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ALL / Haematology
Blood products
Blood products
Blood components
Whole blood is usually separated into components, allowing the specific component required by the patient to be transfused. Whole blood is not routinely used in UK civilian practice.
| Component | Key points |
|---|---|
| Red cells in additive solution (SAG-M) |
|
| Platelets |
|
| Fresh frozen plasma |
|
| Cryoprecipitate |
|
Compatibility testing
| Component | Compatibility requirements |
|---|---|
| Red cells | Crossmatching is required. ABO-compatible red cells must be selected and units must lack any antigen corresponding to a clinically significant recipient antibody. |
| Platelets | Not routinely crossmatched. ABO-identical platelets are preferred but ABO-non-identical platelets may be used when necessary. RhD-compatible platelets are preferred for RhD-negative girls and women of childbearing potential; anti-D immunoglobulin should be considered if RhD-positive platelets are given. |
| Fresh frozen plasma | Not crossmatched, but ABO-compatible plasma should be selected. RhD matching and anti-D prophylaxis are not required. |
| Cryoprecipitate | Not crossmatched. ABO-compatible cryoprecipitate is preferred, although suitably selected ABO-non-identical cryoprecipitate may be used in adults when necessary. RhD matching is not required. |
CMV-seronegative blood components
All UK red-cell and platelet components are routinely leucodepleted. CMV-seronegative red cells and platelets are reserved for:
- intrauterine transfusions
- neonates up to 28 days after the expected date of delivery
- elective transfusions during pregnancy, but not during labour or delivery
- CMV-seronegative patients receiving granulocyte transfusions, as granulocytes cannot be leucodepleted
CMV-seronegative components are not routinely required for haematopoietic stem-cell or solid-organ transplant recipients. Leucodepleted red cells and platelets are considered sufficient, alongside appropriate CMV monitoring. In an emergency during pregnancy, leucodepleted components should not be delayed while CMV-seronegative components are sourced.
Cell salvage
Cell salvage is a form of autologous transfusion in which blood lost during or after surgery is collected and returned to the same patient.
Intraoperative cell-salvage devices:
- collect shed blood into an anticoagulated reservoir
- separate and wash the red cells
- resuspend the red cells in sodium chloride 0.9% before reinfusion
- remove most plasma, platelets, coagulation factors and contaminants
Unwashed, filtered postoperative salvage systems may also be used in selected settings.
Cell salvage should be considered when blood loss is expected to exceed 500 mL or when it is likely to reduce exposure to donor red cells. It may be acceptable to Jehovah's Witnesses, but individual wishes must be discussed and documented before surgery.
Malignancy and infection are not absolute contraindications. The risks and benefits should be assessed individually, specific consent obtained and a leucocyte-depletion filter considered when salvaged blood is reinfused.
Warfarin reversal for emergency surgery or major bleeding
1. Stop warfarin and check the INR.
2. If surgery can be delayed for 6–8 hours:
- give intravenous vitamin K, typically 5 mg
- recheck the INR before surgery
3. If surgery cannot be delayed, or there is major or life-threatening bleeding:
- give four-factor prothrombin complex concentrate (PCC), for example Beriplex or Octaplex
- give intravenous vitamin K at the same time to sustain reversal
- PCC contains factors II, VII, IX and X and produces rapid reversal
- the PCC dose depends on the presenting INR, body weight and local protocol; doses are generally 25–50 units/kg
- recheck the INR after administration
Fresh frozen plasma is not recommended for routine warfarin reversal because PCC acts more rapidly, achieves more reliable correction and avoids the large transfusion volume required with plasma.
+PassMedicine Notes
Blood components
Whole blood is usually separated into components, allowing the specific component required by the patient to be transfused. Whole blood is not routinely used in UK civilian practice.
Component_Key points| Red cells in additive solution (SAG-M)_- The standard red-cell component used in the UK.
- Most plasma is removed and replaced with saline, adenine, glucose and mannitol.
- Used to increase oxygen-carrying capacity in symptomatic anaemia or blood loss.
- A unit usually has a volume of 220–340 mL and contains no functional platelets or coagulation factors.
- In adults who are not actively bleeding, consider transfusing one unit followed by clinical and haemoglobin reassessment.|
- May be pooled from four whole-blood donations or collected from a single donor by apheresis.
- Used to prevent or treat bleeding caused by thrombocytopenia or platelet dysfunction.
- One pooled unit or one apheresis unit constitutes one adult therapeutic dose.
