massive blood transfusion (washout)

Introduction

Replacement of more than one blood volume (10 units of blood) in < 24 hours.

Pathology

• coagulopathy & thrombocytopenia from replacement with erythrocytes & crystalloid (deficiency in platelets & coagulation factors)
• qualitative platelet defect
• diffuse microvascular bleeding from wounds & other traumatized sites
• disseminated intravascular coagulation (may be related to shock)
• systemic fibrinolysis may occur in patients with severe liver disease
• sudden decreases in plasma Ca+2 can occur as a result of infusions of citrated plasma (especially in patients with severe liver disease unable to rapidly clear citrate from circulation)

Clinical manifestations

• hypotension
• hypothermia

Laboratory

• prothrombin time (PT) & aPTT prolonged
• plasma fibrinogen low
• platelet count: mild thrombocytopenia (50,000-100,000/uL)
• arterial blood gas: metabolic acidosis
• monitor for electrolyte disturbances & metabolic alkalosis
  • hypocalcemia, hyperkalemia, hypokalemia
  • basic metabolic panel

Management

• replacement of blood loss with fresh whole blood*
• prophylactic platelet transfusions NOT helpful
• replace specific factors as indicated by laboratory assessment
  • packed red blood cells (RBC)
  • fresh frozen plasma
  • platelets
• use of blood warmers

* generally NOT available

More general terms

• blood transfusion

Additional terms

• disseminated intravascular coagulation (DIC)
• hypocalcemia
• systemic fibrinolysis (fibrinolytic disorder)