Magnesium Sulfate for Protection Against Cerebral Palsy and Motor Dysfunction

Cerebral Palsy and Birth Injury Lawyer Discusses a Treatment (Magnesium Sulfate) that Can Help Prevent Brain Injury from a Lack of Oxygen at Birth

Cerebral palsy is a term used to describe a group of disorders of movement and / or posture that do not change in character.  It is the most common cause of severe motor disability in childhood.

Prematurity is a risk factor for cerebral palsy, and the number of children at risk for cerebral palsy is increasing.
RESEARCH SUPPORTS MAGNESIUM SULFATE’S NEUROPROTECTIVE EFFECTS

In the 1990s it was proposed that exposure to magnesium sulfate in the womb has a neuroprotective effect on the baby.  A Cochrane review completed just a few years ago supports this; when a baby is exposed to magnesium sulfate in-utero, it decreases the likelihood and severity of cerebral palsy and severe motor dysfunction in the baby.  The review involved data from over 6100 babies included in 5 trials of in-utero magnesium sulfate therapy.

Indeed, treating women at risk of preterm birth with magnesium sulfate increases the baby’s chance of being born free of cerebral palsy by as much as 32 percent.  The treatment was also found to decrease the chance of developing other major movement disabilities – severe motor dysfunction –  by about 39 percent.

When physicians suspect that a woman is going to give birth to a premature baby within 24 hours, they should start to administer magnesium sulfate.  The medication typically is administered when the baby is between 24 and 32 weeks of gestation.  Magnesium sulfate should be administered to women with preterm premature rupture of membranes (PPROM), preterm labor with intact membranes, or indicated preterm delivery.

Magnesium sulfate appears to protect the baby’s brain in a number of ways, which include the following:

  • It has antioxidant effects
  • It reduces the damaging molecules (cytokines) that are released when inflammation is present
  • It reduces a process called neuronal excitability (excitotoxicity), which is damaging to the brain and occurs when the brain experiences trauma, ischemia and oxygen deprivation
  • It stabilizes membranes in the brain
  • It prevents large blood pressure fluctuations
  • It increases cerebral (brain) blood flow

MAGNESIUM SULFATE THERAPY

When physicians determine that premature labor is imminent, a 4 gram dose of magnesium sulfate typically is given through an IV.  A dose of 1 gram (maintenance therapy) should be given every hour thereafter until the baby is born; however, the treatment should not be continued beyond 24 hours if delivery has not occurred.

If induction of labor is likely going to take longer than 24 hours, the administration of magnesium sulfate should be delayed until the cervix is ripe and the mother is closer to the time of her delivery.  When a C-section is scheduled, the initial dose should be administered and maintenance therapy can follow.  If emergency delivery is necessary due to maternal or fetal status, the delivery should not be delayed in order to administer the magnesium sulfate.

SIDE EFFECTS OF MAGNESIUM SULFATE

Magnesium sulfate is also widely used for prevention of eclampsia, so most providers are familiar with common maternal side effects, which include sweating, flushing, nausea, headache and magnesium toxicity.  Other maternal complications include the following:

  • Respiratory arrest (loss of breathing, which is life-threatening)
  • Pulmonary edema (fluid in the lungs, which is life-threatening)
  • Effects on the central nervous system
  • Hypersomnolence (excessive sleeping)
  • Muscle weakness
  • Visual changes / blurred vision
  • Loss of reflexes
  • Chest tightness

Research shows that these adverse events may occur due to unfamiliarity with safe dose ranges and signs of toxicity, inadequate patient monitoring, incorrect preparations of the drug, wrong administration technique, and mix-ups between magnesium sulfate and oxytocin.  When physicians are skilled and careful with magnesium administration, these side effects are very uncommon.

With regard to the baby, magnesium freely crosses the placenta, so the concentration of magnesium in the baby’s cord blood is about the same as the concentration in the mother’s blood.  A slight decrease in fetal heart rate and variability may be observed, but this is not clinically significant.

CONTRAINDICATIONS FOR MAGNESIUM SULFATE USE

Magnesium Sulfate for Neuroprotection: Fetal MonitorThe potential benefits of magnesium therapy should outweigh the potential risks.  Therapy is contraindicated when the mother has myasthenia gravis (a neuromuscular disease) or compromised heart function or heart conduction defects.  Since magnesium is eliminated by the kidneys, mothers with impaired kidney function may develop magnesium toxicity at the usual infusion doses.  Thus, maintenance dosing must be adjusted or eliminated for these women.

Close monitoring is essential to help prevent magnesium toxicity.  Urine output and deep tendon reflexes should be closely monitored.  The maintenance phase of treatment should be continued only if a patellar (knee) reflex is present, breathing rate exceeds 12 breaths per minute, and urine output exceeds 100 mL in four hours.

If physicians are trying to prevent preterm labor (tocolysis), indomethacin should be used because other tocolytics may have an increased risk of side effects.

MAGNESIUM SULFATE CAN HELP BABIES BE BORN WITHOUT CEREBRAL PALSY

When a mother has experienced PPROM or is at risk of having preterm birth within a 24 hour period, and her baby is only 24 – 32 weeks old, physicians must act quickly and administer magnesium sulfate during the 24 hour period, in most cases.  Overwhelming evidence illustrates the incredible benefits this therapy can have on the baby’s brain, and the therapy is in widespread use across the country.

The nationally recognized attorneys at Reiter & Walsh ABC Law Centers focus on birth injury cases like cerebral palsy and motor dysfunction. Call us today if your child suffers from any of these types of injuries.  We will review the records to determine if physicians failed to give appropriate treatments or failed to follow any other standards of care.  We will help you obtain the compensation your child deserves. Call 888-419-2229 for a free consultation.

Sources:

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  2. Nelson KB, Grether JK. Can magnesium sulfate reduce the risk of cerebral palsy in very low birthweight infants? Pediatrics 1995; 95:263.
  3. Schendel DE, Berg CJ, Yeargin-Allsopp M, et al. Prenatal magnesium sulfate exposure and the risk for cerebral palsy or cognitive impairments among very low-birth-weight children aged 3 to 5 years. JAMA 1996; 276:1805.
  4. Grether JK, Hoogstrate J, Walsh-Greene E, Nelson KB. Magnesium sulfate for tocolysis and risk of spastic cerebral palsy in premature children born to women without preeclampsia. Am J Obstet Gynecol 2000; 183:717.
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  9. Doyle LW, Crowther CA, Middleton P, et al. Magnesium sulphate for women at risk of preterm birth for neuroprotection of the fetus. Cochrane Database Syst Rev 2009; :CD004661.
  10. Costantine MM, Weiner SJ, Eunice Kennedy Shriver National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network. Effects of antenatal exposure to magnesium sulfate on neuroprotection and mortality in preterm infants: a meta-analysis. Obstet Gynecol 2009; 114:354.
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  12. Bain E, Middleton P, Crowther CA. Different magnesium sulphate regimens for neuroprotection of the fetus for women at risk of preterm birth. Cochrane Database Syst Rev 2012; 2:CD009302.
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