What is it Blood transfusion?
Our patients with oncology and hematology diseases frequently needs blood transfusions.
Blood transfusion is a common procedure in which you receive blood components through an intravenous (IV) line inserted into one of your blood vessels.
Blood components are: red blood cells, plasma, platelets, cryoprecipitated anti-hemophilic factor, sometimes whole blood.
Studies worldwide have shown that voluntary blood donors from low-risk populations are the foundation of a safe and sustainable blood supply.
All donors are also carefully screened using a comprehensive health assessment questionnaire.
Every unit of donated blood is managed under a comprehensive quality system benchmarked against stringent internationally recognized standards.
All blood units are tested for Hepatitis B, Hepatitis C, HIV, and Syphilis, using the most sensitive methods available.
The ABO group or blood type - O (I), A (II), B(III), AB (IV) and Rhesus type (positive or negative) are tested and confirmed on every unit to ensure that the donated blood is given to a patient with a compatible blood type.
The decision on which patients require a transfusion and the transfusion amount is ultimately a clinical one made by a registered medical practitioner.
The Blood Transfusion Process
1. A blood sample will be taken to confirm your blood group. You may therefore have to wait for some time for these tests to be completed, but they are necessary to ensure your safety.
2. Before the red cell transfusion is carried out, the donor’s blood is tested (called cross-matching) against your own blood sample to ensure that the red cells to be transfused are compatible your blood.
3. Before the transfusion starts, your identity will be carefully checked against the identity written on the unit of blood assigned.
4. This is why the nurse of doctor will ask you to state your name and identification details when taking a blood sample and prior to transfusion.
5. A blood transfusion is usually given through a small tube inserted directly into a blood vessel in the arm.
6. In adults on average, it takes about one to two hours for each unit of red cells to transfused, and about 20 to 30 minutes for each unit of platelets or plasma.
7. Because of the risk of bacterial infection or deterioration of the blood components when they are exposed to room temperatures, transfusion should not take more than three hours.
8. A doctor and a nurse will monitor your general condition, temperature, pulse and blood pressure before the start of the transfusion, and will continue to monitor this several times during the transfusion.
9. If you feel unwell or become uncomfortable during or just after the transfusion, please notify the nurse immediately.
Blood Transfusion Risks
However, in spite of the stringent measures in place, there is still a very small percentage of risk of possible complications from blood transfusion.
Transfusion – Transmitted Infections These could be due to: Infectious Window Period: In the early stages of infections such as HIV, Hepatitis B and Hepatitis C, there is a window period when the blood is infectious, but the level of virus is too low to be detected by available laboratory tests. The current risks of contracting major infections through a blood transfusion in developed countries have steadily decrease over the year and are now very low.
Reactions to Blood Transfusion and Other Complications There are patients who may occasionally experience mild reactions or serious complications after undergoing blood transfusions. These may appear during the transfusion or for certain reactions, within six hours after completion of the transfusion. a) Mild Reactions Mild reactions usually subside quickly after the transfusion is stopped and can be easily treated with medication. Most reactions that occur are mild in nature. Some examples of mild reactions are rashes or urticaria (about 1 to 3% of transfusions) and fever (about 0.1 to 1% of transfusions). b) Serious Complications Serious complications are very rare but may include the following: Excessive fluid in the body and lungs which leads to shortness of breath (less than 1% of transfusions). Patients with heart or kidney problems may be at greater risks. Transfusion Related Acute Lung Injury (TRALI) leading to difficulty in breathing (less than 0.02% of blood transfusions). Severe allergic reaction which may be life threatening (less than 0.005% of blood transfusions).
Bacterial infections (less than 0.002% of transfusions) which may be life-threatening and may be unavoidable despite all stringent precautions taken.
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Reference: Roback, Combs MR, Grossman B, Hillyer C. Technical Manual, AABB press 16th edition, 2008; Provan D, Singer CRG ect. Oxford handbook of Clinical Heamatology, 3d edition, 2011.