Pressure and Flow in Arteries and Veins Flashcards Preview

Cardiovascular > Pressure and Flow in Arteries and Veins > Flashcards

Flashcards in Pressure and Flow in Arteries and Veins Deck (30)
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1
Q

How is arterial blood pressure measured?

A

Auscultation of korotkoff sounds using a sphygmomanometer and a stethoscope

2
Q

When the pressure in the sphygmomanometer cuff is higher than systolic pressure what sound is heard on a stethoscope?

A

Silence

3
Q

When the pressure in the sphygmomanometer cuff is just lower than systolic pressure what sound is heard on a stethoscope?

A

Tapping

4
Q

When the pressure in the sphygmomanometer cuff is significantly lower than systolic pressure what sound is heard on a stethoscope?

A

Thumping

5
Q

When the pressure in the sphygmomanometer cuff is slightly higher than diastolic pressure what sound is heard on a stethoscope?

A

Muffled sounds

6
Q

When the pressure in the sphygmomanometer cuff is less than diastolic pressure what sound is heard on a stethoscope?

A

Silence

7
Q

What should be heard normally when a stethoscope is on the arm?

A

Silence

8
Q

Where should a stethoscope be placed on the arm to auscultate for Korotkoff sounds?

A

Over the brachial artery, in the antecubital fossa

9
Q

What effect so elastic arteries have on blood pressure?

A

They act as a pressure reservoir and dampen down pressure variations

10
Q

What is arterial pressure affected by?

A

Stroke volume
Velocity of ejection
Elasticity of arteries
Total peripheral resistance

11
Q

What is normal arterial pressure?

A

120/80 mmHg

12
Q

How does normal arterial pressure change?

A

It increases with age

13
Q

How does pressure change through blood vessels?

A

Pressure falls throughout the vascular tree from arteries to arterioles to capillaries and finally the veins

14
Q

What is the difference in blood pressure between the pulmonary and systemic circulation?

A

The pulmonary circulation has a pressure about 1/5th that of the systemic circulation

15
Q

How does velocity change in blood vessels?

A

Velocity is related to total cross section so is highest in the aorta and vena cava and lowest in the capillaries

16
Q

Which vessels have the highest total cross-sectional area?

A

Capillaries

17
Q

How is flow affected in veins?

A

Veins are distensible and collapsible so external influences affect flow

18
Q

What affect can gravity have on blood flow?

A

Doesn’t affect driving pressure from arteries to veins
Causes venous distension in legs
Causes venous collapse in the neck

19
Q

What is venous distension?

A

Stretching of the veins because there is a greater volume of blood moving through them than there should be

20
Q

What is jugular venous pressure?

A

The blood pressure in the veins at the neck and can be used to estimate the central venous pressure

21
Q

What is jugular venous collapse?

A

When the veins in the neck close

22
Q

What does jugular venous collapse show?

A

The height of the collapse can be used to estimate central venous output

23
Q

How is blood brought back up to the heart in the venous system?

A

Skeletal muscle pump
Respiratory pump
Venomotor tone
Systemic filling pressure

24
Q

What is venomotor tone?

A

Contraction of smooth muscle surrounding the venues and veins

25
Q

What is systemic filling pressure?

A

The pressure created by ventricles that is then transmitted through the vascular tree to the veins

26
Q

What is the skeletal muscle pump?

A

The contraction of skeletal muscle that forces blood to move through veins

27
Q

What is the respiratory pump?

A

The pressure gradient between the infra and supra diaphragmatic parts of the inferior vena cava caused by inspiration that pulls blood towards the heart

28
Q

What is deep vein thrombosis?

A

The formation of blood clots within a deep vein

29
Q

What are varicose veins?

A

When the valves in veins no longer work so blood builds up in areas and stretches the veins and twists then

30
Q

What can happen if the skeletal muscle pump doesn’t work properly?

A

Deep vein thrombosis

Varicose veins