What are the precautions before donating blood

Although donating blood is a very meaningful thing, as a blood donor, you need to pay attention to some matters and taboos before and after donating blood. You cannot donate blood blindly. This is not only responsible for yourself, but also for others. Most people don’t know what precautions should be taken when donating blood. So what are the precautions before donating blood? The following are some things to note before donating blood for your reference, so that you won’t be in a rush when donating blood.

What are the precautions before donating blood?

1. The body's self-regulation after blood donation

Blood is composed of plasma, blood cells, etc., containing thousands of red blood cells, white blood cells, platelets and a variety of electrolytes. The blood of a normal adult accounts for about 7% to 8% of body weight, that is, there are about 70 to 80 ml of blood per kilogram of body weight. A healthy adult donates 200 to 400 ml of blood at a time, which only accounts for 1/25 to 1/20 of the total blood volume. The body can maintain normal function and metabolism through its own compensation. After blood donation, the water and electrolytes in the blood can be replenished through the infiltration of tissue fluid into the blood vessels or liquid beverages. Water and electrolytes can usually return to normal levels within 1 to 2 hours. After blood donation, the body's erythropoietin production increases, stimulating the proliferation and differentiation of bone marrow hematopoietic cell tissue, accelerating the production and release of red blood cells. White blood cells and platelets themselves have a short survival period in the body and are replaced quickly. As long as the blood donor has a reasonable diet before and after blood donation, the body can recover quickly.

2. Physical condition after blood donation

Everyone will experience discomfort such as drowsiness, chills, and anorexia after donating blood. This is a normal phenomenon. Don't worry about your poor physical condition. It's just that the degree of each person's performance is different. In addition to psychological factors such as tension and fear, this phenomenon is also related to the short-term shortage of red blood cells in the body after blood donation, which leads to a decrease in the body's oxygen supply. The function of red blood cells is to carry and transport oxygen. However, the more red blood cells, the better. Instead, the number should be maintained within a certain range. If there are too many red blood cells, the blood will become viscous and difficult to flow, and blood vessels will easily be blocked, causing cardiovascular disease. However, if the number of red blood cells is too small, their oxygen-carrying capacity will be reduced, causing people to enter a state of hypoxia and develop anemia, which can be life-threatening in severe cases. Some people worry that donating blood will cause a permanent decrease in red blood cells, affecting the functions of organs and tissues throughout the body. Even if you do not donate blood, about 3 million red blood cells die in the human body every day, and the same number of red blood cells grow. These new red blood cells are mainly produced by bone marrow hematopoietic cells and are always in a dynamic balance.

3. Things to note before and after blood donation

In order to ensure blood quality and eliminate adverse reactions to blood donation, pay attention to the following matters.

1. Things to note before donating blood

1) Eat breakfast

Do not go on an empty stomach the night before and the morning of blood donation. On the morning of blood donation, you should eat light food, such as porridge, bread, steamed buns, etc. Because the glucose level in the body will be relatively lower when the stomach is fasting, so as to avoid adverse reactions such as dizziness, palpitations, sweating, etc. during blood donation, but do not overeat.

2) Mainly vegetarian

A few days before donating blood, you should eat mainly vegetarian food and avoid eating high-fat, high-protein foods such as meat, fish, eggs, milk, soy products and greasy foods. After eating more greasy foods containing lipids, a large amount of lipid substances enter the blood. The blood line at this time is called fatty blood. Fatty blood is very dangerous when used as direct blood supply. After receiving this blood, the recipient is likely to have transfusion reactions such as chills and high fever, and even life-threatening.

3) Don’t drink alcohol

Do not eat too much the night before donating blood, do not drink alcohol or strong liquor during the first two meals after donating blood. It is advisable to eat light food and avoid eating meat, fish, eggs, milk, soy products and other foods to prevent blood turbidity and affect blood quality.

4) Prepare nutritious food

Before donating blood, you should prepare some foods that are high in nutritional value, easy to digest and absorb, and rich in protein, iron and vitamin C, such as milk, soy milk, eggs, bread, cake, ham and juice. After donating blood, you should eat immediately to quickly replenish fluids, energy and electrolytes.

