Mag, Mag Sulfate, MgSO4, Mg++

Question 1

Mag Sulfate Class

Answer 1

• Antidysrhythmic
• Anticonvulsant
• CNS Depressant

Question 2

Mag Sulfate Action

Answer 2

• Anticonvulsant properties—reduces striated muscle contractions and blocks peripheral neuromuscular transmission by reducing acetylcholine release at the myoneural junction
• Antidysrhythmic properties—Physiological CCB. Reduces SA node impulse formation, prolongs conduction time in myocardium.

Question 3

Mag Sulfate Indications

Answer 3

• Refractory VF, VT (with or without a pulse) (if hypomagnesemia is suspected)
• Refractory ventricular ectopy (if hypomagnesemia is suspected)
• TDP (treatment of choice)
• Seizure prevention and control in preeclampsia and eclampsia (treatment of choice)
• Suspected hypomagnesemia
• Status asthmaticus not responsive to β agonists or anticholinergics.
• Cardiac Arrest only if Torsades De Pointe is present

Question 4

Mag Sulfate Contraindications

Answer 4

• Heart block
• MI
• Hypermagnesemia

Question 5

Mag Sulfate Precautions

Answer 5

Renal insufficiency

Question 6

Mag Sulfate Dosage

Answer 6

Adults:
• Preeclampsia:
IV/IO: 4 g over 20 minutes, repeat PRN. Do not give faster than 1 g/minute. To Mix: 4 g /250 ml using a 15 gtt set. Run at equivalent of 750 ml/hour. Titrate for effect. Max 8g. If seizures occur, run at eclampsia dosing. Maintenance Infusion: 5 g/250ml NS, run at 100 ml/hr (2 g/hr)
• Eclampsia (active seizures):
IV/IO: 4 g over 5 minutes, repeat PRN. Do not give faster than 1 g/minute. To Mix: 4 g /250 ml using a 15 gtt set. Run at equivalent of 3000 ml/hour. Titrate for effect. Max 8g. Maintenance Infusion: 5 g/250ml NS, run at 100 ml/hr (2 g/hr)
• Refractory Broncheospasm:
IV/IO: 2 g over 5 minutes, repeat PRN. Do not give faster than 1 g/minute. To Mix: 2 g /250 ml using a 15 gtt set. Run at equivalent of 3000 ml/hour. Titrate for effect. Max 4g.
• Refractory VT, VF, TDP:
IV/IO: 2 g q 5 minutes, 1st line for Torsades or refractory
V-Fib/Pulseless V-Tach. To Mix: 2 g (4ml), dilute to a
total of 20 ml to make 10% solution. Do not give faster than 1g/minute.
Pediatrics:
Refractory VT, VF, TDP, Refractory Bronchospasm — IV/IO: 25-50 mg/kg in 100 ml Buretrol over 2-5 minutes, MAX 2g

Question 7

Mag Sulfate Onset/ Duration

Answer 7

• Onset: IV—Immediate. IM–3-4 hours

* Duration: IV—30-60 min. IM–3-4 hours

Question 8

Mag Sulfate Side Effects

Answer 8

• Flushing/Sweating
• Itching/Rash
• Hypothermia
• Drowsiness
• Respiratory depression
• Respiratory failure
• Bradycardia/AV block
• Cardiac arrest
• Circulatory collapse
• Complete heart block
• Flaccid paralysis
• Absence of knee jerk
• Hypotension, Diaphoresis

Question 9

Mag Sulfate Interactions

Answer 9

• Incompatible–alcohol, salicylates, sodium bicarbonate
• Additive effects can occur with other CNS depressants
• Concurrent use with nifedepine in the treatment of maternal hypertension can cause increased hypotension or pronounced muscle weakness and may harm the fetus
• Can cause cardiac conduction abnormalities when used in conjunction with cardiac glycosides