Perfusion Flashcards
CAD results in impaired blood flow to ________
a. veins
b. brain
c. myocardium
d. toes
c. myocardium
what is the formula used to determine Blood pressure
cardiac output x systemic vascular resistance = blood pressure
define cardiac output
the amount of blood pumped by the heart in 1 minute
define blood pressure
force exerted by the blood against the walls of the blood vessels
how do you determine cardiac output?
heart rate (HR) x stoke volume (SV)
define stroke volume
the volume of blood ejected everytime the heart beats (ml per beat)
define systemic vascular resistance (SVR)
force opposing the movement of blood in the vessels
what determines SVR?
Determined by the radius of arteries and arterioles
* Arteries narrow= SVR
* Arteries dilate=SVR
Regulation of BP is a complex process involving both _________ and _______mechanisms.
short term and long term
short term mechanisms include: SELECT ALL THAT APPLY
a. sympathetic nervous system
b. vascular endothelium
c. renal processes
d. hormonal processes
A and B
the long-term mechanisms include: SELECT ALL THAT APPLY
a. sympathetic nervous system
b. renal processes
c. vascular endothelium
d. hormonal processes
b and d
the renal and hormonal processes regulate ____ resistance and ______
a. venous; blood volume
b. arteriolar; blood volume
c. arteriolar; blood vescocity
d. venous; blood thickness
b
how does angiotensin II act on the heart and blood vessels?
Causes vasoconstriction and tissue growth –> remodeling of vessel walls=primary HTN and atherosclerosis
how do changes in blood volume affect blood pressure?
the higher the blood volume, the greater work is needed for the heart to pump blood through the circulatory system
increased blood volume = increased blood pressure
how does overall compliance affect blood pressure?
the elastic characteristics of the vessels contribute to the overall pressure in the vessels. The more elastic the blood vessels are, the lower the blood pressure.
increased blood vessel elasticity = decreased blood pressure
how does cardiac output affect blood pressure?
related to heart rate and stroke volume
increased HR + Stroke Volume = increased cardiac output = increased BP
how does peripheral resistance affect blood pressure?
the resistance of the arteries is related to the overall compliance characteristics
increased peripheral resistance = decreased overall compliance = increased arterial blood pressure
Normal blood pressure range
systolic: less than 120
and
diastolic: less than 80
elevated blood pressure range
systolic: 120-129
and
diastolic: less than 80
high blood pressure (hypertension) stage 1 range
systolic: 130-139
or
diastolic: 80-89
high blood pressure (hypertension) stage 2 range
systolic: 140 or higher
or
diastolic: 90 or higher
hypertensive crisis (consult doctor immediately)
systolic: higher than 180
and/or
diastolic: higher than 120
define primary hypertension (essential or idiopathic)
elevated BP without an identified cause
define secondary hypertension
elevated BP with a specific cause that often can be identified and corrected. can cause cardiovascular complications if left untreated
what are some common causes of secondary hypertension?
- Cirrhosis
- Coarctation or congenital narrowing of the aorta
- Drug-related: estrogen replacement therapy, oral contraceptives, corticosteroids, nonsteroidal anti-inflammatory drugs (e.g., cyclooxygenase-2 inhibitors), SNS stimulants (e.g., cocaine, monoamine oxidase)
- Endocrine disorders (e.g., pheochromocytoma, Cushing syndrome, thyroid disease)
- Neurologic disorders (e.g., brain tumors, quadriplegia, traumatic brain injury)
- Pregnancy-induced hypertension
- Renal disease (e.g., renal artery stenosis, glomerulonephritis)
- Sleep apnea
What are some risk factors for primary hypertension?
- age
- Alcohol
- Diabetes
- elevated serum lipids
- ethnicity
- excess dietary sodium
- family history
- Gender
- Obesity
- sedentary lifestyle
- socioeconomic status
- stress tobacco use
patients are frequently asymptomatic until the target organ disease occurs
True or False
True
what are some signs and symptoms of hypertension?
- Fatigue, Reduced activity
tolerance - Dizziness
- Palpitations, angina
- Dyspnea
- Vision changes
- Nocturia
What are some complications of hypertension?
- coronary artery disease
- left ventricle hypertrophy
- heart failure
- retinopathy
- peripheral vascular disease
- renal disease
- stroke cognition
list the diagnostics for hypertension
- history and physical exam
- ophthalmic
- labs
- urinalysis (UA)
- fasting glucose
- BMP, CBC, and lipid profile
- Ca + and Mg+
- tests
- 12 ECG
- echocardiogram
hypertension treatments
- lifestyle changes
- pharmacological
- nursing/collaborative
- focus on individual, modifiable risk factors that contribute to HTN
- develop a realistic health maintenance plan for the patient and their family
- promote treatment adherence
which of the following medications are used to treat hypertension? SELECT ALL THAT APPLY
a. Diuretics
b. Adrenergic-inhibiting agents
c. Direct vasodilators
d. Angiotensin inhibitors
e. Calcium channel blockers
all of the above
how does hydrochlorothiazide work?
inhibits NaCl reabsorption in distal convoluted tubule
how does furosemide work to treat hypertension?
inhibits NaCl reabsorption in the loop of Henle
how does spironolactone work to treat hypertension?
inhibits Na+ retaining and K+ excreting effect of aldosterone in the distal and collecting tubules
*CHECK POTASSIUM LEVELS. DON’T WANT PATIENT TO BECOME HYPERKALEMIC
How does clonidine work to regulate BP?
reduces sympathetic outflow from CNS = peripheral vasodilation, decrease SVR
how does Doxazosin work to regulate BP?
blocks alpha-adrenergic effects = peripheral vasodilation, decreased SVR
how does metoprolol work to regulate BP?
block beta 1 adrenergic receptors; reduce sympathetic vasoconstrictor tone, decrease renin secretion by kidneys
how does propranolol work to reduce BP?
blocks beta 1 and bet 2 adrenergic receptors
how does carvedilol work to regulate BP?
peripheral vasodilation and HR reduction
how do hydralazines regulate BP?
direct arterial vasodilation, reduces SVR
how does nitroglycerin regulate BP?
reduces pre load and SVR
- low dose: venous dilation
*high dose: arterial dilation
how does sodium nitroprusside regulate BP?
direct arterial vasodilation, reduces SVR
how do ACE inhibitors (-pril) regulate BP?
reduce conversion of angiotensin 1 to angiotensin II (prevents vasoconstriction)
how do ARBs (-sartan) regulate BP?
prevents action of angiotensin II and produces vasodilation and increased NA+ and water excretion
how does diltiazem regulate BP?
inhibits movement of calcium across cell membrane = vasodilation
how does amlodipine regulate BP?
relaxes vascular smooth muscle = decreases SVR and arterial BP
what are some causes of hypertensive emergencies?
preeclampsia, eclampsia, stimulant drugs, head injury
what are some symptoms of hypertensive emergencies
-Hypertensive encephalopathy
* Cerebral edema
- Renal insufficiency
* Acute Kidney Injury→ renal failure
- Cardiac decompensation
* Unstable angina, MI, pulmonary edema
hypertensive emergency treatments
- Hospitalization
- Hemodynamic monitoring
- Arterial line: direct measure
of arterial pressures
- Arterial line: direct measure
- IV Anti-hypertensive
medications- Direct vasodilators or
adrenergic inhibitors - Treat MAP (mean arterial
pressure) - Slowly decrease pressure to
stabilize
- Direct vasodilators or
