BLOOD AND BLOOD PRODUCTS

CONTENTS OF BLOOD:

Cells

Red Cells-Erythrocytes

White Cells - Leukocytes - Granulocytes, Monocytes, Lymphocytes

Platelets

Plasma Contains Water 91%

Plasma Proteins. Albumin 4.5g/100ml

Globulins 2.7g/100ml

Clotting factors- prothrombin & Fibrinogen

Electrolytes 0.9% Na, Cl, K, etc

Serum-Plasma - clotting factors

BLOOD FORMATION

Adults: 

Erythrocyte, leukocyte and platelet formation occurs mainly bone marrow of axial skeleton.

Foctus :

erythropoiesis also occurs in liver, kidney and spleen.

Granulocytes, monocytes and some lymphocytes also produced in the bone. Lymphocytes may also be produced in the lymphoid tissue such as thymusand spleen.

Red cell mass maintained within normal limits by hormone erythropoietin Erythropoietin is a glycoprotein, produced mainly in the kidney as a response to cellular hypoxia - explains the mechanism of anaemia in patients with renal failure Many factors are required for normal RBC formation

Iron 100ml of blood requires 50mg of iron for daily requirements men 5mg,women 10mg

Vitamin B12 absorbed in combination with Intrinsic factor (secreted by the stomach)

Folic Acid - important for RBC maturation.

WHOLE BLOOD AND PREPARATIONS OF RED CELLS

Administered as units ie. the quantity taken at one time from a donor, volume is altered by the processing.volume is altered by the processing WHOLE BLOOD

Volume 405-495 ml in container with anticoagulant 63-75 ml / Dextrose -life 28 days.

ACD Adenine/Citrate CPD-life 28 days.

CPDA Citrate / Phosphate / Dextrose /Adenine - life 35 days.

Whole blood contains all the cellular and plasma constituents of blood, subject to changes on storage, except in ionized calcium which is precipitated by the citric acid contained in the anticoagulants

FRESH BLOOD

Whole blood less than 24hrs old and still contains the clotting factors and

viable platelets, reserved for transfusion of neonates and occasionally following cardiac surgery.

WHOLE BLOOD

Used for patients requiring replacement of RBC and circulating volume ie bleeding. Stored whole blood may have poor haemostatic properties and fresh frozen plasma and platelets may have to be given.

RED CELL CONCENTRATES

Red cells obtained by removing 200-250ml of plasma by centrifuge Often labeled plasma reduced blood Plasma obtained used in the manufacture of various blood products Packed cells are used to restore red cell mass in anaemic patients who do not require an increase in circulating volume.

 In practice all blood is to some extent plasma reduced as small volumes are removed which is use in the production of Cryoprecipitate Platelets are also often removed.

RED CELLS SUSPENDED IN OPTIMAL ADDITIVE SOLUTIONS (O.A.S.)

Red cells suspended in a protein poor solution.

Obtained by centrifugation of a unit of blood, removal of platelets and addition of 100ml of O.A.S.- Sodium Chloride,Adnine and Manitol. The resulting cell suspension has low viscosity allowing fast administration  and has shelf life of 5 weeks.

Produces a large amount of plasma for blood products Contraindications: Not recommended for open heart surgery.

Not for neonates or infants.

Not for patients with anaemia & low platelets ie liver, renal disease and burns.

TRANSFUSION OF PLASMA COMPONENTS AND PRODUCTS 

Most demand for Human Albumin Solution, Plasma Protein Fraction,

Factor V111 & Platelets From every six units it is possible to obtain:

6 units red cell concentrate

6 platelet concentrates

6 cryoprecipitate (factor 8 for clotting)

2 vials Tactor IX concentrate

2 400ml bottles of PPF

8 for clating

7 vials of normal immunoglobulin

ALBUMIN PREPARATIONS

Protein solutions containing predominantly Albumin prepared by fractioning large pools of plasma.

Two types available - PPF & Human Albumin Solution Both have purity of 95% PPF 90% Albumin, also contains 160mmol sodium usually in 400mb bottles.

PPF is used to replace plasma proteins in patients who have impaired synthesis and for expansion of plasma volume . Human Albumin Solution 'salt poor albumin is a solution containing 29g A albumin, 130mmol sodium. It comes in 100ml bottles Used for severe low protein in acute nephrotic syndrome or with liver disease.

Albumin solutions are expensive and products are in short supply, should not be used to correct low protein from malnutrition.

For many patients synthetic expanders are more economical.

FRESH FROZEN PLASMA 

For clinical use it is separated from single units of blood and rapidly frozen

- within 6 hours of donation FFP is ABO &Rh group specific and is stored at -30 degrees centigrade, has a shelf life of 1 year Thawed before use at 37 degrees centigrade.

Indications for use

1. Replacement of clotting factors following DIC (factor eight), Liver disease, deficiency of vitamin K dependent on clotting factors, overdose of oral anticoagulants (warfarin), massive transfusion of stored blood 2. In treatment of diseases such as haemophilia when specific preparations are not available ic. factor eight

3. To replace other plasma constitutes such as Fibronectin (în septicaemia and delayed wound healing)

CRYOPRECIPATE

A plasma component containing factor eight and fibrinogen, obtained from a single donation of fresh plasma by rapid freezing within 6 hours of collection This frozen plasma is subsequently thawed at 4-8 degrees centigrade and 20ml of supernatant is removed, this is then refrozen and stored for up to one year at -30 degrees

Uses:

Treatment and prevention of bleeding in haemophilia and Von Willebrands disease

Treatment of factor eight deficiency following massive blood transfusion In treatment of intractable bleeding in uraemia and some platelet function disorders.

