Correct!
2. Magnesium sulfate
The rhythm is torsades de pointes, or torsades, an uncommon and distinctive form of polymorphic ventricular tachycardia (VT) characterized by a gradual change in the amplitude and twisting of the QRS complexes around the isoelectric line (2). Torsades is associated with a prolonged QT interval, usually terminates spontaneously but frequently recurs and may degenerate into ventricular fibrillation.
The etiology and management of torsades are different from those of usual ventricular tachycardia. Magnesium is the drug of choice in torsades. Magnesium achieves this by decreasing the influx of calcium. Group IA antiarrythmics such as procainamide and quinidine tend to prolong the QT interval, and can worsen torsades. Differentiating between these entities, therefore, is critically important. Lidocaine is usually without effect in torsades.
Intravenous access was established and magnesium 4 gm was administered. She was defibrillated a total of 3 times. Throughout the resuscitative efforts she had respiratory effort, and she was assisted with bag valve mask. Return of spontaneous circulation was achieved after 10-12 minutes of CPR.
Which of the following are associated with torsades? (Click on the correct answer to proceed to the third of four panels)