Perinatal Arterial Ischemic Stroke (PAIS)

Perinatal Arterial Ischemic Stroke (PAIS) is a type of pediatric stroke that occurs between 20 weeks gestation and 28 days postnatal life. It is caused by a disruption in blood flow to a major cerebral artery, resulting in an area of damaged cerebral tissue. Causes may include thrombosis (blood clotting), embolism (sudden blocking of an artery), trauma, hypoxic-ischemic encephalopathy, vasospasm (narrowing of the arteries caused by a persistent contraction of the blood vessel), or infection. The middle cerebral artery (MCA) is the most common blood vessel involved in PAIS. This large artery supplies blood to the parts of the brain that control the primary motor and sensory areas of the face, throat, hand, and arm, as well as three areas that control speech. An MCA stroke typically results in a sudden onset of neurological deficits. Perinatal stroke occurs in 1 in 2,300 to 1 in 5,000 live births.

Perinatal strokes can also be caused by medical negligence during labor and delivery. Excessive use of force may cause trauma to the infant in vaginal or instrumental deliveries, potentially resulting in a major cerebral artery tear, transmitting blood into the brain. This is known as a cerebral arterial dissection, a leading cause of stroke in children. Drugs commonly used to induce labor, such as Pitocin, can cause excessive uterine activity and/or prolong labor. Excessive contractions may compress the infant’s head, resulting in oxygen deprivation to the baby or cardiac impairment. Ultimately, these complications may lead to cerebral ischemia (inadequate blood supply). Trauma from head compression may also be the result of cephalopelvic disproportion (CPD). A disparity between the size of the fetus and the maternal pelvis may alter the progress of labor—increasing the risk of stroke.

Studies suggest that maternal risk factors for PAIS include primiparity (when a mother is giving birth to her first child), infertility, chorioamnionitis, prolonged rupture of membranes, preeclampsia, and intrauterine growth retardation (less than 10 percent of predicted fetal weight for gestational age).

Newborns that have suffered from PAIS most frequently present symptoms in the form of seizures and weakness in the right or left side of the body. Complications from PAIS may result in devastating injuries to newborns, including a substantial risk for abnormal neurodevelopment. PAIS is a well-recognized cause of cerebral palsy, epilepsy, behavioral abnormalities, impaired vision, and neonatal morbidity or mortality.

As PAIS is a known cause of long-term neurological impairment, it is crucial that a thorough physical examination and MRI of the brain are completed to evaluate a child’s condition. Early treatment to help to improve functional outcomes for children with PAIS may include physical, speech, and occupational therapies.