CH 22 Cardiac Failure & CH 24 Circulatory Shock

Question 1

Cardiac Failure—the inability of the heart to pump enough blood to satisfy the ____ and nutrient needs of the heart.

• Referred to as a “________________” heart.
• Cardiac Failure can result from any heart condition that reduces contractility of the heart which results in diminished coronary blood flow—CAD, MI, etc.
• Other causes include damaged heart valves, high pressure (hypertension) or compression (cardiac tamponade), myocarditis, anemia, etc.

Answer 1

O2

hypoeffective

Question 2

Circulatory Dynamics in Cardiac Failure—1

I. Acute (immediate) Effects of Cardiac Failure:

If the heart becomes severely damaged and
the pumping ability is depressed, two main
effects occur:

1. ___________ in cardiac output

2.____________of blood in the veins which
increases venous pressure.

Answer 2

Reduction

Damming

Question 3

Circulatory Dynamics in Cardiac Failure—2

II. Compensatory Effects by Sympathetic Reflexes

1. Theses reflexes include baroreceptors, chemoreceptors, and ischemic response.
2. If part of the heart is damaged and nonfunctional, the functional area is strongly stimulated by __________ reflexes which actually makes the heart at least an
   effective pump
3. _____________reflexes also increases mean systemic filling pressure (due to venoconstriction) which sends more blood returning to the heart (VR). ↑VR → ↑ CO
4. ____________ reflexes become maximally developed within 30 seconds. Therefore, the person may only experience a few seconds of pain and fainting during a
   sudden, moderate heart attack.

Answer 3

sympathetic

Sympathetic

Sympathetic

Question 4

Circulatory Dynamics in Cardiac Failure—3..part 1

III. Chronic Stage of Cardiac Failure—Fluid Retention

• When CO decreases, this has a profound effect on renal (kidney) function.
• _____ output remains below normal as long as CO and MAP are significantly below normal.
• ______ output does NOT return to normal after a sudden, moderate heart attack until CO and MAP return to almost normal levels.

Answer 4

Urine

Urine

Question 5

Circulatory Dynamics in Cardiac Failure—3…part 2

III. Chronic Stage of Cardiac Failure—Fluid Retention

A. Benefits of Moderate FLUID RETENTION after Cardiac Failure:

1. Na + and water retention is caused by sympathetic constriction of renal _________arterioles which decreases GFR which decreases urinary output.
2. This sympathetic response also increases release of ____ (water retention), Angiotensin (water & Na+ retention), and Aldosterone (Na+ retention).
3. This increase in body fluid, and thus blood volume, helps increase _______

Answer 5

afferent

ADH

VR.

Question 6

Circulatory Dynamics in Cardiac Failure—3…part 3

III. Chronic Stage of Cardiac Failure—Fluid Retention

Acute cardiac failure rarely causes immediate peripheral edema because when the heart acutely fails as a pump, aortic pressure decreases and right atrial pressure increases. However, acute _____ heart failure can cause pulmonary edema that can cause death within minutes to hours.

Answer 6

left

Question 7

Circulatory Dynamics in Cardiac Failure—3…part 4

III. Chronic Stage of Cardiac Failure—Fluid Retention

B. Detrimental Effects of Fluid Retention in SEVERE Cardiac Failure:

• When the heart’s pumping ability is reduced even further, fluid retention has a detrimental effect because blood flow to the kidneys is ___________
• When the kidneys can no longer maintain some balance of fluid and salt intake with fluid and salt excretion, fluid retention becomes excessive.
• Excessive fluid retention has serious physiological consequences:
1. Increases the workload of an already damaged heart
2. ___________ the fibers of the heart causing further damage.
3. Filtration of fluid into the lungs causing pulmonary edema along with consequent deoxygenation of the blood.
4. Extensive edema in several other parts of the body—especially ________

Answer 7

reduced.

Overstretches

legs.

Question 8

Dynamics of Severe Cardiac Failure—Decompensated Heart Failure

1. In severe cardiac failure, the heart is so damaged that neither sympathetic reflexes nor fluid retention can return this excessively weakened heart to a normal____
2. Fluid continues to be retained and more and more ______ develops which leads to death.
3. This is referred to as _____________heart failure because the heart is not able to pump enough blood to the kidneys so they can filter and excrete the necessary
   amount of fluid.

