Treatment for torsades de pointes
Torsades de pointes can be life threatening. First-line treatment for drug-induced torsades de pointes is magnesium sulfate. Use:
magnesium sulfate 50% 4 mL (8 mmol) (child: 0.1 mL/kg up to 4 mL [0.2 mmol/kg up to 8 mmol]) intravenously, over 10 to 15 minutes resuscitation for poisonings - torsades de pointes
FOLLOWED BY if required
magnesium sulfate 50% 1 to 1.5 mL/hour (2 to 3 mmol/hour) (child: 0.06 mL/kg/hour [0.12 mmol/kg/hour]) by intravenous infusion for 12 to 24 hours.
For patients with prolonged QT interval and torsades de pointes, ensure their heart rate is maintained above 90 beats per minute. If required, the most commonly used chronotropic drug is intravenous isoprenaline. If the patient’s heart rate is less than 90 beats per minute, an intravenous bolus regimen of isoprenaline is usually started to assess heart rate response. Use:
isoprenaline 20 micrograms (child: 0.1 micrograms/kg) intravenously, every 2 to 3 minutes, aiming for a heart rate above 90 beats per minute. resuscitation for poisonings - torsades de pointes
Assess haemodynamic response and switch to an isoprenaline infusion when practical. For adults and children, use:
isoprenaline by intravenous infusion (see Isoprenaline intravenous infusion instructions for advice on preparation and administration).
Alternatives to isoprenaline include transcutaneous or transvenous pacing, or other drugs, including adrenaline or atropine.
If torsades de pointes deteriorates to sustained ventricular tachycardia or ventricular fibrillation (cardiac arrest), follow advanced life support protocols1.