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Tricyclic antidepressant toxicity — RCPSC EM MCQ

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HardToxicologyTricyclic antidepressant toxicityRCPSC EM

CTAS 1: A 34-year-old is brought in after ingesting unknown tablets. Vitals are BP 86/48, HR 148, RR 10, GCS 8. ECG shows QRS 164 ms with terminal R in aVR; VBG shows pH 7.21 and lactate 4.8 mmol/L. Seizure activity stops after midazolam. What is the most appropriate initial management?

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Correct answer: B — Intravenous sodium bicarbonate boluses

Wide QRS, hypotension and seizures after TCA ingestion require sodium bicarbonate to narrow the QRS and improve haemodynamics. Airway protection and poison centre consultation follow in parallel.

Reference: ACMT toxicology guidance; Canadian Poison Centre resources