Clinical Hemorheology

1. Introduction: On the way to modern clinical hemorheology.- 2. Biophysics.- 2.1. Basic concepts.- 2.1.1. Rheology.- 2.1.2. Stress, strain and strain rate.- 2.1.3. Elastic solid and viscous fluid.- 2.1.4. Classification of viscous liquids.- 2.1.5. Viscoelasticity.- 2.1.6. Surface rheology.- 2.2. Viscometry.- 2.2.1. Laminar and turbulent flow.- 2.2.2. Temperature control.- 2.2.3. Steady-flow viscometers.- 2.2.4. Tube viscometers.- 2.2.5. Rotational viscometers.- 2.2.6. Oscillatory flow methods.- 2.3. Other techniques quantifying blood rheology.- 2.3.1. Optical aggregometry.- 2.3.2. Blood filtration.- 2.4. Rheology of normal blood.- 2.4.1. Shear dependence.- 2.4.2. Plasma viscosity.- 2.4.3. Effect of hematocrit.- 2.5. Blood sampling and handling in hemorheological tests.- 2.5.1. Postural changes.- 2.5.2. Venous occlusion.- 2.5.3. Diurnal, seasonal and climatic variations.- 2.5.4. Anticoagulation and storage.- 2.6. Clinical interpretation of hemorheological data.- 2.6.1. Plasma viscosity.- 2.6.2. Blood viscosity.- 2.6.3. Blood filtration.- 2.6.4. Optical aggregometry and erythrocyte sedimentation rate.- 2.7. References.- 3. Rheology of blood cells.- 3.1. Introduction.- 3.2. Dynamic deformability of blood cells.- 3.2.1. Blood cells deformability: "extrinsic factors".- 3.2.2. Red blood cell deformability: "intrinsic factors".- 3.2.3. White blood cell deformability: "intrinsic factors".- 3.3. Rheological implications of blood cell deformabilities.- 3.4. Blood cell aggregation - disaggregation and interaction with vascular endothelium.- 3.4.1. Red blood cell aggregation: mechanisms.- 3.4.2. Red blood cell aggregation: measurement.- 3.4.3. Adhesion of blood cells to vessel walls.- 3.5. Acknowledgements.- 3.6. References.- 4. Structural, hemodynamic and rheological characteristics of blood flow in the circulation.- 4.1. Introduction.- 4.2. Structural and hemodynamic characteristics of the vascular system.- 4.3. Functional compartments within the vascular system.- 4.3.1. The high pressure conduit vessels.- 4.3.2. The control compartment.- 4.3.3. The exchange compartment.- 4.3.4. The low pressure compartment.- 4.4. Blood cell rheology in the circulation.- 4.4.1. Bulk flow regime I.- 4.4.2. Transition zone IIa.- 4.4.2.1. Fahraeus effect.- 4.4.2.2. Fahraeus-Lindqvist effect.- 4.4.3. Transition zone IIb.- 4.4.4. Single file flow regime III.- 4.5. Summary and conclusions.- 4.6. References.- 5. Physiological and pathophysiological significance of hemorheology.- 5.1. The role of hemorheology in circulatory physiology.- 5.1.1. Vascular hindrance and blood viscosity as determinants of resistance.- 5.1.2. Fundamental determinants of blood viscosity.- 5.1.3. Blood rheology in relation to circulation in vivo.- 5.1.4. Influence of blood rheology on oxygen transport.- 5.1.5. Influence of leukocytes on blood flow in the microcirculation.- 5.1.6. Modeling of microcirculatory networks.- 5.2. Circulatory consequences of pathological alterations in blood rheology.- 5.2.1. Hemorheological abnormalities in hematological disorders.- 5.2.2. Hemorheological abnormalities in cardiovascular disease.- 5.2.3. Compensatory adjustments to pathological alteration in blood rheology.- 5.3. Summary and conclusions.- References.- 6. Cardiovascular diseases.- 6.1. Introduction.- 6.2. Myocardial ischemia.- 6.2.1. Epidemiological evidence.- 6.2.2. Established myocardial ischemia.- 6.2.3. Changes associated with acute myocardial ischemia.- 6.2.4. Therapeutic implications.- 6.3. Hypertension.- 6.4. Cerebral ischemia.- 6.4.1. Physiological and epidemiological evidence.- 6.4.2. Role in the evolution of cerebral infarction.- 6.4.3. Therapeutic implications.- 6.5. Ischemia of the leg.- 6.5.1. Pathological role.- 6.5.2. Clinical significance.- 6.5.3. Therapeutic implications.- 6.6. Raynaud's phenomenon.- 6.6.1. Pathological role.- 6.6.2. Therapeutic implications.- 6.7. Conclusions.- 6.8. References.- 7. Thrombosis and hemorheology.- 7.1. Introduction.