Problems for Discussion - 2 - Cardiac glycosides

A 20-month-old female weighing 12 kg presents to the emergency department 90 minutes after being found with her grandfather’s digoxin 250 mcg tablets. A count of the tablets reveals that up to 6 may be missing. The child appears well.

1. What is your risk assessment? What symptoms and signs would you anticipate if this dose has been ingested?
2. Would you perform gastrointestinal decontamination on this child? If so, what would you do?
3. Is immediate treatment indicated?
4. How long would you observe the child in the emergency department?

You are consulted by a doctor in a rural emergency department. A 48-year-old male has presented two hours after deliberately ingesting 120 tablets of digoxin 125 mcg. He is nauseated, feels dizzy and has vomited once. Examination reveals a pulse of 72 bpm and blood pressure of 135/ 85 mmHg. The 12-lead ECG is normal apart from two ventricular ectopic beats on the rhythm strip.

1. What is your risk assessment?
2. What gastrointestinal decontamination might be appropriate?
3. What criteria may be used to determine when digoxin-specific antibodies are indicated in this clinical setting?
4. The rural hospital does not stock digoxin-specific antibodies. What dose of digoxin-specific antibodies should be taken with the aeromedical retrieval team?

An 80-year-old female who is usually independent presents with a 10-day history of increasing lethargy, anorexia and confusion. She takes digoxin 62.5 mcg daily and her GP commenced a thiazide diuretic three weeks ago. She collapsed and vomited on the day of presentation. She appears weak and dehydrated. Her heart rate is 48 and irregular and her blood pressure is 95/55 mmHg. Her 12-lead ECG shows slow atrial fibrillation and frequent ventricular ectopic beats. Her serum creatinine is 158 mcmol/L and her serum potassium is 4.4 mmol/L. Her serum digoxin level is 3.1 nmol/L (2.4 ng/mL).

1. What is your risk assessment?
2. What are the indications for digoxin-specific antibodies in chronic digoxin intoxication?
3. Are digoxin-specific antibodies indicated in this case?
4. How would you calculate the dose?
5. What would be her disposition?