title: Evaluation of the yield stress of normal blood as a function of fibrinogen concentration and hematocrit.
abstract: The yield stress is a sensitive index of blood fluidity at low shear. Seven healthy adults were studied at hematocrits varying between 40 and 80% and fibrinogen concentrations from 0.0 to 0.935 g/dl. Multivariable analysis was used to determine the functional dependence of yield stress on hematocrit and fibrinogen level. The major findings from this analysis include a decreasing effect of fibrinogen at high concentrations (saturation effect), a relative insensitivity of yield stress to fibrinogen at low concentration (threshold effect), and a strong interaction between the effects of hematocrit and fibrinogen concentration on yield stress. Our results give the normal range of yield stress for a given value of fibrinogen and hematocrit and can be used to predict the effect of reductions in hematocrit or fibrinogen on the yield stress of normal blood.
authors.affiliation: Department of Hematology/Oncology, Children's Hospital Medical Center, Cincinnati, Ohio 45229-2899.
authors.forename: C L
authors.initials: CL
authors.lastname: Morris
authors.forename: D L
authors.initials: DL
authors.lastname: Rucknagel
authors.forename: R
authors.initials: R
authors.lastname: Shukla
authors.forename: R A
authors.initials: RA
authors.lastname: Gruppo
authors.forename: C M
authors.initials: CM
authors.lastname: Smith
authors.forename: P
authors.initials: P
authors.lastname: Blackshear
mesh_terms: D000328:Adult; D001783:Blood Flow Velocity; D001809:Blood Viscosity; D005340:Fibrinogen / Q000378:metabolism*; D006400:Hematocrit; D006801:Humans; D066298:In Vitro Techniques
chemical_list: D005340:Fibrinogen