The outcome is significantly different (poor) for anaemic patient:
A META-ANALYSIS (BJS 2015) showed the following: (DOI: 10.1002/bjs.9861)
- Anaemia was associated with increased mortality (OR 2·90, 2·30 to 3·68; I2 = 97 per cent; P < 0·001), acute kidney injury (OR 3·75, 2·95 to 4·76; I2 = 60 per cent; P < 0·001) and infection (OR 1·93, 1·17 to 3·18; I2 = 99 per cent; P = 0·01).
- Among cardiac surgical patients, anaemia was associated with stroke (OR 1·28, 1·06 to 1·55; I2 = 0 per cent; P = 0·009) but not myocardial infarction (OR 1·11, 0·68 to 1·82; I2 = 13 per cent; P = 0·67).
- Anaemia was associated with an increased incidence of red cell transfusion (OR 5·04, 4·12 to 6·17; I2 = 96 per cent; P < 0·001). Similar findings were observed in the cardiac and non-cardiac subgroups.
THEREFORE, the following recommendations applies to anaemic patients undergoing an operation: (DOI: 10.1002/bjs.9898)
- Both anaemia and blood transfusion are independently associated with adverse outcomes.
- Functional iron deficiency (iron restriction due to increased levels of hepcidin) is the most common cause of preoperative anaemia, and should be treated with intravenous iron.
- Intraoperative blood loss can be reduced with antifibrinolytic drugs such as tranexamic acid, and cell salvage should be used.
- A restrictive transfusion practice should be the standard of care after surgery.