This document discusses blood preservatives and the processes involved in preserving blood and its components. It addresses the biochemical changes that occur in stored blood, such as decreasing pH and ATP levels. Preservative solutions aim to minimize these changes by buffering pH and providing nutrients. Common preservatives mentioned are ACD, CPD, and CPDA, which contain ingredients like citrate, dextrose, and adenine. Newer additive solutions provide nutrients to packed red blood cells to extend their shelf life. Methods to rejuvenate stored blood and freezing techniques are also summarized. The document provides an overview of preserving different blood components like platelets, plasma and cryoprecipitate.

1. Dr.
ZIKRULLAH
BLOOD PRESERVATIVES

2. DEFINITION
 The process by which blood or its components
are kept viable outside the body (i.e., kept away
from decay by means of a chemical agent,
cooling, or a fluid substitute that mimics the
natural state within the body) is called blood
preservation.
 Goal of blood preservation is to provide viable
& functional blood components for patients
requiring blood transfusion.

3. Need of preservation of stored blood..?
 There is loss of red cell viability due to following
biochemical changes –
build up of lactic acid
decrease in pH
decrease in ATP level
decrease in 2,3 – DPG level
clotting of blood

4. DECREASE IN pH
 When blood is stored at 2-6 °C, glycolysis is
reduced but does not stop. Glycolysis results in
the production of lactate, with subsequent
decrease in pH,which alters red cells viability.
 Preservative solutions provide buffering
capability to minimize pH changes and optimize
the storage period.

5. DECREASE IN 2,3 – DPG
LEVEL
A fall in pH in the stored blood results in –
 decrease in red cell 2,3-DPG level, which results
in increase in hemoglobin-oxygen affinity.
 DPG-depleted red cells have impaired capacity to
deliver oxygen to the tissues.

6.  2,3-DPG levels in transfused blood are important
in certain clinical conditions –
 Myocardial functions improve following
transfusion of blood with high 2,3-DPG levels
during cardiovascular surgery.
 In patients with shock the transfusion of DPG-
depleted red cells makes a significant difference
in recovery.

7.  After transfusion, the red cells continue to
synthesize 2,3-DPG and levels return to expected
normal values within 24 hours.
 The acid-base status of the recipient,
phosphorous metabolism and degree of
metabolism influence the rate of restoration of
2,3-DPG.

8. DECREASE IN ATP
LEVEL
Decrease in ATP results in –
 leak of Na+ and K+ through red cell membrane
 increase in cellular rigidity and deformability
 decrease in red cell membrane integrity

9. Blood banking was born of wars
(HISTORY)
 The first anticoagulant preservative was introduced
by Rous and Turner in 1916,consisted of a citrate-
glucose solution. Rous Turner's solution as used for
storage of human blood during the First World War.
 During the Second World War acidified citrate
dextrose (ACD) solution was introduced .

11.  In 1957 Gibson developed an improved preservative
of citrate-phosphate-dextrose (CPD), which was less
acidic and maintained 2,3-DPG level better than in
ACD solution.
 In 1978 citrate-phosphate-dextrose with adenine
(CPDA-1) preservative was developed. The addition
of adenine improved the synthesis of adenosine
triphosphate (ATP) in the stored blood, which
prolonged the storage of blood/red cells at 2-4 °C to
35 days

12. So ,the important preservative solutions used are
–
 ACD ( acid, citrate, dextrose )
 CPD ( citrate, phosphate, dextrose )
 CPDA (CPD + adenine )

13. Action of ingredients of preservatives
Citrate - Calcium chelator , prevents coagulation,
retards glycolysis
 citrate toxicity- hypocalcaemia and
hypomagnesaemia ,This can result in myocardial
depression or coagulopathy.
 Management: Slowing or temporarily stopping the
transfusion allows citrate to be metabolised.
Replacement therapy may be required for
symptomatic hypocalcaemia or
hypomagnesaemia.

14.  Adenine-substrate for ATP syntesis, extends the shelf
life of red cells to 42 days as RBC has ATP dependant
cytoskeleton.
 Sodium di phosphate - prevents fall in ph.Buffer.
 Dextrose - improves red cell viability provides energy
for ATP synthesis decreases rate of hydrolysis of
phosphorus.
 Citric acid- prevents glucose caramalization during
autoclaving,

15. A. Acid citrate dextrose (ACD):
Composition –
 Trisodium citrate
 Citric acid (monohydrate)
 Dextrose (monohydrate)
 Distilled water
For each 100 ml of blood, 15 ml of the ACD solution
is needed

16. ADVANTAGES OF ACD-
 Preserves ATP level
 prevents haemolysis
 maintains pH
 Shelf life of whole blood / red cells in ACD = 21
days
 (> 70% transfused cells viable after 24 hours)
However level of 2,3 DPG lost early within first
week

17. B. Citrate phosphate dextrose (CPD) :
CPD is a modified ACD solution that is slightly
less acidic and therefore improves the
preservation of 2,3-BPG.
Composition- Trisodium citrate
Citric acid
Dextrose
Sodium phosphate
Distilled water
For each 100 ml of blood 14 ml of CPD is added.

