Iodine, alcohol, mercurochrome? Here's what you need to know about trauma!

Author: Chen Zhi, deputy chief physician of Beijing Emergency Center

Reviewer: Liu Zhi, Chief Physician, Xuanwu Hospital, Capital Medical University

In daily life, bumps and bruises are inevitable, and it is very necessary to know some first aid knowledge related to trauma.

1. How to correctly choose disinfectants for wounds to prevent infection?

Iodine tincture is a good skin disinfectant. It does not need to be deiodinated and can be left directly on the skin, which is very irritating to the skin. However, if you use iodine tincture, it also has a strong bactericidal ability. However, after applying it, you must use alcohol to remove the iodine in the iodine tincture, otherwise the iodine in the iodine tincture will cause great irritation to the skin.

Figure 1 Original copyright image, no permission to reprint

There are some other disinfectants, such as hydrogen peroxide, which is a very good disinfectant for purulent wounds and wounds with residual dirt. Because it will produce a lot of bubbles when applied to the wound, people may not accept it, but it is actually not a big problem.

The red and gentian violet used in the past are basically no longer used. This is because the antibacterial ability is very poor, especially for red mercury, which can cause other problems when applied to the skin. The most important component of red mercury is red mercury. If the skin wound is large, applying a large amount of red mercury may cause mercury poisoning in the human body.

One thing that is especially important to remember is that whether you are using iodine tincture or iodine tincture, they must not be mixed with mercurochrome. Otherwise, iodine and mercury will combine to form mercuric iodide, which will cause rapid poisoning in the human body, which is very dangerous.

Iodine tincture is suitable for disinfection of large-area wounds as well as small-area wounds. It has a wide range of applications and is effective against bacteria and most viruses. Alcohol, on the other hand, is only effective against some pathogenic bacteria and has no effect on viruses.

If the wound is very small, you can also wipe it with alcohol when there is no iodine. But we need to eliminate a misunderstanding about alcohol disinfection. Alcohol sterilization is dependent on what? It depends on the concentration of alcohol. Medical alcohol is 75%, which means that 75% concentration has the strongest destructive power on bacteria. Too high or too low concentration will not achieve the sterilization effect.

In daily life, we use some high-alcohol substances, such as those with a concentration of more than 90%, to wipe some special instruments. Industrial alcohol cannot be used for disinfection. Although its concentration is high, its actual bactericidal ability is poor.

Some people may ask, if there is no 75% alcohol, can we find a bottle of strong Erguotou liquor? Erguotou liquor is 52 degrees or 56 degrees, and some liquors are 66 degrees, but they do not reach the concentration of 75%, cannot destroy bacteria, and cannot achieve the effect of disinfection.

Therefore, the alcohol we usually drink cannot prevent wound infection. Currently, the recommended common disinfectant is iodine tincture.

2. What is the most effective method to stop bleeding after trauma?

The safest, most effective and most direct way to stop bleeding from a wound is to place a dressing larger than the edge of the wound on the surface of the wound and apply direct pressure to stop bleeding. There are several things to pay attention to during direct pressure to stop bleeding:

First, the dressing you choose must be appropriate, second, the time must be sufficient, and third, the bandage must be done properly.

Why is it best not to apply pressure directly with your hands? First, because your hands are dirty and can easily cause infection. Second, if you apply pressure directly on the wound surface, many gaps will be exposed, and sometimes it is impossible to apply pressure, and blood will flow out through the fingers. At the same time, after the hand is pressed on the surface of the wound, a blood scab will form. The hand cannot be pressed on the skin all the time. If the hand leaves, the blood scab will be broken, causing bleeding again.

So it is best to choose a gauze pad, or use a cleaner towel or handkerchief that is large enough to cover the surface area of ​​the wound.

Be careful not to use diapers or other highly absorbent materials to stop bleeding, because the dressing itself can absorb a lot of blood. Sometimes, on the surface, it seems that no blood has come out, but in fact, the blood has been absorbed by the gauze, which can easily cause hemorrhagic shock and is not conducive to stopping bleeding.

In addition, cover the surface of the wound with gauze and apply pressure to it with your hands. Especially when some small arteries are ruptured, the pressure will be very high, so you need to put your hands on it to maintain the pressure for a sufficient time.

How long should the pressure be applied? There is a coagulation mechanism after bleeding. When the blood has no power, it will stay there and coagulate into a blood clot. It usually takes four to twelve minutes. If it is a small artery or vein bleeding, it has a certain power to spray out, and the coagulation time is longer. Therefore, when applying pressure to stop bleeding, the pressure time should be at least ten to twenty minutes to form a relatively stable blood clot locally.

Figure 2 Original copyright image, no permission to reprint

Third, after applying pressure, the surface seems to have stopped bleeding. At this time, do not easily uncover the gauze, or the blood has not stopped oozing out of the gauze. Be careful not to tear it off. You can find some dressings to cover the gauze. If you uncover it, the newly formed blood scab will be torn again, which will aggravate the bleeding.

After the dressing is placed, we need to find some suitable bandages and towel rolls for pressure bandage and go to the hospital for treatment in time. Of course, we must pay attention to protection on the way to the hospital.