Pulmonary HTN

Question 1

pulmonary HTN

Answer 1

localized HTN in pulmonary circuit where you have sustained pulm arterial pressure > 25 mm Hg

Question 2

what makes the pulmonary circuit compliant?

Answer 2

*low resistance and low pressure

• minimal increase in pressure if CO increases
• pulmonary vasoconstriction causes an increase in pressure

Question 3

what is the normal pulmonary arterial pressure?

Answer 3

15 mm Hg

Question 4

etiology

Answer 4

• mostly secondary to cardiac and pulmonary issues
• 3 categories:
  
  1. Hypoxemia
  2. Increased pulmonary blood volume
  3. Increased pulmonary venous pressure

Question 5

explain etiology of hypoxemia

Answer 5

increased pressure in pulm circuit -> hypoxia in lungs will cause vasoconstriction

Question 6

explain etiology of increased pulm blood volume

Answer 6

septal defect causing blood in l. ventricle to leak back into r. ventricle through a hole in the interventricular septum that didn’t close during embryogenesis, resulting in increased blood volume travelling through the pulm circuit

Question 7

explain etiology of increased pulmonary venous pressure

Answer 7

mitral valve stenosis -> accum of blood -> congestion -> increased pressure

Question 8

patho

Answer 8

hypoxemia -> hypoxia in the lungs and hypercapnia in blood -> compensatory vasoconstriction occurs to prevent spread of increased CO2 throughout the body -> increased pressure w/in pulm circuit

Question 9

manifestations

Answer 9

• dyspnea
• fatigue
• syncope
• chest pain OE d/t increased RR = increased demand
• mnftns of RHF
• right ventricular hypertrophy (d/t increased workload requiring increased muscle size) and distended pulm arteries (d/t congestion of blood)

Question 10

why do you have mnftns of RHF?

Answer 10

b/c heart is pumping against increased resistance d./t increased pressure in the pulm arteries

Question 11

diagnosis

Answer 11

chest xray (would should hypertrophy and distention)

Question 12

treatment

Answer 12

vasodilators (Ca channel blockers or prostacyclin)

Question 13

Ca channel blockers

Answer 13

blocks Ca from moving across muscle cell membranes and activating sm constriction

Question 14

prostacyclin

Answer 14

• potent, pulm vasodilator that causes dilation of the r. ventricle
• r atrioventricular valve increases fx to prevent regurgitation
• lines endothelium and prevents attachment of cells
• also an antithrombolytic (but doesn’t apply here)