At what temperature is blood stored in blood banks?

 # At what temperature is blood stored?

 A. -4 degrees

B. 4 degrees

C. 6 degrees

D. 8 degrees

The correct answer is B. 4 degrees celsius.

With the modern surgical and medical procedures, the demand for blood has greatly increased. It is for this reason that blood banks were started where blood from voluntary donors could be stored, so that it was always available on demand. Most blood banks have lists of would-be donors so that they may be contacted when required.

Storage of blood: After a donor has been screened for donation, one unit of blood (450 ml) is collected, under aseptic conditions, from the antecubital vein directly into a special plastic bag containing 63 ml of CPD-A (citrate-phosphate-dextrose-adenine) mixture. The blood bag is suitably sealed, labeled, and stored at 4 degree C, where it can be kept for about 20 days. (Faulty storage, i.e. overheating or freezing can lead to gross infection and hemolysis). The citrate prevents clotting of blood, sodium diphosphate acts as a buffer to control decrease in pH, dextrose supports ATP generation via glycolytic pathway and also provides energy for Na+- K+ pump that maintains the size and shape of red cells and increases their survival time, and adenine provides substrate for the synthesis of ATP, thus improving post-donation viability of red cells.

Blood is stored at low temperatures for 2 reasons: one, it decreases bacterial growth, and two, it decreases the rate of glycolysis and thus prevents a quick fall in pH.

Reference: A TEXTBOOK OF PRACTICAL PHYSIOLOGY Eighth Edition CL Ghai