HEMATOLOGY

• logos- study
• hematology

  • study of blood
  • includes the morphologic appearance, function, and disease of blood
  • study of formed elements in blood
• The total blood volume in adults is 5-6 liters or 7-8% of body weight
• plasma - liquid portion of anticoagulated blood
• serum - liquid portion of clotted blood, clear and straw colored
• WHOLE BLOOD INCLUDES

  • Erythrocytes
  • Leukocytes
  • Plasma
  • Platelets
• leukocytes and platelets - make up the buffy coat when specimen is centrifuged
• plasma

  • composed of 90% water and contains enzymes, proteins, hormones, lipids, and salts
  • appears hazy and pale yellow
• 45% of blood are composed by formed elements; RBC,WBC,Platelets
• The remaining 55% of blood is composed of 90% water and 10% proteins, CHO, vitamins, hormones, enzymes, lipids, and salts
• arterial blood - bright scarlet red
• venous blood - dark red
• heme- blood
• Viscosity - resistance to flow / thick and sticky fluid that normally flows with difficulty
• specific gravity - 1.055-1.065
• pH- 7.35 to 7.45
• MOST COMMON HEMATOLOGIC PROCEDURE

  • COMPLETE BLOOD COUNT
  • ERYTHROCYTE SEDIMENTATION RATE (ESR)
  • BLOOD INDICES
  • RETICULOCYTE COUNT (RETICS)
• SAMPLE COLLECTION AND HANDLING

  • Venipuncture procedure
  • Using syringe method
  • using evacuated tube system (ETS)
  • Butterfly collection
• WHOLE BLOOD - most commonly analyzed bodily fluid in the hematology and is composed of plasma and cells
• TESTS PERFORMED IN THE HEMATOLOGY SECTION

  • Complete blood count
  • Differential (Diff)
  • Hematocrit (Hct)
  • Hemoglobin (Hgb)
  • Indices
  • Mean corpuscular hemoglobin (MCH)
  • Mean corpuscular hemoglobin concentration (MCHC)
  • Mean corpuscular volume (MCV)
  • Platelet count
  • Red blood cell (RBC) count
  • Red Cell distribution width (RDW)
  • White blood cell (WBC) count
  • Body fluid analysis
  • Bone marrow
  • Erythrocyte sedimentation rate
  • Reticulocyte count
  • Sickle cell
  • Special stains
• differential (diff) - determines the different types of wbc and evaluates red blood cell and platelet morphology (may be examined microscopically through peripheral blood smear using wright's stain)
• Hematocrit (hct) - determines the volume of RBC packed by centrifugation
• Hemoglobin - Determines oxygen carrying capacity of rbc and amount of hemoglobin
• Indices- Calculations to determine the size of red blood cells and amount of hemoglobin
• Mean corpuscular hemoglobin - determines the amount of hgb in rbc
• mean corpuscular hemoglobin concentration - determines the size of hgb in rbc and compares it to the size of the cell
• Mean corpuscular volume - determines the size of rbc
• Platelet count - determines the number of platelet in circulating blood
• Red blood cell count - determines the number of red blood cell in circulating blood
• Red Cell distribution width - determine the differences in sizes of RBC
• White blood cell count - determines the number of white blood cells in circulating blood
• Body fluid analysis - determines the number and type of cells in various body fluid
• bone marrow - determines the number and types of cell in the bone marrow
• Erythrocyte sedimentation rate - determines the rate of rbc sedimentation (nonspecific test for inflammatory disorder)
• Reticulocyte count - evaluates bone marrow production of rbc
• sickle cell - screening test for hgb s (SICKLE CELL ANEMIA)
• special stains - determine the type of leukemia or other cellular disorders
• Reasons for specimen rejection

  • Test order requisition does not match with the identification of the patient
  • Unlabeled specimen
  • Hemolyzed sample
  • Wrong specimen collection
  • Wrong tube
  • Clotted specimen for cbc
  • Contaminated specimen
  • Lipemic specimen
• COMPLETE BLOOD COUNT

  • Most frequent blood test
  • Provides detailed information about the cells in the blood
  • Screening test for most diseases
• CBC other names

  • Full blood count
  • Full blood exam