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Blood transfusion
1.
2. Introduction
Blood transfusion can be life-saving & many
areas of surgery could not be undertaken
without reliable transfusion support.
Tansfusion of blood & its components carries
potential risks, which must be outweighed by
the patient’s need.
6. Blood Group Systems
There are more than 400 blood groups have
been found
The two major blood groups:
(1) ABO system
(2) Rh system
Others:
(Kell, Duffy, Kidd)
7. ABO System
Phenotype Antigens Naturally Frequency (%)
occuring
antibodies
O O Anti-A & Anti-B 46
A A Anti-B 42
B B Anti-A 9
AB AB Nil 3
8. Principles of Cross-match
Blood is selected on the basis of ABO & Rh D
group.
Check compatibility between potential donor
red cells & recipient serum.
Takes about 40 minutes.
O –ve group can be used in extreme
emergency situations.
9.
10. Fresh whole blood
Average volume of blood withdrawn is
470mls taken into 63ml of anticoagulant.
Refers to the blood that is administered
within 24 hours of its donation.
Rarely indicated.
Poor source of platelets & factor VIII.
11. Indications:
- Acute blood loss
- Sickle cell disease
- Cardiac surgery
12. Red cell concentrates
Product of choice for most clinical situations.
Concentrated suspension of RBCs can be
prepared by removing most of the
supernatant plasma after centrifugation.
The preparation reduces but does not
eliminate reaction caused by plasma
components.
Reduces Na+, K+, lactic acid & citrate
administered.
Provides oxygen-carrying capacity.
13. Indications:
- Severe anemia
- Haemolytic anemia
- Anaemia in pregnancy
14. Platelet concentrates
Made either from centrifugation of whole
blood or from an individual donor using
apheresis.
An adult dose is manufactured from 4
separate donations pooled together or 1
apheresis collection.
Carry a greater risk of bacterial
contamination as they cannot be
refrigerated.
15. Indications:
- Leukaemia
- Prophylactically to prevent bleeding in
patient with bone marrow failure
16. Fresh frozen plasma
Some 200-300ml of plasma can be removed
from a unit of whole blood.
Prepared by freezing the plasma from 1unit
blood at -30C within 6 hours of donation
Contains all the coagulation factors present in
plasma
18. Cryoprecipitate
A single unit of cryoprecipitate can be
removed from 1 unit of FFP after controlled
thawing.
After resuspension in 10-20ml plasma, the
cryoprecipitate is frozen once more to -30oc &
can be stored for up to a year.
Contains Factor VIII, fibrinogen &
von Willebrand factor.
Indication: DIC
19. Factor VIII and IX
concentrates
Freeze dried preparation of specific
coagulation factors prepared from large pools
of plasma
recombinant coagulation factor
concentrates , treatment of choice for
inherited coagulation factor deficiencies.
Haemophilia A (VIII)
Haemophilia B (IX)
20. Human albumin
Human albumin solution 20%
200 g/L albumin and 130 mmol/L sodium
Indicated for treatment of acute severe
hypoalbuminemia
21. Granulocyte concentrate
Prepared from single donor using cell
separatos and are used for pt with severe
neutropenia with evidence of bacterial
infection.
Numbers of granulocytes increase by treating
donors with G-CSF and steroids
22. Blood Storage
Blood products Storage Shelf life
Red cells 2-6 oc 35 days
Frozen red cells 2-6 oc 24 hours
Washed red cells 2-6 oc 6 hours
Platelet concentrate Room temperature 5 days
Fresh frozen plasma -20 to -40 oc 12 months
Cryoprecipitate -20 to -40 oc 12 months
Granulocyte concentrate Room temperature 24 hours
23. Types of Blood Transfusion
Homologous
– from a volunteer donor ; interval between 2
donations of at least 2 months
Autologous
– pre-operative collection & re-infusion on
requirement.
- possible if Hb > 11g%; No infection; Fit for
anesthesia.
24. Autologous transfusion
1. Pre-operative donation
2. Isovolemic haemodilution
3. Cell salvage
Pre-operative donation
- blood withdrawn pre-operatively & stored
for up to 35-42 days.
- up to 5 units of patient’s own blood made
available, with the last unit being collected
48-72 hours before surgery.
25. Isovolemic haemodilution
- restricted to patients anticipated with
significant blood loss (>1000ml).
- up to 1.5L of blood withdrawn + standard
anticoagulant replaced by saline to
maintain blood volume.
- fall in Hct reduces the loss of RBCs
- withdrawn blood re-infused either during or
after surgery.
26. Cell salvage
- blood collected from the operation site
either directly during surgery or by the use of
collection devices attached to surgical drains.
- during surgery, blood collected by suction
processed by a cell salvage machine
(anticoagulated + washed to remove clots &
debris) returned to patient
- post-operative drainage returned to patient,
most commonly not washed.