• Red cells have a shelf life of 35 days at 4°C and are supplied as concentrated red cells with PCV between 0.55 and 0.75. Most units in the UK are supplied in 'optimal additive solution', SAG-M*, which allows removal of all the plasma for preparation of other blood components and results in a less viscous product. The volume of a unit of concentrated cells is 280 ± 20mL. With adequate venous access it will flow easily through a standard blood giving set.

• In acute blood loss concentrated RBCs are adequate (whole blood not currently available in practice). Concentrated RBCs allow maintenance of oxygen delivery, and are often infused at the same time as other colloids.

• All blood in UK is leucodepleted at source.

• Irradiated RBCs are indicated to stop transfusion transmitted graft versus host disease e.g. following total body irradiation, bone marrow allografting or therapy with purine analogues (fludarabine, 2-CDA).

• Frozen RBCs similarly have plasma and some other constituents removed. They are expensive to process, store and handle; they must be used within 24h after thawing. Clinical usage is restricted to patients with extremely rare blood groups or with highly problematic blood group alloantibodies.

In autoimmune haemolytic disorders transfusion can be lifesaving as a short term support pending a response to immunosuppression. As a general rule, most otherwise fit adult patients with chronic anaemia will tolerate Hb levels around 9.0-10.0g/dL without major problems. Transfusion therapy is more likely to be needed below this level

0 0

Post a comment