Stored blood as compared to fresh blood has:
|A||More 2,3 DPG|
|B||High extracellular K+|
|C||High extracellular Hb|
1. In bank blood that is stored, the 2,3-DPG level falls Q and the ability of this blood to release O2 to the tissue is reducedQ.
2. Cellular metabolism, membrane ion pump failure and Hemolysis during blood storage →leads to → Hyper kalemia and Acidaemia with rapid blood transfusion
3. At 4°C (in stored blood), the survival of platelets is considerably reduced and few are functionally usefull after 24 hours Q
4. Clotting factors VIII and V are liable and their level fall quickly in stored blood Q
5. Each unit contain - 450 ml of blood and 60ml CPD solution (citrate - phosphate - dextrose) Q
6. One unit of whole blood will raise the Hb% by Igm/dL Q
7. CPD blood has shelf-life of 3 weeks while - CPD-A (Adenosine) has 1 -5 weeks. Q
8. Blood transfusion in anaesthetized pts especially in children, are vulnerable to hypothermia
9. Blood filters remove micro-aggregates of more than 20μm diameter during transfusion. The ordinary infusion set-filter pore size is about 170μm,
10. Definition of the massive blood transfusion:
→ 5 units blood in 1 hours in 70kg adult.
→or, total blood volume replacement by stored blood in under 24 hours.
11. Acid-citrate dextrose (ACD) blood stored for 21 days while CPD blood can be usefully stored for 35 days Q