Answer 8

CO.

edema

decompensated

Question 9

Decompensated heart failure can be tracked by the progressing edema, especially as it occurs in the lungs (hear a bubbling or crackling sound) and leads to_________(shortness of breath due to low O2 concentration).
***** The patient dies unless this chain of events can be reversed.

Answer 9

dyspnea

Question 10

Treatment for Decompensated Heart Failure

1. Strengthen the contractile force of the heart so it can pump an adequate volume of blood so that the kidneys can function normally. This is usually done by administering a ____________drug such as digitalis.
2. Balance fluid and Na+ intake with output. This is achieved by _________ water and Na+ intake and administering a diuretic drug, such as furosemide, to increase kidney excretion.

Answer 10

cardiotonic

reducing

Question 11

Cardiogenic (or Cardiac) Shock

This type of shock develops after an acute heart attack and there is progressive cardiac deterioration. With diminished blood flow, the heart itself suffers from lack of O2 and nutrients.

Vicious circle of Cardiogenic Shock:

1. Coronary blood supply is _______ and causes MAP to __________ which reduces coronary blood supply even more.
2. This makes the heart even weaker which decreases MAP even more—the circle has been established.

Answer 11

reduced

decrease

Question 12

Treatment for Cardiogenic Shock:

Once this shock sets in, the patient often dies before the compensatory reflexes can begin in order to return CO and MAP high enough to sustain life.

Steps for immediate treatment:
1. Immediate administration of digitalis to strengthen heart.
2. Infusion of whole blood, plasma, or a blood pressure-raising drug to increase MAP. If MAP can be elevated enough, coronary blood flow will increase enough to prevent the vicious circle from starting. This allows
time for other steps in treatment.
3. Surgically removing the blood clot in the artery along with a by-pass graft
OR
4. Catheterizing the blocked coronary artery and injecting streptokinase which is an enzyme that will dissolve the clot.
***Once a person goes into cardiogenic shock, survival rate is less than 30% even with appropriate medical treatment.

Answer 12

know the basics here.

Question 13

Cardiac Reserve —the maximum percentage that CO can increase above normal.
• A normal, healthy young adult has a cardiac reserve of ______ to ______%
• Highly trained athlete—500-600%
• A person with cardiac ischemia may have a small cardiac reserve
• A person in heart failure has ____ cardiac reserve

Answer 13

300-400%

NO

Question 14

3 Diagnosis of Low Cardiac Reserve with Exercise Test

1. Dyspnea (extreme shortness of breath) caused by the heart not pumping adequate amount of _________ blood to the heart and periphery.
2. ________ muscle fatigue—do not meet the O2 demand of exercising muscle
3. ________ HR because the sympathetic reflexes are trying to overcome the inadequate CO from low SV.

Answer 14

oxygenated

Extreme

Excessive

Question 15

Circulatory Shock—_________blood flow to all body tissues (including heart and circulatory vessels) so tissue damage occurs because of too little O2 and nutrients
delivered to the tissues.

• Similar to cardiogenic shock, once circulatory
shock begins it becomes progressively worse.

Shock Caused by Decreased CO

Answer 15

inadequate

Question 16

3 Stages of Circulatory Shock
Circulatory shock is divided into three stages based on severity (least to most):

1. ______________ Stage (sometimes called Compensated Stage)—the sympathetic reflexes eventually cause full recovery without outside intervention.
2. ___________ Stage—symptoms are still treatable but without relatively immediate medical attention, shock will steadily worsen until death.
3. ___________ Stage—even though the person may still be alive, the shock has progressed to the extent that even medical treatment cannot save the person’s life.

Answer 16

Nonprogressive

Progressive

Irreversible

Question 17

Hemorrhagic (Hyovolemic) Shock

1. Hypovolemia means diminished blood volume.
2. With hemorrhaging, blood volume decreases systemic filling pressure thus decreases ___ resulting in decreased ___.

