What are the contraindications for a Cardizem (Diltiazem) drip?

Contraindications for Cardizem (Diltiazem) Drip

Cardizem (diltiazem) drip is absolutely contraindicated in patients with sick sinus syndrome, second or third-degree AV block (without a functioning ventricular pacemaker), severe hypotension, cardiogenic shock, decompensated heart failure, severe left ventricular dysfunction, and ventricular tachycardia.

Absolute Contraindications

• Cardiac Conduction Abnormalities:

  • Sick sinus syndrome (without a functioning ventricular pacemaker) 1
  • Second or third-degree AV block (without a functioning ventricular pacemaker) 1
  • Pre-excitation syndromes (WPW syndrome with atrial fibrillation/flutter) 2, 1

• Hemodynamic Instability:

  • Severe hypotension 1
  • Cardiogenic shock 1

• Cardiac Function Issues:

  • Decompensated heart failure 2
  • Severe left ventricular dysfunction 2, 3

• Arrhythmias:

  • Ventricular tachycardia 1
  • Wide complex tachycardia of uncertain origin 1

• Other:

  • Known hypersensitivity to diltiazem 1
  • Concomitant IV beta-blocker administration 1

Relative Contraindications/Use with Caution

• Medication Interactions:

  • Concomitant oral beta-blocker therapy (increased risk of bradycardia, heart block) 4, 5
  • Multiple CYP3A4 substrate/inhibitor interactions 2

• Patient Conditions:

  • Renal dysfunction (increased risk of toxicity) 6
  • Hepatic dysfunction
  • Elderly patients (increased sensitivity to hypotensive effects) 3, 7
  • Bradycardia 3
  • First-degree AV block 2

Clinical Considerations

Monitoring Requirements

When administering diltiazem drip, careful monitoring is essential for:

• Blood pressure (risk of hypotension) 7
• Heart rate (risk of bradycardia) 3
• ECG (for conduction abnormalities) 4
• Signs of worsening heart failure 3

Management of Adverse Effects

• Hypotension: Avoid fluid boluses in patients with heart failure 3
• Bradycardia/heart block: Calcium chloride (1-2g IV) may reverse calcium channel blocker toxicity 6
• Continuous cardiac monitoring is mandatory during administration 3

Alternative Agents

For patients with contraindications to diltiazem:

• In preserved LV function: Beta-blockers (metoprolol, esmolol) 3
• In reduced LV function: Amiodarone or digoxin 3

Special Populations

Heart Failure Patients

Diltiazem can worsen heart failure in patients with pre-existing ventricular dysfunction 2. For these patients, alternative rate control agents should be considered.

Elderly Patients

Lower initial doses are recommended due to increased risk of orthostatic hypotension and conduction abnormalities 3, 6.

The decision to use diltiazem drip requires careful assessment of the patient's cardiac function, conduction system, hemodynamic status, and concurrent medications to minimize risks of serious adverse effects.