The ‘Blood cold Chain’ is the system for storing & transporting blood & blood components so that they are kept at the correct temperature at all times from collection from donor to administration to the patient. Any break in the blood cold chain increase the dangers for the recipients of blood  products.
 
The ‘Blood cold Chain’ is the systematic process for safe storage & transportation of  blood & blood components so that they are kept at the correct temperature at all times from blood collection from a donor to administration of blood to a patient  in need of transfusion. 
 
Blood bank refrigerators ,Plasma freezers, platelet agitator cum incubators, blood transport boxes are the blood cold equipments used for storage of blood and components
 
WHOLE BLOOD AND RED CELLS
Red cells & whole blood must always be stored at a temperature between +2 degree C to +6 degree C in a blood bank refrigerator. Blood bank refrigerators have in built temperature monitoring and alarm devices and a cooling fan to ensure even distribution of cold air through out the equipment .Maintenance of above storage temp is essential to maintain the oxygen carrying ability of blood.  The upper limit of 6 degree C is essential to minimize the growth of any bacterial contamination in the  unit of blood.
 
Below 2 degree C  red cells  become haemolysed.  So they must never be allowed to freeze. Haemolysed cells if transfused can cause renal failure & fatal bleeding problems.
 
Depending on the type of blood bag used the shelf life ranges from 35- 42 days. Whole blood & red cells should be issued from the blood bank in the blood transport box or insulator carrier that will keep the temperature under 10 degree C, if the room temperature is greater than 25 degree C or if there is a possibility that blood will not be transfused within 30 minutes.
 
Once issued red blood cells should be transfused within ½ hour of release from BTS.  If not required should be sent back to Blood center immediately.
   
FRESH FROZEN PLASMA(FFP)
Fresh Frozen Plasma  ( plasma separated from a unit of blood within 6-8 hrs of donation and rapidly frozen) is stored in Blood Transfusion centre at -40 degree C or colder .It has a shelf life of one year.  If not stored at this temp the coagulation factors as Factor VIII and Factor V deteriorate and the amount is greatly reduced thereby defeating the purpose for which it is to be administered.
 
FFP  needs to be  thawed before transfusion. in the blood centre in a plasma thawing bath. at 30 degree C - 37degree C which  takes about 30-45 minutes   FFP should be transported in a blood transport box in which the temperature is maintained   between +2 degree C to 6 degree C. Once thawed FFP should be infused within 30 minutes.
 
If not required for immediate use it can be kept at 2 degree C – 6 degree C & transfused within 24 hours.  Once thawed the FFP can not be refrozen & has to be discarded .therefore FFP should be demanded only when essential & in the required quantities.
 
CRYOPRECIPITATE
Cryoprecipitate is the cold insoluble portion of plasma remaining after FFP has been thawed and contains Factor VIII ,Von Willebrand factor, factor XIII and fibrinogen. For preparation of cryoprecipitate  plasma is separated from a unit of blood within 6-8 hrs of donation and rapidly frozen within30 minutes, plasma is then thawed slowly at below+ 4 degree C  to obtain maximum yield of cryoprecipitate It is finally is stored in Blood Transfusion centre at -40 degree C or colder . it has a shelf life of one year..  The volume of cryoprecipitate  is 25-30 ml. cryoprecipitate needs to be s thawed at 30 degree to 37 degree C  in a water  bath for about 15-30 minutes.  Once thawed cryoprecipitate should be transfused within 30 minutes.  If not immediately transfused cryoprecipitate  is kept at 2 degree C- 4 degree C & can be transfused within 4 hours of thawing. It can  not be refrozen, if not transfused and  has to be discarded.
 
PLATELETS – PLATELET RICH PLASMA (PRP)/PLATELET CONCENTRATE (PC)
APHERESED, SINGLE  DONOR PLATELETS (SDP)
Platelet are prepared by manual as well as automated methods and then stored at 22 degree C -24 degree C in platelet agitator cum incubator to maintain platelet  function of preventing spontaneous bleeding or stop bleeding in those patients with established thrombocytopenia or hypo plastic anemia or bone marrow failure. Whole blood for  separation of platelets  should be kept at 20-24 degree C  before processing as lower temperatures affect platelet function and its separation.. Platelets should be prepared within 8 hrs of phlebotomy and stored at 20-24 degree C with continuous agitation.to prevent aggregation which can result in loss of viability. Platelets have  a shelf life of 3-5 days depending on the type of blood bag used. Since they are stored at room temp there is a risk of bacterial contamination therefore the temperature in the platelet storage area should be maintained at ambient temperature below +24 degree C Platelets should be  transported  in a blood transport box that keeps the temperature in the correct range of about 20 degree C – 24 degree C. Platelets should never be REFRIGERATED and should be transfused  as soon as possible. 
 
INSPECTION OF  BLOOD BAGS PRIOR TO ISSUE/ADMINISTRATION        
Blood bags should be inspected for deterioration/damage during storage before blood is  issued from the blood centre and before transfusion at the bed side. Any discoloration or signs of leakage is a warning sign of bacterial contamination that can cause fatal reaction if transfused therefore it is important to check each bag for signs as shown in the figure below


 
BLOOD TRANSPORT BOXES
Blood transport Boxes should be used for whenever blood is moved from the blood centre to patient bed side or operation theatre. It is important to use clean and sturdy transport boxes  that maintain optimum temperature required for blood during  transport. 
 
STORAGE Of BLOOD PRODUCT PRIOR TO TRANSFUSION
 

 
N.B.-All unused products should be returned to blood bank.           
 
WARMING BLOOD
 
On an average it takes about 30 minutes for blood to reach +10 degree C from 2-6 degree C. Cold blood administered at a slow rate does not have any ill effect on the patient so blood does not require any warming as such prior to transfusion.
 
Warming of blood is only required in large volume rapid transfusions in Adults where flow rate is greater than 50 ml/kg/hour  and in Children where flow rate is  greater than 15 ml/kg/hour
 
Blood Warming is also  required in Exchange transfusion in infants and in patients with clinically significant cold agglutinins. Blood should be warmed in special warmers designed for the purpose in the clinical areas