Blood and Circulatory System Disorders PDF

Chapter 10 Blood and Circulatory System Disorders Review of the Circulatory System  The circulatory system consists of the cardiovascular system and lymphatic system  This chapter will cover the blood vessels, the blood, and associated disorders. Copyright © 2...

Chapter 10 Blood and Circulatory System Disorders Review of the Circulatory System  The circulatory system consists of the cardiovascular system and lymphatic system  This chapter will cover the blood vessels, the blood, and associated disorders. Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 2  Blood Vessels  Arteries—arterioles  Transport blood away from heart  Veins—venules  Return blood back to the heart  Capillaries  Microcirculation within tissues  Systemic circulation  Exchange of gases, nutrients, and wastes in tissues  Pulmonary circulation  Gas exchange in lungs Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 3 Blood Vessels (Cont.) Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 4  Histology of Arteries and Veins  Tunica intima—endothelium (simple squamous epithelium)  Tunica media—middle layer, mostly smooth muscle  Tunica adventitia (externa)—connective tissue with fibrocytes, collagen (type I), and elastic fibers Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 5  Blood Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 6  Composition of Blood  Plasma  Plasma proteins  Cellular component  Erythrocytes  Leukocytes  Thrombocytes (platelets) Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 7 Components of Blood and Their Functions Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 8  Hematopoiesis Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 9 Normal Red Blood Cells Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 10  Erythrocytes (Red Blood Cells)  Biconcave flexible discs  No nucleus in mature state  Contains hemoglobin  Globin portion  Heme group  Life span—120 days  Erythropoietin produced in the kidney stimulates erythrocyte production. Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 11 Normal Blood Cells Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 12 Breakdown of Hemoglobin Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 13  Blood Clotting—Hemostasis  Three steps:  Vasoconstriction or vascular spasm after injury  Platelet clot  Coagulation mechanism  Plasmin will eventually break down the blood clot. Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 14 Hemostasis and Anticoagulant Drugs Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 15  Blood Typing Blood typing is based on antigens in the plasma membrane of the erythrocytes.  ABO system  Based on the presence or absence of specific antigens  Antibodies in the blood plasma  Rh system  Antigen D in plasma membrane: Rh+  Absence of antigen D: Rh Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 16 ABO Blood Groups Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 17  Diagnostic Tests  Complete blood count (CBC)  Includes total red blood cells (RBCs), white blood cells (WBCs), and platelets  Leukocytosis (increased WBCs) Associated with inflammation or infection  Leukopenia (decreased WBCs) Associated with some viral infections, radiation, chemotherapy  Increased eosinophils Common in allergic responses  Differential count for WBCs Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 18  Diagnostic Tests (Cont.)  Morphology  Observed with blood smears  Shows size, shape, uniformity, maturity of cells Different types of anemia can be distinguished.  Hematocrit  Percent by volume of cellular elements in blood  Hemoglobin  Amount of hemoglobin per unit volume of blood  Mean corpuscular volume (MCV) Indicates the oxygen-carrying capacity of blood Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 19  Diagnostic Tests (Cont.)  Reticulocyte count  Assessment of bone marrow function  Chemical analysis  Determines serum levels of components, such as iron, vitamin B12, folic acid, cholesterol, urea, glucose  Bleeding time  Measures platelet function  Prothrombin time (PT) and partial thromboplastin time (PTT)  Measure function of various factors in coagulation process  International normalized ratio (INR) is a standardized version. Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 20  Blood Therapies  Whole blood, packed red blood cells, packed platelets  For severe anemia or thrombocytopenia  Plasma or colloid volume-expanding solutions  To maintain blood volume  Artificial blood products  Compatible with all blood types  None of them can perform all the complex functions of normal whole blood. Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 21  Blood Therapies (Cont.)  Epoetin alfa  Artificial form of erythropoietin Before certain surgical procedures Anemia related to cancer Chronic renal failure  Bone marrow or stem cell transplantation  Close tissue match necessary Treatment of some cancers Severe immunodeficiency Severe blood cell diseases  Drug treatment  Aids in the clotting process Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 22 Blood Dyscrasias Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 23  The Anemias  Anemia causes a reduction in oxygen transport.  Basic problem is hemoglobin deficit  Oxygen deficit leads to:  Less energy production in all cells Cell metabolism and reproduction diminished  Compensation mechanisms Tachycardia and peripheral vasoconstriction  General signs of anemia Fatigue, pallor (pale face), dyspnea, tachycardia Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 24  The Anemias (Cont.)  Oxygen deficit leads to:  Decreased regeneration of epithelial cells Digestive tract becomes inflamed and ulcerated, leading to stomatitis Inflamed and cracked lips Dysphagia Hair and skin may show degenerative changes.  Severe anemia may lead to angina or congestive heart failure (CHF). Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 25  Iron Deficiency Anemia  Insufficient iron impairs hemoglobin synthesis.  Microcytic, hypochromic RBCs Result of low hemoglobin concentration in cells  Very common  Ranges from mild to severe  Occurs in all age groups, but more common in women of childbearing age  Estimated that one in five women is affected Proportion increases for pregnant women  Frequently sign of an underlying problem Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 26 Iron Deficiency Anemia—Blood Smear Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 27 Iron Deficiency Anemia: Causes  Dietary intake of iron below minimum requirement  Chronic blood loss  As from bleeding, ulcer, hemorrhoids, cancer  Impaired duodenal absorption of iron  In many disorders, malabsorption syndromes  Severe liver disease  May affect iron absorption as well as storage Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 28  Iron Deficiency Anemia: Signs and Symptoms  Pallor of skin and mucous membranes  Fatigue, lethargy, cold intolerance  Irritability  Degenerative changes  Stomatitis and glossitis  Menstrual irregularities  Delayed healing  Tachycardia, heart palpitations, dyspnea, syncope Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 29  Pernicious Anemia: Vitamin B12 Deficiency  Basic problem is lack of absorption of vitamin B12 because of lack of intrinsic factor  Intrinsic factor secreted by gastric mucosa  Required for intestinal absorption of vitamin B12  Characterized by very large, immature, nucleated erythrocytes  Carry less hemoglobin  Shorter life span Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 30  Pernicious Anemia: Vitamin B12 Deficiency (Cont.)  Dietary insufficiency is very rarely a cause.  Genetic factors have been implicated.  More common in light-skinned women of northern European ancestry  Often accompanies chronic gastritis  May also be an outcome of gastric surgery Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 31 Development of Pernicious Anemia Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 32  Vitamin B12 and Nerve Cells  Vitamin B12 is needed for the function and maintenance of neurons.  Significant deficit of the vitamin will cause symptoms in the peripheral nerves.  These may be reversible. Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 33 Vitamin B12 Deficiency Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 34  Pernicious Anemia: Vitamin B12 Deficiency (Cont.)  Manifestations in addition to those typical for anemias  Tongue is typically enlarged, red, sore, and shiny.  Digestive discomfort, often with nausea and diarrhea  Feeling of pins and needles, tingling in limbs  Diagnostic tests  Microscopic examination (erythrocytes)  Bone marrow examination (hyperactive)  Vitamin B12 serum levels below normal  Presence of hypochlorhydria or achlorhydria Presence of gastric atrophy Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 35  Myelodysplastic Syndromes  Diseases that involve inadequate production of cells by the bone marrow  Signs and symptoms include anemia; dependent on type of deficiencies that occur  May be idiopathic or occur after chemotherapy or radiation treatment  Treatment measures depend on deficiency type.  