1. THE PHYSIOLOGY OF BLOODByDr.M.ANTHONY DAVID, MD.NOMAD:2005: BP: 1INTROVERVIEW

2. WHAT IS BLOOD? IT IS A LIQUID CONNECTIVE TISSUE IN AN AVERAGE 70 Kg MAN: 100 Trillion cells. Of which 25 trillions are Red Blood Cells! The average blood volume is 5 6 lts. It is roughly 7% of the total body weight. NOMAD:2005: BP: 2 INTROVERVIEW 3. HEMATOLOGY: THE STUDY OF BLOOD MADE POSSIBLE BY MICROSCOPYNOMAD:2005: BP:3INTROVERVIEW 4. THE COMPOSITION OF PLASMA The Liquid: Plasma: Water, the solvent The solute: Proteins: Albumin Globulins Fibrinogen Electrolytes: Na+ K+ Ca++ Organic molecules Urea Glucose Lipids NOMAD:2005: BP:4 INTROVERVIEW 5. THE FORMED ELEMENT: CELLS BLOOD CELLSERYTHROCYTES LEUCOCYTES THROMBOCYTESNOMAD:2005: BP:5INTROVERVIEW 6. BLOOD : COMPOSITION NOMAD:2005: BP: 6 INTROVERVIEW 7. FUNCTIONS OF BLOOD NUTRITIVE RESPIRATORY EXCRETORY BODY DEFENCE: IMMUNITY TRANSPORT: HORMONES VITAMINS DRUGSNOMAD:2005: BP: 7INTROVERVIEW 8. BLOOD : TRANSPORTINGHORMONE MOLECULES NOMAD:2005: BP: 8 INTROVERVIEW 9. OXYGEN & CO2 TRANSPORT NOMAD:2005: BP: 9 INTROVERVIEW 10. FUNCTIONS OF BLOOD HOMEOSTATIC FUNCTION:ACID BASE BALANCE.ELECTROLYTE BALANCE.HEMOSTASIS.THERMOREGULATION.NOMAD:2005: BP: 10INTROVERVIEW 11. BLOOD VOLUMENOMAD:2005: BP: 11INTROVERVIEW 12. WHAT IS BLOOD VOLUME? The total amount of blood incirculation plus the amount ofblood in the reservoirsconstitutes the Blood Volume The average adult 70 kg man hasa blood volume of 5 to 6 litres.NOMAD:2005: BP:12INTROVERVIEW 13. EXPRESSION OF BLOOD VOLUME Usually Blood Volume is expressedin liters. It can also be expressed in relationto body weight. It is 7% Body Weight Another way to express it is interms of Body Surface Area. Whole Blood : 2.8 Lts/M2 Plasma : 1.5 Lts/M2NOMAD:2005: BP:13INTROVERVIEW 14. METHODS OF MEASURING BLOOD VOLUME IN HUMANS: ONLY INDIRECT METHODS DYE DILUTION TECHNIQUE: PRINCIPLE: Injection of a known volume of non toxic substance into the circulation. Measuring the dilution of this injected dye after some time. This gives us the Plasma volume. NOMAD:2005: BP: 14 INTROVERVIEW 15. DYE DILUTION TECHNIQUEV1 = VOLUMEC1 = CONCENTRATION OF DYEV2 = VOLUME C2 = CONC. OF DYEV1 X C1 = V 2 X C2ORV2 = V1 X C1 = Amount of Dye injected C2Conc. Of NOMAD:2005: BP: the Plasmathe dye in 15 INTROVERVIEW 16. HEMATOCRIT (PCV) The volume of erythrocytes inthe whole blood expressed inpercentage is the Hematocrit. This is also called as Packed CellVolume or PCV. This is determined by theWintrobes tube, using aCentrifuge. NOMAD:2005: BP: 16 INTROVERVIEW 17. HEMATOCRIT A mixture of blood and double oxalate(K NH4) is taken upto 100 mark in theWintrobes tube. The tube is placed