Single unit blood transfusions

This page contains information for clinical and laboratory transfusion staff to support a single unit approach to blood transfusion

Patient blood management strategies are paramount to optimise patients' own red cells and avoid transfusion where possible. However, where transfusion is unavoidable, restrictive Hb thresholds and a single unit approach should be adopted for non-bleeding, stable patients and those not on a chronic transfusion programme.

Transfusing one unit at a time minimises inappropriate transfusion, thereby minimising any serious risks associated with transfusion such as transfusion-associated circulatory overload (TACO).

Giving a single unit blood transfusion

A graphic displaying two blood bags that are crossed out, to show the importance of using a single unit.Single unit transfusions reduce the risk of an adverse reaction and may be suitable for the following adults:

  • Clinically stable
  • Normovolaemic
  • No evidence of clinically significant active bleeding

Clinically reassess the person after each unit has been transfused:

  • Are there any signs or symptoms of transfusion reaction?
  • Have their symptoms of anaemia improved?
  • Re-check haemoglobin levels – is a further unit indicated?
Recommendations

The Patient Blood Management (PBM) recommendations endorsed by NHS England state (2014):

'Transfuse one dose of blood component at a time e.g. one unit of red cells or platelets in non-bleeding patients and reassess the patient clinically and with a further blood count to determine if further transfusion is needed.'

The British Society for Haematology (BSH) administration guidelines 2017 and NICE Blood Transfusion guideline (NG24) 2015 support a single unit transfusion approach.

Single unit transfusion applies to stable, normovolaemic adult in-patients who do not have evidence of clinically significant bleeding.

If you would like more information, please contact your Patient Blood Management Practitioner.