Transfusion replacement  Chelation therapy to reduce iron overload  Bone marrow transplantation Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 36  Aplastic Anemia  Impairment or failure of bone marrow  May be temporary or permanent  Often idiopathic but possible causes include:  Myelotoxins Radiation, industrial chemicals, drugs  Viruses Particularly hepatitis C  Genetic abnormalities Fanconi’s anemia  Myelodysplastic syndrome Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 37  Aplastic Anemia (Cont.)  Blood counts indicate pancytopenia.  Anemia, leukopenia, thrombocytopenia  Bone marrow biopsy may be required.  Erythrocytes often appear normal.  Identification of cause and prompt treatment needed for bone marrow recovery  Removal of any bone marrow suppressants  Failure to identify cause and treat effectively is life-threatening! Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 38  Hemolytic Anemia  Results from excessive destruction of RBCs  Causes  Genetic defects  Immune reactions  Changes in blood chemistry  Infections such as malaria  Toxins in the blood  Antigen-antibody reactions Incompatible blood transfusion Erythroblastosis fetalis Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 39  Sickle Cell Anemia  Genetic condition  Autosomal  Incomplete dominance  Anemia occurs in homozygous recessive.  Diagnostic testing is available.  More common in individuals of African ancestry Heterozygous condition is somewhat protective against malaria. One in ten African Americans is heterozygous for the trait. Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 40 Sickle Cell Anemia (Cont.) Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 41  Sickle Cell Anemia (Cont.)  Abnormal hemoglobin (HbS)  Sickle cell crisis occurs whenever oxygen levels are lowered.  Altered hemoglobin is unstable and changes shape in hypoxemia.  Sickle-shaped cells are too large to pass through the microcirculation.  Obstruction leads to multiple infarctions and areas of necrosis. Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 42 Sickle Cell Anemia (Cont.) Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 43 Sickle Cell Anemia (Cont.) Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 44  Sickle Cell Anemia (Cont.)  Multiple infarctions affect brain, bones, organs  In addition to basic anemia:  Hyperbilirubinemia, jaundice, gallstones Caused by high rate of hemolysis  Clinical signs  Do not usually appear until the child is about 12 months old Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 45  Sickle Cell Anemia: Signs and Symptoms  Severe pain because of ischemia of tissues and infarction  Pallor, weakness, tachycardia, dyspnea  Hyperbilirubinemia—jaundice  Splenomegaly  Vascular occlusions and infarctions  In lungs Acute chest syndrome  Smaller blood vessels Hand-foot syndrome  Delay of growth and development  Congestive heart failure Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 46  Sickle Cell Anemia (Cont.)  Diagnostic tests  Blood test Hemoglobin electrophoresis  Prenatal DNA analysis  Treatment  Hydroxyurea has reduced the frequency of this crisis.  Dietary supplementation with folic acid  Bone marrow transplantation  Immunization in children Against pneumonia, influenza, meningitis Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 47 Comparison of Selected Anemias Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 48  Polycythemia  Primary polycythemia—polycythemia vera  Increased production of erythrocytes and other cells in the bone marrow  Neoplastic disorder  Serum erythropoietin levels are low.  Secondary polycythemia—erythrocytosis  Increase in RBCs in response to prolonged hypoxia  Increased erythropoietin secretion  Compensation mechanism to provide increased oxygen transport Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 49  Polycythemia: Signs and Symptoms  Distended blood vessels, sluggish blood flow  Increased blood pressure  Hypertrophied heart  Hepatomegaly  Splenomegaly  Dyspnea  Headaches  Visual disturbances  Thromboses and infarctions Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 50  Polycythemia (Cont.)  