in the centrifuge. It is rotated at 3,000 rpm for 30minutes. The Hematocrit is then read off thetube. Blood Volume = Plasma Volume X 100 100 - PCV NOMAD:2005: BP:17 INTROVERVIEW 18. HEMATOCRIT NOMAD:2005: BP: 18 INTROVERVIEW 19. BLOOD VOLUME: PHYSIOLOGICAL VARIATIONS AGE PREGNANCY SEX EXERCISE TEMPERATURE POSTURE BODY WEIGHT HYPOXIA BODYSURFACE AREA EMOTIONSNOMAD:2005: BP:19INTROVERVIEW 20. BLOOD VOLUME & AGEAGE BLOOD VOLUME in LitersAT BIRTH0.36 Months0.5 1 year 0.72yrs 6 months 1.0 4 years1.3 7 years1.710 years 2.5(Girls); 3.2 (Boys)ADULTS 5 (Men) 4.5 (Women)NOMAD:2005: BP: 20INTROVERVIEW 21. BLOOD VOLUME: PHYSIOLOGICAL VARIATIONS1. SEX: Males have moreblood volume thanfemales.2. TEMPERATURE: Acute exposure tocold causes reductionin blood volume dueto Plasma water lossto tissues. NOMAD:2005: BP: 21 INTROVERVIEW 22. BLOOD VOLUME: PHYSIOLOGICALVARIATIONS3. BODY WEIGHT: It is usually 7% of the Body Weight.4. BODY SURFACE AREA: 2.8 Lts/Square Meters of BSA NOMAD:2005: BP:22 INTROVERVIEW 23. BLOOD VOLUME: PHYSIOLOGICALVARIATIONS5. PREGNANCY: Increases by 20 30% due to mass of fetus.6. EXERCISE: Vigorous exercise causes an increase.7. POSTURE: Changing from lying down to erect.NOMAD:2005: BP: 23INTROVERVIEW 24. BLOOD VOLUME: PHYSIOLOGICALVARIATIONS 8. HYPOXIA: Seen in Highaltitudes. Erythrocytes So Blood volume. 9. EMOTIONS: Excitement causes anincrease in the Bloodvolume. 24 NOMAD:2005: BP: INTROVERVIEW 25. BLOOD VOLUME: PATHOLOGICALVARIATIONS : hypovolemia1. BLOOD LOSS:2. SHOCK: Crushing Injury Cardiogenic Neurogenic Psychogenic.NOMAD:2005: BP:25INTROVERVIEW 26. HYPOVOLEMIA: CAUSES3. HEMOLYSIS: Mismatched transfusion Snake bite Black water fever Hemorrhagic Plagues/Dengue Measles NOMAD:2005: BP: 26 INTROVERVIEW 27. HYPOVOLEMIA: CAUSES4. DEHYDRATION: Diarrhoea Cholera Gastroenteritis Burns Hyperemesis.NOMAD:2005: BP: 27INTROVERVIEW 28. HYPOVOLEMIA: CAUSES (contd)5. ANEMIA: Decreased RBC volume Plasma may increase.6. OBESITY: Blood volume per body weight decreasesthough Blood volume per BSA may be normal.7. HYPOTHYROIDISM (MYXEDEMA): Decrease in Blood volume.8. ACUTE COLD: Decreases blood volume. NOMAD:2005: BP: 28 INTROVERVIEW 29. TREATMENT FOR BLOOD LOSS TRANSFUSION OF WHOLEBLOOD OF THE SAME BLOODGROUP & TYPE. INFUSION OF PLASMA INFUSION OF DEXTRAN ORNORMAL SALINE.NOMAD:2005: BP: 29INTROVERVIEW 30. NOMAD:2005: BP: 30INTROVERVIEW 31. HEMOPOIESIS &ERYTHROPOIESISNOMAD:2005: BP: 31INTROVERVIEW 32. HEMOPOIESIS: INTRO Hemo: Referring to blood cells Poiesis: The development or productionof The word Hemopoiesis refers to theproduction & development of all theblood cells: Erythrocytes: Erythropoiesis Leucocytes: