0. Anatomy

• plasma: consist mostly of water, carries nutrients, wastes, ions, hormones, clotting factors, albumin, and antibodies

  • albumin: promotes the blood’s ability to hold water and maintain pressure inside the blood vessels

• erythrocytes (RBC)

  • 5 million/mm^3 in males, 4.5 in females
  • mature RBC have no nucleus, they do not grow to repair, lifespan 120d
  • old RBC are removed from the body by the liver and the spleen
  • produced in the red marrow, emerge as reticulocytes
  • production: begin with large nucleated stem cells, hemoglobin accumulates within the cytoplasm, regulated by erythropoeisis

• leukocytes (WBC)

  • include neutrophils, eosinophils, basophils, monocytes, and lymphocytes
  • produced in the bone marrow from their respect stem cells
  • f(x): to defend tissues against infections and foreign substances

• Platelets

  • produced in the bone marrow
  • essential for blood clotting
  • clotting factors are formed in the liver, enter the blood, and become active in response to injury
  • during clot formation, platelets become sticky and trigger the deposition of an insoluble clotting protein called fibrin
  • platelets and fibrin form a dense mesh at a wound, preventing blood loss
  • vitamin K is required for the synthesis of the prothrombin and thrombin clotting factors

• Diagnostic procedures

  • CBC, hemoglobin, hematocrit 红细胞压积, serum chemistry, and enzyme and hormone levels
    • size, shape, and ratio of one cell type to another
  • bone marrow spear: used for malignant blood disorders and increase or decrease in blood counts; obtained by needle aspiration

1. Anemia

• low number of RBC
• causes include hemorrhage, excessive destruction og RBCs, nutritional deficiency, and chronic diseases
• signs & symptoms: hypoxia, fatigue, palpitations, pallor, shock; for hemolysis: jaundice and enlargement of the spleen; tachycardia, heart murmurs
• diagnosis: microscopic examination and blood diagnosis

1.1 Iron-Deficiency Anemia

• prevalence: preschool children and adolescent and adult females
• risk factor: excessive blood loss, menstruation, pregnancy, rapid frowth during adolescence
• first stage: negative iron balance; second stage: iron stores in the body becomes depleted ( hemoglibin becomes impaired, RBC lose it’s shape and appear like a cigar or pencil);
• signs & symptoms: weakness, fatigue, cognitive performance & behavior & growth in preschool and school age children; iron deficiency during pregnancy increases overall infant mortality or death