Magnesium Sulfate

Question 1

Classification

Answer 1

Anticonvulsant, antidysrhythmic, electrolyte, tocolytic, mineral

Question 2

Mechanism of Action

Answer 2

• Required for normal physiologic function
• Cofactor in neurochemical transmission & muscular excitability
• Controls seizures by blocking peripheral neuromuscular transmission
• Peripheral vasodilator
• Inhibits platelet function

Question 3

Indications

Answer 3

• Torsades de pointes
• Cardiac arrythmias associated with hypomagnesemia
• Eclampsia
• Seizure prophylaxis in pre-eclampsia
• Status asthmaticus

Question 4

Contraindications

Answer 4

• AV Block
• GI obstruction

Question 5

Adverse Effects

Answer 5

• Cardiovascular depression/collapse
• Respiratory paralysis
• Hypothermia
• Pulmonary edema

Question 6

Administration

Answer 6

• Pulseless VF/VT with Torsades de Pointes or Hypomagnesemia
  
  • ​Adult: 1-2 g in 10 mL D5w IV/IO over 5-10 minutes
  • Peds: 25-50 mg/kg IV/IO over 10-20 minutes, max 2 g
• Pulsed Torsades or arrythmias with Hypomagnesemia
  
  • ​Adult: 1-2 g in 50-100 mL D5w IV/IO over 5-60 minutes, follow with 0.5-1 g/hr IV/IO, titrate to control torsades de pointes
  • Peds: 25-50 mg/kg IV/IO over 10-20 minutes, max 2 g
• Eclampsia & Seizure Prophylaxis in Preeclampsia
  
  • ​4-6 g IV/IO over 20-30 minutes, followed by an infusion of 1-2 g/hr
• Status Asthmaticus
  
  • ​Adult: 1.2-2 g slow IV/IO over 20 minutes
  • Peds: 25-50 mg/kg (diluted in D5W) slow IV/IO over 10-20 minutes