Transfusion medicine handbook

7. Adverse Effects of Transfusion

7.11 Transfusion-associated Circulatory Overload

When too much fluid is transfused or the transfusion is too rapid for a patient, fluid overload can lead to systemic and pulmonary venous engorgement. Cardiogenic pulmonary oedema and acute respiratory failure may follow.

The features of transfusion-associated circulatory overload (TACO) include acute respiratory distress, tachycardia, increased blood pressure, evidence of fluid overload, an enlarged cardiac silhouette and new or worsening pulmonary oedema in the chest X-ray. TACO usually occurs within 6 hours of completion of the transfusion. Evidence of fluid overload may include a documented positive fluid balance and/or a clinical response to diuretic therapy. Diagnosis is supported by an elevated serum B-type natriuretic peptide (BNP) or the accompanying N-terminal fragment (NT-pro BNP) to more than 1.5 times the pretransfusion value (if available) and/or an increase in mean arterial pressure or increase pulmonary wedge pressure.

Standard medical treatment includes stopping the transfusion, sitting the patient upright, administering oxygen and diuretic therapy. Where necessary, vasodilator therapy and/or non-invasive ventilatory support with continuous positive airways pressure (CPAP) may be helpful. Venesection can also be considered.

TACO is most commonly seen in patients with low body weight, the elderly, infants or children, those with a history of cardiac, respiratory or renal insufficiency, and in the setting of red cell transfusion for chronic anaemia. Volume overload is a special risk with albumin solutions.

Patients with chronic anaemia are normovolaemic or hypervolaemic and may have signs of cardiac failure before any fluid is infused. Each unit should be given slowly and the patient closely observed. Pre-emptive diuretic therapy may be helpful.