„Secret fluids” - biological fluids overview, modelling, problems Anna Kucaba-Piętal Rzeszów University of Technology, Poland School of Engineering, University of Liverpool Liverpool L69 3GH, UK , May 13th 2013 1 Contents Overview of biological fluids, contents, modelling, problem formulation • Fundamental • biofluid • rheology • Blood • rheological parameters of blood • factors which effect on blood viscosity • diaseses • Synovial fluid • rheological parameters of s.f • factors which effect on s. f. viscosity • diaseses • Plasma and lymph as Newtonian fluid • Conclusion 2 Aim of Lectures Questions: What influences the change of rheological properties of biological fluids and what are the consequences? Why is it important to predict rheological parameters of biofluid? Answers: Due to the formulation bioflow equations To maintain nonbiological fluids that has rheological properties comparble to real biofluid To use it in diagnostics of clinical disorders 3 4 Body fluids • Total amount of fluid in the human body is approximately 70% of body weight • Body fluid has been divided into two compartments – – Intracellular fluid (ICF) – Extracellular fluid • Outside the cells • 45% of total body water 40 Percentage of Body Weight • Inside the cells • 55% of total body water 35 30 25 Intracellular 20 Extracellular 15 Interstitial 10 Plasma 5 0 Body1Fluids 5 Body fluid compartments Extracellular fluid includes: • Interstitial fluid » Present between the cells » Approximately 80% of ECF • Plasma » Present in blood » Approximately 20% of ECF • Also includes » Lymph » synovial fluid » aqueous humor » cerebrospinal fluid » vitreous body » endolymph » perilymph » pleural, pericardial and peritoneal fluids 6 Body fluid compartments 7 Body fluid compartments 8 Barriers separate ICF, interstitial fluid and plasma • Plasma membrane • Separates ICF from surrounding interstitial fluid • Blood vessel wall • Separate interstitial fluid from plasma 9 Composition of body fluids Organic substances Glucose Amino acids Fatty acids Hormones Enzymes Inorganic substances Sodium Potassium Calcium Magnesium Chloride Phophate Sulphate 10 Difference • Most abundant cation - Na+, • Most abundant cation - K+ – muscle contraction – Impulse transmission – fluid and electrolyte balance – – – – Resting membrane potential Action potentials Maintains intracellular volume Regulation of pH • Most abundant anion - Cl– Regulates osmotic pressure – Forms HCl in gastric acid • Anion are proteins and phosphates (HPO42-) Na+ /K+ pumps play major role in keeping K+ high inside cells and Na+ high outside cell 11 Control of body fluid volume (Homeostasis) • In health the volume and composition of various body fluid compartments are maintained within physiological limits even in face of wide variations in intake of water and solutes . 12 Body fluids • • • • • • • • • • • • • • • Amniotic fluid Aqueous humour and vitreous humour Bile Blood Breast milk Cerebrospinal fluid Cerumen (earwax) Chyle Chyme Endolymph and perilymph Feces - see diarrhea Female ejaculate Gastric acid Gastric juice Lymph • • • • • • • • • • • • • • • • Mucus (including nasal drainage and phlegm) Pericardial fluid Peritoneal fluid Pleural fluid Pus Rheum Saliva Sebum (skin oil) Semen Sputum Sweat Synovial fluid Tears Vaginal secretion Vomit Urine 13 Specialized fluids of the body • • • • • • • Lymph Milk Cerebrospinal fluid Amniotic fluid Aqueous humor Sweat Tears 14 Transport problems Microscopic level • Transport Mechanisms • Membrane Transport • Intracellular membrane transport • ICF-ECF Exchange • ISF-Plasma Exchange • Capillary Pressures Macroscopic level • Blood Flow CFD simulation • synovial fluid 15 Navier-Stokes equations • Wstawie pozniej 16 Rheological parameters, a constitutive equation • The viscosity and elasticity determine the pressure required to produce bioflows. • Viscosity is an assessment of the rate of energy dissipation • Elasticity is an assessment of the elastic storage of energy • How is relations between shear stress and deformation? 