Early support from a diverse team of clinicians is key to successfully managing pregnancy in women with myasthenia gravis, particularly if a pregnancy is complicated by pre-eclampsia, a case report highlights.
The report recommends that pregnant women with the disease receive epidural analgesia in labor to prevent fatigue, and that they switch from oral Mestinon (pyridostigmine), a medicine for myasthenia gravis, to intramuscular injections during labor.
The case study, titled “Emergency caesarean section in a woman with myasthenia gravis and pre-eclampsia,” was published in the British Journal of Hospital Medicine.
Two anesthetists at the Royal Bolton Hospital, in the U.K., describe the case of a 41-year-old woman with myasthenia gravis who was at the end of her pregnancy when she was admitted to an obstetric unit for an emergency cesarean delivery.
The women already was a mother of five children and had uncomplicated deliveries before she was diagnosed with myasthenia gravis.
A few days before inducing labor, she was admitted to the hospital due to to a diagnosis of pre-eclampsia, or high blood pressure and damage to other organs, frequently including the kidneys and the liver. Pre-eclampsia can lead to serious, even fatal, complications for both the mother and the child.
The clinical team decided to rush the delivery with a cesarean procedure because the women suddenly complained of strong abdominal pain, which was seen to be associated with fetal bradycardia, a slower-than-normal heart rate of the fetus.
This was a sign, later confirmed, that the placenta had separated prematurely from the uterus, which can decrease or block the baby’s supply of oxygen and nutrients and cause heavy bleeding in the mother.
Normally, myasthenia gravis would contraindicate the use of general anesthesia, as many anesthetics can exacerbate the disease.
However, in this case, the clinical team, which included the anesthetists, agreed to use it given the risk of extensive bleeding by the mother.
Physicians also decided not to administer magnesium, a substance commonly used to manage pre-eclampsia, as it could also worsen myasthenia gravis.
After delivery, the patient began to present symptoms of respiratory distress, including a sensation of a lump in the throat, shortness of breath, and low oxygen levels in the blood.
Throughout this period, the patient continued to have high blood pressure until she was successfully treated with hydralazine.
Recovery was longer than normal due to generalized weakness and fatigue, but the mother was discharged five days after delivery.
All women with myasthenia gravis should be counseled about the benefits of epidural analgesia, the two anesthetists recommended in the study. This will help prevent fatigue during labor and enable surgical anesthesia if required, they said.
If epidural analgesia isn’t possible, then short-acting opioid analgesia, such as Ultiva (remifentanil), is preferred.
Reinitiation of treatment with Mestinon (pyridostigmine), stopped early during pregnancy, may be done during labor, but intramuscular instead of oral administration should be considered due to altered stomach-emptying during labor, the report said.
“As the age of first-time mothers continues to rise clinicians will see more patients with an established diagnosis of myasthenia gravis at risk of pre-eclampsia,” the researchers noted.
The two anesthetists stressed that “a sensible risk assessment will be required in the management of these patients.”
The anesthetic team should work closely with a multidisciplinary team of clinicians to plan labor and delivery, they added.