Transfusion-Related Complications

Classification & Initial Signs - Red Alert Signals

Classification:

Initial Signs (Red Alert Signals):

• Fever (Temp ↑ >1°C or >38°C), chills/rigors (Most common)
• Hypotension (SBP ↓ >30mmHg), tachycardia (HR ↑ >20bpm)
• Respiratory distress: dyspnea, tachypnea, hypoxia
• Hemoglobinuria (red/dark urine), oliguria
• Skin: Urticaria, rash, pruritus, flushing
• Pain: Chest, back, flank, infusion site
• Nausea/Vomiting
• Anxiety, sense of impending doom
• Under Anesthesia: Unexplained hypotension, hemoglobinuria, diffuse oozing.

⭐ Fever is the most common sign of a transfusion reaction. In anesthetized patients, unexplained hypotension or hemoglobinuria may be the first sign of Acute Hemolytic Transfusion Reaction (AHTR).

Acute Immune Reactions - Rapid Response Havoc

Immediate, antibody-mediated responses to transfused blood components. Require prompt recognition and intervention.

• Acute Hemolytic Transfusion Reaction (AHTR)
  • Cause: ABO incompatibility (IgM); intravascular hemolysis.
  • Sx: Fever, chills, hypotension, hemoglobinuria, flank pain, DIC. Under GA: unexplained hypotension, oozing.
  • 📌 Mnemonic: Hemolysis Alters Vitals Output Clotting (HAVOC)

• Febrile Non-Hemolytic (FNHTR)
  • Cause: Anti-leukocyte Abs or cytokines.
  • Sx: Temp ↑ ≥ 1°C, chills.
  • Tx: Stop, antipyretics. Prevent: Leukoreduction.
• Allergic & Anaphylactic Reactions
  • Urticarial: Hives, pruritus. Tx: Antihistamines.
  • Anaphylaxis: Severe hypotension, bronchospasm. IgA deficiency risk. Tx: Epinephrine, steroids.

⭐ AHTR is the most feared acute reaction, often due to clerical error leading to ABO incompatibility.

Delayed & Non-Immune Issues - Slow Burn & Sneaky Foes

• Delayed Hemolytic Transfusion Reaction (DHTR)
  • Onset: >24h (typ. 3-30d)
  • Cause: Anamnestic Ab (Kidd, Duffy, Kell) to RBCs
  • Sx: Mild jaundice, fever, unexpected ↓Hb, +DAT
• Transfusion-Associated Graft-vs-Host Disease (TA-GVHD)
  • Onset: 1-2w; highly fatal (mortality >90%)
  • Cause: Donor T-lymphocytes attack recipient tissues
  • Sx: Rash, fever, diarrhea, pancytopenia, ↑LFTs

  ⭐ TA-GVHD: Prevent with irradiated blood for at-risk (immunocompromised, relative donors, HLA-matched).

• Post-Transfusion Purpura (PTP)
  • Onset: 5-10d post-transfusion
  • Cause: Alloantibodies to platelet antigens (usu. HPA-1a)
  • Sx: Severe thrombocytopenia (plt <10,000/µL), bleeding
• Iron Overload (Transfusional Hemosiderosis)
  • Cause: Chronic transfusions (1 unit ≈ 200-250mg Fe)
  • Effects: Cardiac, hepatic, endocrine dysfunction
  • Tx: Iron chelation
• Transfusion-Transmitted Infections (TTIs)
  • Viral: HBV, HCV, HIV (window period risk; screening ↓ risk)
  • Parasitic: Malaria, Babesiosis (region-dependent)

Massive Transfusion & Prevention - The Big Pour Fixes

Definition: >10U pRBCs/24h, or >1 blood vol/24h, or >50% blood vol/4h. 📌 Risk: "Lethal Triad" (Hypothermia, Acidosis, Coagulopathy).

• Key Complications & Management:
  • Hypothermia: ↓Coagulation. Warm fluids/blood.
  • Acidosis: ↓Myocardial function. Correct cause.
  • Coagulopathy: Dilutional. Use 1:1:1 (pRBC:FFP:PLT).
  • Hypocalcemia (Citrate): Arrhythmias. Give $Ca^{2+}$ (e.g., 1g CaCl2 / 4-6U pRBCs).
  • Hyperkalemia (Stored blood): Arrhythmias. Monitor, Rx for $K^{+}$.
  • ↓2,3-DPG: Left shift ODC.
• Damage Control Resuscitation (DCR) Principles:
  • Permissive hypotension (SBP 80-90 mmHg, no TBI).
  • Monitor: Temp, ABG, $Ca^{2+}$, $K^{+}$, Coags (TEG/ROTEM).
  • TXA: 1g load, then 1g/8h.

⭐ A target ratio of platelets:FFP:RBCs of 1:1:1 in massive transfusion is associated with improved 6-hour and 24-hour survival in trauma patients.

High‑Yield Points - ⚡ Biggest Takeaways

• AHTR: ABO incompatibility causes fever, chills, hemoglobinuria, DIC. Stop transfusion immediately.
• FNHTR: Most common reaction; cytokines from donor WBCs. Prevent with leukoreduction.
• TRALI: Non-cardiogenic pulmonary edema within 6 hours; donor antibodies. Leading transfusion mortality.
• TACO: Cardiogenic pulmonary edema from volume overload. Manage with diuretics, slow transfusion.
• Massive Transfusion: Risks: hypothermia, dilutional coagulopathy, hypocalcemia (citrate toxicity), hyperkalemia.
• Allergic Reactions: Urticaria common (antihistamines); anaphylaxis rare (epinephrine), potentially fatal.