BACKGROUND Cardiovascular complications are common in patients with obstructive sleep apnea (OSA). Blood rheology is a major determent of coagulation and an established risk factor for cardiovascular events. Since nocturnal hypoxemia could influence parameters of blood rheology, we hypothesized that OSA alters blood rheology independent of other cardiovascular risk factors. METHODS One hundre...

A prospective study was undertaken to establish the haematologicakand haemorheological changes associated with long standing cigarette smoking in 20 heavy smokers and to assess whether any such changes were reversible after smoking was stopped. Highly significant differences were observed in whole blood viscosity, plasma viscosity, plasma fibrinogen concentrations, packed cell volume, and carbo...

Since alterations in cell-plasma ratios are of paramount importance in the assessment of periplieral resistance, a study of pressure-flow relations was made in which blood having wide hematocrit values was perfused through a dog's hind limb in which collateral circulation has been excluded. When vessels were moderately dilated by denervation, the relative apparent viscosity was not affected by ...

Plasma fibrinogen concentration and whole-blood viscosity, the latter measured at two shear rates (23 and 230 sec-1), were estimated during eight episodes of sickle-cell crisis and compared with values in 26 sickle-cell anaemia patients who were not in crisis. Painful crisis was associated with a significant increase in both plasma fibrinogen and whole-blood viscosity. Increased fibrinogen-eryt...

Hagfish have an unusual circulation with intravascular pressures that are lower than those in other vertebrates (Davie et al. 1987; Forster, 1989) and since peripheral resistances appear similar to those of teleost fishes (Rood, 1979; Elger, 1987), it follows that blood flow rates will also be lower. One might therefore predict that the relatively low haematocrits in hagfish (Johansen et al. 19...

The importance of viscosity in determining plasma flow structures has been widely recognized. In laboratory plasmas, however, viscosity measurements have been seldom performed so far. In this paper we present and discuss an estimation method of effective plasma kinematic viscosity utilizing flow velocity field measurements. Imposing steady and axisymmetric conditions, we derive the expression f...

Increased oxidative damage has been suggested to play an important role in the viscosity changes of blood. However, changes in levels of oxidative damage products in semen and their relationship to seminal fluid viscosity are unknown. The aim of our study was to investigate whether oxidative damage was associated with seminal plasma viscosity in infertile subjects. The levels of malondialdehyde...