Regulation of MAP

Question 1

explain what happens when you stand up to MAP?

Answer 1

due to the decreased venous return and the lowered CO…the baroreceptors pick it up and fire less so the SNS kicks up and increases the BP back to normal

Question 2

explain the role of vasopressin in the blood?

Answer 2

it is released when baroreceptor senses low pressures and leads to water retention as well as increasing BP of vessels

Question 3

what is another name for vasopressin

Answer 3

antidiuretic hormone

Question 4

what is bulk flow in capillaries?

Answer 4

when water flows following its gradient

Question 5

what is the main driver that pushes fluid out in the capillaries?

Answer 5

hydrostatic pressure

Question 6

what is the main driver that pulls fluid into the capillaries?

Answer 6

colloid osmotic pressure (oncotic)

AKA plasma oncotic pressure

Question 7

define the plasma oncotic pressure

Answer 7

component of osmotic pressure contributed by macormolecules like plasma proteins…mainly albumin

Question 8

if a patient has liver failure and has low albumin…what often happens in capillaries and why?

Answer 8

you get more filtration because of the low protein content and low plasma oncotic pressure

Question 9

define capillary hydrostatic pressure

Answer 9

this is the pressure of the fluid within the capillary and is the biggest factor in capillary exchange

Question 10

is capillary hydrostatic pressure higher at venular or arteriolar end of a cpaillary?

Answer 10

arteriolar

Question 11

what does capillary hydrostatic pressure drive?

Answer 11

ultrafiltration

Question 12

as you move across the capillary what happens with filtration?

Answer 12

it eventually loses the gradient and you start to get reabsorption

Question 13

is an increase in sympathetic nervous system increasing filtration of absorption? explain

Answer 13

increases absorption because it causes more constriction in arteriole sphincters and therefore a decrease in the capillary hydrostatic pressure

Question 14

what happens to filtration when the venous pressure really increases?

Answer 14

it will increase the filtration in the capillary because venous system does not have sphincter and the pressure increases in the capillaries

Question 15

name three changes that lead to edema

Answer 15

increased venous pressure
arteriolodilation
hypoproteinemia

Question 16

name two changes that lead to increase in absorption

Answer 16

dehydration

arteriolar constriction

Question 17

how does shock happen?

Answer 17

a severe insult to MAP regulation systems

Question 18

describe the changes of pulmonary capillary wedge pressure, CO, and SVR in hypovolemic shock?

Answer 18

decreased capillary wedge pressure
decreased CO
increased SVR

Question 19

describe the changes of pulmonary capillary wedge pressure, CO, and SVR in cardiogenic shock?

Answer 19

increased pulmonary capillary wedge pressure
decreased CO
increased SVR

Question 20

describe the changes of pulmonary capillary wedge pressure, CO, and SVR in distributive shock?

Answer 20

normal or decreased pulmonary capillary wedge pressure
increased CO
decreased SVR

Question 21

name the two possible causes of hypovolemic shock

Answer 21

acute blood loss and profound dehydration

Question 22

what is the primary insult that leads to hypovolemic shock

Answer 22

decrease in preload causes decrease in stroke volume

Question 23

what are the compensatory mechanisms in hypovolemic shock?

Answer 23

tachycardia and increased SVR

Question 24

what is treatment for hypovolemic shock?

Answer 24

either fluids or blood transfusion…depends on the cause

Question 25

what is the cause of cardiogenic shock? what is the insult that leads to cardiogenic shock?

Answer 25

very low CO

usually due to poor contractility

Question 26

name three compensatory mechanisms in cardiogenic shock

Answer 26

increased preload, tachycardia, increased SVR

Question 27

name three drug treatments for cardiogenic shock

Answer 27

increase contractility with inotrope…dobutamine
decrease fluid with diuretic
reduce afterload with ACE inhibitor

Question 28

what is the common cause of distributive shock?

Answer 28

sepsis

Question 29

what is the primary insult that helps distributive shock?

Answer 29

vasodilation…decreased SVR

Question 30

why is cardiac output high in distributive shock?

Answer 30

tachycardia coupled with low SVR and low afterload of heart

Question 31

what is the compensatory mechanism in distributive shock?

Answer 31

tachycardia

Question 32

name two treatments for distributive shock

Answer 32

vasopressors

fluid resuscitation

Question 33

when giving a drug to increase the SVR in distributive shock…what receptor must it be an agonist of?

Answer 33

A1 receptors to lead to vasoconstriction…like phenylephrine