Blood Component Therapy: What a clinician needs to know !

Blood Component Therapy

•Gravity•Apheresis

Blood Components:

•Red Cell Concentrate ( pRBC)•Leukoreduced RBC•Platelet Concentrate•Leukoreduced Platelets•Fresh Frozen Plasma•Cryoprecipitate•Cryo poor Plasma•Granulocyte concentrate

•Low and high speed Centrifugation

Whole Blood

Soft spin @ 2000 rpm for 3min

pRBC Platelet Rich Plasma (PRP)

Hard Spin @5000 rpm for 5 mins

Platelet ConcentrateFresh Frozen Plasma

CryoprecipitatePlasma Derivatives

Need of blood component therapy:It aims at transfusing only the required component.It helps to prevent the wastage of a resource , ie, blood.Blood from a single donor can be used to provide blood

components to multiple patients.Prevents circulatory overload.

Blood CollectionIs done using a 16 G needle450 ml of blood is collected in a

continuous flow into a primary bag which has 63 ml of anticoagulant and preservative solution.

The primary blood collecting bag is attached to 1, 2 or 3 satellite bags forming the basis of component separation through a closed system.

Blood preservatives:

Solution

Purpose Storage Period

Components

CPD Anticoagulation and storage of blood

21 days

Sodium Citrate : Binds with Calcium and acts as an anticoagulantPhosphate (Sodium di phospahte): Prevents fall in pHDextrose: Supports ATP generation by glycolytic pathway.*Adenine: Substrate for ATP synthesis.

CPDA 1 Anticoagulation and storage of blood

35 days

SAG- M Red cell preservation

42 days

Sodium chloride: Adjusts osmotic pressure Adenine: Substrate for ATP synthesisGlucose: Supports ATP productionMannitol: Supports integrity of red cell membrane

Whole BloodThe only indication for whole blood transfusion today is

Exchange transfusion.Stored at a temperature of 1-6. CRaises Hb by 1 gm% and Hematocrit by 3%.Should be transfused within 4 hours of issuing from blood

bank.

pRBCHas the same Oxygen carrying capacity as Whole blood but

has half the volume ( prevents circulatory overload).Has significantly lower levels of electrolytes, metabolites and

agglutinins.Volume: 200 mlStored at a temperature of 1-6. CRaises Hb by 1 gm% and Hematocrit by 3%Should be transfused within 4 hours of issuing from blood

bank.

Leukoreduced RBCThese are packed red cells from which 99.9% white cells have

been removed either by filtration or by freezing/thawing/washing.

The white blood cells are the reason for non hemolytic febrile reactions.

The immunomodulatory effect of blood transfusion is due to WBC’s which is said to increase the risk of Post operative infections.

Leukoreduction is an expensive procedure.Leukoreduction reduces the risk if transmission of EBV, CMV

and HTLV.

AAAB Clinical practice guidelines for Red Cell transfusion (2016)It recommends a restrictive RBC transfusion threshold of

7gm% in hospitalised hemodynamically stable patients, including critical care patients, rather than 10 gm%.

For patients undergoing orthopedic and cardiac surgery and those with existing Cardiovascular disease, it recommends restrictive RBC transfusion threshold of 8 gm%.

AAAB: American Association of Blood Banks

Platelet concentrate:It is harvested from PRP ( platelet rich plasma) by separating

the plasma.Volume: 50-80 mlDose: 1 unit/ 10 kg body weight1 unit increases the platelet count by 10-15, 000/ul.Stored at 20-24. C on an agitatorShelf life: 5 daysSDP ( Single donor platelet) is equivalent to 6 RDP units.1 unit SDP has 3*10 11 platelets.

Indications for Platelet Transfusion:In stable patients with normal platelet function, when platelet

count is <10,000.For elective procedure: Minor (eg, LP) when count <50000 Major suregry when count <100000

Fresh Frozen PlasmaIt has: all coagulation factors Plasma proteins ( eg, albumin) Factor VIII FibrinogenVolume: 180-220 mlStored at -20.CShelf life: 1 yearDose: 15-20 ml/kg body weightTransfusion should be completed within 30 mins of issue.

Indications for FFP use:Deficiency of coagulation factors ( Vit K dependent)Hemophilia ADICMassive transfusionReversal of warfarin therapy

It should not be used for:Volume expansionImmunoglobulin replacementNutritional SupportWound Healing

CryoprecipitateThey are cold precipitated proteins of plasmaVolume: 10-20 mlVery rich in Factor VIII , Fibrinogen and vWF ( von

Willebrand’s factor).Stored at -20.CShelf life: 1 yearDose : 1 unit /10 kg body weightMainly used for treating coagulopathy due to

Hypofibrinogemia.