Introduction to Blood

• Blood is an essential fluid for sustaining life

Introduction to Blood

• Blood makes up approximately 7-8% of body weight.
• Blood is composed of plasma and cellular components

Blood Plasma: The Liquid Component

• Blood plasma makes up 55% of total blood volume
• Plasma is composed of 90% water and 10% dissolved substances
• Plasma contains proteins, nutrients, hormones, and clotting factors

Red Blood Cells (Erythrocytes)

• Red blood cells are biconcave discs in shape
• Red blood cells function in oxygen transport via hemoglobin
• Red blood cells have a lifespan of 120 days
• Normal red blood cell levels are 4.5-5.5 × 10^12 cells/L

White Blood Cells (Leukocytes)

• White blood cells consist of neutrophils, lymphocytes, monocytes, eosinophils, and basophils
• White blood cells function in immune defense
• Normal white blood cell levels are 4.5-11 × 10^9 cells/L

Platelets (Thrombocytes)

• Platelets are cell fragments from megakaryocytes
• Platelets function in blood clotting
• Platelets lifespan is 8-10 days
• Normal platelet levels are 150-450 × 10^9 cells/L

Hematopoiesis

• Hematopoiesis is blood cell production in red bone marrow
• Hematopoiesis is a stem cell differentiation process
• Hematopoiesis is regulated by hormones like erythropoietin

Blood Type Basics

• Blood type is determined by the presence or absence of antigens
• The two classification systems for blood type are ABO and Rh
• Blood type is inherited from parents

The ABO System

• The four blood types in the ABO system are A, B, AB, and O
• ABO blood types are based on the presence of A and/or B antigens
• There are natural antibodies against absent antigens
• Type O blood has anti-A and anti-B antibodies

The Rh System

• Blood can be positive or negative based on D antigen presence
• Rh negative individuals lack the D antigen
• The Rh system is important in pregnancy and transfusions

Blood Type Distribution

• Type O is 44% of the population
• Type A is 42% of the population
• Type B is 10% of the population
• Type AB is 4% of the population

Blood Typing Procedure

• Blood typing uses anti-A and anti-B sera
• Agglutination reactions are observed
• Rh status is determined

Cross-Matching

• Cross-matching tests donor and recipient compatibility
• There are major and minor cross-matches
• Cross-matching is essential before transfusions

Transfusion Reactions

• Transfusion reactions are caused by incompatible blood types
• Symptoms of transfusion reactions include fever, chills, and shock
• Transfusion reactions can be life-threatening
• Prevention of transfusion reactions occurs through proper testing

Clinical Applications

• Emergency transfusions are a clinical application
• Surgical procedures are a clinical application
• Treatment of blood disorders is a clinical application
• Blood donation is important