OVERVIEW
Alkalis include hydroxides of potassium, sodium, calcium, and magnesium, as well as sodium bicarbonate and fluorides. Because of their widespread use in industry, alkali burns are also more common in clinical practice. The common alkaline agents commonly used to cause injuries are caustic soda (sodium hydroxide, potassium hydroxide), lime and ammonia, etc. And strong alkali can dehydrate tissue cells and saponify fats. In addition, alkali ions combine with proteins to form soluble proteins that can penetrate into deep tissues. If early treatment is not timely, the wound can continue to expand or deepen and cause severe pain.
Etiology
Caused by contact with alkalis. Alkalis include hydroxides of potassium, sodium, calcium, and magnesium as well as sodium bicarbonate and fluoride. Alkalis absorb water from tissues, causing cellular dehydration and necrosis, as well as heat production to aggravate the injury, and they bind tissue proteins to produce basic denatured protein compounds. Alkaline denatured protein compounds are easy to dissolve, and can further act on normal tissue proteins, resulting in deeper development of the lesion; strong alkali can also saponify fats, and the heat generated by saponification can make the deeper tissues continue to ring death, so alkali burns are more serious than acid burns.
Symptoms
1. Strong alkali burn
Alkali burns, due to the alkali on the tissue of the water absorption effect, is the local cell dehydration, alkali ions and tissue protein to form alkali denaturation protein complex, and this complex is soluble and strong, can make alkali ions to further penetrate to the deep tissues, causing damage. Saponification of adipose tissue, the heat generated during saponification, can continue to damage the deep tissue and deepen the wound. Therefore, strong alkali burns are often clinically manifested as: the wound is sticky smooth or soap-like changes, scabs softer, with a tendency to progressive deepening, the depth is often in the depth of Ⅱ degree or more; severe pain; wound infection is easy to concur with traumatic sepsis.
2. Lime burns
Lime is calcium chloride, calcium hydroxide in water and release a lot of reaction heat, so it can cause alkali burns and thermal burns of the skin, aggravating each other. Burn wounds are dry, brown and painful. And there is often lime remaining on the wound.
3. Ammonia burns
Ammonia is one of the fertilizers commonly used in agriculture, highly volatile, irritating, dissolved in water to generate ammonium hydroxide. Ammonia commonly used concentration of 18% to 30%, is a medium-strength alkali, it is the same with the strong alkali type of lipolysis infiltration characteristics. Common clinical types are: ① ammonia contact skin or mucous membrane burns; ② ammonia or ammonia vapor caused by inhalation injury, the complications are inhalation injury of the lower respiratory tract and pulmonary edema, which should be taken seriously.
Examination
Same as thermal burns. If necessary, check whether it is accompanied by respiratory tract inhalation injury.
Diagnosis
Diagnostic points:
1. history of sodium hydroxide or potassium hydroxide exposure.
2. soft, wet scabs with reddened, blistered margins caused by burns with concentrated alkaline solutions. The scab does not prevent continued infiltration of the deeper tissues by the alkali. The pH paper test on the wound shows an alkaline reaction.
3. Respiratory tract injury may occur if alkali vapor is inhaled. Alkaline substances invade the eyes, can destroy the cornea, conjunctiva and even iris, resulting in serious injury or even blindness.
4. Except acid burns and other alkali burns.
Differential diagnosis
It is mainly differentiated from acid burns, radioactive burns and fire burns. The history of specific exposure to alkaline chemicals can be differentiated.
Treatment
Alkali burns should be immediately rinsed with a large amount of water and/or a weak acidic solution, the longer the rinsing time, the better the results, up to 10 hours or no slippery feeling is particularly good, but 2 hours after the injury to deal with the poor results. If the pH value of the wound reaches 7 or more, you can also use 0.5% to 5% acetic acid, 3% boric acid or 10% citric acid to neutralize the wet wound, and then rinse with water.
After the wound is rinsed clean, it is best to use exposure therapy in order to observe the changes in the wound. Deep burns should be cut and implanted as early as possible. If the first ammonia vapor inhalation injury should closely observe the patient’s lung condition, timely response to the possible complications of inhalation injury.
Questions you may be concerned about
What are the wrong ways to treat strong alkali burns?
Strong alkali burns treatment error methods are mostly neutralized with acidic solutions, for quicklime burns, direct water flushing should be avoided.
Strong bases are able to penetrate tissues and cause dissolution of tissue proteins, thus causing more damage to skin tissues than acids. When strong alkali burns occur, it should be careful not to use acidic solutions to neutralize, acid and alkali will meet the chemical reaction will produce a large amount of heat, resulting in an increase in the temperature of the burned area, aggravating the condition.
For quicklime burns, should avoid directly rinsing with water, water and quicklime will also have a chemical reaction to generate heat, resulting in a rise in local temperature, aggravating the condition of the burn.
For strong alkali burns, should immediately use a large amount of water to rinse, lime burns patients need to wipe the surface of the lime particles, and then give a large amount of water to rinse, remember not to be sent to the hospital without treatment.
The longer the strong alkali exists on the skin, the more serious the burns are, and after treatment with water, the patient should seek medical attention to clarify the extent of the burns, and give symptomatic treatment such as treatment of scabs, and if necessary, skin grafting may be required.