Hemoglobin

Cerebrovascular Accident in Sickle Cell Anemia

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Cerebrovascular Accident in Sickle Cell Anemia, CVA in Sickle Cell Disease, Silent Cerebral Infarction in Sickle Cell Anemia

  1. Sickle Cell Anemia is the most common cause of CVA in Children
  2. Children: 5%
    1. Highest risk at ages 2 to 5 years old with Sickle Cell Anemia
    2. Clinically apparent stroke occurs in 10% by age 5 years old
      1. Baskin (2013) Pediatrics 131(6): 1035-41 [PubMed]
    3. Silent cerebral infarct occurs in up to 25% of children by age 6 years old
      1. May result in gradual cognitive decline
  3. Young adult (age <20): 11%
  4. Age 45 years old: 24%
  5. Lifetime risk: 25%
  • Pathophysiology
  1. Silent Cerebral Infarction
    1. Silent CVA may occur in up to 25% of children with Sickle Cell Anemia by age 6 years old
    2. May present as cognitive deficits or learning difficulties
    3. May be prevented with regular Blood Transfusions (see below)
  2. Ischemic Stroke
    1. Most common in children and teens
    2. Internal Carotid Artery thrombosis
  3. Hemorrhagic Stroke
    1. Most common in ages 20 to 30 years old
  • Risk Factors
  1. Prior Transient Ischemic Attack
  2. Chronic low baseline Hemoglobin (below typical Sickle Cell Anemia levels)
  3. Recent Acute Chest Syndrome
  4. Hypertension
  5. Mean cerebral arterial flow velocities high (transcranial Doppler Ultrasound)
  6. Family History of Cerebrovascular Accident
  • Symptoms
  1. Ischemic CVA
    1. Behavior change
    2. Persistent Headache
  2. Hemorrhagic CVA
    1. Severe Headache
    2. Loss of consciousness
  • Signs
  1. Dysarthria or other speech difficulty
  2. Focal weakness
  3. Ataxia or Abnormal Gait
  4. Vision change
  • Labs
  1. Bedside Glucose (and treat Hypoglycemia if present)
  2. Serum chemistry panel
  3. Complete Blood Count
  4. Reticulocyte Count
  5. Blood Type and Screen
  6. Blood Cultures (febrile patients)
  • Imaging
  1. Transcranial Doppler Ultrasound
    1. Routine screening starts at age 2 years to at least age 16 years old
    2. Evaluate transcranial Blood Flow velocity (TBV)
      1. High CVA risk (10% increased risk) suggested by TBV >200 cm/sec (marginal if 170-199 cm/s)
  2. CT Head or MRI Head (depending on timing of presentation)
    1. Indicated for suspected acute cerebrovascular event
  3. MR Venogram
    1. Evaluate for venous sinus thrombosis if indicated
  • Differential Diagnosis
  • Management
  1. Rapid diagnosis and consult neurology stroke team
    1. Adult with Ischemic CVA
      1. See CVA Thrombolysis
      2. Sickle Cell Disease is not a contraindication to tPA
      3. tPA may be used where indicated
      4. Aspirin may be used in adults with CVA
    2. Child with Ischemic CVA
      1. No studies to guide the use of tPA or Aspirin in children (case reports only)
      2. Consult stroke neurology
  2. Supplemental Oxygen
    1. Maintain Oxygen Saturation >95%
  3. Intravenous Fluids
    1. Start 1 to 1.5x maintenance, titrating to Urine Output and euvolemia
  4. Febrile patients
    1. Evaluate for source
    2. Empiric Antibiotics after cultures
  5. Consider exchange transfusion or standard Blood Transfusion
    1. Base on Hemoglobin At presentation compared with baseline
    2. Risk of Transfusion-associated volume/circulatory overload (TACO)
  • Prevention
  1. Regular follow-up with hematology (and possibly neurology)
  2. Consider Hydroxyurea
  3. Chronic exchange transfusions (monthly)
    1. Reduce proportion of Hemoglobin S <50%
    2. Maintain this level through childhood
  • Prognosis
  1. Risk of recurrent CVA within one year in up to 60% of cases
  • References
  1. Claudius, Behar and Sadowitz in Herbert (2018) EM:Rap 18(4): 10-2
  2. Welsh and Welsh (2016) Crit Dec Emerg Med 30(11): 15-23
  3. Adams (1998) N Engl J Med 339:5-11 [PubMed]