What is blood transfusion?
Blood transfusion is the process by which blood is given intravenously, to replace blood that has been lost through surgery, or trauma, or as a result of a medical requirement.

What is the purpose of blood transfusion?
Blood is a complex substance responsible for transportation, regulation and protection in the human body through a network of arteries, capillaries and veins. All of the functions are important but too numerous to be listed here. However, worth a mention is how blood provides oxygen to the tissues. Blood loss is coupled with the body's decreased capacity to deliver oxygen. Patients can feel exhaustion, even at rest.

Your blood allows oxygen to be delivered to your body’s tissues and organs and for waste products, such as carbon dioxide, to be removed and discarded. This process is essential for tissue survival and function and for recovery after surgery. The purpose of a blood transfusion, is amongst other things, to replace lost blood, and to help ensure that oxygen transportation and transfer continues to be carried out effectively by the body.

What are the most common blood transfusion options?
Donor / Banked blood (also known as Homologous or Allogenic blood)
The most common method of performing blood transfusion in the UK today is by using ‘donor’ blood. This is blood that has been collected by public donation, processed and then stored under controlled conditions until it is required for transfusion to a different recipient.
The processing performed on this type of blood includes screening for blood borne diseases such as HIV and Hepatitis B and is, therefore, generally regarded as a safe and effective method of transfusion.

To make sure the correct blood type is given, the Donor blood is "cross-matched" with the recipient. This ensures that no severe reactions occur on transfusion. However, errors, although very rare, are known to have occurred in the past (1)

Autologous Blood Transfusion or ABT (sometimes referred to as Autotransfusion)
There is another, safer, option that can be used for some operations. This option is known as Autologous Blood Transfusion, or ABT for short, and is the name given to the process through which the patient's own blood is re-infused by transfusion. Blood can be taken from a patient either during the surgical procedure itself (Intra-operative collection), or, after surgery (Post-operative collection).

Autologous transfusion is particularly suitable if you are scheduled to go into hospital for non-emergency surgery, and have the opportunity to decide in advance to have your own blood re-infused. This may be the case, for example, with total knee and total hip replacement surgery. For total knee replacement surgery, post-operative collection is particularly appropriate as the majority of blood loss occurs after completion of the operation.

“Post operative ABT can only be used in certain orthopaedic procedures such as Total Knee Replacements but offers multiple benefits.  It reduces the risk of people receiving the wrong blood, minimises adverse reaction, limits the demand on blood-bank stocks and the equipment involved is uncomplicated and easy to use.”
Steven Boxall, Clinical Manager for Pathology at the Royal United Hospital in Bath

(1) www.shotuk.org