blood physiology blood grouping blood transfusion

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2. CONTENTS INTRODUCTION PROPERTIES OF BLOOD FUNCTIONS OF BLOOD FORMATION OF BLOOD COMPOSTION OF BLOODPlasmaRed Blood CellsWhite Blood CellsPlatelets 3. HEMOSTASIS BLOOD GROUPING BLOOD TRANSFUSION ROLE OF PUBLIC HEALTH DENTIST CONCLUSION REFERENCES 4. INTRODUCTION Blood is a complex, living tissue that contains many cell typesand proteins. A transporter, regulator, and defender, bloodcourses through the body carrying out many importantfunctions. Blood, fluid pumped by the heart that circulates throughout thebody via the arteries, veins, and capillaries . An adult male ofaverage size normally has about 6 quarts (5.6 litres) of blood.The blood carries oxygen and nutrients to the body tissues andremoves carbon dioxide and other wastes. The colourless fluidof the blood, or plasma, carries the red and white blood cells,platelets, waste products, and various other cells andsubstances. 5. Blood is the only tissue that flows throughout our body. Thisred liquid carries oxygen and nutrients to all parts of the bodyand waste products back to our lungs, kidneys and liver fordisposal. It is also an essential part of our immune system,crucial to fluid and temperature balance, a hydraulic fluid forcertain functions and a highway for hormonal messages. Blood is a wonderful tissue may be the easiest to transplant(transfuse). 6. PROPERTIES OF BLOODColor Oxygen-rich blood is scarlet red bright crimson.(arterialblood) Oxygen-poor blood is purple red. (Venous blood) Red color comes from the several million red cells, presentin it.Volume In a normal adult is 5 ltrs in women & 5.5 ltrs in men andrepresents about 8% of total body weight.Reaction and pH Blood is slightly alkaline and its pH in normal conditions is7.4. 7. Specific gravity total blood :1.052 to 1.061 blood cells : 1.092 to 1.101 plasma : 1.022 to 1.026Viscosity Blood is 5 times more viscous than water mainly due to redblood cells and plasma proteins.Temperature 38 c or 100.4 F 8. FUNCTIONS OF BLOODNUTRIENT FUNCTION.RESPIRATORY FUNCTION.EXCRETORY FUNCTION.TRANSPORT OF HORMONES ANDENZYMES.REGULATION OF WATER BALANCE.REGULATION OF ACID BASEBALANCE.REGULATIONOF BODY TEMPERATURESTORAGE FUNCTION.DEFENCIVE FUNCTION. 9. 1. NUTRIENT FUNCTIONNutritive substances like glucose, amino acids, lipids andvitamins derived from digested food are absorbed fromgastrointestinal tract and carried by blood to different parts ofthe body for growth and for production of energy.2. RESPIRATORY FUNCTIONTransport of respiratory gases is done by the blood. It carriesoxygen from alveoli of lungs to different tissues and carbondioxide from tissues to alveoli. 10. 3. EXCRETORY FUNCTIONWaste products formed during various metabolic activitiesfromthe tissues are removed by blood and carried to the excretoryorgans like kidney, skin, liver, etc.4. TRANSPORT OF HORMONES AND ENZYMESThe hormones and some of the enzymes are carried by bloodto different parts of the body from the source of secretion. 11. 5. REGULATION OF WATER BALANCEWater content of the blood is freely interchangeable with interstitialfluid. This helps in the regulation of water content of the body.6. REGULATION OF ACID BASE BALANCEThe plasma proteins and hemoglobin act as buffers and help inregulation of acid base balance. 12. 7. REGULATIONOF BODY TEMPERATUREBecause of the high specific heat of blood, it is responsible formaintaining the thermoregulatory mechanism in the body, i.e.the balance between heat loss and heat gain in the body.8. STORAGE FUNCTIONWater and some important substances like proteins, glucose,sodium and potassium are constantly required by the tissues.Blood serves as a readymade source for these substances. And,these substances are taken from blood during the conditionslike starvation, fluid loss, electrolyte 13. 8.DEFENCIVE FUNCTION.Immunological functions, including circulation of white bloodcells, and detection of foreign material by antibodies. 14. FORMATION OF BLOOD In foetus - bone marrow,liver & spleen In adults- bone marrow. In children, blood cells are actively produced in marrowcavities of all the bones 75% of the cells - white blood cell producing myeloid series &25% are maturing red cells Bone marrow contains pluripotent stem cells that differentiateinto progenitor cells that in turn differentiate into variousdifferentiated types of blood cells. 15. BONE MARROW The bone marrow is present in the bone cavities. It can be considered as one of the largest organs in the body,and also one of the most active. In children, blood cells are produced in the marrow cavities ofall the bones. Gradually, it gets replaced by fat (yellow marrow). In the adult blood cells are produced in the bone marrow ofselected bones (e.g. backbone vertebral column, ribs, bonesof the skull, etc.) 16. HEMATOPOIESISHematopoiesis is the process which includesorigin, development and maturation of all theblood cells.Hematopoiesis is the process which includesorigin, development and maturation of all theblood cells. 