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This application is a service of the Singapore Government.

Health Sciences Authority

Blood Transfusion

blood transfusion1

While the risk of catching a blood-transmitted disease or suffering an allergic reaction after a blood transfusion is very small, it is still a significant factor. Thus a blood transfusion, though often life-saving, should only be done when necessary.

Your doctor will weigh the risks of giving you a blood transfusion against the risks of not doing one. The decision to give a patient a blood transfusion is made only after careful consideration.

Find out when you might need a blood transfusion.

To understand the blood transfusion process and its possible risks, please read the patient information leaflet (available in four languages):

The Risks of a Transfusion

Overall, a blood transfusion is very safe. Only donated blood that matches your blood is used.

However, there is a small risk of complication such as catching an infection, having an allergic reaction to the donated blood or being given blood of the wrong blood group. Fortunately, severe reactions to blood donations are very rare. Hospital staff are also trained to recognise and manage such reactions.

Major infections that can be spread through a blood transfusion are Hepatitis B, Hepatitis C and HIV.

The risks of contracting major infections through blood transfusion are small. The current estimated residual risks in Singapore are:

  • One per 110,000 donations for Hepatitis B;
  • One per 1,300,000 donations for Hepatitis C;
  • One per 1,100,000 donations for HIV.

Many precautions are taken to ensure that blood transfusions are as safe as possible:

  • All blood donors are unpaid, altruistic volunteers;
  • Health of donors is carefully screened using a comprehensive health assessment questionnaire to identify anyone who may pass on an infection;
  • All blood units are managed under a comprehensive quality system benchmarked against stringent internationally recognised standards and tested for certain infections using the most sensitive methods available;
  • Any unit of donated blood that fails these tests is discarded.

The blood is dripped directly into a vein in your hand or arm using a needle. It takes an average of two to three hours to transfuse one bag of blood.

In addition, hospital staff will make careful identification checks before a transfusion to ensure that you receive the right blood. You will also be regularly monitored during your transfusion to make sure you are well.

Alternatives to Blood Transfusion

Discuss with your doctor why you need a transfusion and explore the alternative treatments available. A blood transfusion should only be given when there are no other alternatives.

For some conditions, there are safer options available.

For example, most people cope well with mild to moderate amounts of blood loss, or with mild anaemia. A blood transfusion may not be necessary. Instead, the lost fluid can be replaced with a salt solution, while the body will regenerate new red blood cells to replace what is lost. Iron supplements can also be taken to aid recovery, as iron is an important raw material in the production of red cells.

Those going for elective surgery can also consider an Autologous Blood Transfusion.

What Happens During a Blood Transfusion?

Most people feel no different when receiving a blood transfusion.

The blood is dripped directly into a vein in your hand or arm using a needle. It takes an average of 2-3 hours to transfuse one bag of blood.

Some people, however, might develop a slight fever, chills or a rash. These symptoms are usually due to a mild immune reaction or allergy. Fortunately, they are easily treated with medication or by giving the blood more slowly.

Will I Need to Pay for the Blood I Receive During a Transfusion?

You do not need to pay for the blood you receive during a transfusion. Blood is never sold. This is because blood donations are voluntary and donors do not receive any form of payment.

As a patient, you will only need to pay for a blood processing fee. This is to recover costs for collecting, processing, testing each unit of blood to ensure it is safe for transfusion.

Patients who are citizens need only pay a portion of the blood processing fee which is subsidised at two levels:

  1. The Ministry of Health subsidises the costs incurred by the blood bank in processing the blood.
  2. There is a further subsidy at the hospital level, depending on the patients' ward class.

Patients who are Permanent Residents will also be subsidised, but at a lower level than for citizens.

Please see the following chart and table for an illustration of the cost involved in processing a unit of whole blood:


The Health Sciences Authority (HSA) aims to supply the safest possible blood to all patients who need a blood transfusion. All donated blood collected is therefore sent for processing and testing at the HSA's laboratories before it is transfused to patients.

These are the key processes and tests performed on all donated blood:

  • Blood component processing: To optimise blood usage and to benefit more patients, every pack of blood collected is processed into different components e.g. red blood cells, platelets and fresh frozen plasma. Each of these components can be given to different patients with different medical needs.
  • Infectious diseases testing: Some diseases can be transmitted through blood transfusion. This means that patients receiving blood from donors with certain health conditions may become infected. All donated blood is therefore screened for infectious diseases such as HIV, hepatitis B, hepatitis C and syphilis. Selected components or units may also be tested for malaria or bacterial contamination.
  • Blood group testing: This ensures that the donated blood is given to a patient with a compatible blood type.
  • Antibody screening: This ensures there is no high level of abnormal antibodies in donated blood which may harmful to a patient following a transfusion.
  • Storage of blood products: All blood products must be stored under carefully monitored and controlled temperatures and conditions. This ensures that they are in an optimal state when transfused to patients.