Blood pressure Flashcards
What is systolic pressure?
pressure in system when heart contracts- area of high pressure
What is diastolic pressure?
pressure when heart relaxed- blood vessel pressure drops
What do you measure blood pressure in?
mmHg - millimetres of mercury
What is blood pressure described as
Pressure of blood in major blood vessels of heart
How do you measure blood pressure in dogs?
Take a chorotid artery
Put a canula ( tube) in it
When the heart contracts it will push blood against the column of mercury- makes the column of mercury go up
When the heart relaxes- the column of mercury goes down
Read off column of mercury high and low pressure point
What do you use to measure humans blood pressure
Sphygmomanometer
How do you measure blood pressure in humans?
- Wrap a cuff around arm which is attached to the bulb
that can inflate the cuff , putting pressure on the brachial artery. - apply enough pressure to collapse that artery - means you are above the systolic pressure
- Slowly release pressure from cuff, until that point where some blood starts to flow = applying a little less pressure= systolic pressure
- The more air you let out the bag, more blood flows through, until you are not constricting blood flow or collapsing artery= diastolic pressure
- Determing the pressure when blood vessel first starts opening which is systolic pressure, and the pressure when the blood vessel is not collapsed at all= diastolic pressure.
What is brachial artery
a superficial blood vessel in the upper arm
What happens when normal blood flow in vessel
No noise = flowing smoothly = can hear turbulant blood flow
What are the sounds of Korotkoff?
When sounds dies away.(diastolic)
No turbulant blood flow = not restricting vessels at all =
What does a stethoscope do when you measure blood pressure?
put just below the cuff on breakel artery,
normal blood flow of muscle makes no noise- as it flows smoothly
Decrease pressure in cuff, some blood is starting to flow through, you will hear a soft tapping= systolic pressure
Decrease pressure even more, more and more blood starts to flow, makes a continuous rushing sound, then the sound dies when there is no turbulent blood flow and no constricting vessel which means you are at the Diastolic pressure.put just below the cuff on breakel artery, normal blood flow of muscle makes no noise- as it flows smoothly
Decrease pressure in cuff, some blood is starting to flow through, you will hear a soft tapping= systolic pressure
Decrease pressure even more, more and more blood starts to flow, makes a continuous rushing sound, then the sound dies.
How do you determine blood flowing?
Using a stethoscope- from its sounds that it makes
How do you write the blood pressure?
systolic/diastolic
What is the average blood pressure?
120/80
Why does the measured blood pressure vary throughout the circulatory system
As its highest and its greatest variation is in the major arteries near the heart such as the arota larfe and small arteries and arterioles
However then by the time the blood returns to the heart via the vena cava, the pressure is almost 0(drops) and variation gets less due to being so far from the pump and heart and the elastic nature of veins and blood vessels which will even out the blood flow.
What happens to blood pressure throughout the circulatory system
Varies
When is bp highest and variation is greatest
In major arteries nearest heart
Less in capillaries and veins
When is pressure almost 0
by the time the blood returns to the heart via the vena cava
What happens by the time the blood returns to heart via vena cava
variation gets less due to being so far from the pump and heart and the elastic nature of veins and blood vessels which will even out the blood flow
What happens if you cut artery
A lot of blood spurt out
What happens if you cut vein
Hardly any blood spurts out
How does blood pressure vary?
- From person to person (inter-individual)
- With age ( increases with age )
- Depend on what you are doing or feeling (intra-individual )
What to make sure when taking bp
- Px relaxed
- Take it same time every day as it varies according to time of day
What happens if you take b.p and its not 120/80, should you refer straight away
No, dont refer to health service, need to investigate - factors, repeats
What is white coat syndrome
People scared coming to see doctors which increases bp = variable
What is the bp formula?
bp = cardiac output x peripheral resistance