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Even in the most ancient times, people realized that large blood losses are fraught with death. In our time, transfusion is perceived as the most common medical procedure. But mankind has come to this knowledge through a long path of trial and error.
There was a time when our ancestors even drank the blood of animals, hoping in this way to restore their own reserves. In the XNUMXth century, healers first tried to transfuse blood. But then they used animals as “donors”. It is clear that such experiments did not end in anything good. It was only in the XNUMXth century that doctors realized that only human blood could save a patient’s life. Although then they still did not know about the existence of groups and Rhesus.
The mass practice of more or less professional transfusion began to be applied only during the First World War. And by the way, it was at this time that the first myths about donation and transfusion were born, many of which are common even in our time.
Research on the benefits and harms of blood donation has been going on for a long time. Scientists around the world set themselves the task of determining how regular blood loss affects human health, how quickly his body recovers after the procedure.
What is donation
Donation is the voluntary donation of one’s own blood in favor of another person who needs it for treatment. The term is based on the Latin donare, which translates as “to give.”
Few people know, but donation is different. A person can donate either a certain amount of blood in its entirety, or only its individual components. Regardless of the type of donation, before the procedure, the donor must undergo a medical examination and pass tests.
Types of donation
By purpose
Blood can be donated for different purposes and for different reasons. Based on this, donation happens:
- Target – a donor donates blood, usually urgently for the treatment of a relative or another person after heavy bleeding (after an accident, surgery).
- Allogeneic – donated material goes to the blood bank and then used for patients who need transfusion.
- Autologous is a type of donation when blood is taken from the patient himself before the operation, and after it the taken material is poured back into the donor.
- Substitute – in this case, the donor donates blood to replace the material previously taken from the general bank for a sick relative.
According to delivered material
Depending on the circumstances, a donor can donate whole blood or only certain components of it.
Whole blood donation
The amount of blood a donor can donate at one time may vary slightly from country to country. In Russia, for example, 450 ml is considered the norm, while in the USA it is 480 ml, which is equal to 1 pint. The procedure usually takes no more than 15 minutes. After it, the donor is fully restored after an average of 8 weeks.
Plasmapheresis
During this procedure, the donor donates only plasma. To do this, they first take whole blood from him, then centrifuge it and separate the plasma from the cell mass. The liquid part is taken, and the thick components are diluted with saline and injected back into the donor’s vein. For one procedure, without harm to health, you can take up to 600 ml of plasma. The procedure lasts approximately 1 hour. Full recovery after plasmapheresis occurs after 2 weeks.
Donation of immune plasma
As in the previous case, only plasma will be required from the donor. But most importantly: it must contain antibodies to a specific virus or bacterium. In order for the donor to contain these antibodies, before the procedure, he must receive the necessary vaccination. That is, a special vaccine is introduced into his body, which provokes the production of antibodies and the formation of immunity to the disease.
Thrombocytapheresis
Platelets are extracted from the taken blood, after which the remaining components are injected back into the donor. This procedure is somewhat more complicated than plasmapheresis or whole material donation. At one time, up to 450 ml of platelet mass can be taken from the donor. The procedure takes about 2 hours. The recovery will take within 2-3 weeks.
Erythrocytapheresis
The procedure is carried out similarly to plateletpheresis, but not platelets are extracted, but erythrocytes – red blood cells (erythromass). Erythrocytapheresis lasts within 30 minutes. After the procedure, the donor recovers within 1 month.
What happens to the body after donating blood
On average, the body of an adult contains about 5 liters of blood. That is, after 1 procedure, the donor loses almost 10% of its original composition. In addition, in the case of the delivery of whole material, the amount of heme in his body decreases by almost 225-250 ml. Experts call heme a combination of ferrous iron and porphyrin. These substances form the core of hemoglobin and are responsible for transporting oxygen throughout the body. That is, after donating blood, the oxygen exchange in the donor’s body worsens. How dangerous is it? If heme losses do not exceed 250 ml, then the body copes with this quite easily, activating its own compensatory mechanisms.
