torsade is an inherently unstable rhythm and will either revert or degenerate to VF, thus commence Rx as soon as it is recognised.
Most (75-82%) torsade de pointes (TDP) rhythms are started by a pause. Pacing at rates up to 140 bpm may prevent the ventricular pauses that allow TDP to originate.
often associated with prolonged QTc on ECG which may be hereditary, drug-induced, or have other causes.
a rare cause is Brugada syndrome which if untreated may be fatal within 2 years.
Mx of torsade de pointes VT:
oxygen, cardiac monitor, IV access, move to full resuscitative facilities and procedures as for VT
usually very effective even in patients with normal Mg levels
if fails, repeat dose but watch for Mg toxicity including impaired NM function
consider:
overdrive pacing to HR of 140
iv isoprenaline (isoproterenol) infusion to maintain HR of 90-100bpm to prevent recurrence
short-acting beta blockers such as iv esmolol can be tried in patients with congenital prolonged QT syndrome but should NOT be used in cocaine-induced cases.