Eclamptic seizure, torsades de pointes, arrest secondary to hypomagnesemia..
Nausea, vomiting, cramps, anorexia; smooth muscle relaxation.
Potentially Lethal Side Effects:
flaccidity, paralysis, circulatory collapse.
Use without indication.
Torsades de pointes (ACLS):
Loading: IV loading infusion: 1-2g in 50-100ml D5W** over 5-60 minutes, as determined by clinical presentation.
Maintenence infusion: 0.5-1g/hr for up to 24 hours
Eclamptic Seizure*:
IV Push: 20% MgSO4: 2-4g. @ <1g/min, titrated to cessation of seizure
Infusion: 1-4g/hr
Max dose is 4g.
PALS Pulseless Arrest: Suspected Torsades or Hypomagnesemia
IV/IO Infusion: 25-50mg/kg/10-20 min, to max 2g
Adult:
For 20ml of 20% Magnesium Sulfate solution:
(a) Mix 8ml of 50% solution with 12ml NaCl to yield 20ml of 20% solution (i.e.: 1g/5ml)
OR
(b) Add 5g to 250ml (i.e.: 1g/50ml) NaCl.
Given 60gtt/ml set:
50gtt/min=1g/hr. 100gtt/min=2g/hr. 150gtt/min=3g/hr. and 200gtt/min=4g/hr.
Pediatric:
Add 2g to 50ml NaCl
Given 60gtt/ml set:
60gtt/min=240mg/min; 30gtt/min=120mg/min; 15gtt/min=60gtt/min
* Local protocols vary. See local protocols.
** ACLS recommends reconstitution of vial MgSO4 into D5W, which can be prepared by pre-mixing D50 into 0.9% NaCl.in systems where D5W is not carried in the prehospital setting..
- When max dosing has been administered, local protocols may refer to Seizure protocol for further treatment.
- Discontinue use of Magnesium Sulfate if pt. experiences: loss of deep tendon reflexes, respiratory depression/arrest, CNS depression, flaccid paralysis, severe bradycardia/hypotension, widened QRS complex, cardiac arrest. Calcium Chloride is used as an antagonist in the event of Magnesium overdose.