In the aorta and carotid artery there are special baroreceptors that fix the pressure inside the vessels. When the volume of blood in the vascular system decreases, they transmit special impulses to the heart and lungs, causing them to work more actively.
After the donation procedure, the body produces more actively antidiuretic hormone, which is responsible for the regulation of fluid in the body. Thanks to its activity, the vessels narrow slightly and the pressure in them is restored. When a person loses a certain amount of blood, there is a surge of another hormone in his body – erythropoietin, which activates the formation of red blood cells. Thus, in the human body, a chain of mechanisms is launched to quickly restore losses.
Donation: benefits for the body
As a rule, donor blood is needed:
- patients with multiple severe burns;
- patients with large blood loss during an accident, trauma, surgery, childbirth;
- pregnant women with severe toxicosis;
- persons with severe anemia;
- patients with hematological or purulent-septic diseases;
- people with severe bleeding, etc.
In such cases, the donor’s blood can save the life of the recipient. But, as they say, there is another side of the coin: are there any advantages from donating blood for the donor himself.
Even in ancient times, folk healers used bloodletting to treat various diseases. Although in fact in many cases this procedure was inappropriate and did not affect the course of the disease in any way, the body can still receive certain advantages from small blood losses.
- Reducing oxidative stress.
Experts who have studied the effects of donating blood on the body of a donor have found that this procedure helps to reduce the amount of iron in the body, and with it, reduce oxidative stress. It turned out that after the loss of a certain amount of blood in the body, the amount of an enzyme with a complex name, superoxide dismutase, increases. This substance inhibits activity or even destroys reactive oxygen species that have a detrimental effect on humans. And since oxidative stress is considered one of the causes of malignant transformation of cells, this fact allowed scientists to look at donation as a prevention of various types of cancer. According to the results of a study that lasted almost 5 years, American scientists suggested that for the prevention of cancer, including the liver, throat, lungs and intestines, it is useful to be a donor twice a year.
- Reduces the risk of cardio diseases.
By observing donors, scientists concluded that donating blood helps reduce the risk of cardiovascular disease. Statistics says that donors are almost 80% less likely to suffer from cardiac disorders than other people.
First, donation helps lower blood pressure. Secondly, it is known that one of the factors causing cardiac disorders is increased blood viscosity (the so-called “thick blood”). In such people, the circulation in the vessels is disturbed, the risk of blood clots, blockage of the arteries increases, which can cause sudden death. But as it turned out, regular blood donation reduces its viscosity, which reduces the risk of heart attacks and strokes. Proponents of this theory argue that a beneficial effect on the cardiovascular system will be noticeable if you undergo the procedure at least once a year.
- Prevents autoimmune diseases.
Donation helps to reduce the amount of proteins in the body responsible for inflammatory reactions. When these proteins accumulate excessively, there is a risk of damage to cell membranes, and the development of processes leading to autoimmune diseases is also possible. An excess of these proteins can cause cancer, type 1 diabetes, rheumatoid arthritis, Alzheimer’s or Parkinson’s disease, and accelerated aging. Donation can protect against all this.
- It contributes to weight loss.
According to scientists from the University of San Diego (USA), during the donation procedure, a person loses more than 650 calories. That is, regular blood donations can be useful for overweight people. But at the same time, frequent blood donations may be contraindicated for people with normal or underweight.
Can donation be harmful?
If a person does not have serious health problems, then a one-time donation of blood will not harm him. According to experts, negative side effects of donation occur in only 2 out of 100 people. The most common side effect is fainting. After the procedure, a person may lose consciousness due to the resulting drop in blood pressure.
The question of whether regular blood donation can be harmful or dangerous is of concern to most people who have to donate blood. Moreover, in our time, experts have refuted the theory that this procedure helps to renew the blood. On the contrary, you can often hear that regular donation is addictive, although it has already been proven that this is a myth. Certain risks of such a procedure, of course, exist, although much of what the donation actually threatens is often greatly exaggerated.
- Anemia.
