Blood Components and Blood Types

Blood Components

• Whole blood: composed of RBCs, WBCs, and platelets suspended in plasma
• Packed red blood cells (RBCs): concentrated RBCs with minimal plasma and WBCs
• Fresh frozen plasma (FFP): frozen plasma containing coagulation factors
• Platelets: concentrated platelets with minimal plasma and RBCs
• Cryoprecipitate: frozen precipitate of FFP containing fibrinogen, factor VIII, and XIII

Blood Types

• ABO blood group system:
  • A and B antigens on RBCs
  • A and B antibodies in plasma
  • Four main blood types: A, B, AB, and O
• Rh blood group system:
  • RhD antigen on RBCs
  • Rh positive (RhD antigen present) or Rh negative (RhD antigen absent)
• Other blood group systems: Kell, Duffy, Kidd, MNS, and P

Blood Transfusion

• Indications:
  • Anemia
  • Bleeding or hemorrhage
  • Surgical procedures
  • Trauma
• Contraindications:
  • Hemolytic disease of the newborn
  • Autoimmune hemolytic anemia
• Blood transfusion reactions:
  • Acute hemolytic reaction
  • Febrile non-hemolytic reaction
  • Allergic reaction
  • Transfusion-related acute lung injury (TRALI)

Hemostasis

• Primary hemostasis: platelet plug formation
• Secondary hemostasis: coagulation cascade
• Coagulation factors:
  • Intrinsic pathway: XII, XI, IX, VIII
  • Extrinsic pathway: VII, tissue factor
  • Common pathway: X, V, II, I
• Fibrinolysis: breakdown of fibrin clots by plasmin

Anemia

• Definition: decreased RBC mass or hemoglobin concentration
• Classification:
  • Microcytic (small RBCs): iron deficiency, thalassemia
  • Macrocytic (large RBCs): vitamin B12 or folate deficiency
  • Normocytic (normal RBC size): chronic disease, bone marrow failure
• Symptoms:
  • Fatigue
  • Weakness
  • Shortness of breath
  • Pallor

Bleeding Disorders

• Platelet disorders:
  • Thrombocytopenia (low platelet count)
  • Thrombasthenia (platelet dysfunction)
• Coagulation disorders:
  • Hemophilia A (factor VIII deficiency)
  • Hemophilia B (factor IX deficiency)
  • Von Willebrand disease (VWF deficiency)
• Symptoms:
  • Easy bruising
  • Petechiae
  • Prolonged bleeding
  • Hematomas

Blood Components

• Whole blood consists of RBCs, WBCs, and platelets suspended in plasma
• Packed red blood cells (RBCs) are concentrated RBCs with minimal plasma and WBCs
• Fresh frozen plasma (FFP) is frozen plasma containing coagulation factors
• Platelets are concentrated platelets with minimal plasma and RBCs
• Cryoprecipitate is a frozen precipitate of FFP containing fibrinogen, factor VIII, and XIII

Blood Types

• ABO blood group system: A and B antigens on RBCs, A and B antibodies in plasma
• Four main blood types: A, B, AB, and O
• Rh blood group system: RhD antigen on RBCs, Rh positive (RhD antigen present) or Rh negative (RhD antigen absent)
• Other blood group systems: Kell, Duffy, Kidd, MNS, and P

Blood Transfusion

• Indications: anemia, bleeding or hemorrhage, surgical procedures, and trauma
• Contraindications: hemolytic disease of the newborn, autoimmune hemolytic anemia
• Blood transfusion reactions: acute hemolytic reaction, febrile non-hemolytic reaction, allergic reaction, and transfusion-related acute lung injury (TRALI)

Hemostasis

• Primary hemostasis: platelet plug formation
• Secondary hemostasis: coagulation cascade
• Coagulation factors: intrinsic pathway (XII, XI, IX, VIII), extrinsic pathway (VII, tissue factor), common pathway (X, V, II, I)
• Fibrinolysis: breakdown of fibrin clots by plasmin

Anemia

• Definition: decreased RBC mass or hemoglobin concentration
• Classification: microcytic (small RBCs), macrocytic (large RBCs), normocytic (normal RBC size)
• Microcytic anemia: iron deficiency, thalassemia
• Macrocytic anemia: vitamin B12 or folate deficiency
• Normocytic anemia: chronic disease, bone marrow failure
• Symptoms: fatigue, weakness, shortness of breath, pallor

Bleeding Disorders

• Platelet disorders: thrombocytopenia (low platelet count), thrombasthenia (platelet dysfunction)
• Coagulation disorders: hemophilia A (factor VIII deficiency), hemophilia B (factor IX deficiency), von Willebrand disease (VWF deficiency)
• Symptoms: easy bruising, petechiae, prolonged bleeding, hematomas