Torsades de pointes: Difference between revisions

m (Rossdonaldson1 moved page Torsades De Pointes to Torsades de pointes)
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Increasing HR decreases QT interval
Increasing HR decreases QT interval
#Magnesium - decreases calcium influx
#Magnesium - decreases calcium influx
##1-2gm IV over 1-2 min, repeat in 5-15min; then 1-2gm/hr (3-10mg/min) gtt
#*1-2gm IV over 1-2 min, repeat in 5-15min; then 1-2gm/hr (3-10mg/min) gtt
###Danger of hyperMag2+ → depressed neuromuscular function, so monitor closely
#**Danger of hyperMag2+ → depressed neuromuscular function, so monitor closely
###Supplement with K+
#**Supplement with K+
#Isoproterenol - Increases HR / AV conduction
#Isoproterenol - Increases HR / AV conduction
##2-8 mcg/min
#*2-8 mcg/min
#[[Overdrive Pacing]] - Atrial > Ventricular pacing
#[[Overdrive Pacing]] - Atrial > Ventricular pacing
##Goal HR 90-120
#*Goal HR 90-120
#Defibrillation / Synchronized Cardioversion - Pt in extremis
#Defibrillation / Synchronized Cardioversion - Patient in extremis


==See Also==
==See Also==

Revision as of 06:25, 25 February 2015

Background

  • Torsades de Pointes is a form of polymorphic VTach, where there is a gradual change in the amplitude and twisting of the QRS complexes around the isoelectric line
  • Associated with prolonged QT, which may be congenital or acquired. POINTES mnemonic for common etiologies:
    • Phenothiazines
    • Other medications (ie TCAs)
    • Intracranial bleed
    • No known cause (idiopathic)
    • Type I anti-arrhythmics (quinidine, procainamide, disopyramide)
    • Electrolyte abnormalities (hypoK & hypoMag)
    • Syndrome of Prolonged QT (aka Long QT Syndrome)

Treatment

Increasing HR decreases QT interval

  1. Magnesium - decreases calcium influx
    • 1-2gm IV over 1-2 min, repeat in 5-15min; then 1-2gm/hr (3-10mg/min) gtt
      • Danger of hyperMag2+ → depressed neuromuscular function, so monitor closely
      • Supplement with K+
  2. Isoproterenol - Increases HR / AV conduction
    • 2-8 mcg/min
  3. Overdrive Pacing - Atrial > Ventricular pacing
    • Goal HR 90-120
  4. Defibrillation / Synchronized Cardioversion - Patient in extremis

See Also

Source

  • Tintinalli