General Surgery
Blood Transfusion
MBBS surgery notes on blood transfusion: blood groups, components, massive transfusion and transfusion reactions, mapped to NMC codes SU3.1 to SU3.3.
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Blood Transfusion
MBBS surgery notes on blood transfusion: blood groups, components, massive transfusion and transfusion reactions, mapped to NMC codes SU3.1 to SU3.3.
This chapter covers safe blood transfusion in surgery, from blood grouping and component therapy to the recognition and management of transfusion reactions. It includes the principles of massive transfusion and modern balanced resuscitation ratios.
High-yield: Blood Transfusion
- ABO and Rh D compatibility are the first check before transfusion; ABO incompatibility causes the most dangerous acute haemolytic reactions.
- Group O red cells are the universal donor for red cells, while group AB plasma is the universal donor for plasma.
- Packed red cells are stored at 2 to 6 degrees Celsius for up to 35 to 42 days depending on the anticoagulant preservative used.
- Platelets are stored at 20 to 24 degrees Celsius with agitation and last about five days, so they are always in short supply.
- Fresh frozen plasma replaces clotting factors and is used for coagulopathy, not as a volume expander.
- Cryoprecipitate is rich in fibrinogen, factor VIII, von Willebrand factor and factor XIII, and is given for hypofibrinogenaemia.
- The commonest transfusion reaction overall is a febrile non-haemolytic reaction from donor leucocytes and cytokines.
- Acute haemolytic reaction from ABO mismatch presents with fever, loin pain, hypotension and haemoglobinuria and needs the transfusion stopped at once.
- Transfusion-associated circulatory overload and transfusion-related acute lung injury are the leading causes of transfusion-related death.
- Massive transfusion is roughly one blood volume in 24 hours, or 4 or more units in one hour, and risks hypothermia, hypocalcaemia and coagulopathy.
- Citrate in stored blood binds calcium, so massive transfusion can cause hypocalcaemia needing calcium replacement.
- Modern trauma resuscitation favours a balanced 1:1:1 ratio of red cells, plasma and platelets.
- Autologous transfusion and intraoperative cell salvage reduce the need for donor blood in elective and trauma surgery.
- Delayed haemolytic reactions occur days later from an anamnestic antibody response and present with a falling haemoglobin and jaundice.
- Restrictive transfusion, aiming for a haemoglobin trigger near 7 g/dL in the stable patient, is as safe as a liberal strategy and uses less blood.
Blood components and their main uses
- **Packed red cells:** Restore oxygen carrying capacity; stored at 2 to 6 degrees for up to 35 to 42 days.
- **Platelets:** For thrombocytopenia or platelet dysfunction; stored at room temperature with agitation for about 5 days.
- **Fresh frozen plasma:** Replaces all clotting factors for coagulopathy; not a volume expander.
- **Cryoprecipitate:** Concentrated fibrinogen, factor VIII, von Willebrand factor and factor XIII for hypofibrinogenaemia.
NMC competencies in this chapter
- **SU3.1:** Blood groups, cross-matching and blood components
- **SU3.2:** Indications and use of blood and component transfusion
- **SU3.3:** Complications and hazards of blood transfusion
Frequently Asked Questions
Why is ABO matching so important?
ABO incompatibility triggers an acute intravascular haemolytic reaction with fever, loin pain, hypotension and haemoglobinuria, which is the most dangerous transfusion complication and can be fatal.
What is the commonest transfusion reaction?
A febrile non-haemolytic reaction caused by donor leucocytes and cytokines. It is unpleasant but usually benign and is reduced by using leucodepleted blood.
What defines a massive transfusion?
Roughly one whole blood volume replaced within 24 hours, or four or more units within an hour. It risks hypothermia, hypocalcaemia from citrate and dilutional coagulopathy.
What haemoglobin level should trigger transfusion?
In stable patients a restrictive trigger near 7 g/dL is as safe as a liberal approach and reduces donor blood use; the trigger is raised in active bleeding or cardiac disease.
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