Hema

• Athanasius Kircher described "worms" in the blood


  1657
• Anton van Leeuwenhoek gave an account of RBCs


  1674
• Giulio Bizzozero described platelets as "petites plaques"


  1800s
• James Homer Wright development of Wright stain


  1902
• Joseph and Wallace Coulter developed the first electronic counter


  1953
• Hematology


  The study of the formed (cellular) elements of the blood

  
• Hematology


  • Deals with the physiology, pathology, etiology, diagnosis, treatment, prognosis and prevention of blood-related disorders

  
• Blood


  • Transports oxygen from lungs to tissues
  • Clears tissues of carbon dioxide
  • Transports glucose, proteins and fats
  • Moves wastes to the liver and kidneys
• Formed Elements of the Blood

  • Erythrocytes
  • Immature Erythrocytes (Reticulocyte)
  • Mature Erythrocytes (Discocyte)
  • Leukocytes
  • Granulocytes
  • Neutrophils
  • Eosinophils
  • Basophils
  • Agranulocytes
  • Lymphocytes
  • Monocytes
  • Plasma Cells
  • Thrombocytes

  
• Erythrocytes


  • More commonly known as Red Blood Cells
  • Anucleate, biconcave discoid cell that contain reddish protein that transports gases to and from different parts of the body
  • RBCs appear pink to red
  • Measure 6 to 8 mm in diameter
  • With a zone of pallor that occupies one third of their center

  
• Erythrocytes


  • Lifespan: 120 days
  • RBC membrane: 50% Proteins, 40% Lipids, 10% Carbohydrates
• Leukocytes


  • Granulocytes
  • Neutrophils (50-70%)
  • Eosinophils (1-3%)
  • Basophils (0-2%)
  • Agranulocytes
  • Lymphocytes (18-42%)
  • Monocytes (2-11%)
• Leukocytes: NEUTROPHIL


  • Has pink to rose-violet specific granules
  • Multilobed (2-5 lobes) nuclei
  • Phagocytic cells
  • Engulfs and destroys microorganisms and foreign material
• Leukocytes: EOSINOPHIL


  • Has reddish-orange granules
  • Usually has 2 lobes
  • Release enzymes that disable parasites
• Leukocytes: BASOPHIL


  • Has dark-purple to blue-black irregular granules
  • Unsegmented or bilobed
  • Release mediators of inflammation
• Leukocytes: LYMPHOCYTE


  • Pale to moderate blue cytoplasm
  • Round or oval-shaped nucleus and may be slightly indented
  • Slightly larger than RBCs
  • Function in destroying cancer cells, cells infected by viruses, and foreign invading cells
• Leukocytes: MONOCYTE


  • Blue-gray cytoplasm
  • Contains fine azure granules
  • Round, kidney shaped nucleus and may show brainlike convolutions
  • Phagocytic cells in many places of body
• Thrombocytes


  • More commonly known as platelets
  • Measure 2-4um in diameter
  • Light blue to purple, very granular
  • Responsible for blood clotting

  
• Whole blood


  • The most common body fluid analyzed in the hematology section
  • Obtained by using a collection tube with an anticoagulant
  • Most tests performed in the hematology section require blood that has been collected in tubes with a lavender stopper that contain the anticoagulant EDTA

  
• Tests Performed in the Hematology Section

  • Cell Counting
  • Manual Cell Count
  • Improved Neubauer Counting Chamber (Hemocytometer)
  • Automated Cell Count

  
• Neubauer Counting Chamber


  • Used for manual cell counting
• Peripheral Blood Smear


  • Thick Blood smear: Used to screen for blood parasitic organisms
  • Thin Blood Smear: Used to identify blood parasites, Used in visualizing and identifying blood cells (manual differential counting)

  
• Thin Blood Film Preparation: Wedge Type Method

  1. Transfer a drop of blood to the stationary slide about .25 inch from the frosted end

  2. Position the spreader slide at a 25<, allow the blood to spread to the back edge of the spreader slide

  3. Immediately push the spreader slide forward with a smooth and rapid stroke maintaining the angle

  4. Air dry rapidly but thoroughly before staining
• Qualities of a Good Thin Blood Film

  • Cover at least half the length of the slide
  • Smear should be narrower than the slide
  • Smooth spread should display a gradual transition from thick to thin - No waves, No streaks, No troughs, No holes or bubbles
  • Straight feathered edge
  • Contain at least 10 LPF in which 50% of the RBCs do not overlap

  
• Factors Affecting a Good Thin Blood Film

  Thick smear: Light Pressure, High angle of the spreader slide, Large drop of blood, Fast spreading

  Thin smear: Increased pressure, Low angle of the spreader slide, Small drop of blood, Slow spreading