79. Physiology - Control of arterial blood pressure 1

Question 1

what is blood pressure

Answer 1

“the outwards (hydrostatic) pressure exerted by the blood on blood vessel walls”

Question 2

what is ‘systemic systolic arterial blood pressure’

Answer 2

the pressure exerted by the blood on the walls of the aorta and systemic arteries when the heart contracts

Question 3

systolic blood pressure should not reach/exceed what?

Answer 3

140 mm Hg

Question 4

what is Diastolic Arterial Blood Pressure

Answer 4

the pressure exerted by the blood on the walls of the aorta and systemic arteries when the heart relaxes

Question 5

diastolic blood pressure should not reach/exceed…?

Answer 5

90 mm Hg (under resting conditions)

Question 6

what is the term for very high blood pressure

Answer 6

hypertension

Question 7

define hypertension

Answer 7

Clinic blood pressure of 140/90 mmHg or higher and day time average of 135/85 mmHg or higher

Question 8

what is pulse pressure

Answer 8

the difference between systolic and diastolic blood pressure

Question 9

what is the pulse pressure is systolic BP is 120 and diastolic is 80

Answer 9

40 mm Hg

Question 10

what is the normal rage for pulse pressure

Answer 10

30 and 50

Question 11

can Laminar Flow in Normal Arteries be heard

Answer 11

no

Question 12

If external pressure (e.g. cuff pressure) exceeding the systolic blood pressure is applied to an artery. What happens? Can you hear anything

Answer 12

The flow in that artery would be blocked and no sound is heard through a stethoscope

Question 13

if the external pressure is kept between systolic and diastolic pressure the flow becomes…. and can you hear anything

Answer 13

turbulent. yes, you can hear.

Question 14

what equipment is used for blood pressure

Answer 14

sphygmomanometer and stethoscope

Question 15

when is diastolic pressure recorded

Answer 15

fifth Korotkoff sound (point when sound disappears)

Question 16

when do you record systolic BP

Answer 16

1st Korotkoff sound (first appearance of sound)

Question 17

a pressure gradient between ……and ….. …… drives blood around the systemic system

Answer 17

aorta and right atrium

Question 18

how would you calculate the pressure gradient

Answer 18

Mean Arterial Pressure (MAP) – Central Venous (right atrial) Pressure (CVP)

Question 19

what is mean arterial blood pressure (MAP)

Answer 19

the average arterial blood pressure during a single cardiac cycle, which involves contraction and relaxation of the heart

Question 20

how can MAP be estimated

Answer 20

MAP = (2x diastolic pressure) + systolic pressure
divided by 3

Question 21

so if systolic BP is 120 and diastolic BP is 80. what is MAP?

Answer 21

93.3 mmHg

Question 22

what is the normal range of MAP

Answer 22

70 -105 mmHg

Question 23

MAP of at least … mm Hg is needed to perfuse the coronary arteries, brain, and kidney

Answer 23

60

Question 24

what happens if MAP is to high

Answer 24

puts strain on vital organs

Question 25

what is cardiac output

Answer 25

The volume of blood pumped by each ventricle of the heart per minute

Question 26

what is stroke volume

Answer 26

Stroke Volume is the volume of blood pumped by each ventricle of the heart per heart beat

Question 27

what is systemic vascular resistance

Answer 27

The sum of resistance of all vasculature in the systemic circulation

Question 28

which vessels are the major resistance vessels

Answer 28

arterioles

Question 29

what is the short term regulation of mean arterial blood pressure

Answer 29

the baroreceptor reflex

Question 30

what kind of feedback does baroreceptor reflex use

Answer 30

negative

Question 31

where are the baroreceptors

Answer 31

Carotid Baroreceptor - carotid artery- via IXth CN
Aortic Baroreceptors - aorta-via Xth CN

Question 32

where do baroreceptors signal

Answer 32

send signals through the Vagus and glossopharyngeal nervs to the medulla

Question 33

The baroreceptor reflex helps maintain stable blood pressure, especially during sudden changes like when?

Answer 33

Postural changes aka standign up quickly

Question 34

when you stand up quickly, what happens to your venous return and MAP

Answer 34

• Gravity causes blood to pool in your legs which reduces venous return to the heart
• MAP briefly drops

Question 35

when you stand up quickly, your MAP drops. what happens next?

Answer 35

the drop in MAP reduces the firing rate of baroreceptors

Question 36

what are the autonomic adjustments when you stand up quickly and decrease MAP.

Answer 36

1. Decrease Vagal tone increasing HR and SV (Vagal tone refers to the activity of the vagus nerve, which is a key part of the parasympathetic nervous system)
2. Increased sympathetic tone - sympathetic tone increases causing
   Inc. SVR (arterioles constrict)
   Inc Venous return (veins constrict)

Question 37

failure of Baroreceptor responses to gravitational shifts in blood, when moving from horizontal to vertical position is called?

Answer 37

Postural Hypertension

Question 38

risk factors of postural hypertension are…?

Answer 38

Age, medication, certain diseases, prolonged bed rest, reduced intravascular volume

Question 39

Baroreceptors ONLY Respond to ‘…………’ Changes in Blood Pressure

Answer 39

Acute

Question 40

baroreceptor firing decreases if HBP is …..?

Answer 40

sustained

Question 41

Control of MAP in the longer-term is mainly by control of…?

Answer 41

Blood Volume