Answer 17

VR

CO

Question 18

Compensatory Sympathetic Reflexes in Hemorrhagic Shock

• The decrease in AP, venous pressure, pressure in thorax, etc. all initiate ___________ reflexes so vasoconstriction occurs in blood vessels throughout
the system. This results in two important effects:

1. Vasoconstriction of arterioles to increase ____
2. Veins vasoconstrict to try to maintain ___ despite diminished blood volume

• Without these reflexive mechanisms, a blood loss of 15-20% within 30 minutes would result in death.
• With these mechanisms, blood loss can drop 30-40% in that time frame before life can no longer be sustained.
• The MAIN FOCUS of the sympathetic reflexes is to maintain AP rather than CO and it does this primarily through increasing TPR

Answer 18

sympathetic

TPR

VR

Question 19

NONprogressive (Compenasted) Hemorrhagic Shock

1. The sympathetic reflexes (baroreceptors, chemorecptors, ischemic response, etc.) plus the release of the _____________(norepinepherine and epinepherine) provide rapid response within 30 sec. for vasoconstriction of blood vessels.

Answer 19

catecholamines

Question 20

PROGRESSIVE Hemorrhagic Shock

1. As ___ becomes depressed, the progressive stage begins and becomes a vicious circle
2. Vasomotor Center Failure
3. Blockage of Small Vessels by “____ _______”
4. Release of Toxin from Ischemic Tissue—diminished blood flow to the intestines creates toxins released from the bacteria. These circulating toxins cause further cardiac depression. _________ is one of the specific
   toxins specified in hemorrhagic shock and septic shock.
5. Cellular Deterioration–Cells in the______ are especially
   vulnerable because of its function to filter toxins and metabolic waste products. It requires a high blood flow to maintain its functions

Answer 20

CO

Sludged Blood

Endotoxin

liver

Question 21

Treatment of Progressive Hemorrhagic Shock

1. ________ ________of whole blood is best along with administering electrolyte solution to correct dehydration.
2. If whole blood is not available, blood plasma can be used.
3. If plasma is not available, a plasma substitute solution called Dextran is used, which is a large polysaccharidepolymer of glucose.

Answer 21

Blood transfusion

Question 22

Irreversible Hemorrhagic Shock

1. When shock reaches a certain point, even a blood transfusion cannot save the person’s life.
2. However, even in the irreversible stage, AP and CO may be returned to normal values but _____ _______ has progressed so far that it can’t be reversed and death will occur within minutes to a few hours
3. Depletion of ATP—ATP is degraded to ADP, AMP and eventually adenosine

Answer 22

organ damage

Question 23

Neurogenic Shock

This occurs WITHOUT blood loss, instead vascular capacity increases so much that the normal volume of blood cannot fill the circulatory system adequately. It results from a sudden loss of vasomotor tone so all the veins _________ which results in venous pooling and a significant decrease in _______

Answer 23

vasodilate

VR.

Question 24

Anaphylactic or Histamine Shock

____________ is a severe allergic reaction that significantly depresses CO and AP.

_______- are released because of the antigen-antibody reaction. This occurs rapidly after the antigen to which the person is extremely sensitive to is released into circulation.

• Some with severe reaction to the antigen can die within minutes.
• Treatment is injection of epinepherine (epi pen) to cause _____________

Answer 24

Anaphylaxis

Histamines……AND… histamines cause:

1. INCREASE in VENOUS dilation (vascular capacity) which decreases VR
2. DILATION of the ARTERIOLES which reduces AP
3. Increased capillary permeability so fluid loss and plasma protein loss which decreases VR

constriction

Question 25

Septic Shock

1. Often called “_____ __________”. This results from bacterial infection invading many areas of the body with infection being spread from one tissue to the next
   via the blood.
2. Next to CARDIOGENIC SHOCK, septic shock is the second most common way to die of shock in the hospital.

Answer 25

blood poisoning

Question 26

Types of Septic Shock x 5

1. __________- from spread of infection from uterus or fallopian tubes—usually from abortions preformed with unsterile instruments
2. Peritonitis from rupture of GI system caused by intestinal disease or from a wound
3. Spread of ____ infections such as streptococcal or staphylococcal infections
4. Gangrene spread from _________ tissues—finds it way via the blood into the liver
5. Infection getting into the _______ spreading from the kidneys, urinary tract or colon

Answer 26

Peritonitis

skin

peripheral

blood

Question 27

Symptoms of Septic Shock x 5

1. _________ fever
2. Marked _________ throughout the body but especially in infected areas
3. High CO because of vasodilation in infected tissues
4. Sludging of blood with toxins and RBC agglutination in response to tissue deterioration
5. Development of micro-blood clots (called disseminated intravascular coalgulation) so blood clotting factors are used up so hemorrhaging often occurs in the intestinal tract.

Answer 27

High

vasodilation