Hematology: Blood Physiology

Components of Blood

• Red Blood Cells (RBC/Erythrocytes) – Transports Oxygen & Carbon Dioxide
• White Blood Cells (WBC/Leukocytes) – Part of the Immune System
• Platelets (Thrombocytes) – Assist Clotting
• Plasma – Liquid Component of Blood
  • Contains Proteins, Nutrients & Hormones

Half-Life

• RBC: 120 Days
• Platelets: 7 Days
• WBC: 1-2 Days

Erythropoietin (EPO)

• Function: Stimulates Erythropoiesis (RBC Production in Bone Marrow)
• Primary Stimulus: Hypoxia
• Primary Source:
  • Adults: Renal Cortex
  • Fetus: Liver
• Hematopoiesis Site: Bone Marrow
  • In Myelofibrosis: Spleen
• Exogenous Administration:
  • Used in Anemia from Chronic Kidney Disease
  • Has Been Used as a Performance-Enhancing Drug in Sports
  • Has Not Been Useful in Treatment of Acute Hemorrhage

Blood Typing

• Blood Type: Refers to Antigens Present on RBC
  • Type A – Has Type A Ag
  • Type B – Has Type B Ag
  • Type AB – Has Both Type A & B Ag
  • Type O – Has No Ag
• Blood Donation:
  • RBC Donation:
    • Universal Recipient: Type AB
    • Universal Donor: Type O Mn
  • Plasma Donation:
    • Universal Plasma Recipient: Type O
    • Universal Plasma Donor: Type AB (No Antibodies)