Patho Ch. 10 Blood and Circulatory System Disorders Overview E2

RBC

erythrocyte

Hemoglobin (Hgb)

Contains iron, which carries oxygen.

Polycythemia

Over proliferation of all blood cells in bone marrow.

Anemia

Major pathophysiologic condition of RBC's that reduces oxygen transport in blood because of decrease in hemoglobin content.

Blood

Major transport system of the body.

Composition of Blood

Body contains approximately 5 liters of blood.

Hematocrit

Viscosity of blood (Solids).

Plasma

Yellow, clear fluid remaining after cells have been removed.

Serum

Fluid and solutes remaining after cells and fibrinogen have been removed from plasma.

Dyscrasia

Pathologic condition of blood that refers to disorders involving cell components of blood.

Erythrocytes (RBCs)

Biconcave, flexible, nonnucleated when mature, contain hemoglobin.

Life span of RBCs

120 days.

Thrombocytes

Aka platelets, essential part of the clotting process.

Hemostasis

Process of stopping bleeding.

Leukocytes

Large, nucleated cells responsible for immunity and protection.

Leukocytosis

Increase in WBCs, associated with inflammation or infection, WBC above 11,000 cells/microliter.

Leukemoid reaction

WBC above 50,000 cells/microliter due to cause other than leukemia.

Leukopenia

Decrease in leukocytes, WBC less than 4,000/microliter.

Iron Deficiency Anemia

Insufficient iron slows or stops hemoglobin synthesis, which reduces amount of oxygen transported in blood.

Clotting factors

Activated in circulating blood and begin a sequence of reactions.

Fibrinogen (Factor I)

Converted to fibrin threads.

Prothrombin (Factor II)

Formed and converted to thrombin.

Compensatory mechanisms

Increased due to decreased oxygen transport.

Iron Deficiency Anemia

A condition characterized by low levels of iron, often due to low dietary intake, chronic blood loss, or impaired absorption.

Etiology of Iron Deficiency Anemia

Causes include low dietary intake of iron, chronic blood loss from sources such as bleeding ulcers, hemorrhoids, cancer, excessive menstrual flow, and impaired absorption due to digestive disorders.

Signs and Symptoms of Iron Deficiency Anemia

Symptoms may include pale skin, fatigue, cold intolerance, irritability, brittle hair, ridged nails, spoon-shaped nails, stomatitis, glossitis, menstrual irregularities, delayed healing, tachycardia, palpitations, dyspnea, and syncope.

Vitamin B12 Deficiency / Pernicious Anemia

A type of megaloblastic anemia characterized by very large, immature, nucleated erythrocytes due to a deficit of Vitamin B12.

Etiology of Vitamin B12 Deficiency

Caused by malabsorption of vitamin B12, often due to lack of intrinsic factor, autoimmune reactions, dietary deficiency, gastrectomy, or resection of the ileum.

Signs and Symptoms of Vitamin B12 Deficiency

Symptoms may include fatigue, dyspnea, tachycardia, ulcers in oral mucosa, hair and skin changes, enlarged red sore shiny tongue, nausea, diarrhea, tingling or burning sensations, and loss of muscle control/coordination.

Aplastic Anemia

A condition resulting from impairment or failure of bone marrow leading to decreased numbers of erythrocytes, leukocytes, and platelets.

Etiology of Aplastic Anemia

Causes include myelotoxins, radiation, industrial chemicals, certain medications, viruses, autoimmune diseases, and genetic disorders.

Signs and Symptoms of Aplastic Anemia

Symptoms may include general anemia symptoms, leukopenia leading to recurrent infections, and thrombocytopenia resulting in petechiae.

Thrombocytopenia

A condition characterized by a reduction in platelet counts, which can lead to excessive bleeding.

Thrombocytopenia petechiae

Flat, red, pinpoint hemorrhages on the skin indicating low platelet counts and a tendency to bleed excessively.

Hemolytic Anemias

A group of anemias where erythrocyte destruction (hemolysis) outpaces replacement, which can be acute or chronic.

Sickle Cell Anemia (SCA)

An autosomal hemoglobinopathy characterized by abnormal hemoglobin (HbS) that distorts and crystallizes red blood cells into a crescent shape.

Pathophysiology of Sickle Cell Anemia

Abnormal RBCs have a lifespan of 10-20 days, leading to hemolysis and obstruction of small vessels, resulting in thrombus formation and tissue necrosis.

Vasco-occlusive crises in Sickle Cell Anemia

Painful episodes occurring in individuals with infections or dehydration, involving large blood vessels and multiple organ infarctions.

Signs and Symptoms of Sickle Cell Anemia

Symptoms may include pallor, weakness, hyperbilirubinemia (jaundice), splenomegaly, vascular occlusions, chest pain, pain and swelling in hands, and frequent infections.