We continue our series on Cardiac Drugs –
You can find part one of the series here – http://www.nclexreviewonline.com/cardiac-drugs-for-nclex-part-1/
Part 2 is here – http://www.nclexreviewonline.com/nclex-cardiac-drugs-part-2/
Anticholinergic Effects
- Dry Mouth
- Urinary retention
- Constipation
- Tachycardia
- Blurred vision
- Mydriasis
Antidysrhythmics
(Class IB: Na+-Channel Blockers)
Expected Action:
decreased conduction / decreased automaticity / increased repolarization rate
Sodium channel blockers: lidocaine (Xylocaine)
Therapeutic Uses:
Short-term use only for ventricular dysrhythmias
Adverse Effects:
Respiratory arrest
CNS effects (fatigue, paresthesias, seizures)–Tx seizures ĉ phenytoin (Dilantin)
Contraindications/Precautions:
- CI: Stokes-Adams, Complete ♥ block
Pregnancy (B)
Interactions:
Cimetidine, phenytoin, β-Blockers leads to increased effects of lidocaine.
Education:
Never administer lidocaine that has epinephrine in it.
Loading dose followed by maintenance dose of 1-4 mg/min.
Antidysrhythmics
(Class IV: Ca2+-Channel Blockers)
Expected Action:
decreased force / decreased HR / decreased AV node conduction
Calcium-channel blockers: verapamil (Calan), diltiazem (Cardizem)
Therapeutic Uses:
Atrial fibrillation, SVT, Atrial flutter
Adverse Effects:
Orthostatic hypotension, peripheral edema, constipation, cardiac suppression, dysrhythmias, acute toxicity
Interactions:
Digoxinleads toincreased[digoxin]
Grapefruitleads totoxicity
β-blockers:leads to HF, AV block, bradycardia
Antidysrhythmics
(Class III: K+-Channel Blockers)
Expected Action:
decreased conduction / decreased automaticity / decreased repolarization rate / decreased contractility
Potassium channel blockers: amiodarone (Cordarone), bretylium, sotalol, dofetilide
Therapeutic Uses:
Conversion of A-fib (oral)
Recurrent V-fib
Recurrent V-tach
Adverse Effects:
Pulmonary toxicity
Visual disturbances (can leads to blind)
Cardiac effects leads to sinus bradycardia & AV block / may cause HF / Hypotension
Liver/thyroid dysfunction
CNS effects
GI effects
Phlebitis: Central venous line is indicated
Contraindications/Precautions:
Pregnancy (D)
CI: AV block, bradycardia, newborns, infants
Interactions:
Grapefruit leads to toxicity
Cholestyramine leads to decreased [amiodarone]
Quinidine, procainamide, digoxin, diltiazem, warfarin leads to increased levels of these
β-blockers, verapamil, diltiazem leads to bradycardia
Diuretics, antidysrhythmics, macrolide antibiotics leads to increased risk dysrhythmias
Antidysrhythmics
(Endogenous Glucoside)
Expected Action:
decreased conduction through AV node
Endogenous Glucoside: adenosine (Adenocard), ibutilide (Corvert)
Therapeutic Uses:
Paroxysmal SVT, Wolff-Parkinson Syndrome
Adverse Effects:
Sinus bradycardia, dyspnea, flushed face (usually < 1 min)
Contraindications/Precautions:
Pregnancy (C)
CI: 2/3º block, AV block, atrial flutter, atrial fibrillation
Interactions:
Methylxanthines (theophylline, caffeine) leads to Adenosine receptors are blocked
Dipyridamole (Persantine) leads to Uptake is blocked leading to increased effects
Education:
Very short life (< 1 min)
Administer by IV bolus, flushed with NS
Antilipemics
HMG CoA Reductase Inhibitors
(Statins)
Expected Action:
decreased LDL by increased LDL receptors in liver
decreased VLDL, increased HDL
Promote vasodilation / decreased plaque-site inflammation / decreased thromboembolism risk
Therapeutic Uses:
1º hypercholesterolemia
increased HDL
Prevention of stroke and coronary events.
Adverse Effects:
Myopathy (monitor CK), Peripheral neuropathy, Hepatotoxicity evidenced by increased serum transaminase
Contraindications/Precautions:
Pregnancy (X)
V rosuvastatin in Asians
CI: Pregnant / viral or EtOH hepatitis
Caution ĉ ketoconazole
Interactions:
Fibrates leads to increased risk of myopathy
Med that suppress CYP3A4 (ketoconazole, erythromycin) leads to increased statin levels
Grapefruit juice and (lovastatin or simvastatin) leads to Toxicity
Education:
Lovastatin ĉ evening meal (others OK ŝ food)
Atorvastatin or fluvastatin should be used with renal insufficiency
Antilipemics – Fibrates
Expected Action:
decreased TG by increased VLDL excretion
Promote HDL precursor production
Examples: gemfibrozil (Lopid) — Others: fenofibrate (Tricor
Therapeutic Uses:
decreased plasma VLDL, increased plasma HDL
Adverse Effects:
Gall stones, Hepatotoxicity, Myopathy
Contraindications/Precautions:
Pregnancy (C), Caution ĉ statins, CI: liver disorders / severe renal dysfunction / gallbladder disease
Interactions:
Statins leads to increased myopathy
Cholestyramine leads to decreased absorption
Warfarin leads to increased risk of bleeding (monitor PT and INR)
Antilipemics – Cholesterol
Absorption Inhibitor
Expected Action:
Inhibit absorption of cholesterol secreted in the bile and from food.
Example: ezetimibe (Zetia)
Therapeutic Uses:
Adjunct to modified diet to help decreased LDL (alone or ĉ statin)
Adverse Effects: Well-tolerated – no adverse effects
Contraindications/Precautions:
Pregnancy (X)
Caution ĉ breastfeeding
CI: Renal dysfunction
Interactions:
Bile acid sequestrants (cholestyramine) decreased absorption
Use with fibrates (gemfibrozil) leads to increased risk of gall stones and myopathy
Cyclosporine leads to increased levels of ezetimibe
Education:
Taken once per day without regard to food
Antilipemics
Bile-Acid Sequestrants
Expected Action:
increased LDL receptors in liver promotes uptake of serum cholesterol leads to decreased LDL
Example: cholestyramine (Questran) — Others: colestipol (Colestid)
Therapeutic Uses:
Adjunct with HMG CoA reductase inhibitor (eg atorvastatin) & diet leads to LDL
Adverse Effects:
No systemic effects (not absorbed in GI tract)
Constipation
Contraindications/Precautions:
CI: biliary disease or increased VLDL
Interactions:
Digoxin, warfarin, thiazides, tetracyclines leads to form complexes decreased absorption
Education:
Dissolve in water or applesauce to prevent esophageal irritation or impaction.
