• To revise the principles of transfusion, see Principles of transfusion and Consent for transfusion guidelines
• Packed red blood cells (RBC) in SAG-M additive solution, 280 ± 60 mL, Hct 0.5-0.7
• Collected from UK volunteer whole blood donors i.e. allogeneic
• Stored in controlled temperature at 2-6°C for <35 days
• Only store red cells in designated blood fridges
• Allocated RBC routinely derequisitioned (i.e. returned to stock) at 24 hr
• Areas without a satellite fridge collect 1 unit of blood at a time
• except renal dialysis patients and MHP activation

• Use red cells to restore oxygen carrying capacity in patients with anaemia or blood loss where alternative treatments are ineffective or inappropriate
• Base decision to transfuse on the whole clinical picture:
  • cause of anaemia
  • symptom severity
  • underlying co-morbidities
  • chronicity
  • current and historic laboratory parameters
• RBC transfusion is not associated with reduced mortality. Base decision to transfuse patients (with a single unit followed by reassessment) on the need to relieve clinical signs and symptoms of anaemia, alongside the patient’s response to previous transfusions

Acute blood loss with haemodynamic instability/uncontrolled haemorrhage

• Benefit: Save life
• Target Hb: 70-90 g/L (once haemodynamically stable)
• Blood loss of >20-30% (where average circulating blood volume is 70 mL/kg) with on-going bleeding will likely require urgent transfusion
• Use cell salvage where possible to minimise allogeneic transfusion requirements
• See specific guidelines, including Acute upper gastrointestinal haemorrhage guideline and Major haemorrhage pathway

Recoverable anaemia in a haemodynamically stable patient e.g. post op, critical care

• Benefit: improve symptoms of anaemia, potentially reduce mortality 
• Target Hb: 70-90 g/L (once haemodynamically stable)
• Threshold Hb for transfusion: <70 g/L
• Note: Do not transfuse stable patients with iron deficiency anaemia. Give IV iron. See Iron deficiency guideline
• Note: Do not transfuse stable patients with B₁₂ and/or folate deficiency - see Chronic anaemia guideline, B₁₂ deficiency and Folate deficiency guidelines
• Note: No evidence was found to warrant a different approach for patients who are elderly or who have respiratory or cerebrovascular disease - who may also be at increased risk of fluid overload from transfusion
• Note: Use higher threshold of 75g/L in cardiac surgery patients (during and after surgery)

Acute coronary syndrome (ACS)

• Benefit: improve short term outcome
• Target Hb: 80-100 g/L (once haemodynamically stable)
• Threshold Hb for transfusion: <80 g/L
• Note: Transfusion >100 g/L associated with increased mortality

Chronic transfusion dependence e.g. bone marrow failure (MDS, thalassaemia)

• Benefit: improve quality of life, reduce extramedullary haemopoiesis in thalassaemia
• Target Hb: individual to patient (depending on cause and response)
• Threshold Hb for transfusion: start at 80 g/L and adjust as required

Radiotherapy (weak evidence)

• Benefit: improved response to therapy
• Target Hb: individual to patient
• Threshold Hb for transfusion: consider if <100 g/L in cervical cancer and other cancers receiving radiotherapy
• Note: In patients with cancer, RBC transfusion may be associated with an increased risk of in-hospital mortality, plus increased risk of venous and arterial thromboembolic events

Exchange transfusion e.g. sickle cell disease following acute stroke/chest crisis, or before surgery; haemolytic disease of the fetus and newborn (HDFN)

• Benefit: replace red cells and treat/prevent symptoms
• Target Hb: individual to patient
• Threshold Hb for transfusion: n/a
• Note: See regional sickle cell transfusion guidelines or neonatal guidelines 

• Regard each unit of red blood cells transfused as a treatment decision
• Blood transfusion is associated with significant risk
• use alternatives to transfusion wherever possible and appropriate
• Use the minimum number of units required to achieve target Hb/relieve moderate-severe symptoms i.e. single unit transfusion policy
• Patients with acute coronary syndrome (80 g/L), cardiac surgery (75 g/L), orthopaedic surgery and haemato-oncology patients and may require higher targets
• Except in circumstances where patient’s condition is life-threatening, patient must be given time to ask questions and to make a decision to proceed with transfusion
• Always document indication for transfusion and consent in the medical notes

