Role of magnesium in torsades de pointes during arrest?

• A. Magnesium sulfate 1-2 g IV push; may repeat if torsades persists
• B. No role
• C. Magnesium 10 g IV
• D. Oral magnesium

Answer: (A)

Torsades de pointes during arrest is treated with magnesium sulfate because it helps stabilize the cardiac membrane and suppress the early afterdepolarizations that drive this rhythm, even if magnesium levels are normal. In the pulseless setting, give 1–2 grams of magnesium sulfate IV push (over 1–2 minutes) and you may repeat once if torsades persists. If the rhythm keeps recurring, start a continuous infusion of 0.5–1 gram per hour for ongoing control. Oral magnesium is not suitable in arrest due to delayed, unreliable absorption and lack of rapid effect, and a very large IV dose like 10 grams is not the standard initial approach.