Anti-Dysrythmic Poisoning

Question 1

What anti-dysrythmics can cause toxicity?

Answer 1

• Flecainide, lidocaine, procainamide, quinidine
• These drugs alter cardiac rhythms making toxicity highly lethal.
• Patients have an underlying rhythm disorder already, making them more susceptible to the effects of toxicity.

Question 2

What are the subjective/physical exam findings associated with anti-dysrythmic medications?

Answer 2

Subjective/physical findings are broad and include N/V/D, dizziness, blurred vision, bradycardia, hypotension, CV collapse, delirium, seizures, coma

Question 3

What lab/diagnostic tests are done for patients with anti-dysrythmic toxicity?

Answer 3

• A serum level of the suspected medication should be drawn ASAP to confirm overdose and serve as a baseline.
  
  • It is the most important diagnostic tool.
• EKG findings: Bradycardia with AVB, Torsade de pointes. Basic screening lab may show findings consistent with leukopenia, thrombocytopenia, hemolytic anemia, hepatotoxicity

Question 4

How do you manage a patient with an anti-dysrythmic toxicity?

Answer 4

• 12 lead EKG and continuous monitoring
• Charcoal administration PO/NG.
• If the patient is bradycardic, give atropine 1 mg IV (can repeat every 5 minutes).
  
  • If ineffective, can use isoproterenol 2 mg/250 ml continuous infusion and titrate to maintain heart rate greater than 60 bpm