L68 Flashcards Preview

P&T Block 3 Pulm & GI > L68 > Flashcards

Flashcards in L68 Deck (29):
1

Describe typical pulm HTN pt

Young - 35 y.o.
2x more women
Long latent - 2 yrs of symptoms before dx

2

Is pulm HTN venous or arterial?

Arterial - duh!
B/c happening on the entry side into the lungs (but this is venous blood)
Think about it... makes sense

3

Define pulm HTN
- Mean pulm art pressure
- Pulm catheter wedge pressure = LVEDP
- Pulm vasc resistance
How do you get these values?

MPAP > 25 mm Hg
(12 - 18)
LVEDP 3 wood units
(

4

Low or high?
Resistance in pulm circulation
Compliance in pulm vascular bed

Low resistance
High compliance
Impt b/c receiving the entire CO!!

5

What happens to pulm vasculature during exercise?

Increase flow + vaso dilation + recruitment
Net decrease pulm vasc resistance

6

What are the 4 changes to vasculature in PAH?

1. Vasoconstriction
2. Endothelim and smooth muscle cell prolif
3. Thrombosis
4. Plexiform lesions = tuft of cells where artery lumen should be

7

What are the end stage lesions in PAH?

Plexiform lesions

8

What neurohormone is abnormally high in PAH?

Endothelin 1
- Vasoconstrict
- SM prolif
- Prothrombosis

9

What neurohormones are abnormally low in PAH?

Prostacyclin
NO
Net:
- Vasodilation
- Control cell prolif
- ↓platelet aggregation

10

How is NO made?

Arginine + NO synthase

11

How does prostacyclin vs NO vasodilate?

Prostacylcin = ↑cAMP
NO = ↑cGMP

12

What is bone morphogenetic protein receptor 2?

Genetic mutation associated with PAH
Mutated -> ↑apoptosis -> ↑cell prolif in vasc SM

13

PAH pt presentation

DOE
Dizziness
Chest pain / palpitations
Leg edema
Syncope - hemodynamic collapse

14

PE findings PAH

R heart strain:
- Loud P2
- Tricuspid regurg
- Pulm regurg
Fluid backup due to ineffective pumping:
- JVD
- Hepatomegaly
- LE edema
- Ascites

15

3 CXR findings for PAH

1. Peripheral lung vessels are hard to see b/c ↓BF
2. Large prox pulm arteries
3. (On side view) RV enlargement forward into retrosternal space

16

EKG for PAH in early vs late disease (4)

Early = normal
Late
1. R axis deviation
2. RA enlargement
3. RV hypertrophy
4. RV strain

17

PAH on echo

Size of the R and L heart switched
R = huge
L = small

18

What valve might show regurg on echo with PAH?

Tricuspid
Due to high pressures, RV spits back into RA

19

What is the best way to screen for PAH? What do you need to do to definitively dx?

Best screening = ECHO
Dx need catheterization! (int jug vein)

20

What is the idea behind giving prostacyclin derivatives?

PAH pts are low in prostacyclin
So add an analog
- ↑cAMP -> vasodilation
- Anti-prolif

21

Name 3 prostacyclin analogs

Epoprostenol - short
Treprostinil - longer
Iloprost - longer (inhaled)

22

Pros/cos to epoprostenol

Con = continuous IV infusion, if disconnect -> emergency
Pro = most effective therapy, survival benefit shown

23

Cons of treprostinil

Site rxn to subq infusions
- Can be given inhaled

24

What's the idea behind giving endothelin receptor antagonists?

Block the action of excess endothelin at receptor A + B
Some drugs are receptor specific vs others are non

25

2 endothelin receptor antagonists

Bosentan
Ambrisentan

26

Benefits and SE of Bosentan

Benefit = improve exercise capacity
SE:
- Monthly LFTs
- LE edema

27

Benefits and SE of Ambrisentan

Benefit = improve exercise capacity w/o need for LFTs
SE - worse LE edema

28

2 drug mechanisms to ↑cGMP

1. Exogenous NO - short half life, limited use outside hospital setting
2. PDE-I

29

2 PDE-Is you need to know. Both are contra-indicated with what?

Sildenafil
Tadalafil
CI w/ nitrates: similar mechanism of action -> hypotension