Antidysrhythmics

1. action

• 1. prevent abnormal heart rhythms
• 2. action depends on type of antidysrhythmics drug

2. examples

• 1. class I: sodium channel blockers - quinidine (Quinidex), lidocaine; decreases myocardial excitability and contractility
• 2. class II: beta blockers -propranolol (Inderal); stabilizes cell membrane
• 3. class III: conduction delayers- bretylium (Bretylol); decreases conduction and excitability of myocardial cells
• 4. class IV: calcium channel blockers - verapamil (Isoptin);inhibits influx of calcium ions across cell membrane during cardiac contraction; reduces cardiac excitability and dilates main coronary arteries
• 5. others - digoxin (Lanoxin), adenosine (Adenocard); slows heart rate, improves pumping ability of the heart

3. use: to treat abnormalities in cardiac rate and rhythm

4. adverse effects

• 1. hypotension
• 2. nausea and vomiting
• 3. blood dyscrasias
• 4. toxicity such as CNS disturbances due to neurotoxicity, and diarrhea due to GI irritation

5. nursing interventions
1. monitor cardiac rhythm
2. monitor blood levels
3. monitor for blood dyscrasias
4. administer oral preparations with meals
5. monitor EKGs
6. use infusion-control devices for IV administration
7. teach client
* report changes in heart rate and/or rhythm
report any side effects