lower
- small diameter= pressure higher
Turbulent flow is
- flow is interrupted which creates areas of stagnant blood and exposes the endothelial lining to blood constitutes
- creates whooshing sound
- flow is circular instead of parallel
The difference between systolic and diastolic pressure (ideally around 40mm Hg)
Pulse pressure
The amount of blood ejected from the heart per contraction
Stroke volume
Period of cardiac contraction
systolic
Period of cardiac relaxation
diastolic
Arterial wall tension
the force in the vessel wall that opposed the distending pressure inside the vessel
Why is a Troponin level necessary in addition the ECG to diagnosis an MI?
-Troponin level is needed with ECG to confirm MI diagnosis. Troponin levels can distinguish new damage where ECG will show new and old damage which may be mistaken for each other
Why would it be important to give the patient with ACS or MI oxygen?
-To reduce the workload of the lungs which will in turn reduce workload for the heart as well. The supplemental oxygen helps with this and it ensures both the lungs and heart are getting adequate oxygenation.
Why do they say patients should chew an aspirin tablet at the onset of chest pain?
-Aspirin can help reduce platelets from sticking onto eachother. Aspirin is also considered an antiplatelet which stops the platelets from sticking to eachother
Why is nitroglycerin given to patients experiencing chest pain or a possible heart attack?
-Nitroglycerin is a vasodilator which makes the vessels bigger so pressure is reduced and blockage/ obstruction can also be cleared out.
Why is Morphine often given to patients experiencing an acute MI?
-Morphine helps with the pain of an MI and it also helps take away the chest pressure/ elephant sitting on chest feeling
Why can’t thrombolytic agents be given to every MI patient if they help dissolve blood clots?
-A patient could already be on a blood thinner and more blood thinning medication can cause patient to bleed internally.
Why is a patient likely to suffer a cardiac dysrhythmia after experiencing an MI?
-The heart electrical current goes all wonky and become interrupted due to the heart having to overcompensate for a blockage or low blood supply with high demand. Along with the dead tissue is no longer able to conduct energy to go throughout the heart and body.
Why is the extent of damage caused by an MI influenced by the location of the occlusion, the length of time occluded and the heart’s availability of collateral circulation?
Location: Vessel below the area can be blocked off and ischemic injury occurs due to lack of oxygen resulting in tissue death
Time: More time wasted means more heart tissue damage
Collateral circulation: Does the blood have another pathway to go to or is it going to be blocked
Blood pressure regulation systems
- baroreceptors
- RAAS
- Antidiuretic hormone(ADH)
- natriuresis; natural diuretic
LDL
low density lipoprotein
- BAD Cholesterol
HDL
- high density lipoprotein
- GOOD cholesterol
what are the 3 layers of the heart wall
- epicardium(outer)
- myocardium(middle)
- endocardium(very thin inner)
- pericardium(fibrous membrane sac)
What are collateral branches
- extra branches that were stimulated by exercise
- additional paths of circulation
- regenerating branches
cardiac conduction system
- SA Nodes
- AV Nodes
- Left Bundle of His
- Right Bundle of His
- Purkinje fibers
What happens if blood pressure drops and the cardiac output is constant
- peripheral vascular resistance increases(vasoconstriction occurs)
- trys and maintains cardiac output
The nurse states that although atherosclerosis has many causes, the process is initiated with what event
Endothelial damage
- precursor; needs damage first before WBC/ foam cells come in play
What is true for both hyperlipidemia and hypertension
They may present with few signs and symptoms, yet causes significant damage
what are drug eluting stents
Platelets don’t stick to stent and they slide on through