17. STEMCELLS The stem cells are the primitive cells in the bone marrow,which give rise to the blood cells. As the stem cells can giverise to different types of blood cells, these are calledpluripotent hemopoietic stem cells (PHSC). In the earlierstages, the stem cells are not designed to form a particular typeof blood cell. And it is also not possible to determine the bloodcell to be developed from these stem cells. 18. So at this stage, the cells are called uncommitted pluripotenthemopoietic stem cells (Uncommitted PHSC). When thecells are designed to form a particular type of blood cell, thestem cells are called committed pluripotent hemopoieticstem cells (Committed PHSC). The committed stem cells areof two types namely:1. Lymphoid stem cells (LSC) which give rise to lymphocytes.2. Colony forming blastocytes, which give rise to the blood cellsother than lymphocytes. 19. When grown in cultures, these cells form colonies hence thename colony forming blastocytes. There are different units ofcolony forming cells as follows:a. Colony Forming Unit-Erythrocytes (CFU-E).The stem cells ofthis unit develop into erythrocytes.b. Colony Forming Unit-Granulocytes/ Monocytes (CFU-GM).These cells give rise to granulocytes (neutrophils, basophilsand eosinophils) or Monocytes.c. Colony Forming Unit-Megakaryocytes (CFU-M).From these,platelets are developed. 20. BLOOD CELLS - TYPICAL COUNT Total Erythrocytes = 5,000,000,000 cells/ml blood RBC count = 5,000,000/mm3 Total leukocytes = 7,000,000 cells/ml blood WBC count = 7,000/mm3 Differential White Blood Cell Count(% Distribution of Types of Leukocytes)Polymorphonuclear granulocytes Mononuclear agranulocytesNeutrophils 60-70% Lymphocytes 25-33%Eosinophils 1-4% Monocytes 2-6%Basophils 0.25-0.5% Total Platelets = 250,000,000/ml blood Platelet count = 250,000/mm3 21. UNCOMMITTED PLEURIPOTENT HAEMOPOIETIC STEM CELLCOMMITTED PLEURIPOTENT HAEMOPOIETIC STEM CELLMLYMPHOID STEM CELLCOLONY FORMING BLASTOCYTEC F U-E CF U-GM C F U-MGRANULOCYTES MEGAKARYOCYTEL R N B E P 22. ERYTHROPOIESISErythropoiesis is the process by which the origin,develop-ment and maturation of erythrocytes occur. 23. Site of erythropoiesis in fetal lifeDuring embryonic life, erythropoiesis occurs in three stages.i) Mesoblastic stage: During the first two months ofintrauterine life, the primitive red blood cells are produced frommesenchyme of yolk sac.ii) Hepatic stage: From third month of intrauterine life,liver is the main organ that produces red blood cells. Someerythrocytes are also produced from spleen and lymphoid organs.iii) Myeloid stage: During the last three months of intrauterine life, the red blood cells are produced from red bonemarrow and liver. 24. In post natal life and In adults1. Up to age of 5 to 6 years: The red blood cells are produced inred bone marrow of all bones.2. From 6th year up to 20th year: The red blood cells areproduced by red bone marrow of long bones and all themembranous (flat) bones.3. After the age of 20 years: The red blood cells are producedfrom all membranous bones like vertebra, sternum, ribs, scapula,iliac bones and skull bones and from the ends of long bones.After 20 years of age, the shaft of the long bones becomes yellowbone marrow because of fat deposition and lose theerythropoietic function.During disorders of bone, the RBCs are produced in spleen. 25. Stages of ErythropoiesisCELL DIAMETER NUCLEUS CYTOPLASMCELL DIAMETER NUCLEUS CYTOPLASM15-20 m Big & strongly Very scanty & basophilic15-20 m Big & strongly Very scanty & basophilicbasophilic No Hb.basophilic No Hb.11-16 m Smaller Scanty & basophilic.11-16 m Smaller Scanty & basophilic.No Hb.No Hb.10-12 m Smaller & Hb starts to appear,10-12 m Smaller & Hb starts to appear,Denser cytoplasm polychromatic.Denser cytoplasm polychromatic.8-10 m Ink spot Plentiful, eosinophilic.8-10 m Ink spot Plentiful, eosinophilic.nucleus increase in Hb.nucleus increase in Hb.8-10 m Absent Some RNA still present.8-10 m Absent Some RNA still present.7.5 m Absent Hb++.7.5 m Absent Hb++. 26. Factors Affecting Erythropoiesis General factors Erythropoietin Thyroxine Hemopoietic growth factors Vitamins Maturation factors Vitamin B12 Intrinsic Factor of Castle Folic Acid Factors necessary for Hb formation First class proteins & amino acids Iron Copper Co ,Ni vitamins 27. LEUKOPOIESISLeukopoiesis is the development and maturation of leukocytes. 28. STEM CELLSThe committed pluripotent stem cell gives rise to colony formingunit and lymphoid stem cell. COLONY FORMING UNIT Different colony forming units are:1. Colony forming unit-Erythrocytes (CFU-E)2. Colony forming unit-Granulocytes and Monocytes (CFU-GM)3. Colony forming unit-Megakaryocytes (CFU-M) DEVELOPMENT OF GRANULOCYTES Granulocytes are formed in bone marrow. The colony formingunit-granulocyte-monocyte (CFU-GM) gives origin to