Faculty of Allied Medical Science. Blood Banking (MLBB 201). Changes that occur in Stored Blood. Prof. Dr. Nadia Aly Sadek Prof. in Haematology and Director of Blood Bank Centre, Medical Research Inst, University of Alexandria. Outcomes.
Blood Banking (MLBB 201)
Prof. Dr. Nadia AlySadek
Prof. in Haematology and
Director of Blood Bank Centre,
Medical Research Inst, University of Alexandria
Loss of organic phosphates
Release of pro-inflammatory cytokines
Some changes take place slowly and some take place rapidly.
1- Increased in-hospital mortality
2- Increased rates of sepsis
2- Delayed healing of wounds
3- Tumour recurrence.
Immediately after blood donation, the red cells are subjected to an acidic, hypotonic, anticoagulant solution which damages a small proportion of them irreversibly.
Cells that survive the first 24 hours will remain viable for the end of their life span.
At least 70% of them remain viable in the recipient’s circulation 24 hours after transfusion.
Platelet function declines to zero after 24 hours of storage.
1- Oxygen affinity
Stored blood has depleted levels of 2,3 Diphosphoglycerate (DPG) which causes the oxygen dissociation curve to shift to the left, so increasing the oxygen affinity of hemoglobin = less release of oxygen to the tissues.
There is a time-dependent reduction in intracellular RBC ATP which is essential for:
- membrane stability
- glucose transport
- oxidative stress defense mechanisms
- membrane phospholipid distribution
The biochemical changes that occur in the stored bags lead to alteration in corpuscle shape, decreased deformability, increased aggregability and intracellular viscosity as well as changes in osmotic fragility.
RBcs transfusion produces a state of immunosuppression in the recipients which predisposes them to acquire infections or develop transfusion-related acute lung injury.
But it may become a problem with rapid transfusion of large amounts of stored blood especially in severe renal failure or in neonatal exchange transfusion.
Labile coagulation factors i.e. FV and FVIII have a 50% decrease in activity within the first 72 hours of storage, but the other coagulation factors remain normal.
1- Pre-storage filtration
2- Bedside filtration.
Each unit of whole blood is filtered before storage. Pre-storage filtration has many advantages:-
1- Diminished accumulation of leucocyte-derived cytokines during storage.
2- Removal of cells infected with cytomegalovirus (CMV) and Epstein-Bar virus (EBV) and HTLV-1 virus.
4- Improves RBCs potency
5- Reduces HLA alloimmunization
It may activate the complement system.
It is carried at the beside of the patient with a different type of filter.
Although it removes the remaining leucocytes yet it does not remove the cytokines already secreted from the leucocytes and which are responsible for the transfusion reactions.
a- Bedside filtration is better than prestorage filtration
b- Tetany is a sign of hypocalcemia
c- Potassium decreases in blood bags by prolonged storage
d- RC membrane rigidity decreases by storage.
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