Aconite poisoning presenting as hypotension and bradycardia

Abstract

The principal toxic ingredients of aconite roots include aconitine, mesaconitine and hypaconitine, which are known cardiotoxins and neurotoxins. A 58-year-old man took a decoction of 11 g each of processed ‘chuanwu’ (the main root of Aconitum carmichaeli) and processed ‘caowu’ (the root of A. kusnezoffii) as treatment for his neck pain. One hour later, he experienced numbness of tongue and the four limbs, generalized weakness, nausea, vomiting, diarrhoea and dizziness. Three hours after ingestion, he was admitted to hospital. His blood pressure was 106/53 mmHg and heart rate 65 beats/min. Six hours after ingestion, he became hypotensive (systolic blood pressure <100 mmHg) with bradycardia (heart rate <60 beats/min). As treatments for the hypotension, he was given intravenous infusions of 0.9% saline (125 mL/hour) for 15 hours (7-21 hours after ingestion) and dopamine (3 μg/kg/min) for 36 hours (10-45 hours after ingestion). He was given atropine 0.6 mg intravenously 7 and 24 hours after ingestion. He was hypotensive for 31 hours (6-36 hours after ingestion), with a systolic blood pressure of 84-106 mmHg (mean 93.5) and a diastolic blood pressure of 40-59 mmHg (mean 51.8). He had bradycardia for 36 hours (6-41 hours after ingestion), with a heart rate of 45-68 beats/min (mean 56.5). On discharge (48 hours after ingestion), his blood pressure was 117/82 mmHg and heart rate 70 beats/min. In patients with aconite poisoning, prolonged hypotension and sinus bradycardia may occur and supportive therapy with close monitoring of blood pressure and cardiac rhythm are essential.