CARDIOVASCULAR SYSTEM BLOOD HEART BLOOD VESSELS BLOOD Chapter 17 Hematology=the study of blood Click Here For a Blood Tutorial CHARACTERISTICS OF BLOOD Liquid connective tissue 4-5 times more viscous than water Slightly alkaline Warmer than body temperature Volume is 4-6 liters • Men=5-6 L • Women=4-5 L Salt concentration of .85-.90% CHARACTERISTICS OF BLOOD • Heterogeneous mixture Non-living matrix called PLASMA (55%) Formed elements (45%) PLASMA FORMED ELEMENTS • Erythrocytes= red blood cells (RBC) • Leukocytes= white blood cells (WBC) • Thrombocytes= platelets FUNCTIONS OF BLOOD • Distribution Oxygen and carbon dioxide Hormones Wastes • Protection Clotting mechanisms Phagocytosis and antibody production • Regulation pH Body temperature Fluid and electrolyte balance ERYTHROCYTE • CHARACTERISTICS Most numerous formed element with (4.8 to 5.4 million per mm3) Very flexible No nucleus Biconcave disk Life span about 120 days Contains hemoglobin HEMOGLOBIN=Transport Pigment • Oxyhemoglobin • Deoxyhemoglobin • Carbaminohemoglobin Hemoglobin values: • Measured in grams per milliliter • 14 – 20 g/100 ml in infants • 13 – 18 g/100 ml in adult males • 12 – 16 g/100 ml in adult females ERYTHROPOIESIS =PRODUCTION OF RBC OCCURS IN THE RED BONE MARROW OF FLAT BONES AND IN SOME LONG BONES Regulation of Erythropoiesis • Hormonal Controls – Erythropoietin – RBC and Hemoglobin amounts – Availability of oxygen • Dietary Controls – Adequate amino acids, lipids, and carbs – Iron – Vitamin B12 and folic acid Regulation of Erythropoiesis Life Cycle of Erythrocytes ERYTHROCYTE DISORDERS • ANEMIA • POLYCYTHEMIA Insufficient #of RBCs Primary polycythemia Hemorrhagic anemia Secondary Hemolytic anemia polycythemia Aplastic anemia Low hemoglobin Pernicious anemia - macrocytes Iron deficiency - microcytes Abnormal hemoglobin Thalassemia Sickle cell Anemia Erythrocyte Disorder HEMATOCRIT • 47% +/- 5% in males • 45% +/- 5% in females LEUKOCYTES • CHARACTERISTICS Less numerous than RBC (less than 1% of blood with normal range of 4800 – 10,800 WBC/ml) Critical defense cells of the body Distinct nuclei present Capable of diapedesis Demonstrate positive chemotaxis Lack hemoglobin TYPES OF LEUKOCYTES • GRANULOCYTES Neutrophils (PMNs) Eosinophils Basophils • Agranulocytes Lymphocytes Monocytes TYPES OF LEUKOCYTES Mnemonic Devices: • Granulated versus agranulated – “Every Boy Needs Mommies Love!” • Relative Quantitates – “Never Let Monkeys Eat Bananas!” LEUKOPOIESIS LEUKOCYTE IMBALANCES • Leukocytosis (amounts greater than 11,000 WBC/ml) • Leukopenia (amounts less than 4,000 WBC/ml) • Leukemia Acute leukemia Chronic leukemia • Infectious Mononucleosis = kissing disease THROMBOCYTES • CHARACTERISTICS Involved in hemostasis Less than half the size of RBC Numerous (250,000400,000 per ml3) Actually cell fragments rather than true cells Life span is about 5-9 days FORMATION OF PLATELETS Regulated by thrombopoietin STAGES OF BLOOD CLOTTING • Step 1: Vascular spasms Endothelin Serotonin • Step 2: Formation of a platelet plug ADP Serotonin Thromboxane A2 von Willebrand factor STEP 3: COAGULATION • Phase 1: Formation of prothrombinase (also known as prothrombin activator) • Phase 2: Conversion of prothrombin to thrombin • Phase 3: Conversion of soluble fibrinogen into insoluble fibrin Phase 1: Intrinsic versus Extrinsic Pathways Phase 2 and 3: CLOTTING FACTORS Hemostasis Continued • Clot Retraction – Also known as Syneresis – Serum (plasma minus clotting factors) • Repair: PDGF – Stimulates smooth muscle and fibroblast cells to divide and rebuild the wall • Fibrinolysis – Plasmin = “clot buster” Factors Effecting Clot Formation • Normal coagulation: Normal platelet #s ALL clotting factors Vitamin K Calcium ions TF and PF3 Preventing Undesirable Clotting • • • • • Nitric oxide Prostacyclin (a prostoglandin) Vitamin E quinone Heparin Anti-prothrombin III and Protein C PLATELET DISORDERS • Thrombus • Embolus • Hemophilia • Thrombocytopenia • Impaired liver function • Disseminated Intravascular Coagulation (DIC) Effects of Drugs on Clotting • Aspirin = antiprostaglandin that inhibits thromboxane A2 • Heparin = natural anticoagulant produced by basophils and mast cells that inhibits thrombin by enhancing the activity of antithrombin III • Warfarin = (a.k.a. Coumadin) interfers with the action of vitamin K Summary of Formed Elements Summary of Formed Elements BLOOD TYPING • Blood types are base on the presence of agglutinogens (antigens) present on the red blood cell surface. • Also, based on presence of agglutinins (antibodies) in the plasma. • The ABO and Rh systems are based on antigenantibody type interactions. ABO BLOOD GROUPS BLOOD TYPES Blood Type A Type of Antigen? A antigen Type of Antibody? Anti-B Receive? B B antigen Anti-A B, O AB Both A and B antigens None None A, B, AB, O Both Anti-A and Anti-B O only O A, O Rhesus Factor Blood Type Presence of Type of Receive? D Antigen? Antibody? Rh Positive Yes None + and - No Anti-D - only Rh Negative BLOOD GROUPS Type O Type B 45% 10% Type A Type AB 42% 3% ABO BLOOD TYPING BLOOD TYPE TUTORIAL TEST YOUR KNOWLEDGE BLOOD GROUPING DISORDERS • Transfusion Reaction BLOOD GROUPING DISORDERS • Erythroblastosis fetalis