Cardiac & Bronchodialators

Question 1

Digitalis MOA

Answer 1

-inhibits Na/K ATPase in myocardium = ↑Na = ↑activity of Na/Ca exchanger = ↑Ca
-Leads to: ↑ino, ↑EF, ↓preload, ↓AV node conduction, ↓SA node automaticity

Question 2

Digitalis therapeutic index

Answer 2

0.8-2 ng/ml
toxic > 2.4

Question 3

Digitalis SE

Answer 3

-arrhythmias (Vfib, AV block)
-↓QT
-cardiotoxic (↑risk w/ ↓K)

Question 4

Digitalis drug interactions

Answer 4

-quinidine
-CCB
-NSAIDS
-amiodarone
-BB
-diuretics

Question 5

Digitalis and electrolytes

Answer 5

-↓K = ↑dig binding to Na/K ATPase = ↑therapeutic & toxic effects
-↑Ca = ↑digitalis-induced ↑Ca = Ca overload & digitalis-induced arrhythmias
-↓Mg = sensitizes heart to digitalis-induced arrhythmias

Question 6

Digitalis Contraindications

Answer 6

-↓K
-WPW
-AV block
-renal dysfx
-harmful in pt w/HSS

Question 7

What sympathomimetics are not metabolized by reuptake and MAO & COMT

Answer 7

-isoproterenol & dobutamine (COMT only)
-ephedrine (liver, mostly excreted renal unchanged)

Question 8

Epinephrine receptor & dosing

Answer 8

B1>B2, a1
0.01-0.2 mcg/kg/min
1-20 mcg/min

Question 9

NE receptor & dosing

Answer 9

a1, B1 > B2
0.01-0.2 mcg/kg/min
4-16 mcg/min

Question 10

Dopamine receptor & dosing

Answer 10

B1>B2, a1
2-20 mcg/kg/min

Question 11

Isoproterenol receptor & dosing

Answer 11

B1 > B2
0.015-0.15 mcg/kg/min
1-5 mcg/min

Question 12

Dobutamine receptor & dosing

Answer 12

B1>B2>a1
2-20 mcg/kg/min

Question 13

Ephedrine receptor & dosing

Answer 13

a, B indirect
bolus 5-25 mg IV
up to 50 mg IM

Question 14

Isoproterenol clinical effect

Answer 14

Pure beta agonist
- ↑ HR, contractility, CO
-↓ PVR, DBP
-↑MVO2 demand while ↓ O2 supply

Question 15

Dobutamine clinical effect

Answer 15

Selective B1 agonist
-↑ contractility, CO, cAMP, Ca in SR
-↓ PVR (B2)
-↓ LV filling pressure –> ↑coronary BF
-stimulates SA, AV nodal automaticity

Question 16

PDE inhibitor MOA

Answer 16

↑cAMP & ↑cGMP

Question 17

Clinical indication for PDE 3 vs 4 vs 5

Answer 17

-PDE3 = ↑ cAMP & ↑ cGMP (milrinone, cilostazol, amrinone) = inodilators
-PDE4 = ↑ cAMP (roflumilast, apremilast, ibudilast) = help w/ inflammatory states
-PDE5 = ↑ cGMP (sildenafil, tadalafil, vardenafil) = pulm vasodilation

Question 18

PDE inhibitor SE

Answer 18

-block plt aggregation
-ventricular arrhythmias
-HA
-HoTN
-flushing

Question 19

Inhaled beta-agonist MOA

Answer 19

b2 agonist = ↑cAMP = ↓Ca; stabilizes mast cell

Question 20

Inhaled beta-agonist SE

Answer 20

-tremor
-↑HR
-hyperglycemia
-↓K
-↓Mg
-dysrhythmias

Question 21

Inhaled muscarinic antagonist MOA

Answer 21

M3 antagonist = ↓IP3 = ↓Ca

Question 22

Inhaled muscarinic antagonist short vs long acting

Answer 22

-ipratropium (short)
-tiotropium (long)

Question 23

Methylxanthines (theophylline, aminophylline) MOA

Answer 23

PDEi = ↑cAMP & ↑cGMP; inhibit leukotriene; adenosine receptor antagonist

Question 24

Dose based SE for Methylxanthines

Answer 24

> 20 mcg/ml: N/V/D, HA, insomnia
30 mcg/ml: sz, arrhythmias, CHF

Question 25

Nonselective vs selective alpha antagonist

Answer 25

Non: phenoxybenzamine, phentolamine
a1: -zosin
a2: yohimbine

Question 26

Phentolamine dose

Answer 26

bolus: 1-5 mg
infusion: 0.1-0.2 mg/min

Question 27

Beta antagonist SE

Answer 27

-heart block
-HF
-AV block
-sinus arrest
-HoTN
-bronchospasm (asthma)

Question 28

What beta antagonist are not metabolized by the liver

Answer 28

Esmolol (hydrolysis of RBCe)
Atenolol (renal)

Question 29

Labetalol

Answer 29

-a1, B1, B2 (1a:7B)
-mixed blockade↓ PVR, ABP w/o reflex tachy
-IV peak 5 min
-Dose: 0.1-0.25 mg/kg q 10 min

Question 30

Class I antidysrhythmic SE

Answer 30

-cinchonism
-cardiotoxicity
-arterial embolism
-hypersensitivity rxn

Question 31

Class I antidysrhythmic MOA

Answer 31

-depresses phase 0
-mixed effects on phase 3 repolarization

Question 32

Class IA antidysrhythmic

Answer 32

-Quinidine
-procainamine
-disopyraminde
-moricizine

Question 33

Class IB antidysrhythmic

Answer 33

-Lidocaine
-Tocainide
-Mexiletine

Question 34

Class IC antidysrhythmic

Answer 34

-Flecanide
-Propafenone

Question 35

Class II antidysrhythmic

Answer 35

Beta blockers

Question 36

Class II antidysrhythmic MOA

Answer 36

-slows phase 4 depolarization in SA node

Question 37

Class III antidysrhythmic MOA

Answer 37

-prolongs phase 3 repolarization (↑QT)
-↑effective refractory period

Question 38

Class III antidysrhythmic SE

Answer 38

-pulmonary/thyroid/CV/dErm toxic
-optic neuropathy
-corneal microdeposits

Question 39

Class III antidysrhythmic

Answer 39

↓K
-amiodarone
-sotalol
ibutilide
-dofetilide
-bretylium

Question 40

Class IV antidysrhythmic

Answer 40

CCB:
-Verapamil
-Diltiazem

Question 41

Class IV antidysrhythmic MOA

Answer 41

↓conduction velocity through AV node

Question 42

Adenosine MOA

Answer 42

↓AV node conduction d/t K efflux (hyperpolarizes); 6 > 12 mg

Question 43

Non-dihydropyridines vs Dihydropyridines

Answer 43

Non-dihydropyridines
-verapamil, diltazem
- Target myocardium = ↓coronary vascular resistance, ↓ino, ↓dromo, ↓chrono
Dihydropyridine
- -dipine
-Targets vascular smooth muscle = ↓SVR

Question 44

CCB SE

Answer 44

-inhibit inflow of Ca into cells of cardiac & vascular smooth muscle

Question 45

CCB Drug Interactions

Answer 45

-potentiate NMB & LA
-vasoplegic synd
-may ↑dig levels
-BB
-HoTN, CHF, asystole, high-degree AV block w/ BB and dig