Lecture 15: Cardiac Failure, Heart Sounds, and Circulatory Shock

Question 1

What is cardiac failure?

Answer 1

failure of the heart to pump enough blood to satisfy the needs of the body

Question 2

How does the ANS compensate for acute cardiac failure?

Answer 2

baroreceptor reflex
chemoreceptor reflex
CNS ischemic response

Question 3

In acute cardiac failure, if all the ventricular musculature is diffusely damaged but still functional, ________ strengthens this damaged musculature

Answer 3

sympathetic strengthens

Question 4

If part of the musculature is nonfunctional and part is still normal, the normal muscle is ______

Answer 4

strongly stimulated

Question 5

Strong sympathetic stimulation increases tone of most of the blood vessels in circulation and therefore increase ______

Answer 5

venous return

Question 6

What are the acute effects of a heart attack?

Answer 6

reduced cardiac output

damming of blood in the veins—increased venous pressure

Question 7

In an acute heart attack, what does the compensation?

Answer 7

sympathetic nervous system

Question 8

What are the chronic compensations after an acute heart attack?

Answer 8

• results for partial heart recovery and rental mention of fluid
• max pump ability is depressed to less than one half normal
• any heavy exercise causes immediate return to symptoms of acute failure
• increase in right atrial pressure can maintain cardiac output near normal level

Question 9

In left heart failure, blood pumps into the lungs but ______

Answer 9

not adequately out of them

Question 10

If blood cannot be pumped out of the lungs, what happens?

Answer 10

mean pulmonary filing pressure rises because of shift of large volumes of blood from the systemic circulation into the pulmonary circulation
pulmonary capillary pressure increases

Question 11

What are the two major problems with left heart failure?

Answer 11

pulmonary vascular congestion

pulmonary edema

Question 12

In severe acute left heart failure, pulmonary edema may happen so rapidly that it can cause death by ______ in _____ minutes

Answer 12

suffocation, 20-30

Question 13

What does an arteriovenous fistula do?

Answer 13

overloads heart because of excessive venous return

venous return curve rotates upward

Question 14

What is beriberi?

Answer 14

thymine deficiency that leads to weakening of the heart
decreased blood flow to kidney — fluid retention
increased mean filling pressure
venous curve shifts to right

Question 15

_______ results in major decrease in peripheral vascular resistance

Answer 15

AV fistula

Question 16

What is the first heart sound?

Answer 16

AV valves close on at the onset of ventricular systole

Question 17

What is the second heart sound?

Answer 17

semilunar values close at end of systole

Question 18

What is a left to right congenital defect?

Answer 18

blood flows backward and fails to flow through systemic circulation

Question 19

What is right to left congenital defect?

Answer 19

blood flows from right to left side of heart, bypassing lungs

Question 20

What type of defect is ductus arteriosus?

Answer 20

left to right

Question 21

What type of defect is tetralogy of fallot?

Answer 21

right to left

Question 22

What is the definition of circulatory schock?

Answer 22

generalized inadequate blood flow through the body, to the extent that the body tissues are damaged, especially because of too little oxygen and other nutrients delivered to the tissue cells

Question 23

What are some cardiac abnormalities that decrease the ability of the heart to pump blood?

Answer 23

myocardial infarction
toxic state of the heart
severe valve dysfunction
heart arrhythmias 
circulatory shock

Question 24

What are factors the decrease venous return?

Answer 24

diminished blood volume
decreased vascular tone
obstruction of blood flow

Question 25

What are powerful sympathetic reflexes initiated by?

Answer 25

arterial baroreceptors and other vascular stretch receptors

Question 26

What does powerful sympathetic reflexes result from?

Answer 26

decrease in arterial pressure after hemorrhage

decreases in pressures in the pulmonary arteries and veins in the thorax

Question 27

What effects result from powerful sympathetic reflexes

Answer 27

arterioles constriction in most parts of the systemic circulation
veins and venous reservoirs constrict
heart activity increases markedly

Question 28

Compensatory mechanisms that return blood volume back to normal after shock

Answer 28

absorption of large quantities of fluid from intestinal tract
absorption of fluids into blood capillaries from the interstitial spaces of the body
conservation of water and salt by kidneys
increased this and appetite fro salt

Question 29

What is non progressive shock?

Answer 29

sympathetic reflexes and other factors compensate enough to prevent further deterioration of the circulation
negative feedback mechanisms

Question 30

What is progressive shock?

Answer 30

positive feedbacks

when arterial pressure falls low enough, coronary blood flow decreases below requirement for nutrition of the myocardium

Question 31

What is one of the important features of progressive shock?

Answer 31

whether or not it is hemorrhagic in origin

Question 32

What are the factors in final lethal progression of schock?

Answer 32

vasomotor failure
blockage of small vessels 
increased vascular permeability 
release of toxins by necrotic tissue
cardiac depression caused by endotoxin
generalized cellular deterioation

Question 33

What is neurogenic shock?

Answer 33

shock occurring from any loss of blood volume

Question 34

What are the causes of neurogenic shock?

Answer 34

deep general anesthesia
spinal anesthesia
brain damage