Drugs to treat Aortic Dissection

Question 1

2 mechanisms by which Beta Blockers work

Answer 1

1. Decrease sympathetic effects on the heart

2. Relax vascular smooth muscle to cause vasodilation

Question 2

Labetalol

Answer 2

• Nonselective anti-andrenergic (alpha and beta action)

- Decreases PVR without effect on rate or contractility

Question 3

Contraindications for Labetalol

Answer 3

> 1 degree heart block
Bradycardia
Shock
Hypotension

Question 4

Unique adverse effect of Labetalol

Answer 4

Tingling scalp or skin

Question 5

Relative Contraindications of Labetalol

Answer 5

1. Hepatic Injury
2. Bronchospasm (B2 blocking effects)
3. Pheochromocytoma
4. Bedus

Question 6

Drug interactions with labetalol

Answer 6

1. Antidepressants (cough.. Allison)
2. Cimetdine (H2 blocker)
3. Halothane Anesthesia
4. Nitro
5. CCB (Virapamil)

Question 7

Things to be aware of in elderly populations and pregnant women when using Labetalol

Answer 7

Elderly- decreased clearance

Pregnancy- increased clearance and maybe risk to fetus

Question 8

Esmolol

Answer 8

Selective B1 blocker (Class II anti arrhythmic)

• Decreased heart rate and contractility
• Used during procedures to control BP and Tachycardia

Question 9

Contraindications of Esmolol

Answer 9

1. Asthma
2. Shock
3. Bradycardia
4. Hypotension

Question 10

Unique features of Esmolol

Answer 10

1. very short half life (9m)
2. Do NOT abruptly stop
3. Vesicant (blisters the skin so beware of administration route)
4. May cause Hyperkalemia and lead to arrhythmias
5. Erythrocytic

Question 11

Potential issue of Esmolol use in pregnancy

Answer 11

1. Continued fetal bradycardia

If indicated for mother, fetal growth should be monitored and the baby should be monitored for 2 days after birth

Question 12

Nitroprusside

Answer 12

Nitrate drug class

- causes vascular smooth muscle dilation and decreases PVR

Question 13

What is the MOA of nitrates?

Answer 13

1. NO activates Guanylate Cyclase
2. GC increases cGMP
3. cGMP activates phosphatase
4. Phosphatase inhibits Myosin light chain
5. No muscle contractions

Question 14

What should be monitored in a person given nitroprusside?

Answer 14

Sweet, Sweet, Cyanide!

- Nitroprusside produces low levels of cyanide, but too much too fast can overcome clearance rate and cause poisoning

Question 15

Contraindications for nitroprusside

Answer 15

1. B12 def
2. Anemia
3. Renal Dz
4. Hypovolaemia
5. Acute CHF

Question 16

Side effects of Nitroprusside (common ones)

Answer 16

1. HA
2. Sweating
3. Restlessness
4. Hypotension

Question 17

What can be given if cyanide levels are high?

Answer 17

Sodium Thiosulfate

Question 18

Metabolism of nitroprusside

Answer 18

4 molecules of CN- per 1 molecule of nitroprusside

Question 19

Elimination of cyanide

Answer 19

Metabolized to thiocyanate and eliminated in urine

Question 20

Nicardipine

Answer 20

CCB (dihydropyridine aka non-cardioactive)

Does not change serum Ca2+ levels

Question 21

Indications for Nicardipine

Answer 21

short term treatment of HTN

prolonged treatment of BP

Question 22

What population is nicardipine contraindicated in?

Answer 22

Advanced aortic stenosis

Question 23

Side effects of Nicardipine

Answer 23

HA
Hypotension
Tachy
NV

Question 24

Considerations for Nicardipine

Answer 24

1. Angina pt’s- can increase frequency and duration
2. HF- titrate slowly and mix with a beta-blocker
3. Hepatic injury- be cautious

Question 25

2 drugs to consider interactions with when administering nicardipine

Answer 25

1. Cyclosporine
2. Tacrolimus
   CYP3A4 saturation