Comment: There were insufficient data of the safety of transfusion in certain clinical subgroups, including acute myocardial infarction, chronic cardiovascular disease, neurological injury/traumatic brain injury, stroke, thrombocytopenia, cancer and haematological malignancies, including chronic bone marrow failure.
A Cochrane review [Abstract] 1 included 48 studies with a total of 21 433 subjects assessing the optimal haemoglobin threshold for the use of red blood cell (RBC) transfusions in anaemic patients (across a range of clinical specialities e.g. surgery, critical care). The restrictive transfusion threshold used a lower haemoglobin level to trigger transfusion (most commonly 7 g/dL or 8 g/dL), and the liberal transfusion threshold uses a higher haemoglobin level to trigger transfusion (most commonly 9 g/dL to 10 g/dL). Restrictive strategies reduced the risk of receiving a RBC transfusion by 41 % across a broad range of clinical specialties (table T1). Overall, restrictive transfusion strategies compared with liberal transfusion strategies did not increase or decrease the risk of 30-day mortality or any of the other outcomes assessed (i.e. cardiac events, myocardial infarction, stroke, thromboembolism, pneumonia, wound infection, or bacteraemia) (table T1).
Outcome | Relative effect(95% CI) | Assumed risk -Control - Liberal transfusion (Hb 9 g/dL to 10 g/dL) | Corresponding risk - Intervention - Restrictive transfusion (Hb 7 g/dL to 8 g/dL) | No of participants(studies) Quality of evidence |
---|---|---|---|---|
People receiving blood transfusions | RR 0.59 (0.53 to 0.66) | 815 / 1000 | 481 / 1000 | 20 057 (42), High |
30-day mortality | RR 0.99 (0.86 to 1.15) | 83 / 1000 | 83 / 1000 | 16 729 (31), High |
Myocardial infarction | RR 1.04 (0.87 to 1.24) | 32 / 1000 | 33 / 1000 | 14 370 (23), High |
Congestive heart failure | RR 0.83 (0.53 to 1.29) | 35 / 1000 | 29 / 1000 | 7 247 (16), Low |
Cerebrovascular accident - stroke | RR 0.84 (0.64 to 1.09) | 17 / 1000 | 14 / 1000 | 13 985 (19), High |
Rebleeding | RR 0.80 (0.59 to 1.09) | 158 / 1000 | 126 / 1000 | 3 412 (8), Moderate |
Infection | RR 0.97 (0.88 to 1.07) | 143 / 1000 | 139 / 1000 | 17 104 (25), High |
Thromboembolism | OR 1.11 (0.65 to 1.88) | 15 / 1000 | 17 / 1000 | 4 201 (13), High |
Date of latest search: 27 May 2016
Primary/Secondary Keywords