Seizures in labor

Question 1

Dose of Mag in labor

Answer 1

6g IV bolus over 15min followed by maintenance of 2g IV/hr. If renal insufficiency, could do 6g bolus and then 1g/hr. Renal insufficiency is Cr >1.1

Question 2

Dose of IM mag if no IV access?

Answer 2

5g IM in each butt cheek. Then 5g every 4 hours.

Question 3

How do you manage repetitive seizures?

Answer 3

can do 2-4g bolus over 5 min. Also give ativan. Most pts recover responsiveness in 5-10 min. If not, then sodium barbitol and start phenytoin.

If Mag not responsive, get head imaging to make sure there’s not another cause.

Question 4

How do you prevent Mag toxicity?

Answer 4

• Place Foley to monitor renal function (hourly output)
• Confirm normal serum creatinine
• Serial evaluation of patellar deep tendon reflexes
• Monitor respiratory rate
• Serum magnesium levels not routinely required
• Monitor serum magnesium levels in setting of renal dysfunction and/or absence of patellar reflexes
• Maintain serum concentrations 5 to 9 mg/dL (4–7 mEq/L) range
  Predictive symptoms of magnesium sulfate toxicity
  
  • Loss of deep tendon reflexes >9 mg/dL (greater than 7 mEq/L)
  • Respiratory depression >12 mg/dL (greater than 10 mEq/L)
  • Cardiac arrest >30 mg/dL (greater than 25 mEq/L)

Question 5

Initial management of seizures in labor?

Answer 5

• call for help
• assess ABC
• Place patient in lateral decubitus position
• suction mouth
• place oxygen facemask
• check VS, pulse Ox.
• if seizure doesn’t resolve in 5 min, give benzodiazepine (lorazepam 4mg IV over 2min)
• can have post-octal state for 10-15 min.

Can have FHR decelerations. If >15 min despite resuscitation, consider abruption and proceed with c-section.

Question 6

What is reversal agent for magnesium sulfate?

Answer 6

Calcium gluconate. 1g/2 min IV. to avoid hypotension and/or bradycardia

Question 7

What conditions are contraindications to magnesium therapy?

Answer 7

Myasthenia gravis
Hypocalcemia
Moderate-to-severe renal failure
Cardiac ischemia
Heart block
Myocarditis

Question 8

What is fetal hydantoin syndrome?

Answer 8

a characteristic pattern of mental and physical birth defects that results from maternal use of the anti-seizure (anticonvulsant) drug phenytoin (Dilantin) during pregnancy

Causes growth restriction, VSD, ASD, cleft lip, dysmorphic facial features.

Question 9

What is consideration after seizure?

Answer 9

if no return to consciousness, consider
- Mag toxicity (need 1g calcium gluconate)
- CVA event (neuro consult and neuron-imaging)

Fetal monitoring
- bradycardia for 3-5 min common.