title: Haematocrit values and blood viscosity in the newborn infant.
abstract: The haematocrit values in 51 babies were studied to observe the possible variations due to the method and time of sampling and to relate these findings to blood viscosity. A good correlation (r = 0,9536) between haematocrit values of warmed heel capillary blood and of central venous samples was found. Prediction of venous value from a known sample of capillary blood can be made using regression lines and 95% confidence limits. The correlation between venous and unwarmed blood samples from the heel is not as good. A central venous haematocrit value of 65% or greater gave a 100% risk of the infant's blood being hyperviscous. Hyperviscosity occurred in 71% of infants with a capillary haematocrit value of 65 - 68% but the figure rose to 81% when the peripheral haematocrit value was 68% or more.
mesh_terms: D001800:Blood Specimen Collection / Q000379:methods; D001809:Blood Viscosity; D005260:Female; D006400:Hematocrit / Q000379:methods; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D011086:Polycythemia / Q000175:diagnosis