title: Determinants of blood rheology in healthy adults and children using the microchannel array flow analyzer.
abstract: OBJECTIVE
  The reference values of blood rheology in healthy participants, especially children, are not available. The purpose of this study was to determine the blood passage time (BPT) as an index of blood rheology, in healthy children and adults, using the microchannel array flow analyzer, and to investigate the hematological factors that define BPT.
  
  
  METHODS
  Participants were 61 healthy children (35 boys, 26 girls; age 5-6 years) and 71 healthy adults (24 men, age 35.2 +/- 14.1 years; 47 women, age 44.7 +/- 14.1 years, mean +/- standard deviation [SD]). Blood passage time and various hematological variables (blood cell count, serum lipids, and fibrinogen) were measured and compared among the 4 study groups.
  
  
  RESULTS
  Blood passage time values were significantly higher in adult men (48.8 +/- 5.8 seconds) than in boys (41.9 +/- 4.0 seconds), girls (43.7 +/- 7.8 seconds), and adult women (42.4 +/- 4.8 seconds). Stepwise regression analysis identified erythrocyte count and hemoglobin (Hb) as the significant and independent determinants of BPT (P < .05).
  
  
  CONCLUSIONS
  Our study demonstrates that BPT is significantly longer in healthy adult men than in adult women and children, and that erythrocyte count and Hb are significant determinants of blood rheology.
authors.affiliation: Faculty of Education, Kogakkan University, Ise, Mie, Japan. katayama@kogakkan-u.ac.jp
authors.forename: Yasutomi
authors.initials: Y
authors.lastname: Katayama
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Horigome
authors.forename: Hideto
authors.initials: H
authors.lastname: Takahashi
authors.forename: Kiyoji
authors.initials: K
authors.lastname: Tanaka
authors.forename: Masao
authors.initials: M
authors.lastname: Yoshinaga
mesh_terms: D000328:Adult; D000367:Age Factors; D001775:Blood Circulation / Q000502:physiology*; D001783:Blood Flow Velocity / Q000502:physiology; D001809:Blood Viscosity / Q000502:physiology*; D002648:Child; D002675:Child, Preschool; D005260:Female; D018056:Hemorheology; D006801:Humans; D008297:Male; D011379:Prognosis; D012044:Regression Analysis; D012737:Sex Factors