test 2 part 2

Question 1

Cardiac Failure caused by

Answer 1

 any condition that decreases ability of heart to pump enough blood to satisfy body’s needs
 Decreased contractility due to decreased coronary blood flow
 Damaged heart valves
 Pericardial disease
 Vitamin B deficiency
 Primary heart muscle disease

Question 2

How a person responds to an acute myocardial infarction (or other decrease in cardiac function)
depends on (2)

Answer 2

 How bad the cardiac insult is (i.e. how much does the person’s cardiac function curve shift down from normal) and how much cardiac reserve is left.
 Whether enough cardiac function is left so kidneys are able to maintain a normal balance between intake and output (i.e. maintain a relatively normal circulating blood volume).

Question 3

Cardiac reserve

Normal

Answer 3

5-13 L/min is 260% increase

Question 4

Cardiac reserve

hypereffective

Answer 4

5 L/min to 25 L/min is 500% increase

Question 5

Cardiac reserve

Hypereffective PLUS Hypertrophy

Answer 5

5 L/min to 30 L/min is 600% increase

Question 6

what causes a decrease in the reserve of the heart

Answer 6

 Any condition that results in a hypoeffective heart

Question 7

symptoms of a patient with hypoeffective heart

Answer 7

 Immediate shortness of breath – can be
extreme (not able to supply tissues with needed blood supply)
 Extreme muscle fatigue (muscle ischemia)
 Extreme increase in heart rate (created by increase in sympathetic tone)

Question 8

Cardiac reserve can be tested by

Answer 8

-stress test, either physical

or chemical

Question 9

Severe coronary thrombosis and severe valvular disease

Answer 9

-have no cardiac reserve and the CO isn’t high enough to support them at normal operation

Question 10

Normal renal function depends on

Answer 10

-the ability of the
body to maintain a normal
MAP and CO.

Question 11

If heart/body are not able to
maintain a normal MAP and
CO the kidneys will

Answer 11

-continually retain salt and
fluid. Renin-angiotensin
system play major role in this mechanism.

Question 12

Initial response to acute moderate failure (myocardial infarction)

Answer 12

• cardiac function curve moves down
• no change in venous return
• CO drops
• RAP increases

Question 13

ANS response to acute moderate failure

Answer 13

 Within seconds, the circulatory reflexes begin to
kick in (Baro, Chemo, and CNS response)
 Both the cardiac and venous function curves are
affected
-increased heart rate and contractility
-Increased venous constriction increases mean systemic filling pressure
-CO increases
-RAP increases
-patient is okay

Question 14

Chronic stage of acute moderate failure

Answer 14

• CO still too low so kidneys begin to retain salt and water
• heart begins to recover
• CO increase
• RAP increases
• Since CO normal, renal function returns to normal so no further increase in CBV

Question 15

effect of the cardiac and venous function curves by chronic stage acute moderate failure

Answer 15

 Shift cardiac function curve up as damaged tissue heals increasing overall performance
 Shift venous function curve to right as mean systemic filling pressure increases
 Shift slope of venous function curve up as veins stretched by increased volume

Question 16

What if the failure is severe?

Answer 16

 If the failure is severe enough, person’s heart/system will not be able to compensate
 If kidneys continue to hold onto salt and water, the person’s heart and cardiovascular system will quickly decompensate.

Question 17

Decompensated cardiac failure (renal output is not normal and there is NO further increase in cardiac function)

Answer 17

 Kidneys continue to hold onto salt and water
 CBV continues to increase
 Mean systemic filling pressure continues to increase
 Venous function curve continues to move to the right
 RAP continues to increase pushing cardiac performance farther to right on curve
 End result is cardiac deterioration and development of cardiogenic shock

Question 18

Pharmacological treatment of sever failure

Answer 18

 Increase cardiac function
-inotropic agents
-increase BP to increase coronary Q
-Vasodilator/inotropic combination to increase cardiac performance and reduce SVR
 Increase urine output
 Decrease salt and water intake

Question 19

Treat original cause of cardiac failure

Answer 19

 Re-establish blood flow to ischemic heart
-Drugs that breakdown clots
-Balloon angioplasty
-Stents
-Coronary artery bypass grafts
 Repair / replace damaged valve
 Replace the heart

Question 20

Left side failure with normal right side function will increase overall volume in the pulmonary circulation

Answer 20

 Produces increase in mean pulmonary filling pressure
 Produces increase in mean pulmonary capillary pressure
 Once pulmonary edema begins to form, the volume of fluid can increase so rapidly that the patient can “drown” in 20 to 30 minutes

Question 21

when does peripheral edema begin to form

Answer 21

 Peripheral edema begins to form during the compensatory stage when reduced renal function results in an increase in CBV and an increase in the mean systemic filling pressure

Question 22

causes of increase in CBV

Answer 22

 Decreased glomerular filtration rate
 Activation of renin-angiotensin system
 Increased aldosterone secretion
 Increase sympathetic tone
-Constriction renal afferent arterioles
-Stimulates increased renal tubular reabsorption of salt and water
-Stimulation of renin release
-Stimulation of antidiuretic hormone release

Question 23

Pulmonary edema can be lethal

Answer 23

 As fluid leaks into interstitial spaces and alveoli, ability to transfer oxygen is compromised
 Decreased oxygen in the blood means less oxygen available to the heart which exacerbates the decrease in cardiac function
 Decreased oxygen in the blood leads to peripheral vasodilation and an increase in venous return

Question 24

how to treat pulmonary edema

Answer 24

Fix the left hearts function

Question 25

Lack of vitamin B1

Answer 25

• Peripheral vasodilation starts the process – leads to salt / water retention – leads to overuse damage to heart