SN5 SHORT NOTE 5M

Describe TRALI & TACO in detail.

General Surgery · Final Professional

Two Causes of Post-transfusion Breathlessness

TRALI and TACO are two important causes of acute respiratory distress during or shortly after transfusion that must be distinguished, as their management differs.

Trali VS Taco

Transfusion-related acute lung injury (TRALI) is an immune-mediated, non-cardiogenic pulmonary oedema (from donor antibodies against recipient leucocytes) occurring within ~6 hours — acute hypoxaemia and bilateral infiltrates without fluid overload; managed with respiratory support (it is not treated with diuretics). Transfusion-associated circulatory overload (TACO) is cardiogenic pulmonary oedema from volume overload (especially in the elderly/cardiac/renal patient) — managed by slowing/stopping the transfusion and giving diuretics.

CLINICAL PEARL

Both cause breathlessness after transfusion: TRALI = immune non-cardiogenic lung injury (support, no diuretics); TACO = circulatory overload (diuretics, slow the transfusion). Think TACO in the elderly/cardiac patient given fluid quickly.

Recognising the Difference

Distinguishing TRALI from TACO at the bedside can be difficult because both present as breathlessness and hypoxaemia with pulmonary infiltrates during or soon after transfusion, but several features help: TACO tends to occur in the patient with limited cardiac or renal reserve given a large or rapid volume, is accompanied by signs of fluid overload such as hypertension and a raised jugular venous pressure, and responds to diuretics and slowing the transfusion; TRALI occurs without overload, often with hypotension and fever, and requires supportive respiratory care rather than diuresis. Getting the distinction right matters because the treatments — removing fluid versus supporting the lungs — are opposite.

CLINICAL PEARL

Separate the two by their mechanism and treatment: TACO is overload in the cardiac/elderly patient, treated with diuretics and by slowing the transfusion, whereas TRALI is immune lung injury without overload, treated with respiratory support and not diuretics.

In Brief

In short, treat overload by removing fluid and lung injury by supporting the lungs — opposite treatments for a similar-looking problem.

Volume status separates the two — treatment is opposite.

Feature	TRALI	TACO
Mechanism	Donor antibodies, immune lung injury	Volume overload
Onset	Within 6 hours	During or soon after
Jugular venous pressure	Normal or low	Raised
Blood pressure	Often hypotensive	Often hypertensive
Response to diuretic	Poor	Good
Management	Supportive, ventilation	Diuretics, stop transfusion

KEY POINT

Key points TO remember

TRALI & TACO: acute respiratory distress during/after transfusion — must be distinguished.
TRALI: immune non-cardiogenic pulmonary oedema (donor antileucocyte antibodies), < ~6 h — respiratory support, no diuretics.
TACO: cardiogenic pulmonary oedema from volume overload (elderly/cardiac) — diuretics, slow/stop transfusion.

EXAM TIP

Sources: Morgan & Mikhail’s Clinical Anesthesiology; Miller’s Anesthesia; Ajay Yadav’s Short Textbook of Anaesthesia.

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