OTHER PLASMA PRODUCTS

Factor VI11 concentrate - Hemophilia A Factor IX concentrate - Hemophilia B

Both prepared from large pools of plasma by fractionation, stored at a freeze dried preparation for reconstitution with sterile water.

PLATELET CONCENTRATES

Advances in cytotoxic chemotherapy have increased the demand for platelet transfusion. Platelets are ideally prepared from blood which is less than 24hours old - in practice blood up to 72 hours old is used Wide variety of platelets available, differences arise in methods of separation.

Platelets may be harvested from single units or a pool of 4-6 units Once harvested life is 5-7 days

Transfusion is normally by special giving set There is always some contamination of platelets with donor red cells so

platelets should be ABO &Rh compatible In emergency incompatible platelets can be used HLA matching important in certain types of patients ie bone marrow

transplant or those previously sensitized as a result of repeated previous

transfusions Platelets play important role in haemostasis by forming platelet plugs and

by releasing activators in the clotting cascade Normal platelet count is 150-400

Platelet counts below 20 are associated with spontaneous bleeding Platelets are often required inpatients who are actively bleeding and have counts less than 50.

Low platelet counts - thrombocytopenia - result from: Dilution with massive blood transfusions due to low count in administered blood .

Excessive consumption as in DIC.

Hyperspleenism Liver disease.

Bone Marrow Depression following radiotherapy or cytotoxic chemotherapy

COMPLICATIONS OF BLOOD TRANSFUSIONS

HAEMOLYTIC REACTIONS:

Destruction of donor cells by antibodies in the recipients plasma Usually immediate but may be delayed for 1-2 weeks when an antibody that was not present at time of transfusion develops rapidly - this only occurs in patient who has bee previously transfused

Immediate reactions are due to antibodies present at time of transfusion and should be detected by cross matching Usually due to ABO incompatibility Commonest cause of such reaction is failure of labeling or checking of the donor blood

Symptoms:

Restlessness, breathlessness, retrosternal or anginal pain, abdominal or

lumbar pain, throbbing headache, rigors

Signs of cardio-respiratory collapse, renal failure &DIC

Treatment:

Stop transfusion, support circulation with plasma expanders Use of steroids and antihistamines.

Urine output maintained with diuretics and dopamine

Minor transfusion reactions:

More common

Usually present with pyrexia, nausea, diarrhoea, pains in chest and abdomen.

Treatment:

If mild, slowing of transfusion and use of antihistamines and paracetamol Incidence of minor reactions reduced by the use of inline filters or by using washed cell preparations

CHANGES IN BLOOD DURING STORAGE

RED CELLS

Rapidly lose ATP & 2,3-DPG. Adenine is added to transfusions to help maintain RBC ATP. Effects the ability of blood to transport oxygen Potassium leaks out of RBC, after 10 days the potassium concentrate rises to 15mmol and there is a risk of toxic hyperkalaemia following rapid massive transfusion and if serum potassium is already raised. ie renal failure

During storage red cells metabolisr ATP and produce lactic acid. The stored blood becomes progressively more acidotic - pH falls to 6.4 after 3 weeks storage. A very rapid transfusion may produce metabolic acidosis. However as each mmol of the citrate anticoagulant is metabolised 3mmol of bicarbonate are produced and a progressive metabolic alkalosis is the expected outcome.

WHITE BLOOD CELLS

Granulocytes begin to lose their phagocytic and bactericidal properties within 4-6 hours and are totally nonfunctional after 24 hours. They retain their ability to sensitize the recipient and may cause a febrile transfusion reaction. The incident of this is reduced by blood filters during transfusion. Some lymohocytes may remain viable for 2-3 weeks. This can be a problem in patients who have had bone marrow transplants. Blood products for these patients are irradiated to destroy these lymphocytes.

PLATELETS

Lose their haemostatic function within 24 hours.

COAGULATION FACTORS - 11, V & V111 and to a lesser extent XI rapidly become inactive - less than 50% active within 48 - 72 hours

MICROAGGREGATES Of old platelets, WBC, Fibrin strands and cellular debris are produced during storage. These can be removed by in line filters but tend to pass through the giving set filter.

The use of blood filter is controversial, accepted indications are for cardiopulmonary bypass, when transfusions are expected to exceed 5 units, patients who receive regular transfusions or who had febrile reactions to previous transfusions.

A problem of inline filters is that packed cells do not readily pass through them and this can be a problem during rapid transfusion. Fortunately most aggregates in packed cells are removed by a standard giving set filter. In line giving sets MUST NOT BE USED for platelets as they will filter 30% of the platelets. Platelets are usually given with a special giving set. A clean conventional giving set can be used in an emergency as the normal filter will only remove 3% of the platelets.

Indication of Blood Transfusion(B.T)

-Hb%

-Haemorrhage 

-major surgery

-Road Accidents.

-Haemolytic Diseas in neborn

-Thalasemia mejor

-Alpha thalassemia

-Beta thalassemia

-Destruction of red blood cells

-In CICU

-Drais 1.

-FFPs

 -white blood

 -Pus Cells

 -LVF CRF 

 -iron Daficimy

 -Hypovolemia