Recommendations

People have the right to be involved in discussions and make informed decisions about their care, as described in your care.

Making decisions using NICE guidelines explains how we use words to show the strength of our recommendations, and has information about safeguarding, consent and prescribing medicines (including 'off‑label' use).

This guideline contains recommendations about general principles of blood transfusion, and applies to a range of conditions and different settings. It does not make recommendations relating to specific conditions. For more information on what the guideline covers, see the context section.

Some people have religious beliefs that do not allow the transfusion of blood. Specific issues relating to these people have been addressed when reviewing the evidence and writing the recommendations.

Blood transfusion algorithm

Download the PDF here.

1.1 Alternatives to blood transfusion for patients having surgery

Erythropoietin

1.1.1 Do not offer erythropoietin to reduce the need for blood transfusion in patients having surgery, unless:

  • the patient has anaemia and meets the criteria for blood transfusion, but declines it because of religious beliefs or other reasons or

  • the appropriate blood type is not available because of the patient's red cell antibodies.

Intravenous and oral iron

1.1.2 Offer oral iron before and after surgery to patients with iron‑deficiency anaemia.

1.1.3 Consider intravenous iron before or after surgery for patients who:

  • have iron‑deficiency anaemia and cannot tolerate or absorb oral iron, or are unable to adhere to oral iron treatment (see the NICE guideline on medicines adherence)

  • are diagnosed with functional iron deficiency

  • are diagnosed with iron‑deficiency anaemia, and the interval between the diagnosis of anaemia and surgery is predicted to be too short for oral iron to be effective.

1.1.4 For guidance on managing anaemia in patients with chronic kidney disease, see the NICE guideline on anaemia management in chronic kidney disease.

Cell salvage and tranexamic acid

1.1.5 Offer tranexamic acid to adults undergoing surgery who are expected to have at least moderate blood loss (greater than 500 ml).

1.1.6 Consider tranexamic acid for children undergoing surgery who are expected to have at least moderate blood loss (greater than 10% blood volume).

1.1.7 Do not routinely use cell salvage without tranexamic acid.

1.1.8 Consider intra‑operative cell salvage with tranexamic acid for patients who are expected to lose a very high volume of blood (for example in cardiac and complex vascular surgery, major obstetric procedures, and pelvic reconstruction and scoliosis surgery).

1.2 Red blood cells

Thresholds and targets

1.2.1 Use restrictive red blood cell transfusion thresholds for patients who need red blood cell transfusions and who do not:

  • have major haemorrhage or

  • have acute coronary syndrome or

  • need regular blood transfusions for chronic anaemia.

1.2.2 When using a restrictive red blood cell transfusion threshold, consider a threshold of 70 g/litre and a haemoglobin concentration target of 70–90 g/litre after transfusion.

1.2.3 Consider a red blood cell transfusion threshold of 80 g/litre and a haemoglobin concentration target of 80–100 g/litre after transfusion for patients with acute coronary syndrome.

1.2.4 Consider setting individual thresholds and haemoglobin concentration targets for each patient who needs regular blood transfusions for chronic anaemia.

Doses

1.2.5 Consider single‑unit red blood cell transfusions for adults (or equivalent volumes calculated based on body weight for children or adults with low body weight) who do not have active bleeding.

1.2.6 After each single‑unit red blood cell transfusion (or equivalent volumes calculated based on body weight for children or adults with low body weight), clinically reassess and check haemoglobin levels, and give further transfusions if needed.

1.3 Platelets

Thresholds and targets

Patients with thrombocytopenia who are bleeding

1.3.1 Offer platelet transfusions to patients with thrombocytopenia who have clinically significant bleeding (World Health Organization [WHO] grade 2) and a platelet count below 30×109 per litre.

1.3.2 Use higher platelet thresholds (up to a maximum of 100×109 per litre) for patients with thrombocytopenia and either of the following:

  • severe bleeding (WHO grades 3 and 4)

  • bleeding in critical sites, such as the central nervous system (including eyes).

Patients who are not bleeding or having invasive procedures or surgery

1.3.3 Offer prophylactic platelet transfusions to patients with a platelet count below 10×109 per litre who are not bleeding or having invasive procedures or surgery, and who do not have any of the following conditions:

  • chronic bone marrow failure

  • autoimmune thrombocytopenia

  • heparin-induced thrombocytopenia

  • thrombotic thrombocytopenic purpura.

