Overview
Red blood cells (RBCs)
Red blood cells are usually given over 90 minutes.
Indicated in patients that do not:
- Have major haemorrhage
- Have acute coronary syndrome (ACS)
- Need regular blood transfusions for chronic anaemia
Thresholds and targets:
- Patient without ACS:
- Threshold: 70 g/L
- Target: 70-90 g/L
- Patient with ACS:
- Threshold: 80 g/L
- Target: 80 – 100 g/L
Platelets
Platelets are stored at 20-24°C, making them carry a risk of bacterial contamination and infection compared to other blood products.
If patients have thrombocytopenia and are actively bleeding:
- If platelets are less than 30 x 109/L: offer platelet transfusion
- If severe bleeding/bleeding in critical areas (e.g. CNS, eyes): use higher thresholds up to 100 x 109/L
If patients are having invasive procedures or surgery:
- If platelets are less than 50 x 109/L: offer platelets
- Use higher thresholds if there is a higher risk of bleeding
If patients are not bleeding and are not having invasive procedures or surgery:
- If platelets are less than 10 x 109/L: offer platelet transfusion – do not offer if there any of the following:
- Chronic bone marrow failure
- Autoimmune thrombocytopenia
- Heparin-induced thrombocytopenia (HIT)
- Thrombotic thrombocytopenic purpura (TTP)
Fresh frozen plasma (FFP)
FFP is made through centrifugation and freezing of plasma. It contains coagulation factors such as clotting factors, fibrinogen etc.
FFP is given to patients that have abnormal coagulation results and are bleeding without major haemorrhage (e.g. liver disease, disseminated intravascular coagulation (DIC) etc.)
- The universal donor of FFP is blood from a person with an AB blood group. This is because it does not have any anti-A or anti-B antibodies.
Cryoprecipitate
Cryoprecipitate is made by partially thawing FFP and is generally used in people who have von Willebrand’s disease or people who severely lack fibrin.
It is offered in patients that have significant bleeding and a fibrinogen level below 1.5 g/L.
Prothrombin complex concentrate (PCC)
PCC includes multiple clotting factors such as factors II, VII, IX, and X. It is used for emergency reversal of warfarin or anticoagulation in patients that have severe bleeding or a head injury and suspected intracranial bleeding.
See Warfarin for more detail.
CMV-negative blood
Cytomegalovirus (CMV) can be transmitted by leukocytes in the blood. CMV-negative blood is used in patients who are immunodeficient or neonates whose immune systems are still immature.
CMV-negative blood is collected from people who have not been exposed to CMV in the past. This is usually verified by checking for CMV antibodies.
Most blood products are depleted of leukocytes to remove the risk of CMV transmission.
Irradiated blood
Irradiated blood is blood that has been treated with radiation to prevent Transfusion-Associated Graft-versus-Host Disease (TA-GvHD). The radiation depletes the blood of lymphocytes.
This is important because these lymphocytes can recognise the recipient’s blood as foreign and lead to TA-GvHD which can be dangerous.
See Transfusion-Associated Graft-versus-Host Disease for more information.
Alternatives to blood transfusions
Some patients (e.g. Jehovah’s Witnesses) may have religious objections or other reasons to decline blood tests. Alternative options are:
- Erythropoietin (EPO):
- This is given if the patient has anaemia and meets the criteria for a blood transfusion but declines it due to their beliefs or the appropriate blood type is not available
- Iron deficiencies should be corrected first – this is because RBC synthesis requires sufficient amounts of iron
- IV and oral iron:
- For patients that have iron-deficiency anaemia
- Cell salvage and tranexamic acid:
- This involves the collection of the person’s own blood, filtering, and re-infusing it back into them