Mechanism of Action

Question 1

Adenosine

Answer 1

Slows conduction time through AV
Slows sinus rate
Interrupts reentrance
Large doses decrease BP

Question 2

Albuterol

Answer 2

Beta agonist primarily B2
Relaxes bronchial smooth muscle, bronchodilates
Relaxes vascular and uterine smooth muscle
Decreases airway resistance

Question 3

Amiodarone

Answer 3

Slows membrane depolarization and conduction (sodium channels)
Slows ventricular automaticity (potassium channels)
Negative chronotropic effect in nodes (calcium channels)
Antisympathetic
Dilates coronary arteries

Question 4

Aspirin

Answer 4

Blocks thromboxane A2 (platelet aggregate, vasoconstrictor)

Decreases platelet aggregation

Question 5

Atropine

Answer 5

Blocks the action of acteylcholine as a competitive antagonist at muscarinic, secretory, and CNS receptors. Allows sympathetic to take over.

Question 6

Calcium Chloride

Answer 6

Stimulates release of catecholamines
Positive inotropic effect
Enhances ventricular automaticity
Inhibits the effect of adenosine on mast cells

Question 7

Dextrose

Answer 7

Aerobic metabolic substrate (ATP production)
Rapidly increases serum glucose levels
Short term osmotic diuresis

Question 8

Diltiazem

Answer 8

Inhibits calcium ion influx
Decreases SA and AV conduction
Dilates coronary and peripheral arteries/arterioles
Reduces vascular resistance

Question 9

Diphenhydramine

Answer 9

Blocks cell histamine receptors
Some anticholinergic effects
Decreases capillary permeability and vasodilation
Prevents bronchospasm

Question 10

Dopamine

Answer 10

1-2 mcg/kg- Stimulates cerebral, renal, mesenteric vasculature to dilate
2-10 mcg/kg-B1 stimulant increases cardiac output and some vasoconstriction
10-20 mcg/kg- Increased systemic vasoconstriction
Over 20- Acts like norepi, increase HR and 02 demand to undesirable rates

Question 11

Epinephrine

Answer 11

Vasoconstrictor
Bronchodilator
Powerful Alpha and Beta stimulator

Question 12

Glucagon

Answer 12

Converts glycogen to glucose in liver
Cardiac inotrope
Relaxes GI smooth muscle

Question 13

Ipatropium Bromide

Answer 13

Anticholinergic

Dilates larger central airway (large bronchioles)

Question 14

Lidocaine

Answer 14

Decreases automaticity by slowing spontaneous depolariztion
Terminates reentry by interrupting pathways
Increases VF threshold

Question 15

Magnesium Sulfate

Answer 15

Reduces ventricular irritability
Inhibits muscular excitability
Helps potassium enter the cell, important role in neurotransmission

Question 16

Morphine

Answer 16

Elevates pain threshold
Depresses CNS and brainstems response to CO2
Increase venous capacity, vasodilates
Histamine release

Question 17

Naloxone

Answer 17

Competitive narcotic agonist

Reverses respiratory depression due to narcotics

Question 18

Nitro

Answer 18

Smooth muscle relaxant
Decreases preload and afterload, increase blood pooling
Increases blood flow to myocardium
Decreases myocardial 02 demand

Question 19

Solu-Medrol

Answer 19

Stabilizes cellular and intracellular membranes leading to decreased inflammation

Question 20

Thiamine

Answer 20

Required for carbohydrate metabolism

Deficiency leads to anemia, polyneuritis, wernickes encephalopathy, cardiomyopathy

Question 21

Versed

Answer 21

Blocks GABA receptors
Acts on limbic, thalamic, and hypothalamic levels of the CNS causing sedation/hypnotism/anticonvulsant
CNS depression

Question 22

Zofran

Answer 22

Blocks serotonin 5-HT3 receptors located in the CNS at the chemoreceptor trigger zone in the nerve terminals of the vagus nerve