CVS 2

Question 1

Stress volume

Answer 1

The blood contained in arteries

Question 2

Site of highest resistance in CVS

Answer 2

Arterioles

Question 3

Have the largest ‘total’ cross-sectional and surface area

Answer 3

Capillaries

Question 4

Formed from merged capillaries

Answer 4

Venules

Question 5

Unstressed volume

Answer 5

The blood contained in veins

Question 6

Contains the highest proportion of blood in CVS (? %) (reservoir function)

Answer 6

Veins; 65%

Question 7

Percentage of blood that is cells

Answer 7

Hematocrit

Question 8

Velocity is directly proportional to _______ and inversely proportional to _______

Answer 8

Blood flow; cross-sectional area

Question 9

Turbulence is increased by ______ blood viscosity & ______ blood velocity

Answer 9

Decreased; increased

Question 10

Describes the distensibility of the blood vessels

Answer 10

Capacitance (compliance)

Question 11

Capacitance is _______ related to elastance or stiffness

Answer 11

Inversely

Question 12

Poiseuille’s Law

Answer 12

R = (8 x viscosity x length) / (radius to the 4th x pie)

Question 13

-10mmHg venous pressure poses high risk of?

Answer 13

VAE in Sagittal sinus

Question 14

Atrial contraction.

Enlarged in pulmonary HTN

Answer 14

A wave

Question 15

RV contraction (tricuspid valve bulging into atrium)

Answer 15

‘C’ wave

Question 16

Increased atrial pressure d/t filling against closed tricuspid valve. Enlarged in tricuspid regurgitation.

Answer 16

‘V’ wave

Question 17

Atrial relaxation + RV contraction (pulls atrium downward)

Answer 17

‘X’ descent

Question 18

Emptying of right atrium after tricuspid valve opens

Answer 18

‘Y’ descent

Question 19

Large wave not corresponding to a, v, or c wave. D/t complete heart block or junctional arrhythmias

Answer 19

Cannon wave

Question 20

Important in transport of nutrients to tissues.
Site of wast product removal.
Blood flow through capillaries is regulated by contraction & relaxation of arterioles and precapillary sphincters

Answer 20

The microcirculation

Question 21

Solute and water move across capillary wall via ________

Answer 21

Intercellular cleft (space b/w cells)

Question 22

Most important means by which substances are transferred b/w plasma and interstitial fluid is by _______

Answer 22

Simple diffusion

Question 23

Capillaries in the liver and intestines where the clefts are exceptionally wide and allow passage of protein

Answer 23

Sinusoids

Question 24

2 major types of solid structures in interstitium are ______ & _______

Answer 24

Collagen fibers & proteoglycan filaments

Question 25

Produced by endothelial cells & causes relaxation of vascular smooth muscles by cGMP such as nitric oxide

Answer 25

Endothelium-derived relaxing factor (EDRF)

Question 26

ACh causes vasodilation by stimulating the production of _____ in vascular smooth muscles. Autoregulation

Answer 26

NO

Question 27

Order for autoregulation

Answer 27

NO-dependent vasodilators on receptors > Ca > Nitric oxide synthase > L-arginine > NO > gaunylyl cyclase > GTP > cGMP > relaxation

Question 28

What enzyme converts L-arg to NO?

Answer 28

Nitric oxide synthase

Question 29

What is precursor of NO?

Answer 29

L-arg

Question 30

How does NO act/ cause relaxation?

Answer 30

cGMP

Question 31

Ability of a tissue to maintain blood flow relatively constant over a wide range of arterial pressures

Answer 31

Autoregulation

Question 32

Factors determining autoregulation in Heart

Answer 32

Local metabolites, decreased O2, adenosine, NO

Question 33

Factors determining autoregulation in Brain

Answer 33

Local metabolites, changes in CO2 (pH)

Question 34

Factors determining autoregulation in kidneys

Answer 34

Myotonic and tubuloglomerular feedback

Question 35

factors determining autoregulation in lungs

Answer 35

Hypoxia causes vasoconstriction

Question 36

Factors determining autoregulation of skeletal muscle

Answer 36

Local metabolites, lactate, adenosine, K

Question 37

An increase in blood flow to an organ that occurs after a period of occlusion of flow

