Useful For

An unfavorable event in a patient during or following a transfusion of blood products need to be investigated to determine what type of reaction may have occurred, possible causes and what further action, if any, should be taken.

There are several types of transfusion reactions, including but not limited to:

• Hemolytic Transfusion Reaction (HTR)
• Transfusion Related Acute Lung Injury (TRALI)
• Transfusion Associated Circulatory Overload (TACO)
• Allergic Reactions
• Febrile Non-Hemolytic Reactions

Hemolytic Transfusion Reaction (HTR)

Making a diagnosis of HTR can sometimes be difficult. Onset of symptoms may be mild or vague.  In the case of an anesthetized or unconscious patient, manifestation of symptoms is difficult to assess. Whenever an HTR is suspected, the transfusion must be stopped.  Signs and symptoms that may accompamy a HTR include:

• Fever
• Chills
• Chest Pain
• Hypotension
• Nausea
• Flushing
• Dyspnea
• Hemoglobinuria
• Shock
• Generalized Bleeding
• Oliguria or Anuria
• Back Pain
• Pain at Infusion Site

Transfusion Related Acute Lung Injury (TRALI)

TRALI is a syndrome characterized by acute respiratory distress following transfusion. All plasma-containing blood products have been implicated including rare reports of IVIG and cryoprecipitate.  TRALI is associated with a high morbidity with the majority of patients requiring ventilatory support. However, the lung injury is generally transient with PO2 levels returning to pretransfusion levels within 48 - 96 hours and CXR returning to normal within 96 hours.  TRALI is now among the three leading causes of transfusion related fatalities.  Symptoms of TRALI typically develop during, or within 6 hours of a transfusion. Patients present with:

• Rapid onset of dyspnea and tachypnea.
• Possible fever, cyanosis, and hypotension.
• Clinical exam reveals respiratory distress and pulmonary crackles may be present with no signs of congestive heart failure or volume overload.
• CXR shows evidence of bilateral pulmonary edema unassociated with heart failure (non-cardiogenic pulmonary edema), with bilateral patchy infiltrates, which may rapidly progress to complete "white out" indistinguishable from Acute Respiratory Distress Syndrome (ARDS).

If TRALI is suspected notification of United Blood Service is necessary so that donor testing for granulocyte and/ or HLA antibodies can be pursued.

Transfusion Associated Circulatory Overload (TACO)

Transfusion-associated circulatory overload (TACO) is a frequent occurrence, complicating 1-8% of transfusions.  TACO has emerged as a major cause of transfusion morbidity.  Morbidity is significant, as 21% of cases are life-threatening with associated increases in lengths of ICU and hospital stay.  TACO is hydrostatic pulmonary edema precipitated by transfusion. It is characterized by respiratory distress within six hours of transfusion. Both red blood cell (RBC) and plasma-containing blood components may trigger the reaction.  The following may occur during or within 6 hours of transfusion:

• Acute respiratory distress (dyspnea, orthopnea, cough)
• Evidence of positive fluid balance
• Elevated brain natriuretic peptide (BNP)
• Radiographic evidence of pulmonary edema
• Evidence of left heart failure
• Elevated central venous pressure

Allergic Reactions

Allergic reactions are IgE mediated. These reactions are usually attributed to hypersensitivity to soluble allergens found in the transfused blood component.  Allergic reactions typically present as:

• Rash
• Urticaria
• Pruritus
• Indistinguishable on examination from most food or drug allergies

Diphenhydramine is usually effective for relieving pruritus that is associated with hives or a rash. 

Nonhemolytic Febrile Reactions

Nonhemolytic febrile transfusion reactions are usually caused by cytokines from leukocytes in transfused red cell or platelet components.  A nonhemolytic transfusion reaction is a diagnosis of exclusion, because hemolytic and septic reactions can present similarly.  Nonhemolytic febrile transfusion reactions usually present with:

• Fever (elevation of 1º C or 2º F)
• Chills
• Rigors

Febrile, nonhemolytic reactions: Usually, fever resolves in 15-30 minutes without specific treatment.