Blood Transfusion Flashcards
The Scottish National Blood Transfusion service aim to make the blood donated as safe as possible for patients. How do they do this?
There is strict medical selection of donors, which is intended to exclude anyone whose blood might harm the recipient (e.g. by transmitting infection). Many factors can exclude them from donating e.g. foreign travel, recent tattoos etc.
As an additional precaution to minimise any risks that patients may be exposed to CJD through transfusion, the UK Blood Services will not accept blood donations from people who believe they have had a transfusion since 1980.
In addition to this we have many current and future issues which may further decrease our donor population e.g. an aging population and testing for CJD. Flu pandemics eg Swine flu can also affect the number of people who are able to attend session to donate blood.
what are blood donations tested for?
evidence of hepatitis B, hepatitis C, HIV-1, HIV-2, HTLVI and syphilis.
Each donation is also tested to determine the ABO and RhD blood group.
how do you store red cells?
Red cells must be stored in an authorised blood fridge at a temperature of 2-6oC with an audible alarm system and functional temperature recorder and never in a domestic/drug fridge.
what should you do to red cells left out of fridge for more than 30mins without beginning transfusion?
If red cells are left out of fridge >30mins and not being transfused they must be clearly marked and returned to Transfusion Laboratory or Blood Fridge as per hospital policy.
what is the max amount of time for red blood cell transfusion?
within 4 hours of removal from fridge
what are indications for red blood cell transfusion?
- To save the life of a patient who loses a large volume of blood
- To enable patients to have surgery that involves the loss of a large volume of blood
- To enable patients to receive treatment for leukaemia or cancer
- To maintain or improve the lives of patients with some chronic conditions
how should platelets be stored
Platelets are stored in the Hospital Transfusion Laboratory (HTL) at a temperature of +22oC on an agitation rack. They should never be stored in a blood fridge, as this causes platelets to clump together making them useless.
Platelets can be stored for short periods up to 2 hours in the clinical area un-agitated provided they are not in direct sunlight or near radiators.
how long can you/should you transfuse platelets
Platelets must be infused within 4 hours of spiking the pack. Platelets are usually infused over 30-60 mins but this will depend on the patient’s clinical condition.
what are indications for platelet transfusion
- Platelets play a primary role in haemostasis i.e. prevention of bleeding
- Bone marrow failure
- Platelet function disorders
- Massive transfusion
- Cardiopulmonary bypass
how do you store plasma
FFP/Cryoprecipitate are stored frozen at -25oC or below for up to 2 years
When required for use they are thawed rapidly at 37oC. Once thawed the clotting factors in FFP/Cryoprecipitate start to deteriorate and they cannot be refrozen.
how soon after thawing should you use platelets
within 4 hours
what are indications for platelets
- Patients who are bleeding
* Replacement of clotting factor deficiency
what happens if you give the wrong type (ABO) of blood to a patient
If red cells carrying A or B antigens are transfused to someone who has antibodies to these then a severe immune reaction can occur which may be fatal. The red cells are not compatible with the recipient.
The transfusion of only a few mLs of the wrong (incompatible) ABO group can trigger a massive immune response leading to shock and disseminated intravascular coagulation. Individuals may die from circulatory collapse, severe bleeding or renal failure, often within minutes or hours.
what type (ABO) can be given to anyone in an emergency and why
Group O blood can be safely given to all groups of patients in a life threatening situation as there are no A or B antigens to react with the recipient’s antibodies.
why should RhD negative females of child bearing potential never be transfused with RhD positive blood?
Following exposure to RhD positive blood an RhD negative woman can make immune anti-D which can cause haemolytic disease of the newborn or severe fetal anaemia and heart-failure (hydrops fetalis).
