Antidysrhythmics III KAmiodarone

Question 1

action of antidysrhythmic drugs

Answer 1

depress contractility, excitability and automaticity; block adrenergic (sympathetic) simulation; incrase repolarization (phase to move to refractory/rest phase)

Question 2

define action potential

Answer 2

when there is movement of Na and K across cell membrane that causes depolarization/contraction

Question 3

define refractory phase

Answer 3

resting state; phase 4 of action potential; cell CANNOT respond to new stimulus; K is inside and Na is outside once again

Question 4

define automaticity

Answer 4

electrical impulse formation

Question 5

define excitability or irritability

Answer 5

cell CAN respond to stimulus

Question 6

define depolarization

Answer 6

muscle activated; contraction starts; systole to eject blood; Na rushing inside and Ca joined in, while K moving outside; phase starts at 0

Question 7

define repolarization

Answer 7

movement towards refractory/resting phase; K is completely out now; phase starts at 1 and plateaus at phase 2 and continues to phase 3 of action potential

Question 8

the phase between repolarization and refractory phase?

Answer 8

phase 3; magnesium activates the Na-K pump to fascilitate the movement of K back into the cell; Na and Ca move out; when complete, refractory phase 4 has been reached.

Question 9

define refractory phase

Answer 9

resting state; diastole to fill in with blood; phase 4 of action potential; cell CANNOT respond to new stimulus; K is inside and Na is outside once again

Question 10

class III Potassium channel blockers does this

Answer 10

prolong repolarization; K+ cannot get back in cell; prolong refractory period for atria and ventricles; slow HR

Question 11

class III potassium channel blocker is (x) line antidysrhythmic drug

Answer 11

2nd or 3rd line only

Question 12

example of class III potassium channel blocker

Answer 12

amiodarone

Question 13

class III amiodarone action

Answer 13

slow rate of depolarization and repolarization; decrease automaticity/electric formation; ACTS ON SODIUM AND CALCIUM CHANNELS ALSO

Question 14

class III amiodarone indication

Answer 14

SUPRAVENTRICULAR TACHYCARDIA (HR 100-300 bpm) aka PSVT; dysrhythmia originate from foci above the bifurcation of Bundle of His (could be AV or SA node problem); A. Fib/Flutter; pulseless ventricular tachycardia

Question 15

class III amiodarone a/e

Answer 15

HYPO/HYPERTHYROIDISM/thyrotoxicosis (amiodarone has iodine and has 100 days half life), PULMONARY FIBROSIS (BBW; s/s crackles, tachypnea, dyspnea on exertion; need steroid and lung transplant), myocardial depression, bradycardia, hypotension

Question 16

if pt is dizzy, do this

Answer 16

take VITALS SIGNS

Question 17

pulmonary fibrosis s/s

Answer 17

crackles, tachypnea, dyspnea on exertion

Question 18

do you need to take class III amiodarone forever?

Answer 18

nope

Question 19

class III amiodarone nsg responsibilities

Answer 19

this is a BBW even as PO route; half life persists for WEEKS; monitor liver and PULMONARY TOXICITY; need EKG

Question 20

class III amiodarone contraindication

Answer 20

COPD and respiratory insufficiency

Question 21

class III amiodarone drug interaction

Answer 21

simvastatin zocor d/t rhabdomyolysis potentiated