Erythrocyte sedimentation rate and blood viscosity as modified by fat emulsions

The effect of lecithin and lecithin-free intravenous fat emulsions on erythrocyte sedimentation and blood viscosity was investigated. Lecithin-emulsified cottonseed oil markedly depressed erythrocyte sedimentation and increased blood viscosity of human and dog blood. This effect was only temporary and the erythrocyte sedimentation rate returned to normal within 24 hours as determined by an in vivo study with dogs. The erythrocyte sedimentation rate of human and dog erythrocytes incubated in cottonseed oil emulsified with polyethylene glycol stearate, more closely resembled that of whole blood. Blood viscosity decreased in the presence of this emulsifier. It is conclude that the influence of lipemia on erythrocyte sedimentation and blood viscosity is due to the emulsifier rather than the oil component of the chylomicron.

PLASMA TRAPPING IN THE CENTRIFUGED RED CELLS OF CHILDREN WITH SEVERE THALASSAEMIA

The amount of trapped plasma, expressed as a percentage of the packed cell volume, was determined in samples of heparinized blood from 26 children with severe thalassaemia and from 37 normal children over a wide range of artificial packed cell volumes. There was invariably more plasma trapped among the centrifuged red cells of the thalassaemic children, the mean difference between normal and thalassaemic children being 1% of the packed cell volume. In both normal and thalassaemic children the volume of trapped plasma, expressed as a percentage of the packed cell volume, was directly proportional to the packed cell volume. Plasma trapping did not appear to be related to the size of the erythrocytes in either the normal or the thalassaemic children. It varied inversely with the density of the red cells, as estimated by their mean haemoglobin concentration, in the thalassaemic children.

THE EFFECT OF AGE ON NORMAL VALUES OF THE WESTERGEN SEDIMENTATION RATE

Westergren sedimentation rates were done on 603 healthy blood donors. The results showed an increase in the normal values with age. The normal values found in this series were higher than those generally accepted as normal.