Leucopoiesis Thrombocytes: Thrombopoiesis. Begins in the 20th week of life in thefetus & continues in the red bonemarrow till death. BP: NOMAD:2005: INTROVERVIEW 32 33. STEM CELL THEORY All blood cells are produced by thebone marrow. They come from a single class ofprimitive mother cells called as: PLURIPOTENT STEM CELLS. These cells give rise to blood cells of: Myeloid series: Cells arising mainly fromthe bone marrow. Lymphoid series: cells arising fromlymphoid tissues. NOMAD:2005: BP:33 INTROVERVIEW 34. PROGENITOR CELLS Committed stem cells lose their capacity forself-renewal. They become irreversibly committed. These cells are termed as Progenitor cells They are regulated by certain hormones orsubstances so that they can: Proliferate Undergo Maturation.NOMAD:2005: BP:34INTROVERVIEW 35. BLOOD CELLS: DEVELOPMENT PROGENITORCELLSLYMPHOID PROMEGAMYELOBLASTMONOBLASTCELLS NORMOBLAST KARYOBLASTLYMPHOCYTES ERYTHROCYTES THROMBOCYTESGRANULOCYTES MONOCYTES NOMAD:2005: BP: 35 INTROVERVIEW 36. ERYTHROPOIESIS: SITES INTRAUTERINE LIFE: INTRAVASCULAR PHASE: Upto 3rd month of Intra Uterine Life.Endothelial cells = = = RBCs HEPATIC PHASE: 3rd to 5th month IULLiver & SpleennRBCs from Mesenchymal cells. MYELOID PHASE: From 5th month of IUL onwards.NOMAD:2005: BP:36INTROVERVIEW 37. ERYTHROPOIESIS: SITES contd. POST NATAL LIFE: CHILDREN:Predominantly Red Bone Marrow of skeleton: Axial & Appendicular. ADULTS:Red Bone Marrow of Axial Skeleton. NOMAD:2005: BP: 37 INTROVERVIEW 38. ERYTHROPOIESISPROERYTHROBLAST BASOPHILICERYTHROBLASTPOLYCHROMATOPHILIC ERYTHROBLAST ORTHOCHROMATICERYTHROBLASTRETICULOCYTE NOMAD:2005: BP: 38 INTROVERVIEWMATURE ERYTHROCYTES 39. FACTORS REGULATINGERYTHROPOIESIS SINGLE MOST IMPORTANT REGULATOR: TISSUE OXYGENATION BURST PROMOTING ACTIVITY ERYTHROPOIETIN IRON VITAMINS: Vitamin B12 Folic Acid MISCELLANEOUSNOMAD:2005: BP: 39INTROVERVIEW 40. ERYTHROPOIETINA hormone produced by the Kidney.Nowadays available as Synthetic EpoietinIncreases the number of:Nucleated precursors in the marrow.Reticulocytes & Mature Erythrocytes in the blood.NOMAD:2005: BP: 40INTROVERVIEW 41. VITAMINS B12: Cyanocobalamine & Folic Acid:Is also called Extrinsic Factor of Castle.Needs the Intrinsic Factor from theGastric juice for absorption from SmallIntestine.Deficiency causes Pernicious (When IF ismissing) or Megaloblastic Anemia.Stimulates ErythropoiesisIs found in meat & diary products. NOMAD:2005: BP:41 INTROVERVIEW 42. IRONEssential for the synthesis of Hemoglobin.Deficiency causes Microcytic, Hypochromic Anemia.Deficiency causes the commonest type of Anemia. NOMAD:2005: BP: 42 INTROVERVIEW 43. NOMAD:2005: BP: 43INTROVERVIEW