Overview
Definition:
Transfusion reactions are adverse events occurring during or after blood component therapy, ranging from mild to life-threatening
In pediatrics, they require careful vigilance due to unique physiological considerations and challenges in symptom reporting.
Epidemiology:
The incidence varies by reaction type and blood product, but overall, serious transfusion reactions are rare
Febrile non-hemolytic transfusion reactions (FNHTRs) are the most common in pediatrics
Acute hemolytic reactions are rarer but more severe
Risk is influenced by patient age, transfusion history, and type of blood product transfused.
Clinical Significance:
Recognition and prompt management of transfusion reactions are crucial for patient safety, preventing morbidity and mortality
Understanding the pathophysiology and clinical manifestations helps differentiate between reaction types and guide appropriate intervention, essential for pediatric residents preparing for DNB and NEET SS examinations.
Clinical Presentation
Symptoms:
Fever with or without chills
Pruritus or urticaria
Dyspnea or tachypnea
Hypotension
Back or chest pain
Nausea or vomiting
Hemoglobinuria
Changes in behavior or irritability (especially in neonates and infants).
Signs:
Tachycardia
Tachypnea
Fever
Hypotension
Jaundice (delayed)
Hematuria
Signs of circulatory overload (e.g., crackles, edema)
Petechiae or purpura (in cases of DIC).
Diagnostic Criteria:
No single set of universal diagnostic criteria exists, but diagnosis is based on a temporal association between transfusion and the onset of clinical signs/symptoms, coupled with laboratory investigations to confirm or exclude specific reaction types.
Diagnostic Approach
History Taking:
Detailed history of the transfusion, including product transfused, unit number, infusion rate, and duration
Any prior transfusion reactions
Underlying medical conditions
Recent illnesses or infections
Allergies
Symptoms reported by caregivers or observed by staff.
Physical Examination:
Thorough assessment of vital signs (temperature, heart rate, respiratory rate, blood pressure, oxygen saturation)
Examination for rash, urticaria, angioedema, or signs of respiratory distress
Cardiopulmonary assessment for signs of fluid overload
Assessment for abdominal tenderness or organomegaly.
Investigations:
Immediate: Stop transfusion, maintain IV access, notify blood bank
Blood work: CBC with differential, direct antiglobulin test (DAT), repeat crossmatch, urinalysis for hemoglobinuria, bilirubin (total and direct), coagulation profile (PT, PTT, fibrinogen, D-dimer), blood cultures if infection suspected
Chest X-ray if respiratory symptoms or fluid overload suspected.
Differential Diagnosis:
Sepsis from contaminated blood product
Fluid overload (TACO)
Bacterial contamination of the patient's bloodstream
Allergic reactions unrelated to transfusion
Underlying disease exacerbation
Anaphylaxis from other causes
Fever from non-transfusion related causes.
Management
Initial Management:
IMMEDIATELY STOP THE TRANSFUSION
Maintain a patent intravenous line with normal saline
Assess vital signs and ABCs (Airway, Breathing, Circulation)
Notify the attending physician and the blood bank immediately
Obtain blood and urine samples from the patient.
Medical Management:
Acute Hemolytic Reaction: Supportive care, hydration, diuresis (e.g., furosemide) to maintain urine output
Monitor renal function
Febrile Non-Hemolytic Reaction: Antipyretics (e.g., acetaminophen)
Monitor closely
Allergic Reaction: Antihistamines (e.g., diphenhydramine)
Bronchodilators if bronchospasm
Epinephrine for severe reactions
TRALI: Supportive care, oxygen, mechanical ventilation if needed
TACO: Diuretics, oxygen, supportive care
Anaphylaxis: Epinephrine, corticosteroids, antihistamines.
Surgical Management:
Rarely indicated for transfusion reactions themselves, but may be necessary for managing severe complications like acute kidney injury requiring dialysis or disseminated intravascular coagulation (DIC) requiring specific hematologic interventions.
Supportive Care:
Close monitoring of vital signs and urine output
Fluid management
Oxygen therapy as needed
Renal support if indicated
Management of DIC if present
Psychological support for patient and family.
Complications
Early Complications:
Acute kidney injury (AKI)
Disseminated intravascular coagulation (DIC)
Acute respiratory distress syndrome (ARDS)
Circulatory overload
Hypotension and shock
Hemolysis and jaundice.
Late Complications:
Post-transfusion purpura
Graft-versus-host disease (GVHD - rare in immunocompetent children)
Iron overload (with chronic transfusions).
Prevention Strategies:
Proper patient identification and blood typing/crossmatching
Transfusion of appropriately screened and leukocyte-reduced components
Careful monitoring during transfusion
Use of leukoreduced filters
Patient education regarding symptoms
Appropriate use of irradiated products for at-risk patients.
Prognosis
Factors Affecting Prognosis:
The severity of the reaction
The promptness and appropriateness of management
The patient's underlying medical condition
The type of blood component transfused.
Outcomes:
Most mild reactions (FNHTR, mild allergic) have excellent outcomes with prompt management
Severe reactions like acute hemolytic transfusion reactions or TRALI can lead to significant morbidity or mortality if not managed aggressively.
Follow Up:
Close follow-up is essential, especially after severe reactions, to monitor for resolution of symptoms and assess for any long-term sequelae
Review of transfusion history and strategies for future transfusions is critical.
Key Points
Exam Focus:
Always stop the transfusion immediately when a reaction is suspected
Differentiate between reaction types based on clinical features and initial lab tests
Recognize TRALI vs
TACO
Understand the management of anaphylaxis and hemolytic reactions in pediatric patients.
Clinical Pearls:
In infants and neonates, changes in behavior, unexplained fever, or poor feeding can be the first signs of a transfusion reaction
Always consider bacterial contamination as a cause of fever and rigors during transfusion
Use of prophylactic acetaminophen for FNHTR is common practice but not always effective.
Common Mistakes:
Failing to stop the transfusion promptly
Inadequate workup for a suspected reaction
Misinterpreting fever as solely due to underlying illness without considering transfusion-related causes
Delaying notification of the blood bank.