17 Body fluid percentages 18 Rheology as an interdisciplinary science Physics Chemistry Rheology (of Liquids) Mechanics of Continuum Technology/ Engineering 19 Viscosity Viscosity = F(S,T,p,s,t, V) S- physico-chemical properties of substances, T-temperature, p- pressure, s-velocity of shear, ttime, V-voltage dU τμ μγ dy 20 Models NEWTONIAN FLUID F y u(y) NON-NEWTONIAN FLUID . t f(g) 21 21 Blood Blood is a concentrated suspension of Red Blood Cells; outside the range of dilute suspension Particles change their shape in response to the fluid forces The nature of RBC membrane and its deformation stress/strain is much less established RBC tends to form agregates known as rouleaux 22 Blood - components Constituents of Blood Plasma proteins Red blood cells White blood cells Water Electrolytes Organic nutrients Organic wastes Platelets % 3.2 – 4.4 40 – 54 0.03 - 0.05 42 –58 < 0.001 < 0.001 < 0.001 ~ 0.1 23 Blood – formed elements TYPES OF LEUKOCYTES PLATELETS RBCs 24 Physical properties of blood PROPERTY Density (g/cm3) RANGE 1.050-1.064 Viscosity (cP) 2.18-3.59 pH 7.35-7.45 Factors affecting the blood rheology: a) hematocrit b) deformation and agregation of red blood cells c) biochemical properties of plasma d) temperature e) the geometry and flow parameters 25 Plasma Plasma is the straw-colored liquid in which the blood cells are suspended. Composition of blood plasma: Component Water Proteins Salts Lipids Glucose (blood sugar) Percent ~92 6–8 0.8 0.6 0.1 26 Plasma • Water : 90% • Solids: 10% • organic constituents: proteins, lipids, carbohydrates , hormones, enzymes, Ketone bodies , and other organic compounds. Inorganic compounds: Na, K Ca,Cl,and CO2. 27 Comparison of Newtonian plasma and blood viscosity 28 Lymph • Clear and colorless fluid • 96% water and 4% solids • Solids – – Proteins • 2-6% of solids • albumin, globulin, fibrinogen, prothrombin, clotting factors, antibodies, enzymes – Lipids • 5-15% • Chylomicrons • Lipoproteins – Carbohydrates • Glucose mainly – NPN • Urea and creatinine – Electrolytes • Sodium, calcium, potassium, chloride, bicarbonates 29 Functions of lymph • Return protein from tissue spaces into blood • Redistribution of fluid • Removal of bacteria, toxins and other foreign bodies from tissues • Maintain structural and functional integrity of tissue • Route for intestinal fat absorption • Transport lymphocytes 30 Lymphatic fluid • What is it? It is a fluid that resembles plasma but with a much lower concentration of suspended proteins • Functions? Transports hormones, nutrients, and waste products from peripheral tissues to the general circulation Returns fluid and solute from peripheral tissues to the blood Maintains blood volume and eliminates local variations in the composition of the interstitial fluid 31 Newtonian behavior Newtonian fluid: constant viscosity at all shear rates at a constant pressure and temperature. Relationship between shear stress and shear rate is linear. 32 Synovial fluid 33 Synovial fluid Contents Dry matter Density(20oC) pH value 0,133,5 1,00811,015 7,27,4 viscosity (20oC) water, g/kg hyaluronic acid (HA ) 960988 The content of dry matter g/kg 1240 Albumins, globulins g/l Phospholipids, glycoprotein's 10,721,3 10,2 0,5 Mucyns, g/l 0,681,35 Glucoses, g/l jak w surowicy krwi Urynial Acid, mg/l 73,4 2-3% 34 Functions • Minimise the friction between during bones movement or weight bearing • Provides nutrition for cartilage. • 0.15-3.5ml 35 Synovial fluid Main Factors affecting the rheological properties: a) Hyaluronic Acid concentation c) Molecular weigh of Hyaluronic Acid d) Temperature Sodium Hyaluronate, Hyaluronan • Made up of repeating glucuronic acid and N-acetylglucosamine subunits • High molecular weight: 0.2 to 10 million Dalton • Major component of synovial fluid • Exhibits viscoelastic properties 36 Perspectives • Pathophysiological significance of biofluid rheology • Develop an understanding of how the micro- and nanostructure of blood influences its rheology • Explore to use of rheological parameters in diagnostics and menagement of clinical disorders and inoptimisation of blood processing • Explore new methods of measurement suited for clinical application • Maintain new type apparatus for such measurements 37 Thank you 38