Rosen & Barkin's 5-Minute Emergency Medicine Consult (724 page)

• Mortality and morbidity correlate with amount of incompatible blood transfused (symptoms can occur with exposure to as little as 5–20 mL)
  
• Occurs immediately from:
  
  • ABO incompatibility
    
  • Blood type identification error
    
  • Incompatible transfused cells immediately destroyed by antibodies
    
• Intravascular hemolysis causing activation of coagulation system, leading to inflammation, shock, and DIC
  
• Mediators (cytokines) released during inflammatory response
  
• Renal failure:
  
  • Cytokines cause local release of endothelin in kidney, causing vasoconstriction.
    
  • Leads to parenchymal ischemia and acute renal failure
    
• Respiratory failure owing to pulmonary edema/adult ARDS:
  
  • Free hemoglobin (Hb) causes vasoconstriction in pulmonary vasculature.
    

• Hemolysis because of Rh incompatibility:
  
  • Mild, self-limiting
    
  • 1:200 U transfused
    
• Febrile nonhemolytic transfusion reaction:
  
  • Most common transfusion reaction, diagnosis of exclusion.
    
  • Temperature increases at least 1°C with chills within 6 hr
    
  • Antigen–antibody reaction to transfused blood components (WBCs, platelets, plasma)
    
  • Usually mild
    
  • Occurs more often with multiparous women or multiple transfusions
    
  • Recurs in 15% of patients
    
  • Acetaminophen may be used prophylactically; its use as premedication is controversial, though not harmful.
    
• Allergic transfusion reaction:
  
  • Occurs in 1% of transfusions
    
  • Usually seen with immunoglobulin A (IgA)–deficient patients
    
  • Urticaria alone is not a reason to stop transfusion.
    
  • Antihistamine may be used as therapy or prophylactically.
    
• Premedicating with acetaminophen and diphenhydramine found to have no effect on incidence of transfusion reaction compared with placebo in some trials.
  

• Infection:
  
  • HIV, hepatitis B, hepatitis C
    
    • Blood screened for viruses
      
    • Blood treated to inactivate viruses
      
    • Blood donors with recent history of travel or poor health are deferred from donating.
      
• Delayed extravascular hemolytic reaction:
  
  • Occurs 7–10 days after transfusion
    
  • Antigen–antibody reaction that develops after transfusion
    
  • Coombs test positive
    
  • Usually asymptomatic
    
  • Blood bank analysis detects antibody
    
• Electrolyte imbalance:
  
  • Hypocalcemia: Calcium binds to citrate
    
  • Hyper/hypokalemia: Citrate metabolized to bicarbonate, which drives potassium intracellularly; prolonged storage of blood may cause hemolysis and hyperkalemia
    
• Graft-versus-host disease:
  
  • Fatal in >90%
    
  • Immunologically competent lymphocytes transfused into immunocompetent host
    
  • Host unable to destroy new WBCs
    
  • Donor WBCs recognize host as foreign and attack host’s tissues.
    
• Anaphylactic reaction:
  
  • Can occur with <10 mL of exposure
    
  • Generalized flushing, urticaria, laryngeal edema, bronchospasm, profound hypotension, shock, or cardiac arrest.
    
  • Treat with subcutaneous epinephrine, supportive hemodynamic and respiratory care.
    
• TRALI:
  
  • Symptoms typically begin with 6 hr of transfusion.
    
  • Acute onset of respiratory distress, bilateral pulmonary edema, fever, tachycardia, hypotension, with normal cardiac function
    
  • 3rd most common cause of fatal transfusion
    
  • Difficult to distinguish from ARDS and TACO; often misdiagnosed and underreported
    
  • Provide supportive care.
    
  • Disease is typically self-limited within 96 hr.
    
  • Mortality is 5–10%.
    
  • Diuretics contraindicated
    

Blood can be transfused through 22G peripheral catheter under pressure (but <300 mm Hg) with minimal hemolysis.

DIAGNOSIS

• General:
  
  • Fevers
    
  • Chills
    
  • Burning at infusion site
    
  • Urticaria/pruritus/skin erythema
    
• Pulmonary:
  
  • Dyspnea
    
  • Bronchospasm
    
  • Respiratory distress/failure
    
• Cardiovascular:
  
  • Tachycardia
    
  • Hypotension
    
  • Substernal chest pain/tightness
    
• GI:
  
  • Nausea
    
  • Vomiting
    
  • Diarrhea
    
• Hematologic:
  
  • Bleeding
    
  • Hemoglobinuria
    
  • Oozing from surgical wounds
    
  • Jaundice
    
  • DIC
    
• Miscellaneous:
  
  • Low back pain
    
  • Renal failure (oliguria/anuria)
    
  • Classic triad of fever, flank pain, and red-brown urine of acute hemolytic reactions is rarely seen.
    

