Transfusion-Associated Circulatory Overload (TACO)

Definition

Pulmonary oedema or respiratory compromise due to volume overload – develops within 12 hours of transfusion.

Can occur after transfusion of relatively small volumes if there are patient risk factors.

Frequency

Rare (≥1 in 10,000 to <1 in 1,000), however it is thought to be under-reported.

TACO is the leading cause of morbidity and mortality related to transfusion.

Reducing the risk

Ideally, all patients (particularly those >50 years) should have a TACO risk assessment before transfusion.

Mitigating measures include:

• Prescribing by volume (mL) rather than in units – this is essential in neonatal/paediatric patients
• Use of diuretics
• Transfusing slowly with closer monitoring

Further information and resources

Serious Hazards of Transfusion (SHOT) educational resources:

• SHOT TACO pre-transfusion risk assessment
• SHOT TACO cumulative data