• Treat underlying cause of anaemia e.g. haematinic deficiency (see relevant medical guidelines) 
• Minimise and treat blood loss e.g. surgical techniques, endoscopy, hormonal treatment of heavy menstrual bleeding, anti-fibrinolytics
• Uphold restrictive transfusion thresholds where appropriate, maximise oxygenation and optimise management of underlying medical conditions 
• Use cell salvage to minimise allogeneic transfusion where possible 
• Employ normovolaemic haemodilution/permissive hypotension where appropriate
• Minimise iatrogenic anaemia by reducing phlebotomy and consider use of paediatric bottles

• Each single unit RBC transfused is a treatment decision (except in active bleeding) = SINGLE UNIT TRANSFUSION POLICY 
• Before every transfusion, assess all patients for risk of transfusion associated circulatory overload (TACO) - see TACO checklist below
  
  • manage appropriately e.g. slow infusion rate, diuretic use, increase frequency of observations 
• Prescribe red blood cells (RBC) on fluid prescription of the drug chart (or specific transfusion chart where available)
  
  • dose in units (or mL in low weight patients e.g. <50 kg at high risk of TACO)
  • indicate special blood requirements (SBR) e.g. irradiated, HbS neg, Rh/K matched on prescription or specify 'no SBR' (just as important)
• Specify transfusion rate depending on clinical situation (do not give a range on prescription chart)
  
  • if low risk of TACO, 120 min per unit 
  • if high risk of TACO, 3 hr per unit ± diuretics 
  • if MHP, 'STAT' through blood warmer (i.e. over 5-10 min - rate will depend on bleeding severity)
• In the absence of active bleeding, use minimum number of units required to achieve target Hb taking into account patient size
  
  • 1 unit RBC expected to raise Hb by 10g/L in 70 kg patient (but note 1 unit = 220-340 mL)
  • 4 mL/kg RBC expected to raise Hb by 10g/L (use in adult patients <50 kg)
  • or use online dosage calculator https://www.rcdcalculator.co.uk/

TACO Checklist

• Commence transfusions as soon as possible after component receipt in the clinical area
• Complete transfusion within 4 hr of RBC leaving cold storage 
• In areas without a satellite blood fridge, only one unit of blood per patient to be collected at a time (except renal dialysis patients and MHP activation) 
• Any unused units to be returned (on availability and location system) to the transfusion laboratory (or designated blood fridge) ASAP to avoid wastage
  
  • ideally within 30 min of leaving controlled temperature storage
• Use standard blood giving set with 170-200 micron filter 
• Adhere to standard operating procedure for administration of blood components regarding bedside checks and monitoring frequency 
• Any blood component connected to the patient’s IV access is regarded as 'transfused' for traceability purposes - even if the unit was subsequently (partially) wasted
• Blood warmers to be used if clinically significant cold antibodies, elective/emergency surgery requiring ≥500 mL of fluids including blood components, major haemorrhage 
• Complete transfusion within 4 hr of red blood cells leaving cold storage

• Each single unit RBC transfused is an independent treatment decision 
• Assess every patient clinically after each unit transfused asking; 
  
  1. have symptoms/signs of anaemia resolved? - document severity grade (see Table 1)
  2. is there evidence of fluid overload (TACO)? - document any symptoms/signs
  3. what is the Hb increment after each unit transfused? 
• Note: Check Hb after each unit transfused except in active bleeding, chronically transfused outpatients, or where target threshold cannot realistically be achieved. 
• In active bleeding (haemodynamically stable patients) check Hb increment after maximum 2 unit RBC transfusion to avoid over-transfusion
  
  • note: repeat Hb can be performed from 15 min post transfusion as FBC or blood gas (latter for response assessment only - not initial treatment decision)
• Patients transfused to >20 g/L above target threshold are deemed 'over-transfused'
• Ensure definitive treatment also prescribed e.g. iron supplementation where appropriate

Table 1: Anaemia severity grading score

Document

• Fully document consent for transfusion, efficacy/impact and any complications in medical and nursing notes
• If moderate or severe acute transfusion reaction - complete Datix
• In discharge letter, document any transfusion (including component details, dates and any complications) 
• Specify if definitive treatment also prescribed/given (where appropriate)

• Group O RhD negative blood cells are a finite resource – use only where clinically 
  indicated i.e.
  
  • Group O RhD negative patients
  • major haemorrhage in women of child-bearing potential
  • life-threatening haemorrhage whilst awaiting arrival of group O appropriate red cells
• See major haemorrhage policy

Administration

• Take crossmatch sample before group O red cell administration
• 2-sample rule does not apply in emergency setting
• Switch to group specific red cells as soon as available

Access

• Only staff who have undergone appropriate fridge training can access O RhD negative units (barcode required)
• Hospital specific method of access