Pediatric emergency medicine trisk 658
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Coagulopathies (e.g., hemophilia)
Anticoagulant deficiency (protein C, protein S, antithrombin III)
Polycythemia
Acute myelogenous leukemia
Systemic lupus erythematosus
Neurocutaneous syndromes
Neurofibromatosis
Tuberous sclerosis
Sturge–Weber syndrome
Clinical Considerations
Clinical Recognition
The presentation of stroke in children is highly variable, and is influenced by the
child’s age and the portion of the cerebral vasculature affected. Facial weakness,
arm weakness, and inability to walk have been associated with increased
likelihood of stroke. In neonates and young children, however, seizure may be the
only presenting symptom. Involvement of the anterior cerebral artery leads
primarily to lower-extremity weakness, whereas compromise of the middle
cerebral artery circulation produces hemiplegia with upper limb predominance,
hemianopsia, and possibly dysphasia. Less commonly, the posterior circulation is
affected, which results in vertigo, ataxia, and nystagmus, as well as hemiparesis
and hemianopsia. Older children often have concomitant headache. The child
with a stroke may also have a diminished level of consciousness.
Triage Considerations
Any child with an acute neurologic deficit requires prompt evaluation. Suspicion
for stroke should be increased in children with predisposing medical conditions
such as sickle cell disease and congenital cardiac disease.
Clinical Assessment
Because stroke can have a highly variable and at times subtle presentation, a
thorough neurologic examination is necessary in any patient presenting with a
neurologic deficit, seizure, or alteration of consciousness. Any new neurologic
symptom or complaint in patients with underlying sickle cell disease merits close
evaluation. Particular attention should be paid to identifying risk factors as the
majority of children have at least one identifiable risk factor at the time of
infarction. In addition, physicians need to consider other etiologies that may
mimic stroke, including complicated migraine, structural brain lesion, central
nervous system (CNS) infection, Todd paresis, and psychogenic causes (see
Chapters 17 Coma and 82 Weakness ).
Diagnostic Testing
Investigations in a child for whom there is a concern for stroke should be directed
at confirming the diagnosis of stroke and attempting to identify an underlying
cause. Cross-sectional neuroimaging is recommended for all children with
suspected stroke. MRI with diffusion-weighted imaging is considered the most
sensitive imaging modality and can identify ischemic changes within hours of
onset. Limited, or Quick brain MRI with DWI series has demonstrated good
sensitivity for the identification of acute ischemic stroke, however, it is not as
sensitive in the identification of hemorrhage, which may limit its role for those
patients for whom thrombolysis is a consideration. Cranial CT without contrast is
the study of choice for identifying acute hemorrhage; however, CT scan may be
normal in the first 12 to 24 hours after an ischemic stroke. Vascular imaging of
the cervical vessels as well as proximal intracranial vessels should be included.
This can be done with magnetic resonance angiography in most patients. MRV
imaging should be strongly considered as a significant proportion of hemorrhages
are secondary to cerebral venous sinus thrombosis. Several factors should be
considered in the choice of initial imaging modality; radiation exposure,
sensitivity, and specificity in identifying acute ischemia and hemorrhage, ability
to complete in a timely manner, the need for anesthesia, and consideration of
thrombolytic therapy. In a child without a known predisposing condition,
ancillary tests may be helpful in revealing the cause of the stroke. Studies worth
considering in such patients, depending on the clinical picture, are listed in Table
97.6 . In one series of 129 children with ischemic stroke, no cause was found in
35%.
Management
Initial treatment after an acute stroke should focus on stabilization and prevention
of secondary neuronal injury. This includes maintenance of normotension,
normothermia, euglycemia, and treatment of hypoxemia and seizures.
Hypertension must be treated cautiously, and the blood pressure lowered
gradually in order to maintain adequate cerebral perfusion. Both hypoglycemia
and hyperglycemia can exacerbate ischemic stroke. Careful monitoring of serum
glucose levels and judicious use of insulin are important. Fever, which can occur
in children with stroke, may also contribute to ischemic damage and should be
controlled with antipyretics.
TABLE 97.6
STUDIES TO CONSIDER IN THE EVALUATION OF THE CHILD
WITH ACUTE STROKE
Brain imaging
Computed tomography (noncontrast)
Magnetic resonance imaging
Angiography (standard or magnetic resonance)
Cardiac
Electrocardiogram
Echocardiogram
Hematologic
Complete blood cell count
Prothrombin and partial thromboplastin times
Fibrinogen
Erythrocyte sedimentation rate
Hemoglobin electrophoresis
Protein C and S quantification
Antithrombin III level
Chemistry
Blood urea nitrogen
Cholesterol and triglycerides
Hepatic transaminases
Serum amino acids
Urine organic acids
Toxicology screen
Lactate
Lumbar puncture
In consultation with a pediatric hematologist, anticoagulation therapy should be
strongly considered, once hemorrhagic stroke is excluded. Current pediatric
guidelines recommend the use of aspirin, low–molecular-weight heparin, or
unfractionated heparin. The choice of acute anticoagulation treatment as well as
long-term preventative therapy is influenced by stroke etiology as well as the
presence of a cardioembolic cause or arterial dissection.
Further therapy is determined by the type of stroke. Neurosurgical intervention
may be required to evacuate a hematoma or control a bleeding arteriovenous
malformation (AVM). Catheter-directed embolization may also be possible in
cases of AVM. Children with sickle cell disease and stroke should have acute
transfusion to decrease the level of hemoglobin S to less than 30%. Novel
therapies such as calcium channel blockers and free radical scavengers have not
been studied in pediatric patients and their use remains experimental.
Regardless of treatment, long-term morbidity of stroke in children is high, with
more than 75% of affected children experiencing sequelae such as hemiparesis,
seizures, and learning difficulties. Overall, prognosis for children with stroke is
better than that in adults.