• Recognize clinical findings of transfusion reaction.
  
• Recheck identifying information of blood and patient compatibility.
  
• Recognize evidence of hypotension/shock, severe respiratory distress, sepsis, fever, and urticaria; intervene appropriately.
  

• CBC
  
• Electrolytes, BUN, creatinine, glucose:
  
  • For electrolyte abnormalities
    
• PT, PTT
  
• Serum calcium
  
• Fibrinogen, fibrin degradation products
  
• Bilirubin (direct/indirect)
  
• Coombs test
  
• Hemoglobinemia:
  
  • Pink or red supernatant of plasma or serum indicates hemolysis.
    
• Urinalysis:
  
  • Hemoglobinuria: Dipstick-positive blood without RBCs on micro
    
• Lab findings indicating hemolysis:
  
  • Thrombocytopenia (<100,000)
    
  • Fibrinogenopenia (<150 mg/L)
    
  • Fibrin degradation products
    
  • Prolonged activated PTT (aPTT)
    
  • Spherocytosis
    
• Lab findings indicating hemolysis due to Rh incompatibility:
  
  • Positive Coombs test
    
  • Elevated indirect bilirubin
    
  • Post-transfusion Hb/hematocrit not showing expected rise
    

Chest radiograph: Diffuse patchy infiltrates without cardiomegaly if TRALI.

ECG for dysrhythmia, sign of electrolyte abnormality

• Sepsis
  
• Anaphylaxis/allergic reaction to medication
  

TREATMENT

Routine stabilization

• Immediately stop infusion:
  
  • Severity of reaction proportional to amount of blood transfused
    
• ABCs
  
• Supplemental oxygen—intubation and mechanical ventilation if needed
  
• Recheck blood-identifying information—patient’s bracelet, blood labels, call blood bank
  

• Hypotension:
  
  • 0.9% normal saline (NS) hydration with 2 large-bore IVs
    
  • Avoid Ringer lactate or solutions containing dextrose.
    
  • Trendelenburg position
    
  • Dopamine
    
• Prevention of renal failure:
  
  • Maintain urine output of 1 mL/kg/h
    
  • Adequate hydration
    
  • Furosemide or mannitol if oliguric
    
  • Dopamine infusion at 2 μg/kg/min
    
• Febrile reactions:
  
  • Antipyretics (acetaminophen/nonsteroidal anti-inflammatory drugs [NSAIDs])
    
  • Antihistamine (diphenhydramine + ranitidine) IV
    
  • Steroids (methylprednisolone)
    
• Allergic reactions:
  
  • Antihistamine (diphenhydramine + ranitidine) IV
    
  • Epinephrine for respiratory symptoms
    
  • Steroids (methylprednisolone)
    
• Redraw blood sample for repeat ABO/Rh typing, direct antiglobulin testing.
  
• Foley catheter to monitor urine output
  
• Replenish calcium if hypocalcemia develops.
  
• Treat DIC
  

• Calcium gluconate: 10 mL of 10% (peds: 100 mg/kg/dose) solution slow IV push
  
• Dopamine: 2–20 μg/kg/min IV
  
• Diphenhydramine: 25–50 mg (peds: 1.25 mg/kg) IV or PO
  
• Ranitidine: 50 mg IV (peds: 1–2 mg/kg/dose max. 50 mg)
  
• Epinephrine (1 in 1,000): 0.3–0.5 mL (peds: 0.01 mL/kg) SC
  
• Methylprednisolone: 125 mg (peds: 2 mg/kg) IV
  

FOLLOW-UP

• Acute hemolytic transfusion reaction, pulmonary complications, anaphylaxis, sepsis:
  
  • Require ICU monitoring
    
• Delayed hemolytic transfusion reactions for evaluation/treatment
  
• Electrolyte abnormalities requiring cardiac monitoring
  

Uncomplicated febrile or allergic reaction

• Blood transfusion is substantially over utilized and has significant associated risk, such as transfusion reactions, transmission of pathogens, and immune suppression.
  
• Maintaining body temperature during massive transfusion is crucial to correcting coagulopathy.
  
• Failure to properly compare patient identification to labeling on blood or failure to wait for fully cross-matched blood carries significant risks.
  
• Suspect acute intravascular hemolysis if patient develops hypotension, dark urine, or oozing from IV or other puncture sites.