CV Function in Pathology - Nordgren Flashcards

1
Q

What is circulatory shock?

A

Generalized, severe reduction in blood supply to the body tissues.

  • metabolic needs of tissues not met
  • arterial pressure usually low
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the primary disturbances that can account for cariogenic, hypovolemic, anaphylactic, septic, and neurogenic shock states?

A
  • Severely depressed myocardial functional ability
    • cardiogenic shock
  • Grossly inadequate filling due to low mean circulatory filling pressure
    • hypovolemic shock
  • Profound systemic vasodilation
    • anaphylatic shock
    • septic shock
    • neurogenic shock
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the compensatory processes that may arise during various types of circulatory shock?

A
  • Greatly increased sympathetic nerve activity
    • pallor, cold/clammy skin, rapid HR, muscle weakness, venous restriction
  • Abnormally low arterial pressure, reduced cerebral perfusion –> dizziness, confusion, LOC
  • Rapid/shallow breathing –> increase VR (respiratory pump)
  • Increased levels of epinephrine
  • Reduced capillary hydrostatic pressure resulting from intense arteriolar constriction –> reabsorption
  • Increased glycogenolysis in the liver (via Epi/NE)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the renal compensatory processes that may arise during various types of circulatory shock?

A
  • Increased RENIN release →
    • increased TPR via formation of angiotensin II (vasoconstriction)
  • Increased circulating levels of ADH →
    • increased TPR (fluid retention)
  • Increased circulating levels of Aldosterone →
    • Na+ & fluid retention
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the decompensatory processes that may arise during shock and describe how these lead to irreversible shock states?

A
  • Arteriolar vasoconstriction
    • can lead to severely reduced perfusion of other tissues → possibly damage organs
  • Bodily homeostasis deteriorates with prolonged reductions in organ flow
    • adversely impacts CV system → further reduces flow
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How may coronary artery disease lead to abnormal cardiac function?

A
  • Atherosclerosis of the large coronary arteries leads to:
    • permanently increased vascular resistance → reduced coronary flow
    • arrhythmias
    • heart failure
    • MI
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the difference between Progressive shock and Irreversible shock?

A
  • Progressive:
    • general CV situation progressively degenerates
  • Irreversible:
    • no intervention can halt the ultimate collapse of the CV system → DEATH
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Define the term “heart failure”.

A

Depressed ventricular function due to myocardial damage, insufficient coronary flow, or anything that directly impairs mechanical performance.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the difference between systolic and diastolic failure?

A
  • Systolic:
    • Left ventricular EF <40% (reduced CO at any given filling pressure)
    • Reduced myocyte function
    • 1° disturbance = decreased CO → decreased arterial pressure
    • cause edema & congestion
  • Diastolic:
    • stiffened heart during diastole
    • increases in cardiac filling pressure do not produce normal increases in EDV
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the short-term and long-term compensatory processes that accompany chronic systolic heart failure?

A
  • Short-term:
    • Increased sympathetic activity
    • Rapid breathing
  • Long-term:
    • Rise in blood volume (renin release)→ increased mean circulatory filling pressure
    • Fluid retention causes increased peripheral and central venous pressures
      • cardiac dilation → increased myocardial O2 demand
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the advantages and disadvantages of the fluid accumulation that accompanies systolic heart failure?

A
  • Pro:
    • ↑sympathetic activity (short-term) → ↑blood volume → ↑mean circulatory filling pressure
    • ↑CO closer to normal and allows reduction of sympathetic activity
      • when enough fluid has been retained, normal CO can be achieved with normal sympathetic nerve activity
  • CON:
    • fluid retention → ↑ peripheral and central venous pressure → chronically high EDV
      • causes excessive cardiac dilation → impairs function due to ↑ total wall tension/stress required to generate adequate pressure
      • increased myocardial O2 demand
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the difference between pulmonary and systemic arterial hypertension?

A
  • Pulmonary:
    • pulmonary artery pressure >20mmHg
    • systemic edema, chest pain, fatigue
    • linked to chronic hypoxia (COPD, cystic fibrosis)
  • Systemic:
    • elevation of mean systemic arterial pressure > 140/90 mmHg
    • >20% of adult western world pop’n
    • increased risk of CAD, MI, heart failure, stroke, etc.
    • primary OR essential
How well did you know this?
1
Not at all
2
3
4
5
Perfectly