Clinical Hemorheology and Microcirculation - Volume 16, issue 6

Authors: Gustavsson, Carl G. | Persson, Sylvi U. | Larsson, Hans | Persson, Stig | Thorvinger, Björn O. S.

Article Type: Research Article

Abstract: The effects of coronary angiography with iohexol upon vein blood rheology were studied before, immediately after and one month after angiography. Haematocrit decreased from 40.5% to 39.0% immediately after angiography (p < 0.01). When this was compensated for by in vitro standardisation of sample haematocrits to 45% there was a blood viscosity increase by 10.9 – 15.0%, at the four studied shear rates 0.8 s−1 , 2.3 s−1 , 19.6 s−1 , and 40.0 s−1 (p < 0.05 – p < 0.01). In unadjusted samples, i.e. at the patients natural haematocrits, there was only a slight and statistically non-significant …blood viscosity increase. Plasma viscosity decreased immediately after angiography, and was even lower 1 month after angiography. The haematocrit reduction correlated significantly with the iohexol doses (correlation coefficient −0.852, p < 0.001), whereas no significant correlation was found between the contrast volumes and the alterations of blood and plasma viscosity. Except for plasma viscosity, there were no significant differences when the values before angiography and one month later were compared. Show more

Keywords: blood viscosity, contrast media, iohexol, coronary angiography, haematocrit, haemorheology

DOI: 10.3233/CH-1996-16601

Citation: Clinical Hemorheology and Microcirculation, vol. 16, no. 6, pp. 737-743, 1996

Authors: Schmid-Schönbein, H. | Ruef, P. | Linderkamp, O.

Article Type: Research Article

Abstract: The Rheodyn SSD is an automated laser diffractometer for rapid measurement of red blood cell (RBC) deformability in small quantities of blood. RBC are suspended in a viscous medium and placed between a rotating and a stationary disk. Defined shear stresses of 0.3 to 60 Pa force the RBC to deform to ellipsoids, causing elliptical diffraction pattern of a laser beam passing through the RBC suspension. At shear stresses of 3 to 60 Pa, coefficient of variation was <3% for repeated measurements of the same blood sample. RBC deformation was not affected by the anticoagulant (no anticoagulant, heparin, EDTA, or …citrate), the sample size (10 to 50 μl of blood) and washing of RBC. The results show that the Rheodyn SSD is a reproducible tool to study RBC deformability in small blood samples. Show more

Keywords: anticoagulants, erythrocyte deformability, Rheodyn, shear stress diffractometer

DOI: 10.3233/CH-1996-16602

Citation: Clinical Hemorheology and Microcirculation, vol. 16, no. 6, pp. 745-748, 1996

Authors: Ruef, P. | Pöschl, J.M.B. | Linderkamp, O. | Schmid-Schönbein, H.

Article Type: Research Article

Abstract: Instruments for measurement of red blood cell deformability (RBC) should be sensitive to detect both a moderate reduction in cellular deformabiltiy of the entire RBC population and of a subpopulation of rigid RBC. The sensitivity of the laser diffractometer Rheodyn SSD was tested by treatment of normal RBC with increasing concentrations of glutaraldehyde, mixing of normal RBC with increasing percentages of rigid RBC, and by density separation of normal RBC. Maximum RBC elongation (at a high shear stress of 60 Pa) decreased from 60 to 8 when increasing the glutaraldehyde concentration from 0 to 0.004%. For every 10% of rigid …RBC, mean RBC elongation decreased by about 10%. Density-separated RBC showed a typical deformation behavior: “top” cells were better deformable than “bottom” cells over the whole range of applied shear stresses. The results show that the Rheodyn SSD is a sensitive tool to detect abnormal RBC deformability. Show more

Keywords: Density-separated erythrocytes, erythrocyte deformability, glutaraldehyde, shear stress diffractometer

DOI: 10.3233/CH-1996-16603

Citation: Clinical Hemorheology and Microcirculation, vol. 16, no. 6, pp. 749-752, 1996

Authors: Baskurt, Oguz K. | Fisher, Timothy C. | Meiselman, Herbert J.

Article Type: Research Article

Abstract: The sensitivity of the Cell Transit Analyzer (CTA) to the alterations of red blood cell (RBC) deformability and related factors was investigated. Using 5 μm pore size filters the CTA was found to be more sensitive to slight glutaraldehyde-induced decreases of deformability for rat RBC in comparison with larger human RBC. However, using 3 μm pore size filters decreased the sensitivity of measurements to mechanical changes of rat RBC, implying that a lower cel/pore size ratio might provide better sensitivity. Exclusion of a subpopulation of the most rigid cells, which are not able to pass through the pores might be …involved. Measurements using RBC suspensions with various cell counts revealed that RBC concentration in the suspension being filtered was an important determinant of CTA sensitivity, especially for measurements on human RBC using 5 μm pore size filters. The insensitivity of CTA to slight changes in deformability might, in part, be related to the higher probability of longer pulses being rejected as a result of coincidence. Either decreasing the cel/pore size ratio or limiting the cell count in the suspensions being filtered might optimize the sensitivity of the CTA to slight degrees of mechanical alterations in human RBC. Show more

Keywords: Cell Transit Analyzer, red blood cell deformability, sensitivity, glutaraldehyde

DOI: 10.3233/CH-1996-16604

Citation: Clinical Hemorheology and Microcirculation, vol. 16, no. 6, pp. 753-765, 1996

Authors: Trapani, M. | Moncini, M. | Cameli, A.M. | Zorn, A.M. | Dorigo, W. | Mannaioni, P.F. | Dorigo, B.