Answer 37

Reactive hyperemia

Question 38

BF to an organ is proportional to its metabolic activity (more blood flow to exercising muscles)

Answer 38

Active hyperemia

Question 39

Vascular smooth muscle contracts when it is stretch is explained by ________ hypothesis

Answer 39

Myogenic

Question 40

Tissue supply of O2 is matched to tissue demand for O2

Answer 40

Metabolic hypothesis

Question 41

Degradation of ATP produces _________, a vasodilator substance that acts directly on vascular smooth muscle to increase intracellular cAMP and induce vasodilation

Answer 41

Adenosine

Question 42

Histamine causes _______ dilation and _______ constriction > increased capillary hydrostatic pressure and increased filtration out of the capillaries, resulting in local edema

Answer 42

Arteriolar; venous

Question 43

Causes arteriolar constriction; help to prevent blood loss. Implicated in the vascular spasm of migraine headache

Answer 43

Serotonin (5HT)

Question 44

Prostacyclin is a _______ and thromboxane A2 is a ________

Answer 44

Vasodilator; vasoconstrictor

Question 45

Where is the vasomotor center (VMC) located?

Answer 45

Bilaterally in reticular substance of medulla & lower third of pons

Question 46

Hering’s nerve

Answer 46

Carotid sinus nerve

Question 47

Responsible for the minute-to-minute regulation of arterial BP

Answer 47

Baroreceptor reflex

Question 48

Steps in baroreceptor reflex

Answer 48

1. Decrease in arterial pressure decreases stretch on the walls of the carotid sinus; 2. Decrease stretch decreases firing rate of carotid sinus nerve (hering’s nerve/ CN IX) which stimulates VMC in brain; 3. The VMC decreases parasympathetic (vagal) outflow to heart and increases sympathetic outflow

Question 49

Valsalva maneuver MOA

Answer 49

Increases intrathoracic pressure which decreases venous return/CO/Pa > increase in HR. Afterwards, rebound increase in venous return/ CO/ Pa > decrease in HR

Question 50

Where is angiotensin I converted to angiotensin II?

Answer 50

Lungs

Question 51

4 effects of Angiotensin II:

Answer 51

1. Stimulates secretion of aldosterone by adrenal cortex (increases Na reabsorption); 2. Increases Na-H exchange > contraction alkalosis; 3. Increases thirst; 4. Causes vasoconstriction of the arterioles

Question 52

How does cerebral ischemia regulate arterial pressure?

Answer 52

When brain is ischemic the conc. of CO2 & H in brain tissue increase > chemoreceptor in VMC increases sympathetic flow > vasoconstriction

Question 53

______ receptors respond to decrease in BP & cause release of ADH form _______

Answer 53

Atrial; posterior pituitary

Question 54

2 effects of ADH:

Answer 54

V1 receptor- potent vasoconstrictor that increases TPR; | V2 receptor- increases water reabsorption by renal distal tubules & collecting ducts

Question 55

ANP & BNP inhibit what?

Answer 55

Renin (causing increased excretion of Na & water and causes relaxation of vascular smooth muscle via cGMP)

Question 56

Increase in atrial pressure increases HR. Stretch of atria sends signals to VMC via vagal afferents to increase HR & contractility. Prevents damming of blood in veins, atria, & pulm.

Answer 56

Bainbridge Reflex

Question 57

_____ supplies the SA and AV node

Answer 57

RCA

Question 58

CAD most common;y involves ______

Answer 58

LAD

Question 59

Increased BP increased PCWP

Answer 59

Increased afterload & O2 consumption > increase depth of anesthesia to dilate & nitro

Question 60

Ischemia with increased HR

Answer 60

Increased O2 consumption, decreased coronary BF. > beta blocker

Question 61

Ischemia with decreased BP & decreased or normal PCWP

Answer 61

Decrease depth of anesthesia, FLUIDS, Neo

Question 62

Ischemia with decreased BP increased PCWP

Answer 62

Heart is failing give inotropes (dopamine), NG (to decrease venous return), Neo (to increase BP and coronary perfusion)

Question 63

Ischemia with normal hemodynamics

Answer 63

NG & CCB