Uncontrolled blood donation is always a risk of developing iron deficiency, as well as a lack of other components, without a sufficient amount of which anemia develops. You can prevent this danger if you eat a balanced diet before and after the procedure, and also do not become a donor too often.
- Capillary permeability deteriorates.
Regular bloodletting impairs the permeability of the capillaries that supply blood to the pulmonary alveoli. The researchers made this assumption after observing donors with many years of experience.
- Increases the risk of neoplasms.
Although this theory does not yet have scientific confirmation, some groups of scientists are still confident that frequent blood donations activate the proliferation process in the body. This term refers to a state in which cells actively multiply by dividing, thereby causing tissue growth. When a person regularly donates red blood cells, new red blood cells are more actively formed due to proliferation. But, according to scientists, blood donation activates the accelerated growth of not only red blood cells, but also cells of malignant tumors (if any) in the organs involved in hematopoiesis. And this is red bone marrow, lymph nodes, thymus gland, spleen.
How to properly prepare for blood donation
To minimize the risk of side effects from donation, it is necessary to properly prepare for the procedure in advance. The day before, the donor needs to avoid heavy physical exertion, as well as have a good rest (in this regard, good sleep is very important).
It is strictly forbidden to donate blood on an empty stomach. For breakfast, it is good to choose foods rich in carbohydrates, including sweet tea and a high-calorie dessert. But there are some restrictions regarding food. 24 hours before the delivery of the material and immediately before the procedure, it is forbidden to consume the following products:
- eggs;
- meat;
- cottage cheese;
- milk;
- nuts;
- sausages and smoked meats;
- chocolate;
- bananas;
- dates;
- vegetable and butter;
- fast food.
To avoid dizziness, after donation, lie down or sit for at least 15 minutes. During this time, blood pressure will have time to level off. After the procedure, you should not load yourself physically and go to the bath. During the day you need to drink plenty of water. This helps to quickly restore fluid reserves in the body. The diet on this day should be balanced and high-calorie.
Absolute contraindications to donation:
- oncological diseases;
- radiation sickness;
- infectious diseases;
- cardiovascular diseases;
- the presence of parasites;
- diseases of the digestive tract;
- disturbances in the work of the kidneys or liver;
- bronchial asthma;
- skin diseases;
- blindness and other eye diseases;
- osteomyelitis;
- recent surgery.
Time limits for donation:
- age up to 18 years and after 60 years;
- body weight below 50 kg;
- pregnancy (within 12 months after childbirth);
- breastfeeding (3 months after the end);
- tooth extraction (10 days);
- taking antibiotics (14 days);
- vaccination (up to 12 months);
- drinking alcohol (48 hours);
- visits to Africa, Asia, Central or South America (3 years);
- recent tattoo, piercing (within 1 year);
- undergoing acupuncture procedure (within 1 year).
Myths about donation
1. During the procedure, you can become infected with some kind of disease
Actually, this is an absurd assumption. In any clinic, disposable sterile systems are used for blood sampling. They must be packed in a sealed container and opened immediately before the procedure in the presence of the donor. This is the main guarantee of safety for the donor.
2. Donation takes a long time
If a person delivers whole material, then the whole procedure takes no more than 10-15 minutes. More time will be required if only individual components are to be extracted from donated blood.
3. It hurts
The only painful moment of the procedure is the piercing of the skin and puncture of the vein on the inside of the elbow. By the strength of the pain, these sensations are compared with a pinch. Otherwise, the procedure does not bring pain.
4. Smokers cannot be donors
Smokers can donate blood, but they will have to refrain from bad habits for at least 24 hours before the procedure and 1 hour after it.
5. Regular blood donation is addictive.
If a person is healthy, then even repeated surrender will not cause such an effect.
The opinions of experts on the benefits and harms of donation are very contradictory. There are research results both confirming the advantages of the procedure and indicating that regular donation may be unsafe for a person. We have reviewed the most common theories about the potential harms and benefits of the procedure. But still, it is always necessary to take into account the individual characteristics of the organism and the state of health of the donor.