title: Transcranial Doppler ultrasonography in children with sickle cell anemia: Clinical and laboratory correlates for elevated blood flow velocities.
abstract: BACKGROUND
  Transcranial Doppler (TCD) sonography of major cerebral arteries is now recommended for routine screening for stroke risk in children with sickle cell disease (SCD).
  
  
  METHODS
  We performed TCD studies on children with sickle cell anemia (SCA) seen at the pediatric hematology clinic over a period of 2 years. TCD scans were repeated yearly in children with normal flow velocities and every 3 months in children with elevated velocities. Findings were correlated with clinical variables, hematologic indices, and arterial oxygen saturation. Predictors of elevated velocities were identified by multiple linear regressions.
  
  
  RESULTS
  We enrolled 237 children and performed a total of 526 TCD examinations. Highest time-averaged maximum flow velocities were ≥170 cm/s in 72 (30.3%) cases and ≥200 cm/s in 20 (8.4%). Young age, low hematocrit, low hemoglobin, and arterial oxygen desaturation <95% showed significant correlations with presence of increased cerebral flow velocities.
  
  
  CONCLUSIONS
  Low hematocrit, low hemoglobin concentration, young age, and low arterial oxygen desaturation predicted elevated cerebral blood flow velocities and, invariably, increased stroke risk, in children with SCA. Children who exhibit these features should be given high priority for TCD examination in the setting of limited resources.
authors.affiliation: Department of Paediatrics, College of Medicine, University of Ibadan, Ibadan, Nigeria; Department of Paediatrics, University College Hospital, Ibadan, Nigeria.
authors.forename: IkeOluwa
authors.initials: I
authors.lastname: Lagunju
authors.forename: Olugbemiro
authors.initials: O
authors.lastname: Sodeinde
authors.forename: Biobele
authors.initials: B
authors.lastname: Brown
authors.forename: Felix
authors.initials: F
authors.lastname: Akinbami
authors.forename: Babatunde
authors.initials: B
authors.lastname: Adedokun
mesh_terms: D000293:Adolescent; D000367:Age Factors; D000755:Anemia, Sickle Cell / Q000097:blood / Q000150:complications / Q000000981:diagnostic imaging* / Q000503:physiopathology; D015415:Biomarkers / Q000097:blood; D001783:Blood Flow Velocity; D002536:Cerebral Arteries / Q000000981:diagnostic imaging* / Q000503:physiopathology; D002648:Child; D002675:Child, Preschool; D003906:Developing Countries; D005260:Female; D006297:Health Services Accessibility; D006400:Hematocrit; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D016014:Linear Models; D008297:Male; D010100:Oxygen / Q000097:blood; D011446:Prospective Studies; D018570:Risk Assessment; D012720:Severity of Illness Index; D020521:Stroke / Q000209:etiology / Q000517:prevention & control*; D017585:Ultrasonography, Doppler, Transcranial
chemical_list: D015415:Biomarkers; D006454:Hemoglobins; D010100:Oxygen
keywords: Doppler; anemia; children; sickle cell; transcranial