Patients who are having invasive procedures or surgery

1.3.4 Consider prophylactic platelet transfusions to raise the platelet count above 50×109 per litre in patients who are having invasive procedures or surgery.

1.3.5 Consider a higher threshold (for example 50–75×109 per litre) for patients with a high risk of bleeding who are having invasive procedures or surgery, after taking into account:

  • the specific procedure the patient is having

  • the cause of the thrombocytopenia

  • whether the patient's platelet count is falling

  • any coexisting causes of abnormal haemostasis.

1.3.6 Consider prophylactic platelet transfusions to raise the platelet count above 100×109 per litre in patients having surgery in critical sites, such as the central nervous system (including the posterior segment of the eyes).

When prophylactic platelet transfusions are not indicated

1.3.7 Do not routinely offer prophylactic platelet transfusions to patients with any of the following:

  • chronic bone marrow failure

  • autoimmune thrombocytopenia

  • heparin‑induced thrombocytopenia

  • thrombotic thrombocytopenic purpura.

1.3.8 Do not offer prophylactic platelet transfusions to patients having procedures with a low risk of bleeding, such as adults having central venous cannulation or any patients having bone marrow aspiration and trephine biopsy.

Doses

1.3.9 Do not routinely transfuse more than a single dose of platelets.

1.3.10 Only consider giving more than a single dose of platelets in a transfusion for patients with severe thrombocytopenia and bleeding in a critical site, such as the central nervous system (including eyes).

1.3.11 Reassess the patient's clinical condition and check their platelet count after each platelet transfusion, and give further doses if needed.

1.4 Fresh frozen plasma

Thresholds and targets

1.4.1 Only consider fresh frozen plasma transfusion for patients with clinically significant bleeding but without major haemorrhage if they have abnormal coagulation test results (for example, prothrombin time ratio or activated partial thromboplastin time ratio above 1.5).

1.4.2 Do not offer fresh frozen plasma transfusions to correct abnormal coagulation in patients who:

  • are not bleeding (unless they are having invasive procedures or surgery with a risk of clinically significant bleeding)

  • need reversal of a vitamin K antagonist.

1.4.3 Consider prophylactic fresh frozen plasma transfusions for patients with abnormal coagulation who are having invasive procedures or surgery with a risk of clinically significant bleeding.

Doses

1.4.4 Reassess the patient's clinical condition and repeat the coagulation tests after fresh frozen plasma transfusion to ensure that they are getting an adequate dose, and give further doses if needed.

1.5 Cryoprecipitate

Thresholds and targets

1.5.1 Consider cryoprecipitate transfusions for patients without major haemorrhage who have:

  • clinically significant bleeding and

  • a fibrinogen level below 1.5 g/litre.

1.5.2 Do not offer cryoprecipitate transfusions to correct the fibrinogen level in patients who:

  • are not bleeding and

  • are not having invasive procedures or surgery with a risk of clinically significant bleeding.

1.5.3 Consider prophylactic cryoprecipitate transfusions for patients with a fibrinogen level below 1.0 g/litre who are having invasive procedures or surgery with a risk of clinically significant bleeding.

Doses

1.5.4 Use an adult dose of 2 pools when giving cryoprecipitate transfusions (for children, use 5–10 ml/kg up to a maximum of 2 pools).

1.5.5 Reassess the patient's clinical condition, repeat the fibrinogen level measurement and give further doses if needed.

1.6 Prothrombin complex concentrate

Thresholds and targets

1.6.1 Offer immediate prothrombin complex concentrate transfusions for the emergency reversal of warfarin anticoagulation in patients with either:

  • severe bleeding or

  • head injury with suspected intracerebral haemorrhage.

1.6.2 For guidance on reversing anticoagulation treatment in people who have a stroke and a primary intracerebral haemorrhage, see recommendation 1.4.2.8 in the NICE guideline on the initial diagnosis and management of stroke.

1.6.3 Consider immediate prothrombin complex concentrate transfusions to reverse warfarin anticoagulation in patients having emergency surgery, depending on the level of anticoagulation and the bleeding risk.

