Mean Arterial Pressure: Lecture 9 Flashcards
(45 cards)
What determines mean arterial pressure?
rearrange cardiac output equation
MAP = cardiac output x total peripheral resistance
Why is the MAP so important? What is it’s purpose?
- Contributes to Hearts workload
- Provides driving forces to move blood
- The number 1 regulated thing in our body
- otherwise impaired nutrients and oxygen
What does hypotension refer to?
low blood pressure
What is our systolic bp and diastolic bp for hypotension?
90/60 mm Hg
What are the 4 main symptoms of hypotension?
- Dizziness
- Fainting
- Blurred vision
- Fatigue
What causes these symptoms of hypotension
- insufficient blood flow to the brain, muscles
- insufficient oxygen distribution
What are the causes of hypotension?
- dehydration
- pregnancy
- heart failure
- anemia
What are the risk factors for hypotension?
- age
- medication
- certain diseases
Why would Parkinson’s disease lead to low blood pressure?
it affects the autonomic nervous system, aka PNS and SNS to regulate blood pressure
Is Hypotension or Hypertension known as the silent killer?
Hypertension
What does hypertension refer to?
High blood pressure
What are the ranges of systolic and diastolic bp in stage 1 of hypertension?
130-139/80-89 mm Hg
What are the ranges of systolic and diastolic bp in stage 2 of hypertension?
> =140/>=90
What are the ranges of systolic and diastolic bp in stage 3 (Hypertensive crisis) of hypertension?
> 180/>120 EMERGENCY
What are the severe symptoms of hypertension?
- stroke
- heart attack (myocardial ischemia)
- kidney failure
- blindness
- dementia
- sexual dysfunction
What are the causes of hypertension?
- atherosclerosis
- kidney disease
- sleep apnea
- thyroid issues
What are the risk factors for hypertension?
(most are modifiable)
- age
- genetics
- obesity
- inactivity
- smoking
- high sodium intake
- stress
- alcohol consumption
Conduit vessels refer to what?
Arteries
What is the function of an artery?
takes blood from the heart and distributes it to the various organs/tissues
How do we have blood flow move efficiently?
- Minimize the resistance
- via larger diameter
- low contractility, smooth muscle
- high compliance, elasticity - Artery walls need to be STRONG
In a rested state how much blood do we have in the aorta during systole? and how long does it last?
75 ml, 0.3 seconds
Is the stretch of the aorta when blood comes into it passive or active?
passive
During systole, the aorta and heart will do what?
aorta = expands passively
heart = contracting and emptying
During diastole, the aorta and heart will do what?
aorta = recoil passively
heart = relaxing and filling
*aortic valve is shut meaning blood has to move forward