Antidysrhythmics drugs Flashcards
How do Na+ Channel Blockers work?
Decreased conduction velocity through the myocardium
Na+ Channel Blockers: Quinidine & Procainamide= What do they do?
delay repolarizartion
Na+ Channel Blockers: Lidocaine & Phenytoin = What do they do?
accelerate repolarization
How do Beta Blockers (-OLOL) work?
Block binding of epi/norepi in nodal
and non-nodal tissue
Decrease SA node automaticity
Inhibit AV response by prolonging
refractory period and slowing conduction
Adverse effects of Beta Blockers ?
bradycardia, hypotension, fatigue
Beta blockers are frequently given for ….
A Fib
How do K+ channel blockers work?
Na+ and Ca++ channels become inactivated, allowing K+ to leave the cells = repolarization
K+ channel blockers are used in emergencies during….
Ventricular tachycardia
How do Ca++ channel blockers work?
Decrease conduction velocity
Prolong repolarization
Act mainly at the AV node; also decrease ectopic beats
What does Adenosine do?
Vasodilation
binds to A1 receptors–>activates opening of K+ channels –> hyperpolarization, inhibition of pacemaker cells
Adenosine is given when…
supraventricular tachycardia
How long is Adenosine half life?
10 seconds
You should never give Digoxin with what other drug?
Loop diuretics
When taking Verapamil (Ca channel blocker) there is a high risk for toxicity when taking what other drug?
Digoxin
When is the only time you would give Lidocaine IV?
when a patient is in V Tach and it is a life or death kinda situation
