Publications & Reports

Cord whole blood hyperviscosity: measurement, definition, incidence and clinical features.

Drew JH, Guaran RL, Grauer S, Hobbs JB
Department of Paediatrics, Mercy Maternity Hospital, East Melbourne, Victoria, Australia.


Cord whole blood viscosity and haematocrit values (PCV) were determined in 2461 live birth infants. Viscosity measurements were performed on an Australian-designed coaxial narrow-gap viscometer. Normal viscosity values were determined for each week of gestation above 34 weeks. Hyperviscosity was defined as a viscosity value above 2 s.d. from the mean for each week of gestation and it occurred in 164 (6.7%) newborn infants. Although a close relationship existed between cord whole blood viscosity and PCV (r = 0.6597, P less than 0.0001), only 47.4% of polycythaemic infants (PCV greater than 65) were also hyperviscous and only 23.9% of hyperviscous infants were also polycythaemic. Hence, using the haematocrit to select which infants require viscosity studies fails to detect many hyperviscous newborn infants. Hyperviscosity was less common (3.6%, P less than 0.001) in infants who were born by Caesarean section and more common (16.5%, P less than 0.001) in those who were growth retarded. Of the hyperviscous infants, 84.5% were not growth retarded, most (87.8%) were term and most (86.6%) were delivered vaginally. Most hyperviscous newborn infants may thus remain undetected unless routine whole blood viscosity studies are performed.


  • Journal: Journal of Paediatrics and Child Health
  • Published: 01/12/1991
  • Volume: 27
  • Issue: 6
  • Pagination: 363-365