When is total blood transfusion indicated in severe dengue?

Total Blood Transfusion in Severe Dengue

Total blood transfusion is indicated in severe dengue when there is significant bleeding that causes hemodynamic instability or when there is evidence of severe hemorrhage requiring immediate intervention to prevent morbidity and mortality.

Indications for Blood Transfusion in Severe Dengue

• Blood transfusion should be administered when patients with severe dengue present with significant bleeding that cannot be controlled by other means 1
• For patients with persistent tissue hypoperfusion despite adequate fluid resuscitation, blood transfusion along with vasopressors such as dopamine or epinephrine may be required 1, 2
• Transfusion is necessary in cases where bleeding leads to hemodynamic instability, as evidenced by hypotension or narrow pulse pressure (signs of dengue shock syndrome) 1, 3

Risk Factors for Severe Hemorrhage in Dengue

• Prolonged duration of shock is a significant risk factor for severe hemorrhage (OR 2.11; 95% CI 1.13-3.92) 4
• Low-normal hematocrit at the time of shock is associated with increased risk of severe hemorrhage (OR 0.72; 95% CI 0.55-0.95) 4
• Warning signs that may precede severe hemorrhage include:
  • Persistent vomiting
  • Severe abdominal pain
  • Lethargy or restlessness
  • Mucosal bleeding
  • Rising hematocrit with rapidly falling platelet count 1, 2

Blood Component Selection and Administration

• For significant bleeding in dengue patients, packed red blood cells should be the primary component for transfusion 5
• Fresh frozen plasma (FFP) may be required in patients with coagulopathy, particularly if fibrinogen levels are < 1 g/L or if PT/aPTT is > 1.5 times normal 6
• Despite severe thrombocytopenia being common in dengue, prophylactic platelet transfusion has not been shown to be effective in preventing bleeding in adult patients with uncomplicated dengue infection 7
• For patients with active bleeding and thrombocytopenia, platelet transfusions may be considered, but their survival is very short in shock cases (few hours to one day) 8

Monitoring During Transfusion

• During blood transfusion, careful monitoring of the following is essential:
  • Vital signs
  • Clinical indicators of adequate tissue perfusion (normal capillary refill time, absence of skin mottling, warm extremities)
  • Urine output (target >0.5 mL/kg/hour)
  • Serial hematocrit and platelet counts 3, 2

Management of Coagulopathy

• If coagulopathy is established (fibrinogen < 1 g/L or PT/aPTT > 1.5 times normal), more than 15 mL/kg of FFP may be required 6
• For rapid fibrinogen replacement, fibrinogen concentrate (30-60 mg/kg) or cryoprecipitate is more effective than FFP 6
• A minimum target platelet count of 75 × 10^9/L is appropriate in the clinical situation of severe bleeding 6

Pitfalls to Avoid

• Avoid excessive fluid administration, which can worsen pulmonary edema, particularly during the recovery phase of dengue 3, 2
• Do not delay fluid resuscitation in patients showing signs of shock 1, 2
• Avoid using aspirin or NSAIDs under any circumstances due to increased bleeding risk 1, 2
• Do not rely solely on platelet counts to predict bleeding risk, as studies have shown that platelet counts are not predictive of bleeding in severe dengue infections 4
• Avoid routine prophylactic platelet transfusion for severe thrombocytopenia without bleeding, as this has not been shown to prevent bleeding in adult dengue patients 7

Special Considerations

• In patients with dengue shock syndrome and heart failure, careful fluid management is crucial to prevent fluid overload while ensuring adequate tissue perfusion 3
• For patients with decreased urine output, careful monitoring of fluid intake and output, vital signs, body weight, and clinical signs of perfusion and congestion is essential 3
• In hospitals where treatment of massive hemorrhage is frequent, locally developed shock packs may be helpful 6