Blood product preservation

lecture 2

What are some aspects of RBCs that must be considered in order to preserve blood?

RBCs must be:

1. flexible

2. deformable

3. permeable

What is the chemical composition of an RBC (that is with carbohydrates, proteins, and lipids)?

52% protein, 40% lipid, 8% carb

What are the two kinds of proteins found in an RBC?

integral and peripheral

Provide some examples of peripheral proteins.

actin, ankyrin, spectrin, band 4.1

Provide some examples for integral proteins.

Glycophorin A, B, C

What kind of membrane does the RBC have?

semipermeable lipid bilayer

What are the approved red cell preservative solutions?

ACD-A, CPD, CP2D, CPDA-1

What is the storage time using ACD-1?

21 days

What is the storage time of CPD?

21 days

What is the storage time of CP2D?

21 days

What is the storage time of CPDA-1?

35 days

In general, what temperature should blood be stored at?

1-6 C

What kind of additive is used to freeze red cells?

glycerol, high conc like 40%

What temperature are red cells frozen at?

-65 C

As time goes on, what happens to a pack of red cells (pH, lactic acid, glucose consumption, ATP levels, CO2 levels, 2,3-DPG)?

pH: decreases

lactic acid: increases

glucose consumption: decreases

ATP levels: decreases

CO2 levels: increase

2,3-DPG: decreases

What kind of metabolic pathway is used to produce ATP in RBCs?

anaerobic glycolytic pathway

What are three other pathways that support RBC metabolism?

PPP, methemoglobin pathway, and Luebering-Rapoport shunt

Which pathway produces 2,3-DPG? What is it used for?

Luebering-Rapoport shunt, used for the affinity of hemoglobin to grab onto oxygen and release

What is the primary function of hemoglobin?

gas transport, or oxygen delivery to tissues

What is the secondary function of hemoglobin?

CO2 excretion

List two types of blood substitutes.

1. Hemoglobin based oxygen carriers

2. perfluorocarbons

What are some advantages of hemoglobin based oxygen carriers?

long shelf life, stable, no antigens, no blood typing needed

What are some disadvantages of hemoglobin based oxygen carriers?

short intravascular life, possible toxicity, increased oxygen affinity (wont let it go)

What are some advantages of perfluorocarbons?

inert, lack antigens, easily made

What are some disadvantages of perfluorocarbons?

adverse side effects, high oxygen affinity, retention issues

What are the functions of platelets?

Stop bleeding by making the temp platelet plug, stabilize fibrin formation, maintain vascular integrity

What happens to the metabolism of store platelets as time goes on (pH, lactate, ATP, morphology)?

pH: decreases

lactate: increases

ATP: decreases

morphology: from disk to spherical

What is the storage time and temperature of platelet concentrates?

time: 5 days

temp: 20-25 C, basically RT

What special requirement is needed for storing platelets at RT?

gentle continuous agitation

What is the FDA minimum platelet count for apheresis?

3 × 10¹¹ platelets

What is the FDA minimum platelet count for pooled platelets?

5.5 × 10¹⁰ platelets

What is the FDA requirement for pH of platelets?

pH > 6.2

What are nine factors that influence platelet storage?

1. temperature → 20-24 C

2. pH → 6.2-6.8

3. total platelet count

4. volume of plasma

5. agitation

6. hydrogen ion accumulation

7. anticoagulant used

8. method of concentrate preparation

9. storage container composition

Why should blood components be frozen?

• autologous transfers

• freeze to extend the shelf life

• rare blood types must be stored for rare cases

What is the biggest concern regarding platelet storage?

bacterial contamination

Which kinds of blood preserved products are good for newborns?

CPD, CP2D, CDPA-1

Which blood preserved products can be rejuvenated?

CPD, CDPA-1, AS-1