A 38 yr old male presents to your emergency department 2 hours after ingesting an unknown quantity of amitriptyline (TCA) with a GCS of 13, HR 130, BP96/50, Temp 35.6, Sats of 100%. His ECG shows a QRS of 160ms, you give 3 amps of sodium bicarbonate and his QRS is still 160ms. What now?
Dr Emily Austin a toxicologist from Toronto talks us through the case and gives us some additional options.
Management options for sodium channel blocker overdose:
- Whatever treatment you give, bear in mind the 3 end goals:
- Narrowing the QRS to normal for the patient or less than 100ms
- Maximum Sodium of 155 mmol/L
- pH between 7.5 – 7.55
- Sodium bicarbonate 8.4% boluses (monitor potassium, pH and sodium levels)
- Intubate and hyperventilate to a pH of 7.5 to 7.55
- 3% saline can be given to achieve a sodium of 155 mmol/L if further bicarbonate can not be given.
- Lidocaine 1-1.5mg/kg slow IV push, followed by 20-50 ug/kg/min infusion
LITFL TCA post for a deeper dive:
- TCA Toxicity overview
- ECG Library – Tricyclic Overdose
- Tox Conundrum 022 – Tricyclic antidepressant toxicity
- Tox Conundrum 050 – Another TCA overdose!
DRUGS and TOXICANTS