Transfusion-related Acute Lung Injury (TRALI)

This is an acute (<24 hours), immunological transfusion reaction.

When to suspect this adverse reaction?

Acute onset of fever, chills, dyspnoea, tachypnoea, tachycardia, hypotension, hypoxaemia and noncardiogenic bilateral pulmonary oedema leading to respiratory failure during or within 6 hours of transfusion.

TRALI has been implicated in transfusion of unfractionated plasma-containing components (red cells, platelets and plasma).(1,3)

The true incidence is unknown but variably reported between 1:1200 to 1:190 000 transfusions(1) with estimates around 1:10 000 most commonly reported. TRALI is thought to be the most common cause of transfusion-associated fatalities.(2,3)

Usual causes?

The most widely held pathogenesis theory is that passive transfer of human leucocyte antigen (HLA) or human neutrophil antigen (HNA) antibodies found in the donor’s plasma are directed against the recipient’s leucocyte antigen.(1,2,3)

The antigen-antibody reaction activates neutrophils in the lung microcirculation, releasing oxidases and proteases that damage blood vessels and make them leak.

Biological response modifiers, such as biologically active lipids can accumulate in some cellular components during storage and may also induce TRALI in susceptible patients.(2,3)


TRALI has many clinical features in common with fluid overload or cardiogenic pulmonary oedema and careful clinical assessment is required.

Acute haemolytic reaction or transfusion associated sepsis may have similar initial clinical findings. Direct antiglobulin test (DAT), blood count and repeat ABO grouping may be indicated.

Chest X-ray will show bilateral interstitial infiltrates.

Once TRALI is clinically suspected, test the donor and recipient serum for HLA and HNA antibodies and perform an HLA type on the recipient as demonstration of these antibodies supports diagnosis. TRALI testing is specialised. Please contact Lifeblood.

  • Observations and symptoms and time of onset of symptoms; and
  • Management of suspected TRALI.

A Lifeblood doctor may contact you for further clarification.

Blood samples labelled "TRALI investigations" should be sent at room temperature to the nearest tissue typing laboratory. These are

  • Patient pre-transfusion serum and
  • Patient post-transfusion samples: 10mL serum and 20mL EDTA or ACD.



Stop transfusion immediately and follow other steps for managing suspected transfusion reactions.

Provide cardiovascular and airway support. Administer supplemental oxygen and employ ventilation as necessary. Diuretics are not beneficial.

This may become a medical emergency; support blood pressure and maintain an open airway.

Notify your Transfusion Service Provider to contact Lifeblood so we can quarantine and test related components from the same donor and prevent TRALI in other recipients.

Reducing the risk of antibody-mediated TRALI

To reduce the risk of antibody-mediated TRALI, donors with a possibility of having HLA or HNA antibodies either because of a history of pregnancy or transfusion are not used for plasma products or apheresis platelets.

Two significant changes Lifeblood has made as part of its TRALI Risk Reduction Strategy are:


1. Male-only plasma

Only blood or plasma from male donors is used in the manufacture of clinical plasma products such as FFP or cryoprecipitate.

This stratagem was first introduced in 2007 and since July 2012, 100% of FFP and cryoprecipitate issued by Lifeblood has come from male donors.

2. Apheresis platelets collected from male and nulligravida female donors

To further reduce the TRALI risk associated with apheresis platelets Lifeblood has moved to a plateletpheresis panel comprised of male donors and female donors who have never been pregnant (nulligravida).

This change was introduced during the 2014/15 financial year and since July 2016 100% of apheresis platelets issued by Lifeblood have been from male or nulligravida female donors.


  1. Mazzei CA, Popovsky MA, Kopko PM. Non-infectious complications of blood transfusion. Chapter 27, AABB Technical Manual, 18th edition. AABB, Bethesda, 2014.
  2. Callum JL, Lin Y, Pinkerton PH, Karkouti K, Pendergrast JM, Robitaile N et al. Chapter 5, Transfusion Reactions. Bloody Easy 3: Blood Transfusions, Blood Alternatives and Transfusion Reactions: A Guide to Transfusion Medicine, 3rd edition. Canada: Ontario Regional Blood Coordinating Network, 2011. [cited 2012 Sep 13]. Available from:
  3. Popovsky M (ed). Transfusion reactions, 4th edition. AABB Press, Bethesda, 2012.