Blood Component Therapy

Blood Basics & Typing - Tiny Titans' Type

• ABO/Rh System:
  • Neonates: May lack isohemagglutinins (develop by 3-6 months). Maternal IgG anti-A/B can cross placenta.
  • Rh(D) typing critical: Prevents Hemolytic Disease of Newborn (HDN).
• Cross-matching:
  • Major: Donor RBCs vs Recipient Serum (Primary).
  • Minor: Donor Serum vs Recipient RBCs.
• Indications: Symptomatic anemia, active bleeding, coagulopathy.

  ⭐ Universal donor (RBCs): O Rh-negative. Universal donor (Plasma): AB. 📌 O-Negative: Oh! No antigens!

Red Cell Rhapsody - Ruby Rescuers

• Packed Red Blood Cells (PRBCs)
  • Indications: Symptomatic anemia, acute blood loss (Hb <7 g/dL in stable patients; higher thresholds for cyanotic heart disease, severe hypoxemia).
  • Dose: 10-15 mL/kg over 2-4 hours.
  • Expected rise: Hb by 2-3 g/dL.
  • Special Preparations:
    • Leukoreduced: Prevents CMV transmission, reduces Febrile Non-Hemolytic Transfusion Reactions (FNHTR).
    • Irradiated: Prevents Transfusion-Associated Graft-versus-Host Disease (TA-GVHD) in immunocompromised patients.
    • Washed: For IgA deficiency, history of recurrent severe allergic reactions.

⭐ One unit of PRBCs (or 10-15 mL/kg) is expected to raise hemoglobin by approximately 2-3 g/dL or hematocrit by 6-9%.

Platelet Power-Up - Clotting Crusaders

• Indications:
  • Prophylactic: Count <10,000-20,000/µL (stable aplastic anemia/chemo).
  • Therapeutic: Active bleeding + low platelets; Pre-procedure if count <50,000/µL.
  • Neonatal thresholds differ.
• Dose: 1 RDP unit/10 kg or 1 SDP unit (apheresis).
• Expected Increment: ↑30,000-50,000/µL per SDP (or 4-6 RDPs); adjust for peds.
• Platelet Refractoriness: Poor increment.
  • Causes: Immune (HLA/HPA alloimmunization); Non-immune (sepsis, splenomegaly, DIC, drugs).

⭐ For HLA alloimmunization-induced refractoriness, use HLA-matched or crossmatch-compatible platelets.

Plasma & Cryo Crew - Coagulation Champions

• Fresh Frozen Plasma (FFP)
  • Contents: All coagulation factors, plasma proteins (albumin, globulins).
  • Indications: Active bleeding with multiple coagulation factor deficiencies (e.g., liver disease, DIC), urgent warfarin reversal.
  • Dose: 10-20 mL/kg.
• Cryoprecipitate
  • Contents: Fibrinogen, Factor VIII (FVIII), Factor XIII (FXIII), von Willebrand Factor (vWF), fibronectin. 📌 Cryo is RICH in Fibrinogen, Factor 8, Factor 13, vWF.
  • Indications: Hypofibrinogenemia (e.g., DIC, massive transfusion), Factor XIII deficiency, von Willebrand Disease (vWD) if specific factor concentrates are unavailable.
  • Dose: 1-2 units/10 kg.
  • ⭐

    Cryoprecipitate is the most concentrated source of fibrinogen.

Transfusion Troubles - Reaction Rescue

• Acute Reactions (STOP Transfusion First!)
  • Allergic/Anaphylactic: Urticaria, wheeze. Rx: Antihistamines, epinephrine.
  • AHTR: Fever, hemoglobinuria, shock. Rx: IV fluids, support.
  • FNHTR: Fever, chills. Rx: Antipyretics. Prevent: Leukoreduction.
  • TRALI: Dyspnea, hypoxia, infiltrates (within 6h). Rx: O2, ventilation.
  • TACO: Dyspnea, ↑JVP, edema. Rx: Diuretics, O2.
• Delayed Reactions
  • DHTR: Jaundice, ↓Hb (5-10d).
  • TA-GVHD: Rash, pancytopenia. Prevent: Irradiation.
  • Post-transfusion Purpura: ↓Platelets (~7d).
  • Iron Overload: Chronic. Rx: Chelation.

⭐ TRALI: Leading cause of transfusion mortality. Acute respiratory distress, bilateral pulmonary infiltrates within 6 hrs post-transfusion, not due to circulatory overload.

High‑Yield Points - ⚡ Biggest Takeaways

• PRBCs indicated for symptomatic anemia or Hb < 7 g/dL in stable children.
• Platelets for active bleeding with thrombocytopenia or prophylactically if counts < 10,000-20,000/µL.
• FFP replaces multiple coagulation factors; used in DIC, liver disease, warfarin reversal.
• Cryoprecipitate provides fibrinogen, Factor VIII, vWF; for hypofibrinogenemia, hemophilia A.
• Irradiation of blood products prevents TA-GVHD in immunocompromised individuals.
• Leukoreduction reduces risks of FNHTR, CMV transmission, and HLA alloimmunization.