BLOOD TRANSFUSION

Is applied to transfer of blood from one living subject to another under certain strict rule.

Attempts to transfuse blood were made from fifteenth century.

In 1901 LANDSTEINER discovered safe transfusion of blood of a major human ABO group.

Now a days blood can be separated into its components for individual use.

-       RBC

-       Platelet concentrates

-       Fresh Frozen Plasma

-       Cryoprecipitate

-       Albumin

-       Factor VIII and combination factors are also available.

SAFE TRANSFUSION OF BLOOD NEEDS –

“PRESELECTION AND SCREENING OF DONORS AND DONATED BLOOD” is crucial for blood borne pathogens.

Fatal complication may occur from error of labeling blood sample from patients and incorrect patient identification.

BLOOD BANK

A blood bank transfusion service is the system with which most blood transfusion is arranged for necessary laboratory investigations, collection, storage and compatibility testing of blood.

TWO most common causes of serious reactions are i. either incorrect labeling of blood sample sent from a pt. for cross matching and ii. Failure to ensure that the blood from the blood bank is administered to the correct patient.

Blood group ‘O’ (-)ve can be transfused without cross matching in urgent need.

But previous transfusion may cause reaction.

BLOOD GROUP – The term blood group is applied to the genetically determined antigens that can be detected on the RBC surface by specific antibodies.

The locus for each blood group system is situated on an autosome: ABO locus on chromosome 9, Rh locus on chromosome 1.

SL No.	Blood group	Frequency	Antibody (Normally present on serum)
1	O	45%	Anti- A and Anti -B
2	A	40%	Anti- B
3	B	10%	Anti – A
4	AB	5%	None

Indications for blood transfusion in surgical practice are as follows:

-       Following traumatic incidents associated with severe blood loss, haemorrhage from pathological lesions as in Haematemesis and Melaena from G.I. tract.

-       During major operative procedure for example cardiac surgery.

-       Following severe burn.

-       Post operatively in a pt. that has become severely anaemic.

-       Pre operatively in chronic anaemic pt. needs urgent surgery.

-       To arrest haemorrhage or as prophylactic measure prior to surgery in a pt. with a haemorrhagic disorder.

BLOOD COLLECTION

Blood is collected into a sterile commercially prepared plastic bag with needle and plastic tube attach in a completely closed sterile unit.

PROCEDURE

With the donor lying on the couch a sphygmomanometer cuff is applied to the arm and inflates to a pressure of 70-80 mm Hg.

After introducing 0.5 ml of L/A a 15 G needle is introduced into the median cubital vein and 410 ml of blood is allowed to pass into the bag containing 75 ml of anti coagulant, CPD (Citrate Phosphate Dextrose).

During collection the blood is constantly mixed with the anticoagulant to prevent clotting and at the end of the procedure the tube is clamped and the needle is removed.

BLOOD STORAGE

All blood for transfusion must be stored in a special blood bank refrigerator controlled at 4º C (2-6). Blood is allowed to stand at higher temperature for more than 2 hrs is in danger of transmitting infections.

Life span of storage blood

CPD: Blood has a shelf life of 3 (three) weeks.

CPDA: (Citrate phosphate dextrose Acid has a half life up to 5 weeks)

RBC: suffers a temporary reduction up to 72 hrs.

WBC: rapidly destroyed in stored blood.

Platelets: considerably reduces, a few are functionally useful after 24 hours.

Clotting factors: VIII & V are labile & their levels fall quickly.

SAG-M blood: All the plasma is removed from one unit of blood & replaced with 100 ml of crystalloids solution containing-

1.      NaCl                            - 877 mg

2.      Adenine                       - 16.9 mg

3.      Glucose anhydrous      - 181 mg

4.      Mannitol                      - 525mg

SAG-M blood maintained good cell viability but the product contains no protein is to priority for anemic patient. Every two units of blood transfusion should be supplemented with 400 ml (4.5%) of human albumin.

Giving blood: Blood grouping & cross matching needs full laboratory procedure and it takes one hour. Blood transfusion is commenced by –

1.      Selection & preparation of the site.

2.      Careful checking of the donor blood. This should bear a compatibility label stating the name of the patient, hospital reference no., ward and blood group.

3.      Insertion of the needle or cannula – the later may be maintained for any duration of time.

4.      Giving detailed written instruction as to the rate of flow – usually in four hours. But in emergency as per requirement.

Warming blood: Must be warmed to body temperature before transfusion.

Filter blood: Platelet aggregate and leucocytes membrane – 40 micrometre.

Complications of blood transfusion:

Ø  CCF(Congestive Cardiac Failure)

Ø  Transfusion reaction

Ø  Infection (Viral, bacterial, parasitic)

Ø  Thrombophlebitis

Ø  Air embolism

Ø  Coagulation failure