Acute Cardiac Flashcards
Nitroprusside–clinical use
hypertensive emergency
nitroprusside–mechanism
short acting
increases cGMP via direct release of NO
nitroprusside–toxicity
releases cyanide, so can lead to cyanide toxicity
what are the class IA antiarrhythmic drugs?
Quinidine, Procainamide
class IA antiarrhythmics–mechanism
inc AP duration
inc effective refractory period (ERP) in ventricular action potential
inc QT interval
class IA antiarrhythmics–use
both atrial and ventricular arrhythmias, especially re-entrant and ectopic SVT and VT
class IA antiarrhythmics–toxicity
cinchonism–headache, tinnitus with quinidine
reversible SLE like syndrome (procainamide)
torsades de pointes due to inc QT interval
what are the class IB antiarrhythmic drugs?
Lidocaine
MexileTine
“I‘d Buy Liddy’s Mexican Tacos”
class IB antiarrhythmics–use
acute ventricular arrhythmias (especially post MI)
digitalis-induced arrhythmias
“IB is Best post MI”
class IB antiarrhythmics–toxicity
CNS stimulation/depression
cardiovascular depression (heart blocks, altered AV conduction)
what is the best antiarrhythmic drug to use for a post MI patient?
class IB
what are the class IC antiarrhythmic drugs?
Flecainide
Propafenone
“Can I have Fries, Please?”
which class IA antiarrhythmic drug may cause digoxin toxicity?
Quinidine–decreases digoxin clearance and displaces digoxin from tissue binding sites
class IC antiarrhythmics–use
SVTs, including atrial fibrillation
only as a last resort in refractory VT
do not affect AP duration
when are class IC antiarrhythmics contraindicated?
structural heart diseases and post MI
what are class II antiarrhythmics?
name 5
beta blockers
propranolol
atenolol
metoprolol
labetolol
carvedilol
class III antiarrhythmics–mechanism
Alteration of lipid membrane in which ion channels and receptors are located
what are class III antiarrhythmics and name 4
potassium channel blockers
Amiodarone
Ibutilide
Dofetilide
Sotalol
“AIDS”
class III antiarrhythmics–use
atrial fibrillaiton
atrial flutter
ventricular tachycardia (amiodarone, sotalol)
what is the indication for class III antiarrhythmics?
when all other antiarrhythmics fail
sotalol toxicity
(class III antiarrhythmic)
torsades de pointes
excessive beta blockade
ibutilide–toxicity
(class III antiarrhythmic)
torsades de pointes
amiodarone–toxicity
(class III antiarrhythmic)
pulmonary fibrosis
hepatotoxicity
hypothyroidism/hyperthyroidism (amiodarone is 40% iodine by weight)
acts as hapten–corneal deposits, blue/gray skin deposits causing photodermatitis
neurologic effects
cardiovascular effects–bradycardia, heart block, HF
