Anaemia, transfusion and transfusion reactions

This is symptomatic severe anaemia on a background of an upper gastrointestinal bleed, with ischaemic heart disease as the key modifier of the transfusion strategy.^[1]

(a) Transfusion strategy — restrictive, FOCUS-style. FOCUS randomised high-cardiovascular-risk hip-fracture patients to a liberal haemoglobin threshold of 10 g/dL versus a restrictive strategy (symptoms of anaemia or haemoglobin below 8 g/dL). The primary outcome was 35.2 versus 34.7 per cent (odds ratio 1.01) — no benefit of the liberal arm.^[1] ED teaching often uses 80 g/L as that restrictive arm, not a licence to transfuse to 100 g/L. Give one unit at a time and recheck.

(b) The pre-transfusion steps and monitoring. Group and screen to establish the ABO and the RhD group and to detect clinically significant antibodies; crossmatch to confirm compatibility. Obtain informed consent — the indication, the common risks (febrile, allergic, TACO) and the rare serious risks (TRALI, haemolytic), and the option to decline.^[4] Perform the bedside two-identifier check — the patient's name and date of birth against the unit label, the unit number, the blood group and the expiry; inspect the unit. This check prevents the acute haemolytic reaction, which haemovigilance traces to process error. Give the unit slowly in this elderly cardiac patient and consider a diuretic: TACO risk rises with transfusion speed and volume and with cardiorenal comorbidity.^[3] Monitor during the unit; acute reactions occur during or within 24 hours.^[4]

(c) The most likely diagnosis is TACO — transfusion-associated circulatory overload. Dyspnoea, tachypnoea, hypoxia, hypertension and bilateral crackles during the unit is classic TACO; hypertension and fluid overload separate it from TRALI. TACO is the leading cause of reaction-related death.^[3] Immediate management: STOP the transfusion and keep the IV line open with saline; sit the patient upright; give high-flow oxygen; give a loop diuretic; consider non-invasive ventilation if hypoxia does not resolve; return the unit and fresh samples to the blood bank; report to haemovigilance. The one reaction to distinguish it from is TRALI — post-transfusion pulmonary oedema without overload, often hypotensive; Vlaar 2019 requires reporting so TACO and TRALI can be classified.^[2]