How to Administer a Cardizem (Diltiazem) Push
For rapid control of ventricular rate in atrial fibrillation/flutter or conversion of PSVT, administer intravenous diltiazem at a dose of 0.25 mg/kg (approximately 15-20 mg for an average adult) over 2 minutes, followed by continuous monitoring. 1, 2
Preparation and Administration
- Ensure IV access is patent and functioning properly 2
- Calculate the dose based on patient weight (0.25 mg/kg) 1
- Draw up the calculated dose of diltiazem from the vial 2
- Administer the dose slowly over 2 minutes via IV push 3, 1
- Have resuscitation equipment readily available during administration 1, 2
Monitoring During Administration
- Continuous ECG monitoring is essential throughout administration 2
- Frequent blood pressure measurements should be taken before, during, and after administration 2
- Monitor for hypotension, which is the most common adverse effect 4, 1
- Watch for bradycardia and potential worsening of heart failure in predisposed patients 1
Dosing Considerations
- Standard initial dose: 0.25 mg/kg IV over 2 minutes (approximately 15-20 mg for average adult) 1, 2
- Some evidence suggests lower doses (≤0.2 mg/kg) may be equally effective with reduced risk of hypotension 5
- For patients with atrial fibrillation/flutter, response usually occurs within 3 minutes with maximal heart rate reduction in 2-7 minutes 2
- For PSVT, conversion to normal sinus rhythm typically occurs within 3 minutes of the first or second bolus dose 2
Follow-up Dosing
- If inadequate response to initial dose, a second dose of 0.35 mg/kg may be given after 15 minutes 1
- After successful rate control with IV bolus, consider continuous infusion at 5-15 mg/hour if needed 6
- For transition to oral therapy, initiate oral diltiazem 4 hours before discontinuing IV infusion 6
Contraindications and Cautions
- Avoid in patients with pre-excited atrial fibrillation or flutter (WPW syndrome) 1, 2
- Do not use in patients with AV block greater than first degree or significant SA node dysfunction 1
- Use with caution in patients with heart failure or impaired ventricular function 1
- Avoid in patients with hypotension (systolic BP <90 mmHg) 1
- Use caution when administering with other drugs that decrease peripheral resistance, myocardial filling, contractility, or electrical impulse propagation 2
Management of Adverse Effects
- For hypotension: Place patient in Trendelenburg position and administer IV fluids 2
- For severe bradycardia: Consider atropine or temporary pacing if needed 3
- For worsening heart failure: Discontinue diltiazem and provide appropriate supportive care 1
Clinical Pearls
- Heart rate reduction may last from 1-3 hours after bolus administration 2
- Hypotension, if it occurs, is generally short-lived but may last from 1-3 hours 2
- Diltiazem rarely converts atrial fibrillation/flutter to normal sinus rhythm but is highly effective for rate control 2
- For PSVT, diltiazem has shown 88% effectiveness in converting to normal sinus rhythm 2