2. Things to note when donating blood

1) Happy mood

You need to keep a cheerful mood at all times and clean your elbows under the guidance of the nurse. Place the arm with better exposed blood vessels at the elbow, and try to keep the arm from which blood is drawn in line with the heart to maintain smooth blood flow.

2) Relax your whole body

During the blood collection process, relax your whole body to avoid excessive pain caused by skin or muscle contraction that affects needle insertion. At the same time, you can actively consult the nurse about blood donation knowledge to enhance your understanding of blood donation knowledge.

3) Inner Peace

When donating blood, you must remain moderately quiet to reduce unnecessary irritability. If you experience any symptoms such as palpitations, shortness of breath, cold sweats, thirst, or restlessness, you should immediately tell the blood collection nurse or the visiting doctor so that appropriate measures can be taken.

3. Precautions after blood donation

1) Take breaks

You should pay attention to rest 1 to 2 days after donating blood, and it is best to ensure more than 8 hours of sleep a day. After donating blood, do not do heavy physical labor or strenuous exercise, give your body some time to adapt; do less mentally exhausting work such as studying, reading, watching TV, surfing the Internet, etc., and a good rest is like taking a tonic. After donating blood, you should also increase your water intake to replenish lost body fluids; you can also drink some brown sugar water to achieve the purpose of replenishing blood.

2) Don’t drink strong tea

It is best not to drink strong tea within one month after donating blood. Because tea contains more tannic acid, it easily combines with protein and iron to form precipitates that are not easily absorbed by the human body, affecting the body's absorption of protein and iron, and thus affecting the regeneration of blood cells in blood donors. Therefore, friends who have the habit of drinking tea should stay away from tea within one month after donating blood. Drinking some fruit juice (such as kiwi juice, orange juice, etc.) can not only relieve tea addiction, but also supplement vitamins and folic acid to promote the regeneration of blood cells.

3) No need for heavy supplementation

Do not over-supplement your nutrition. You can eat fresh fruits and vegetables, soy products, dairy products, fresh fish and shrimp, meat and eggs, etc., but there is no need to over-supplement and avoid overeating.

4) Eat more blood-forming foods

The main raw materials for hematopoiesis are protein, iron, vitamin B12 and folic acid. If the body absorbs these substances as quickly as possible, it can achieve the goal of quickly replenishing blood. Foods that are high in high-quality protein include milk, lean meat, eggs, soy products, etc. Foods that are high in iron include animal liver, jellyfish, shrimp, sesame, kelp, black fungus, seaweed, shiitake mushrooms, peas, jujube, longan, etc. Pork liver, kidney and beef are high in folic acid, and animal liver, pig or sheep kidney, fermented bean curd are rich in vitamin B12. In addition, you can use an iron pan when cooking.

Four blood-replenishing medicinal foods

1. Ginseng, jujube and pork liver soup

15-20 grams of Codonopsis pilosula, 20 jujubes, and 50-100 grams of pork liver. Wash Codonopsis pilosula and jujube, soak them in warm water for 30 minutes, then add appropriate amount of cold water, simmer for 30 minutes, filter out the juice, add appropriate amount of water and boil for 15 minutes to extract the juice. Mix the two juices together, cook with pork liver, season and eat.

2. Longan and Yam Soup

15 grams of longan meat, 30 grams of yam, and 100 grams of rice. Wash the rice and put it into the pot with longan meat and yam. Add appropriate amount of cold water and simmer until it is well cooked. Season and eat.

3. Pig Blood Soup

Rinse 500 grams of pig blood, add onion, ginger and a small amount of rice wine, stir-fry in a pan, add appropriate amount of water and boil until cooked, add a small amount of salt and MSG, and it is ready to eat.

4. Red Date Peanut Porridge

10 red dates, 50 grams of peanut kernels with skin, and 100 grams of rice, wash them and put them into the pot together, add appropriate amount of water, and simmer until well-cooked.

Five Tips for Donating Blood

If you have symptoms such as cold, fever, cough, etc. two days before donating blood, you should postpone donating blood; women should avoid donating blood during menstruation and the 3 days before and after. It takes about two to three weeks for the blood to fully recover after donating blood. Therefore, dietary adjustments should be maintained for at least half a month.