- Pooled and apheresis platelets are generally clinically equivalent.|
- Plasma frozen soon after collection to preserve coagulation factors.
- Contains all coagulation factors, including fibrinogen.
- A unit usually has a volume of approximately 250 mL.
- Used for clinically significant bleeding associated with multiple coagulation-factor deficiencies, for example in major haemorrhage, disseminated intravascular coagulation or severe liver disease.
- Also used as replacement fluid during plasma exchange for thrombotic thrombocytopenic purpura.
- A typical initial adult dose is 15 mL/kg, followed by clinical and coagulation-test reassessment.
- Should not be used for volume expansion or routine correction of mildly abnormal coagulation tests in patients who are not bleeding.
- Should not be used for warfarin reversal when prothrombin complex concentrate is available.|
- The precipitate formed when fresh frozen plasma is slowly thawed; it is not formed from the supernatant.
- A concentrated source of fibrinogen, factor VIII, factor XIII, von Willebrand factor and fibronectin.
- Principally used for fibrinogen replacement rather than factor VIII replacement.
- Consider in clinically significant bleeding with a fibrinogen level below 1.5 g/L.
- Consider prophylactically before an invasive procedure if the fibrinogen level is below 1.0 g/L.
- The standard adult dose is two pools of five units, followed by reassessment of the fibrinogen level.|
Compatibility testing
Component_Compatibility requirements| Red cells_Crossmatching is required. ABO-compatible red cells must be selected and units must lack any antigen corresponding to a clinically significant recipient antibody.| Platelets_Not routinely crossmatched. ABO-identical platelets are preferred but ABO-non-identical platelets may be used when necessary. RhD-compatible platelets are preferred for RhD-negative girls and women of childbearing potential; anti-D immunoglobulin should be considered if RhD-positive platelets are given.| Fresh frozen plasma_Not crossmatched, but ABO-compatible plasma should be selected. RhD matching and anti-D prophylaxis are not required.| Cryoprecipitate_Not crossmatched. ABO-compatible cryoprecipitate is preferred, although suitably selected ABO-non-identical cryoprecipitate may be used in adults when necessary. RhD matching is not required.|CMV-seronegative blood components
All UK red-cell and platelet components are routinely leucodepleted. CMV-seronegative red cells and platelets are reserved for:- intrauterine transfusions
- neonates up to 28 days after the expected date of delivery
- elective transfusions during pregnancy, but not during labour or delivery
- CMV-seronegative patients receiving granulocyte transfusions, as granulocytes cannot be leucodepleted
CMV-seronegative components are not routinely required for haematopoietic stem-cell or solid-organ transplant recipients. Leucodepleted red cells and platelets are considered sufficient, alongside appropriate CMV monitoring. In an emergency during pregnancy, leucodepleted components should not be delayed while CMV-seronegative components are sourced.
Cell salvage
Cell salvage is a form of autologous transfusion in which blood lost during or after surgery is collected and returned to the same patient.
Intraoperative cell-salvage devices:- collect shed blood into an anticoagulated reservoir
- separate and wash the red cells
- resuspend the red cells in sodium chloride 0.9% before reinfusion
- remove most plasma, platelets, coagulation factors and contaminants
Unwashed, filtered postoperative salvage systems may also be used in selected settings.
Cell salvage should be considered when blood loss is expected to exceed 500 mL or when it is likely to reduce exposure to donor red cells. It may be acceptable to Jehovah's Witnesses, but individual wishes must be discussed and documented before surgery.
Malignancy and infection are not absolute contraindications. The risks and benefits should be assessed individually, specific consent obtained and a leucocyte-depletion filter considered when salvaged blood is reinfused.
Warfarin reversal for emergency surgery or major bleeding
1. Stop warfarin and check the INR.
2. If surgery can be delayed for 6–8 hours:- give intravenous vitamin K, typically 5 mg
- recheck the INR before surgery
- give four-factor prothrombin complex concentrate (PCC), for example Beriplex or Octaplex
- give intravenous vitamin K at the same time to sustain reversal
- PCC contains factors II, VII, IX and X and produces rapid reversal
- the PCC dose depends on the presenting INR, body weight and local protocol; doses are generally 25–50 units/kg
- recheck the INR after administration
Fresh frozen plasma is not recommended for routine warfarin reversal because PCC acts more rapidly, achieves more reliable correction and avoids the large transfusion volume required with plasma.