Diagnostic tests  Increased cell counts  Increased hemoglobin and hematocrit values  Hypercellular bone marrow  Hyperuricemia  Treatment  Identify cause  Drugs or radiation Suppression of bone marrow activity  Periodic phlebotomy Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 51  Indications of Blood-Clotting Disorders  Persistent bleeding from gums  Repeated epistaxis  Petechiae  Pinpoint, flat, red spots on skin and mucous membrane  Frequent purpura and ecchymosis  More than normal bleeding in trauma  Bleeding into joint—hemarthroses  Swollen, red, painful  Hemoptysis Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 52  Blood-Clotting Disorders  Hematemesis  Coarse brown particles (coffee ground emesis)  Blood in feces  Black or occult  Anemia  Feeling faint and anxious  Low blood pressure  Rapid pulse Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 53  Petechiae Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 54  Hemophilia A  Classic hemophilia  Deficit or abnormality of factor VIII  Most common inherited clotting disorder  X-linked recessive trait  Manifested in men, carried by women  Varying degrees of severity  Prolonged bleeding after minor tissue trauma  Spontaneous bleeding into joints  Possible hematuria or blood in feces Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 55  Hemophilia A (Cont.)  Diagnostic tests  Bleeding time and PT normal  PTT, activated PTT (aPTT), coagulation time prolonged  Serum levels of factor VIII are low.  Treatment  Desmopressin (DDAVP)  Replacement therapy for factor VIII Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 56  Von Willebrand’s Disease  Most common hereditary clotting disorder  Three major types  Signs and symptoms include:  Skin rashes  Frequent nosebleeds  Easy bruising  Bleeding of gums  Abnormal menstrual bleeding  Treatment based on type and severity Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 57  Disseminated Intravascular Coagulation  Involves both excessive bleeding and clotting  Excessive clotting in circulation  Thrombi and infarcts occur.  Clotting factors are reduced to a dangerous level.  Widespread, uncontrollable hemorrhage results.  Very poor prognosis, with high fatality rate  Complication of many primary problems  Obstetrical complications, such as abruptio placentae  Infections  Carcinomas  Major trauma Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 58 Disseminated Intravascular Coagulation (Cont.) Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 59  Thrombophilia  Group of inherited or acquired disorders  Risk of abnormal clots in veins or arteries  Blood testing for clotting factor levels and abnormal antibody levels  Causative condition should be treated. Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 60  The Leukemias  Group of neoplastic disorders involving white blood cells  Uncontrolled WBC production in bone or lymph nodes  Other hemopoietic tissues are reduced.  One or more types of leukocytes are undifferentiated, immature, and nonfunctional.  Large numbers released into general circulation  Infiltrate lymph nodes, spleen, liver, brain, other organs Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 61  Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 62  The Leukemias (Cont.)  Acute leukemias (ALL and AML)  High proportion of immature nonfunctional cells in bone marrow and peripheral circulation  Onset usually abrupt , marked signs of complications Occurs primarily in children and younger adults  Chronic leukemias (CLL and CML)  Higher proportion of mature cells  Insidious onset  Mild signs and better prognosis Common in older adults Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 63 Acute Lymphocytic Leukemia Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 64  Signs and Symptoms of Acute Leukemia  Usual signs at onset  Frequent or uncontrolled infections  Petechiae and purpura  Signs of anemia  Severe and steady bone pain  Weight loss, fatigue, possible fever  Enlarged lymph nodes, spleen, liver  Headache, visual disturbances, drowsiness, vomiting Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 65  The Leukemias (Cont.)  Diagnostic tests  Peripheral blood smears Immature leukocytes and altered numbers of WBCs Numbers of RBCs and platelets decreased Bone marrow biopsy for confirmation  Treatment  Chemotherapy  ALL in young children responds well to drugs  Biological therapy (interferon) May be used to stimulate the immune system Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 66  Complications of Leukemia  Opportunistic infections, including pneumonia  Sepsis  Congestive heart failure  Hemorrhage  Liver failure  Renal failure  CNS depression and coma Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 67  Multiple Myeloma  Neoplastic disease that involves increased production of plasma cells in bone marrow  Unknown cause  Occurs in older adults  Production of other blood cells is impaired  Multiple tumors in bone  Loss of bone  Severe bone pain  Prognosis poor, with short life expectancy Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 68 Multiple Myeloma of the Skull Copyright © 2014, 2011, 2006 by Saunders, an imprint of Elsevier, Inc. 69