19.7 Blood Presssure

Question 1

Highest in aorta
Pressure results when flow is opposed by resistance
Pumping action of heart generates blood flow
High –> Low pressure (decreases as vessel gets smaller)

Answer 1

Systemic blood pressure

Question 2

Determined by two factors:
1. Elasticity of arteries near heart
2. Volume of blood forced into them at any time

Answer 2

Arterial blood pressure

Question 3

Blood pressure near heart
Rises and falls with each heartbeat
“Stretches then relaxes”

Answer 3

Pulsatile

Question 4

Pressure exerted in aorta during ventricular contraction
Left ventricle pumps into aorta, stretching it
First sound when when taking pressure (around 120 mmHg)

Answer 4

Systolic pressure

Question 5

Lowest level of aortic pressure when heart is at rest
Sound disappearing when taking pressure (around 70-80 mmHg)

Answer 5

Diastolic pressure

Question 6

Difference between systolic and diastolic pressure
Pulse pressure phases out near ends of arterioles
Can be felt as a pulse

Answer 6

Pulse pressure

Question 7

Caused by rhythmic expansion and contraction of arteries due to heart contraction
What we hear when taking blood pressure

Answer 7

Pulse

Question 8

Pulse and blood pressure, respiratory rate and body temperature

Answer 8

Vital signs

Question 9

Most routine spot to measure pulse

Answer 9

Radial pulse

Question 10

Areas where arteries are close to body surface
Can be compressed to stop blood flow in event of hemorrhaging

Answer 10

Pressure points

Question 11

pressure point list

Question 12

Blood pressure gauge

Answer 12

Sphygmomanometer

Question 13

Average pressure in a patient’s arteries during one cardiac cycle
Pressure that propels blood to tissues
Between 70-100 mmHg

Answer 13

Mean arterial pressure

Question 14

True or false. The heart spends more time in diastole

Answer 14

True

Question 15

Lower pressure desirable to avoid rupture
Ranges from 35 (start) to 17 mmHg (end)

Answer 15

Capillary pressure

Question 16

Changes very little during cardiac cycle
Small pressure gradient, only about 15 mmHg

Answer 16

Venous pressure

Question 17

Contraction of skeletal muscle “milking” blood back toward heart
Valves prevent backflow
________ pump

Answer 17

Muscular pump

Question 18

Pressure changes during breathing move blood towareds heart by squeezing abdominal veins as thoracic veins expand
__________ pump

Answer 18

Respiratory pump

Question 19

Under sympathetic control, smooth muscles constrict, pushing blood back towards heart

Answer 19

Sympathetic venoconstriction

Question 20

What are the three factors regulating blood pressure?

Answer 20

1. Cardiac output
2. Peripheral resistance
3. Blood volume

Question 21

Neural controls
Hormonal controls
Renal controls

Answer 21

3 things that affect major factors

Question 22

Condition where blood vessels inadequately fill and cannot circulate blood normally
“Shocking” to the body

Answer 22

Circulatory shock

Question 23

Results from large scale blood loss

Answer 23

Hypovolemic shock

Question 24

Results from extreme vasodilation and decreased peripheral resistance
Not enough oxygen for lungs

Answer 24

Vascular shock

Question 25

Results when an inefficient heart cannot sustain adequate circulation

Answer 25

Cardiogenic shock

Question 26

Sustained elevated arterial pressure of 140/90 or higher "Silent killer" Doesn't show signs for 10-20 years

Answer 26

Hypertension

Question 27

Heart works harder Accelerates atherosclerosis Makes tunica media thicker Myocardium thickens and weakens

Answer 27

Prolonged hypertension

Question 28

No underlying cause identified 90% of hypertension cases

Answer 28

Primary hypertension

Question 29

Less common form of hypertension Due to identifiable disorders such as: Kidney disease Obstructed real arteries Endocrine disorders

Answer 29

Secondary hypertension

Question 30

Low blood pressure (90/60) Not a concern unless it causes inadequate blood flow

Answer 30

Hypotension

Question 31

Blood flow through body tissues; Involved in oxygen delivery, gas exchange, absorption of nutrients, urine formation

Answer 31

Tissue perfusion

Question 32

Sympathetic nervous system and hormones control blood flow through whole body

Answer 32

Extrinsic control

Question 33

Autoregulation; Local conditions that regulate blood flow to that area Local arterioles feed capillaries can undergo modification of their diameters

Answer 33

Intrinsic control

Question 34

Fastest in aorta, slowest in capillaries, then increases in veins (Allows for exchange between blood and tissues)

Answer 34

Velocity of blood flow

Question 35

Where fluid is forced out of in capillary

Answer 35

Arterial end

Question 36

Where blood is returned in capillary

Answer 36

Venous end

Question 37

Force exerted by fluid pressing against wall (boundary) Due to blood pressure

Answer 37

Hydrostatic pressure (HP)

Question 38

Capillary blood pressure that tends to force fluids through capillary walls Greater in arterial end

Answer 38

Capillary hydrostatic pressure (HPc)

Question 39

Abnormal increase in amount of interstitial fluid Aka swelling

Answer 39

Edema

Question 40

Excess interstitial fluid in subcutaneous tissues Swollen feet images

Answer 40

Pitting edema

Question 41

Pressure pushing fluid back into vessel Usually assumed to be 0

Answer 41

Interstitial fluid hydrostatic pressure (HPif)

Question 42

Force opposing hydrostatic pressure Created by large non diffusible molecules that are unable to cross capillary wall Encourage osmosis

Answer 42

Colloid osmotic pressure (OP)

Question 43

Created by non diffusible plasma proteins pulling water back into capillary About 26 mmHg AKA - oncotic pressure

Answer 43

Capillary colloid osmotic pressure (OPc)

Question 44

Comprises all forces acting on capillary bed

Answer 44

Net filtration pressure (NFP)

Question 45

Net fluid flow out arterial end Positive NFP

Answer 45

Filtration

Question 46

Net fluid flow in at venous end Negative NFP

Answer 46

Reabsorption

Question 47

True or false. Plasma is half total blood volume?

Answer 47

True

Question 48

Due to non diffusible solutes that cannot cross the boundary

Answer 48

Osmotic pressure

Question 49

(Hpc + OPif) - (HPif + OPc)

Answer 49

Net reabsorption