How Blood Transfusions Work

Blood transfusion is commonly used in case of fatal blood disorders, illness and excess blood loss during injuries or surgeries. How blood transfusions work and help a person to survive in such dreadful situations is the topic which we will discuss in this article.
The human body consists of approximately 4 to 6 liters of blood. A normal, healthy, adult male usually has 5.6 liters of blood and female has 4.8 liters of blood, (approximate values). Though this amount may vary from one person to the other, low blood may cause various complications and may even be life-threatening. There may be a lot of reasons behind the decreased amount of blood. It can be due to some injury or because of some illness. In such situations it becomes important to get blood from a donor to maintain the optimal amount of blood in the body. The process of transferring blood from the donor to the receiver is known as blood transfusion. Human beings have 8 types of blood groups, hence it is very important to match the blood group before transfusion.

How a Blood Transfusion is Performed

Human blood has four components: red blood cells, white blood cells, platelets and plasma. Blood transfusion can be the donation of whole blood or any individual components like plasma or platelets or just the white blood cells. Hence, transfusion may not necessarily be related to blood donation. The rest of the amount is again transfused into the donor’s body. But blood transfusion can be done only when the donor’s blood group matches that of the recipient. If the donor’s blood does not match with the recipient’s, blood will agglutinate and will clog the vessels which will hinder circulation. This may even result in death.

Process of Blood Transfusion
The process is simple yet there are few important steps to follow before transferring blood. Following are the steps which are followed in the process of blood transfusion.

The process starts from the very first step of getting blood. You can get blood either from a blood bank or from a donor.
In case of donor, you have to get the blood tested before taking it. The donor needs to undergo some tests like HIV test, hepatitis B, hepatitis C, syphilis, etc., which are mandatory before the donation. The medical history of the donor is moreover an important factor which is considered.

The donor’s blood group should match the recipient, which is done by a simple test. The blood is tested in an in-vitro state and is matched with the recipient’s blood. The plasma is moreover matched separately in order to avoid complications. If the blood group is matched, blood will easily mix with the sample of the recipient’s blood yet if it doesn’t, it can agglutinate.
Once the blood unit is considered safe for transfusion, the required amount is taken from the donor. Generally, a person can donate 1 unit of blood (450ml) at one time yet if the donor is healthy, he can even donate up to 2 units. In case more blood is required, multiple donors are arranged. The collected unit should be used within four hours to avoid infection.
If only the plasma or any particular component has to be transferred, blood is taken from the donor and then with the help of a centrifugal machine, plasma is separated from the blood and the rest of the blood is transfused back into the donor’s body.
The obtained blood is transfused with the help of a tiny tube called a cannula. It is inserted into the vein of recipient’s arm. The cannula is connected to a drip, which is further connected to a blood bag through which it is transferred.
During transfusion, the recipient is closely observed to ensure any adverse reactions of the blood unit. If any problem is observed immediate action is taken.
After the transfusion the receiver often feels energetic and better due to the increased amount of oxygenated blood in the body.

Though most of the people do not show any signs of discomfort at the time of transfusion or even after that, 1% to 2% of the people show side effects such as chills, allergy, fever, etc., which can be overcome with the medication prescribed by the doctor. So in future, if your doctor advises you to undergo any type of blood transfusion, discuss all the details and let him know about your medical history and allergies if you have any. Doctors and researchers are trying their best to make blood transfusion safer day by day. To conclude, we can say that in spite of all the risks and side effects involved in the blood transfusion process, it can save lives.