1.6.4 Monitor the international normalised ratio (INR) to confirm that warfarin anticoagulation has been adequately reversed, and consider further prothrombin complex concentrate.

1.7 Patient safety

Monitoring for acute blood transfusion reactions

1.7.1 Monitor the patient's condition and vital signs before, during and after blood transfusions, to detect acute transfusion reactions that may need immediate investigation and treatment.

1.7.2 Observe patients who are having or have had a blood transfusion in a suitable environment with staff who are able to monitor and manage acute reactions.

Electronic patient identification systems

1.7.3 Consider using a system that electronically identifies patients to improve the safety and efficiency of the blood transfusion process.

1.8 Patient information

1.8.1 Provide verbal and written information to patients who may have or who have had a transfusion, and their family members or carers (as appropriate), explaining:

  • the reason for the transfusion

  • the risks and benefits

  • the transfusion process

  • any transfusion needs specific to them

  • any alternatives that are available, and how they might reduce their need for a transfusion

  • that they are no longer eligible to donate blood

  • that they are encouraged to ask questions.

1.8.2 Document discussions in the patient's notes.

1.8.3 Provide the patient and their GP with copies of the discharge summary or other written communication that explains:

  • the details of any transfusions they had

  • the reasons for the transfusion

  • any adverse events

  • that they are no longer eligible to donate blood.

1.8.4 For guidance on communication and patient‑centred care for adults, see the NICE guideline on patient experience in adult NHS services.

1.9 Blood transfusions for patients with acute upper gastrointestinal bleeding

1.9.1 For guidance on blood transfusions for people with acute upper gastrointestinal bleeding, see section 1.2 in the NICE guideline on acute upper gastrointestinal bleeding.

Terms used in this guideline

Adults, children and young people are defined as:

  • Children: over 1 year to under 16 years.

  • Young people: 16 years to under 18 years. No evidence was found on transfusions specifically for young people. Recommendations for adults in this guideline will generally apply to young people as well, but healthcare professionals should use their clinical judgement on when this is not appropriate for individual patients.

  • Adults: 18 years or older.

Major haemorrhage can be defined as any of the following:

  • The loss of more than 1 blood volume within 24 hours (around 70 ml/kg, or more than 5 litres in a 70 kg adult).

  • A loss of 50% of total blood volume in under 3 hours.

  • Bleeding in excess of 150 ml/minute in adults.

  • As a practical clinical definition, bleeding which leads to:

    • a systolic blood pressure of less than 90 mm/Hg or

    • a heart rate of more than 110 beats per minute in adults.

The modified World Health Organization (WHO) bleeding scale was used to assess bleeding in trials of platelet transfusions. Examples of bleeding at each grade are listed below:

World Health Organization Bleeding Grade

Examples

1

  • Oropharyngeal bleeding, with the total duration of all episodes no more than 30 minutes in the last 24 hours.

  • Epistaxis, with the total duration of all episodes no more than 30 minutes in the last 24 hours.

  • Petechiae of oral mucosa or skin.

  • Purpura up to 2.5 cm (1 inch) in diameter.

  • Spontaneous haematoma in soft tissue or muscle.

  • Positive stool occult blood test.

  • Microscopic haematuria or haemoglobinuria.

  • Abnormal vaginal bleeding (spotting).

2

  • Epistaxis, with the total duration of all episodes over 30 minutes in 24 hours.

  • Purpura over 2.5 cm (1 inch) in diameter.

  • Joint bleeding.

  • Melanotic stool.

  • Haematemesis.

  • Gross/visible haematuria.

  • Abnormal vaginal bleeding (more than spotting).

  • Haemoptysis.

  • Visible blood in body cavity fluid.

  • Retinal bleeding without visual impairment.

  • Bleeding at invasive sites.

3

  • Bleeding needing red blood cell transfusion over routine transfusion needs.

  • Bleeding associated with moderate haemodynamic instability.

4

  • Bleeding associated with severe haemodynamic instability.

  • Fatal bleeding.

  • Central nervous system bleeding on imaging study with or without dysfunction.

You can also see this guideline in the NICE pathway on transfusion.

To find out what NICE has said on topics related to this guideline, see our web page on blood conditions.

  • National Institute for Health and Care Excellence (NICE)