Overview
Torsades de pointe (TdP) is a specific form of polymorphic ventricular tachycardia often induced by drug toxicity, particularly affecting the QT interval on the electrocardiogram. In the context of atypical antipsychotic overdose, quetiapine has been implicated in causing severe hemodynamic instability, including TdP 1.Diagnosis
Electrocardiogram (ECG) showing prolonged QT interval and characteristic twisting of the QRS complexes 1.
Clinical presentation may include syncope, seizures, or sudden hemodynamic collapse 1.
Toxicology screen confirming quetiapine levels can aid in diagnosis 1.Management
First-line treatment: Fluid resuscitation and monitoring of electrolytes, particularly potassium and magnesium levels 1.
Adjunctive treatments: Avoid adrenaline due to potential paradoxical hypotension; consider noradrenaline for hemodynamic support 1.
Specific interventions: Consider magnesium sulfate (2-4 grams IV over 1-2 minutes) if TdP is suspected 1.Special Populations
No specific data provided for pregnancy, pediatrics, elderly, or comorbidities in the given abstracts 1.Key Recommendations
Use noradrenaline instead of adrenaline for managing shock in patients with quetiapine overdose to prevent paradoxical hypotension (Evidence: Weak) 1.
Administer magnesium sulfate if TdP is suspected in quetiapine overdose cases (Evidence: Weak) 1.
Monitor and correct electrolyte imbalances, especially potassium and magnesium, in patients with quetiapine toxicity (Evidence: Expert opinion) 1.References
1 Hawkins DJ, Unwin P. Paradoxical and severe hypotension in response to adrenaline infusions in massive quetiapine overdose. Critical care and resuscitation : journal of the Australasian Academy of Critical Care Medicine 2008. link