antidysrhythmics Flashcards
What are cardiac dysrhythmias?
They are any deviation from a normal HR or pattern that slow down conduction in the heart.
What are cardiac dysrhythmias caused by?
MI, hypoxia, hypercapnia, thyroid disease, CAD, electrolyte imbalance, hyper/hypo kalemia and magnesemia.
What are the types of antidysrhythmics?
Sodium channel blockers, Beta blockers, Potassium channel blockers (amiodarone), Calcium channel blockers (verapamil and diltiazem).
How do sodium channel blockers work?
They decrease sodium influx into cardiac cells, which decreases conduction and ectopy (extra beats).
Which sodium channel blocker meds are used for PAT and SVT?
Quinidine, Procainamide, Disopyramide.
Which sodium channel blockers are used for VT and VFIB?
Lidocaine, Flecainide, Mexitiletine HCL.
How do beta blockers work?
They decrease conduction velocity, improve automaticity and recovery time, and decrease afib, tachycardia, and dysrhythmias.
What beta blockers are used as antidysrhythmics?
Acebutolol (Sectral) and Sotalol.
What is sotalol used for?
Mostly used for patients with AFIB.
What is acebutolol (Sectral) used for?
It is a B1 blocker, used more for patients with ventricular dysrhythmias, angina, and HTN.
What pregnancy category is acebutolol (Sectral)?
Pregnancy category B.
What are the contraindications of acebutolol (Sectral)?
2nd/3rd degree heart block, severe bradycardia, severe HF, and cardiogenic shock.
In what patients should we take caution with when giving acebutolol (Sectral)?
Patients undergoing major surgery, patients with renal/hepatic impairment, patients with Labile Mellitus.
What drug interactions occur with acebutolol (Sectral)?
Increased effects with diuretics, prolonged hypoglycemia, antagonist effect with albuterol, terbutaline, and metaproterenol. May also increase ACT, AST, ALP, BUN and K+.
What are the side effects of acebutolol (Sectral)?
Dizziness, nausea, headache, fatigue, hypotension, diaphoresis.
What are the adverse effects of acebutolol (Sectral)?
Palpitations with abrupt discontinuation, and bradycardia.
What are life threatening effects of acebutolol (Sectral)?
Agranulocytosis and bronchospasm with high doses.
How do potassium channel blockers work?
They increase refractory period and prolong action potential.
Which potassium channel blocker is used as an antidysrhythmic?
Amiodarone (Codarone).
What is Amiodarone (Codarone) used for?
Mostly used for AFIB, but can also be used in a code situation when a patient has VTACH or VFIB.
What tests should be taken, when, and why?
Thyroid and pulmonary function tests at beginning of treatment, 6 months in, and then yearly, because it can cause hypothyroidism and pulmonary fibrosis.
How do calcium channel blockers work?
They block calcium influx, decreasing cardiac response and conduction.
What are the ONLY calcium channel blockers used as antidysrhythmics?
Verapamil and diltiazem.
What are the contraindications of calcium channel blockers?
Heart block, severe bradycardia, heart failure.
