A burn is defined as an injury to the skin or other organic tissue caused by thermal trauma. It occurs when some or all of the cells in the skin or other tissues are destroyed by hot liquids (scalds), hot solids (contact burns), or flames (flame burns). Injuries to the skin or other organic tissues due to radiation, radioactivity, electricity, friction or contact with chemicals are also considered as burns
Chemical burn is caused by corrosive substances such as acids and alkalis. These chemicals are known to cause significant tissue damage when they come in contact with skin surface. A pH of 7 is neutral. Acids are lower in pH and alkalis are higher in pH. Litmus paper can be used to confirm the type of chemical.
Chemicals causing burn
1. Acids- Accidental or due to violence
2. Toilet cleaner
3. Sulphuric acid
4. Hydrochloric acid
5. Chemicals in the industries
• Most of the acids produce coagulation necrosis by denaturing proteins. It forms coagulum or eschar. This coagulum is thick leathery layer of dead skin.
• Alkalis though look mild, but produce more severe injury. They cause liquefaction of the tissue. This involves denaturation of proteins and saporification of fat. The effect of alkali remains ongoing and cause increasing depth of damage.
Depth and severity of burn depend upon
1. PH of the chemical
2. Concentration of the agent
3. Duration of the contact with the agent
4. Volume of the agent used
5. Physical form of the chemical agent
6. Involvement of the organ.
Mode of Injury
The effect of the chemicals depend upon the mode of chemical injury. The vitriolage or acid violence is deliberate throwing of acid on someone causing burn over face and upper part of the body. This is aimed at maiming or disfigure the women and children. Often the eyes are affected be cause of the direct contact of acid to the cornea and eye ball. The chemical injuries caused in the industries affect hands and lower part of the body. The chemicals in the industries may have irritant fumes, which cause respiratory burn. Ingestion of chemicals may cause burn of oral cavity, pharynx and esophagus.
The chemical burn is characterized by discoloration of skin with clear line of demarcation. It is brown or black with sulphuric acid and yellow with nitric acid. The trickle marks are the special features. There is absence of blisters. The chemical substance may be present over the surface and the clothing. The acid burn victim suffers from severe pain and burning. In case of acid attack, the corrosives may enter in the eyes and cause corneal damage. This causes severe pain in the affected eye.
Initial management of chemical burn:
• Removal of smeared clothes
• Removal of metallic ornaments in and around acid burn area.
• Manual removal of solid chemicals with no touch technique
• Removal or capping of source of chemical
• Irrigation with copious plain water for 15 – 20 minutes
• Do not try to neutralize the chemical as it may cause exothermic reaction and more damage.
• The rescuer must be careful not to cause harm himself/herself.
• The water should not spill over rest of the normal body parts especially eyes, nose, mouth and ears.
• Many chemical may cause inhalation injury due to toxic chemical vapours. The source of chemical should be capped or removed from the scene.
Management in the hospital:
1. Copious washing to continue till litmus test is negative.
2. Chemical inhalation burn should be assessed and managed.
3. Treatment of burn area is management of any other burn injury. One has the choice of early surgical excision or conservative therapy.
4. Early excision is preferred for early and better recovery.
5. These burns heal with bad scars and deformities of face and neck
6. These may require secondary surgeries for correction of deformities.
7. Psychological support at every stage of management is essential part of treatment.
8. Finally rehabilitate to get back to society.