acid-base burns
Introduction
Introduction to acid and alkali burns Acids and alkali burns (burnsduetoacidsandalkalies) are most commonly found in sulfuric acid, hydrochloric acid, and nitric acid. In addition, acetic acid (glacial acetic acid), hydrofluoric acid, perchloric acid, and chromic acid are corrosive poisons. In addition to skin burns, the respiratory tract inhalation of volatile gases and mists of these acids (such as sulfuric acid mist, chromic acid mist) can also cause severe irritation of the upper respiratory tract. In severe cases, chemical bronchitis, pneumonia and pulmonary edema can occur. Alkali burns are more common in ammonia, sodium hydroxide, potassium hydroxide, and lime. The most common is ammonia burn, because it is extremely volatile, often with upper respiratory tract burns, and severe pulmonary edema. When a small amount of diluted ammonia is splashed on the eyes, it is prone to erosion and slow recovery. basic knowledge The proportion of illness: 0.001% Susceptible people: no special people Mode of infection: non-infectious Complications: nasal septum ulcer
Cause
Acid-base burn cause
(1) Causes of the disease
Common strong acids are nitric acid, sulfuric acid, hydrochloric acid, hydrofluoric acid, formic acid, phenol, etc., strong acid is corrosive, acts on the skin to absorb tissue moisture, dehydration of tissue, protein coagulation and necrosis, strong alkaline compounds have sodium, potassium, calcium , ammonium, hydrazine, etc. hydroxide.
(two) pathogenesis
The alkaline substance can dissolve the tissue, denature the tissue protein, saponify the fat, destroy the structure of the cell membrane, cause the lesion to develop in depth, produce dissolved necrosis, and penetrate and destroy deeply. The skin mucosal reaction caused by the two is primary. Caused by the stimulating effect, the severity of acid-base burn is related to the acidity and alkalinity, concentration, contact time and skin condition.
Prevention
Acid and alkali burn prevention
Before the operation, it can be coated with protective agent, wear protective equipment, and observe the safe operation rules during operation. It strives to keep the production process sealed and pipelined. The working place should be equipped with standing water source and necessary neutralizing agent.
Complication
Acid-base burn complications Complications, nasal septum ulcer
Contact with alkali powder or steam can cause irritation of the upper respiratory tract mucosa, occasionally cause nasal septum ulcer, perforation, eye can be photophobic, tearing, blurred vision and foreign body sensation, conjunctival congestion, redness, if splashed into concentrated alkali, especially It is sodium hydroxide, which can cause corneal damage and even blindness.
Symptom
Acid-base burn symptoms Common symptoms Secondary infections severe pain, severe pain, itching, papules, eczema, dry skin and edema
Acid burn
The symptoms of chemical burn caused by nitric acid, sulfuric acid and hydrochloric acid are basically the same. The skin lesions are mostly localized, the contact time is short, and the contact concentration is low. Only the contact part has flushing, itching, and dissipates quickly after disengagement; The contact concentration is large, the skin is red, swollen and burning, and then the brownish red swelling, blistering, and even ulceration, necrosis, and scarring after the treatment; long-term exposure to dilute sulfuric acid or hydrochloric acid can cause dry skin, keratinization, and easy to form cleft palate; Long-term exposure to acid mist can cause skin and mucous membrane irritation, and it can also cause eczema-like dermatitis changes, which can cause nasal septum perforation or pharyngeal mucosal ulcer, tooth erosion, ulcerative stomatitis or digestive tract inflammation, due to work Caution, it can also cause eye burns. The burn caused by hydrochloric acid is not as deep as that caused by sulfuric acid and nitric acid, and it is easy to form blisters. Nitric acid is a strong oxidant, which can cause yellow staining and deep burns, resulting in brown eschar. It becomes a deep ulcer that is difficult to heal. The sulfuric acid has a deep transdermal effect. It feels pain immediately after contact. The local skin turns white and then turns black, forming necrosis, and the surrounding is red and swollen. Eschar formation state clearly off the deep ulcers, heal very slowly.
Hydrofluoric acid (ie 40% aqueous hydrogen fluoride solution) begins to act slowly, so it is easy to be neglected and delay treatment. Lighter only has erythema, severe pain, whitening of skin at the contact site, edema, tissue coagulative necrosis, surface can start Bullae, blister wall tension, ulceration after breaking, if there is a small amount of hydrofluoric acid residue, continue to penetrate deep and around, necrotic tissue can extend deep into bone.
Phenol (carbolic acid) has the toxicity of puree. It has systemic and local effects. It can cause cell protein coagulation and can reach deep into human tissues. It will turn white immediately after exposure to high concentration of phenol. It will cause localization after brief numbness. Redness, bullae and necrosis, a large amount of phenol can be absorbed by the body can cause kidney damage, and phenol is easily neutralized by 65% ethanol or isopropanol.
7% of formic acid (antacid) can cause skin burns, and the skin mucous membrane is severely painful when burned with concentrated acetic acid, and forms a dirty gray-white necrotic tissue block.
2. Alkali burns
Sodium, potassium, calcium, ammonium, barium, etc. are strong alkaline compounds. Long-term exposure to low concentrations can cause dry skin, thinning of the deck, loss of luster, exposure to moderate concentrations, contact with local pruritus, acute dermatitis , may appear erythema, swelling, papules, blisters, erosion, such as improper treatment, can be converted to chronic dermatitis in a long time, contact with high concentration in contact with local conscious burning, burns, necrosis, deep ulcers, easy secondary infection, Healing is very slow and scars are left behind.
Examine
Acid-base burn inspection
The severity of the burn depends on the extent and depth of the injured tissue. The depth of burn can be divided into I, II, III and IV degrees.
I degree burn injury is the lightest. Burns the skin redness, pain, obvious tenderness, exudation or edema. Partially whitened when the injured area was lightly pressed, but no blisters.
The second degree burn injury is deep. Skin blisters. The bottom of the blisters is red or white and is filled with clear, viscous liquid. Sensitive to tenderness, whitening when oppressed.
A third degree burn is a full-thickness burn of the skin. The burned surface can be white, soft or black, charred leather. Since the burnt skin becomes pale, it is often mistaken for normal skin in white-skinned people, but it does not change color when pressed. Destroyed red blood cells can cause burnt local skin to be bright red, occasionally blisters, and the hair in the burned area is easily pulled out and feels diminished. The III degree burn area generally has no pain. Because the nerve endings of the skin are destroyed.
IV degree burn refers to the damage of subcutaneous tissues such as muscles and bones, etc., also known as destructive burns. It occurs mostly at the extremities, ears, nose and other parts. The main causes are flame burns, electric shocks, hot crushing and strong acid and alkali burns. The repair is difficult and the recovery time is long.
Diagnosis
Diagnosis and identification of acid and alkali burns
The clinical manifestations caused by this disease are similar to those of burns, so it is clinically necessary to distinguish from substantial burns and other chemical materials. According to the patient's clinical history and contact history, the chemical damage usually has a clear history of exposure to chemical raw materials, while the burns have the same symptoms, but the pathogenesis is different, usually there are blisters, skin scars, and clear The history of high temperature exposure.