18. CPD Solution –
 Better maintenance of 2,3 DPG
 decreases acidosis
 improves ATP synthesis
 Shelf-life of whole blood in CPD = 21 days

19. C. Citrate Phosphate Dextrose Adenine (CPDA):
Adenine - helps maintain high ATP levels
ATP is associated with red cell viability .Loss of ATP
causes increase in cellular rigidity & decrease in red cell
membrane integrity & deformability. A decrease in ATP
allows the leak of Na & K through red cell membrane.
- shelf-life = 35 days

20. Current trends in blood preservation
research
Traditional preservatives were put into use when
whole blood was the major product. With the
advent of component therapy, use of red cells
increased , and so the need of different
preservative methods.
 1.Additive solutions
 2.Rejuvenation solutions
 3.Red cell freezing

21. Optimal Additive Solution (OAS)
for Preservation of Red Cells
 Normally 40% of adenine and glucose present in
the whole blood, was removed in preparation of
packed RBC and thus there was decrease in its
viability particularly in last 2 weeks of storage.
 However preparation of concentrates of haematocrit
less than 80% by allowing adequate plasma to
remain, lead to lower plasma yields affecting FFP
and Cryoprecipitate production.

22.  Thus use off additive solutions for preparation of
packed RBC allowed recovery of maximum
amount of plasma for preparation of FFP and
cryoprecipitate.

23.  Different types of additive systems are now in use
-
(1) Adsol ( AS-1 )
(2) Nutricel (AS-3)
(3) Optisol (AS-5)
 OAS added to the red cells after separating them
from plasma.

24. AS-1 AS-3 AS-5
Sodium citrate - 588 mg -
Monobasic sodium phosphate - 276 mg -
Citric acid - 42 mg -
Dextrose 2.20 g l.l0 g 900 mg
Adenine 27 mg 30 mg 30 mg
Mannitol 750 mg 525 mg
Sodium chloride 900 mg 410 mg 877 mg
Vol 100 ml 100 ml 100 ml
Primary bag anticoagulant CPD CPD2 CPD
COMPOSITION OF ADDITIVE SOLUTIONS

25. The advantages of using optimal additive
solution (OAS) to red cells are :
 1. Provide the red cells with adequate nutrients.
 2. Better storage condition for red cell preparation
and lowering of viscosity for ease of transfusion.
 3. Increased yield of plasma for plasma
fractionation.
 4. Removal of unwanted buffy coat
 5. Avoid unnecessary transfusion of plasma

26.  6. Additive system increase the level of ATP and
red cells, extending the shelf-life of the red cells
to 42 days.
 7. More than 80% red cells survive in circulation
24 hours after transfusion of blood stored for 42
days.

27. DISADVANTAGE OF ADDITIVE SOLUTIONS:
Additive solutions do not maintain 2,3DPG
throughout the storage time .Therefore , blood
stored in additive solutions is not given routinely
to newborn infants.

28. REJUVENATE SOLUTIONS
 PURPOSE : To increase levels of 2,3 DPG and ATP in
stored red cells Added at any time between 3 days post
collection and three days after expiration of red cells.
 Consists of – phosphate
inosine
glucose
pyruvate
adenine
Rejuvenation process is expensive and time consuming and is
rarely used.
(in autologous donations/rare blood groups)

29. RED CELLS – FROZEN STATE
 Frozen red cells can be stored for 10 yrs but
freezing damages red cells due to the intracellular
ice formation & hypertonicity . To counter this
glycerol is added.
 Glycerol prevent freezing injury in human red
cells & red cells mixed with glycerol could be
frozen without damage.

30. PLATELET PRESERVATION
 Preservation of viable & functional platelets
depends on –
 Temperature – should be stored at 22 – 24 C
with continuous gentle agitation in platelet
incubator & agitator.
 pH – should be above 6.
 Plastic bag – maintenance of pH & function of
platelets depends on permeability of storage bag
to oxygen & CO2.

31.  Platelets should be prepared within eight hours of
phlebotomy and stored at 20-24 C with
continuous agitation, to prevent aggregation
which can result in loss of viability.
 Platelets are stored in large flat bags with a high
surface-to-volume ratio ,on agitators to facilitate
oxygen diffusion. If there is no agitation for more
than 24 hours, the bag contents become hypoxic
and the metabolism shifts to anaerobic glycolysis
so that the contents become acidotic and the
platelets lose their function.

32. FRESH FROZEN PLASMA
 Shelf life of FFP is 12 months at – 18 C or lower.
 After thaw FFP can be stored at 2 – 6 C for 12 hrs
before transfusion.
 If FFP can not be used within 1 yr or thawed
plasma is not used within 12 hrs it is re
designated as single donor plasma which can be
stored further for 4 yrs at – 18 C or lower.

33. CRYOPRECIPITATE
 Cryoprecipitate is prepared from plasma. It
contains fibrinogen ,von Willebrand factor and
factor VIII.
 Cryoprecipitate can be stored for 12 months at –
18 C or lower.
 Thawed cryoprecipate can be stored for 6 hrs at 2
– 6 C & pooled cryoprecipitate kept at 2 – 6 C
should be used within 4 hrs.

34.  REFERENCES :
 REFERENCES Rossi’s Principle of Transfusion
Medicine (4th Edition) Modern Blood Banking &
Transfusion Practices by Denise M. Harmening (
4th Edition) AABB technical manual – 17 th
edition Storage of Blood- B.A.L Hurn,1968
Clinical practice of Transfusion Medicine- Petz

35. THANK YOU