A normally well 19-year-old female (65 kg) is admitted to your ICU after she had an intentional ingestion of 50 tablets of (her mother's) verapamil 180 mg (sustained release). The ingestion was 4 hours ago.
On admission, she is conscious, feels lightheaded, and has a heart rate of 40 beats/minute and a blood pressure of 90/40 mmHg.
Describe your management. Include in your answer how she is likely to deteriorate, and what general and specific therapies you would employ as her condition worsens.
This is a significant overdose of a non-dihydropyridine CCB, which would result in both vasodilatation and decreased inotropy/chronotropy. She already has symptomatic hypotension and bradycardia, which is likely to deteriorate and be prolonged due to the sustained release preparation ingested.
Immediate resuscitation –
Early contact with Poisons Information Centre (or equivalent) for advice.
Lipid “sink” therapy
Specific therapies - Simultaneous rather than stepwise therapy in this case given severity of CCB poisoning.
Marks were allocated more for specific management strategies than general resuscitation. Drug doses were not required.
Mention of Lipid Sink therapy essential to score greater than 4 marks
Expected pattern of deterioration
General supportive management
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