Article Type: Research Article

Abstract: The aim of this study is to compare the values of hematologic and hemorheologic parameters in preclinic alcoholists, i.e. without or with limited liver damage (moderate steatosis in 38% of the cases), in basal conditions and after alcohol withdrawal for 30 days. In 21 alcoholists whole blood viscosity (WBV), whole blood filtration total time (TT), hematologic and biochemical blood tests were studied. The results show in basal condition an increase in WBV, TT and mean cell volume (MCV). After the period of abstention from alcohol, WBV significantly decreased (P<0.025), TT became shorter (P<0.025), MCV significantly reduced (P<0.025). The abnormalities …of hemorheologic parameters in these alcoholists may be attributable to the effect of alcohol itself, because in these subjects neither usual hemorheological risk factors nor chronic liver disease have been demonstrated and improvement of hemorheologic parameters appear after a period of alcohol abstention for 30 days without any medical treatment. Show more

Keywords: alcoholism, whole blood viscosity, whole blood filtration, alcohol abstention

DOI: 10.3233/CH-1996-16605

Citation: Clinical Hemorheology and Microcirculation, vol. 16, no. 6, pp. 767-773, 1996

Authors: van Leest, L.A.T.M. | Delemarre, F.M.C. | Steegers, E.A.P. | Jongsma, H.W. | van Dop, P.A. | Goslinga, H.

Article Type: Research Article

Abstract: Longitudinal physiologic changes in blood viscosity parameters were studied in 9 women with uneventful pregnancies. After an initial decrease in blood viscosity, an increase towards the end of pregnancy was found. The oxygen-transport capacity remained quite constant during pregnancy with a small rise at gestational week 32. A cross-sectional study was performed in 102 pregnant women at 28 weeks gestation. Chronic dietary sodium restriction did not influence blood viscosity significantly. No significant relationships were found between hemorheologic parameters and parity, prematurity and fetal growth retardation. Higher blood viscosity was found in women who became hypertensive in pregnancy, even …before the onset of the disease. Show more

Keywords: blood viscosity, hemorheology, pregnancy

DOI: 10.3233/CH-1996-16606

Citation: Clinical Hemorheology and Microcirculation, vol. 16, no. 6, pp. 775-788, 1996

Authors: Fiorelli, G. | Turrini, F. | Mannu, F. | Porro, F. | Graziadei, G. | Tavazzi, D. | Duca, L. | Cappellini, M.D.

Article Type: Research Article

Abstract: The erythrocyte membrane alterations were studied in nineteen beta-thalassemia intermedia patients. Solubilized erythrocyte membrane proteins were gel-filtered and high-molecular-weight aggregates were isolated and analyzed for denatured hemoglobin derivatives. All the patients presented increased amounts of membrane-bound heme, hemichromes and immunoglobulins, together with aggregation and oxidation of band 3. The basal activity of the erythrocyte pentose-monophosphate-pathway was normal, whereas a lower susceptibility to in vitro methylene blue stimulation was observed. In five randomly-selected patients, whole blood viscosity resulted approximately normal, while filterability was significantly lower, suggesting a decrease in red blood cells deformability. A relation between hemichrome-induced band 3 aggregation and …rheologic modifications of red blood cells was observed. Hemichrome binding to band 3 seems likely to be an important event leading to membrane damages and, hence, responsible for erythrocytes removal from blood circulation by the phagocytic system. Density gradient separation of erythrocyte subpopulation was performed in a selected case and the same biochemical, redox status and rheologic parameters were determined. The oldest cells have no detectable hemichromes and their deformability is better than that of cells containing a relevant amount of hemichromes. Show more

Keywords: thalassemia, hemichromes, oxidative damage, RBC viscosity, RBC deformability

DOI: 10.3233/CH-1996-16607

Citation: Clinical Hemorheology and Microcirculation, vol. 16, no. 6, pp. 789-797, 1996

Article Type: Abstract

DOI: 10.3233/CH-1996-16608

Citation: Clinical Hemorheology and Microcirculation, vol. 16, no. 6, pp. 799-811, 1996

Authors: Adams, R.A. | Jones, J.G. | Evans, S.-A. | Cook, A.M.

Article Type: Letter

DOI: 10.3233/CH-1996-16609

Citation: Clinical Hemorheology and Microcirculation, vol. 16, no. 6, pp. 813-814, 1996

Article Type: Other

DOI: 10.3233/CH-1996-16610

Citation: Clinical Hemorheology and Microcirculation, vol. 16, no. 6, pp. 815-841, 1996