Stroke occurs in children at a higher rate than previously thought; however, investigations into proper preventive and acute care in pediatric patients are lacking, according to the authors of a set of treatment guidelines published in the September Stroke.
“In some situations, the treatment decisions are relatively clear, but more often the lack of randomized controlled clinical trials makes it difficult to know the best course of action,” stated E. Steve Roach, MD, Chief of the Division of Child Neurology at Nationwide Children’s Hospital in Columbus, Ohio, and colleagues.
The authors noted that children and adolescents have differences in stroke presentation, compared with adults. In adults, 80% to 85% of strokes are ischemic, and the rest are hemorrhagic, whereas in children, an estimated 55% of strokes are ischemic, and the remainder are hemorrhagic.
Risk Factors and Diagnostic Evaluation
According to the guidelines, about half of the children with stroke will have a previously identified risk factor; one or more additional risk factors can be found in many of the remaining patients. For ischemic stroke, these include sickle cell disease; congenital or acquired heart diseases; moyamoya disease; fibromuscular dysplasia; vasculitis; or hypercoagulable disorders. Migraine may also be a risk factor, although the exact contribution to stroke risk in children is unknown.
Children with thrombocytopenia or coagulation deficits have an increased risk for intracranial hemorrhage; however, the authors noted that “it is often the severity of the bleeding tendency rather than the specific defect that determines the risk.”
A hemorrhage can also develop at the site of a brain tumor, often a highly malignant neoplasm, the researchers pointed out. Unlike in adults, systemic arterial hypertension is not a common cause of brain hemorrhage in children, said the authors.
Dr. Roach and colleagues recommended that children who have had a stroke should undergo vascular imaging as soon as possible. Although there are strengths and weaknesses to each of the possible imaging modalities, including CT, MRI, PET, angiographies, and perfusion techniques, “the least invasive study that will provide an adequate assessment is usually the test to perform,” they stated.
Treatment Options
Screening of children with conditions that put a child at risk for stroke and careful treatment of these disorders may reduce the risk of primary stroke. However, in the event that one does occur, the guidelines assert that hydration and exchange transfusion are the usual treatments of acute ischemic infarction caused by sickle cell disease. In addition, for patients with moyamoya, indirect revascularization techniques are preferable for younger children, while direct bypass techniques can be used in older patients.
Revascularization surgery is also an option for patients with moyamoya who have progressive ischemic symptoms or evidence of inadequate blood flow or cerebral perfusion reserve. Control of fever, maintenance of normal oxygenation, control of systemic hypertension, and normalization of serum glucose levels are recommended as supportive therapy after acute ischemic stroke.
“Management options for children with nontraumatic intracranial hemorrhage fall into two categories,” continued Dr. Roach and coauthors.
The first option is stabilization of the patient, which includes optimizing the respiratory effect, controlling systemic hypertension, preventing epileptic seizures, and medically managing increased intracranial pressure. The second option is to reduce the risk of rebleeding. Correction of treatable risk factors should reduce the likelihood of additional bleeding; there is no evidence that surgery to remove a hematoma will help.
Outcome After Childhood Stroke
Six percent to 15% of children will have a recurrent event, said Dr. Roach and colleagues. They also noted that between 20% and 40% of children will die as a result of a stroke, and mortality is even higher in those with recurring stroke. Anticoagulation with low-molecular-weight heparin and warfarin can be used long term in children with a substantial risk of recurrent cardiac embolism, the guidelines stated, while aspirin (3 to 5 mg/kg/day) can be used as a secondary preventive measure in children with arterial ischemic stroke not caused by sickle cell disease or in children who have a high risk of recurrent embolism or a severe hypercoagulable disorder.
Between 50% and 80% of children who survive a stroke will have neurologic sequelae. Neuropsychologic deficits, poor attention, behavioral problems, and poor quality of life are also possible. “Early evaluation of physical and cognitive disability is the key to preventing avoidable complications and to planning rehabilitation, which should involve a multidisciplinary team,” the writing committee said.
Dr. Roach and coauthors predicted that these guidelines will need to be updated in a few years. “Continued research and additional experience are imperative if we are to better understand this important group of conditions,” they concluded.
—Jessica Dziedzic