- 7.1.1. Sites of thrombosis.- 7.1.2. Structure of thrombi.- 7.2. Rheology and platelets.- 7.2.1. Platelets and hemostasis.- 7.2.2. Effects of red cells on platelets in hemostasis.- 7.2.3. Platelet adhesion.- 7.2.4. Platelet aggregation and secretion.- 7.2.5. Effects of red cells on platelet aggregation.- 7.2.6. Effects of fibrinogen on platelet behavior.- 7.3. Rheology, coagulation and fibrinolysis.- 7.4. Venous thromboembolism.- 7.4.1. Flow conditions and leg vein thrombosis.- 7.4.2. Hematocrit and leg vein thrombosis.- 7.4.3. Fibrinogen and leg vein thrombosis.- 7.4.4. Retinal vein thrombosis.- 7.5. Arterial thromboembolism.- 7.5.1. Cardiac thromboembolism.- 7.5.2. Arterial thrombosis and atherogenesis.- 7.5.3. Occlusive arterial thrombi on atherosclerotic plaques.- 7.5.4. Outcome of occlusive arterial thrombosis.- 7.6. Thrombosis of arterial shunts and grafts.- 7.7. Microvascular thrombosis.- 7.7.1. Disseminated intravascular coagulation.- 7.7.2. Leukostatis.- 7.8. References.- 8. Hemorheology and blood diseases.- 8.1. Introduction.- 8.2. The pathophysiology of blood hyperviscosity.- 8.3. The syndrome of polycythemic hyperviscosity.- 8.3.1. Erythrocytosis.- 8.3.2. Hyperleukocytic leukemias.- 8.4. The syndrome of sclerocythemic hyperviscosity.- 8.4.1. Sickle cell disease.- 8.4.2. Hemolytic anemias.- 8.5. The syndrome of plasmatic hyperviscosity.- 8.5.1. Paraprotein diseases.- 8.5.2. Hematological stress syndrom.- 8.6. Summary and conclusions 249 References.- 9. Obstetrics, neonatology and gynaecology.- 9.1. Why rheology in obstetrics, gynaecology and neonatology?.- 9.2. Maternal rheology in normal pregnancy.- 9.3. Normal fetal hemorheology.- 9.4. Pathological pregnancy.- 9.4.1. Maternal smoking in pregnancy.- 9.4.2. Pre-eclampsia.- 9.4.3. Hemorheological therapy in pre-eclampsia.- 9.4.4. Diabetes mellitus in pregnancy.- 9.5. Rheology in the neonate.- 9.6. Treatment of neonatal hyperviscosity.- 9.7. Rheological sequelae of oral contraception.- 9.8. References.- 10. Diabetes.- 10.1. Introduction.- 10.2. Diabetes and its complications.- 10.3. Relevance of blood rheology in diabetes.- 10.4. Macrorheology of blood in diabetes.- 10.4.1. Whole blood viscosity.- 10.4.2. Plasma and serum viscosity.- 10.5. Microrheology of blood in diabetes.- 10.5.1. Red cell deformability.- 10.5.2. Red cell aggregation.- 10.5.3. Red cell adhesion.- 10.6. Implications.- 10.6.1. Whole blood viscosity and large vessel disease.- 10.6.2. Red cell deformability, plasma viscosity and microangiopathy.- 10.6.3. Blood rheology relation to other etiological candidates of diabetic complications.- 10.7. References.- 11. Other syndromes associated with impaired blood flow and rheology.- 11.1. Introduction.- 11.2. Shock.- 11.2.1. Traumatic shock.- 11.2.2. Hemorrhagic shock.- 11.2.3. Burns.- 11.2.4. Septic shock.- 11.2.5. Anaphylactic shock.- 11.3. Surgery and anesthesia.- 11.4. Rheumatic disease.- 11.5. Renal disease.- 11.5.1. Nephrotic syndrome.- 11.5.2. Dialysis.- 11.6. Neoplastic disease.- 11.7. Miscellaneous.- 11.8. Summary and conclusion.- 11.9. References.- 12. Hemorheological treatment.- 12.1. Introduction.- 12.2. Hemodilution 330 12.2.1. Forms of hemodilution.- 12.2.2. Mode of action.- 12.2.3. Clinical evidence.- 12.3. Apheresis.- 12.3.1. Plasma exchange.- 12.3.2. Erythrapheresis.- 12.3.3. Leukopheresis.- 12.4. Plasma substitutes.- 12.4.1. Albumin.- 12.4.2. Dextrans.- 12.4.3. Hydroxyethyl starch (HES).- 12.4.4. Gelatins.- 12.5. Defibrinogenation.- 12.5.1. Mode of action.- 12.5.2. Guidelines for medication.- 12.5.3. Clinical evidence.- 12.6. Oral drugs.- 12.6.1. Oral drugs decreasing plasma viscosity.- 12.6.2. Oral drugs to normalize red cell deformability.- 12.6.3. Evaluation.- 12.6.4. Drugs with "hemorheological side-effects".- 12.7. Non-pharmacological approach.- 12.7.1. Physical fitness.- 12.7.2. Physical therapy.- 12.7.3. Diet.- 12.8. Conclusions.- 12.9. References.- 13. Summary, Conclusions and Perspectives.- 13.1. Brief summary.- 13.2. Conclusions.- 13.3. Perspectives.