Blood Lecture 1 (RBC, WBC) PDF

BLOOD Lecture 01 Dr. Udeshika Yapa Bandara BSc. (Hons) Human Biology (USJP), PhD (UOC)  Learning Outcomes At the end of the session, you should be able to: understand physiology of red blood cells and white blood cells identify Blood groups and compati...

BLOOD Lecture 01 Dr. Udeshika Yapa Bandara BSc. (Hons) Human Biology (USJP), PhD (UOC)  Learning Outcomes At the end of the session, you should be able to: understand physiology of red blood cells and white blood cells identify Blood groups and compatibility during blood transfusion describe composition of body fluids describe blood transfusion and blood grouping The body fluid compartments in an adult male compared to an adult female  Composition of Blood 1. Cellular components (45 %) Red blood cells, RBCs (Erythrocytes) White blood cells , WBCs (Leukocytes) Platelets (Thrombocytes) 2. Plasma (55 %) 90% water, 8% protein (blood coagulation proteins, albumin, and the globulins), 1% inorganic salts, 0.5% lipids and 0.1% sugar, amino acids, antibodies, hormones, electrolytes, waste, and ions Same ionic composition as interstitial fluid  Haematopoiesis and Erythropoiesis Haematopoiesis - the maturation, development and formation of blood cells Location of haematopoiesis - red bone marrow (myeloid tissue) in blood sinusoids which connect with capillaries; mainly in axial skeleton and heads of femur & humerus haemocytoblast (stem cell) - the mitotic precursor to blood cells before differentiation differentiation - maturing cell becomes "committed" to being certain type blood cell Erythropoiesis - the maturation, development, and formation of RBCs (erythrocy tes) Thrombopoiesis – The production of platelets Haematopoiesis  Major Functions of Blood 1. Distribution & Transport a. oxygen from lungs to body cells b. carbon dioxide from body cells to lungs c. nutrients from GI tract to body cells d. nitrogenous wastes from body cells to kidneys e. hormones from glands to body cells 2. Regulation (maintenance of homeostasis) a. maintenance of normal body pH - blood proteins (albumin) & bicarbonate  Contd; b. maintenance of circulatory/interstitial fluid - electrolytes aid blood proteins (albumin) c. maintenance of temperature (blushed skin) 3. Protection a. platelets and proteins "seal" vessel damage b. protection from foreign material & infections - leukocytes, antibodies, complement proteins  Red Blood Cells (Erythrocytes/RBCs) Most abundant cell in the blood (4 million – 6 million per microliter of blood) Formed in the bone marrow Mature forms do NOT have a nucleus Shaped as biconcave disks 6-8 micrometers in diameter Life span - 120 days Haemoglobin (iron protein)is found in the RBC Haemoglobin carries oxygen from the lungs to the rest of the body and carbon dioxide binds to the RBC and is taken to the lungs to be exhaled. Polycythemia - condition results in an increased level of circulating RBCs Erythropenia - condition results in an decreased level of circulating RBCs  White Blood Cells (Leukocytes/ WBCs) Largest sized blood cells Lowest numbers in the blood (4,500 – 11,000 per microliter) Formed in the bone marrow and some in lymph glands Primary cells of the immune system Fights with diseases and foreign invaders Contain nuclei with DNA - the shape depends on type of cell Certain WBCs produce antibodies Life span - 24 hours to several years Size is 8-20 micrometers in diameter Five different types - Neutrophils, Eosinophils, Basophils, Lymphocytes, Monocytes Disease conditions - Leukocytosis – condition with an elevation in the total WBCs. Leucopenia – condition with a reduction in WBCs.  Platelets (Thrombocytes/ PLTs) Formed in the bone marrow Fragments from the cytoplasm of megakaryocytes Smallest of the blood cells 1-4 micrometers in diameter Shape can be round, oval, or appear spiky Life span of around 8-12 days 150,000 – 400,000 per microliter of blood Platelets stain bluish with reddish or purple granules Platelets , - Involved in the clotting process - Seal wounds and prevent blood loss - Help repair damaged vessels Thrombocytosis – condition developed with an elevated level of platelets Thrombocytopenia – condition developed with a decreased level of platelets  Blood transfusion Blood transfusion is a common, safe medical procedure in which healthy blood is given to an individual through an intravenous (IV) line Required during, Loss of blood during a surgery or injury, Less blood formation, anemia, sickle cell disease, a bleeding disorder (hemophilia, cancer) Types of blood transfusions - whole blood, red blood cells, platelets, and plasma Risks of blood transfusion Mismatched blood transfusion Immediate: - Haemolytic shock - Renal failure Delayed: - Jaundice Matched blood transfusion Immediate: - Circulatory overload - Hyperkalaemia - Hypocalcaemia Delayed: - Transmission of disease (HIV, Hepatitis B / C)  Blood grouping ABO blood group system First identified by Austrian immunologist Karl Landsteiner in 1901 Based on the inherited properties of erythrocytes Presence or absence of the antigens A and B (on the surface of the RBCs) Plasma contain anti-a or anti-b antigens or none.  Rh Blood group system Type of antigen Present in some people (Rh +) Absent in some (Rh-) Rh matching is essential before blood transfusion Erythroblastosis Faetalis (Haemolytic disease of the newborn) Type of anaemia The erythrocytes of a fetus are destroyed in a maternal immune reaction resulting from a blood group incompatibility between the fetus and its mother. Two main causes - Rh incompatibility (responsible for the most severe form) - ABO incompatibility Occur when an Rh- woman (a woman whose blood cells lack the Rh factor) conceives an Rh+ fetus. If a baby experiences erythroblastosis faetalis in the womb, They may be given intrauterine blood transfusions to reduce anemia. When the baby’s lungs and heart mature enough for delivery, a doctor may recommend delivering the baby early. After a baby is born, further blood transfusions may be necessary. Giving the baby fluids intravenously can improve low blood pressure. The baby may also need temporary breathing support from a ventilator or mechanical breathing machine.  Preventive treatment for HDN RhoGAM, or Rh immunoglobulin This is administered as a shot at around the 28th week of pregnancy. The shot is administered again at least 72 hours after birth if the baby is Rh+. Can reduce mother’s reaction to the baby’s Rh+ blood cells. This prevents adverse reactions for the mother if any of the baby’s placenta remains in the womb. Questions: 1. What is Haematopoiesis? 2. Illustrate the haematopoiesis with a diagram. 3. Describe the physiological basis of Haemolytic disease of the newborn. THANK YOU