It is defined as a wound in which necrosis of wound occurs.
There are various types of burns:
1.Ordinary Burns- this is caused by dry heat, or flame, hot metal, etc.
2.Scald- this is caused by moist heat like steam or hot liquid.
3.Electric Burns- this is caused by high voltage electric current. This type of burn causes more damage to deep tissues and organs than skin.
4.Chemical Burns- this is caused by strong acid like sulphuric burn or base like ammonia that come in contact with skin or other tissues.
5.Radiation Burns- this is caused by excessive exposure to irradiations like X- rays or radium.
6.Cold Burns- this is caused by exposure to cold. This includes frostbite, chilblains, and trench foot.

Burns are classified in three grades:
1.First Degree Burns- these are superficial burns involved only epidermis. These are characterized itself by redness and swelling of affected part.
2.Second Degree Burn- in this whole epidermis gets destroyed. This is representing itself by formation of blisters.
3.Third Degree Burns- in this complete irreversible destruction of epidermis and dermis of skin is occurred. Because of destruction of blood vessels and nerves, these types of burns are usually painless.

Importance to know the extent of burns:
It is measured as a percentage of total body area affected. This can be estimated with the help of ‘RULE OF NINE’.

Head, Face and Neck                                                                                    9%
Right Upper Extremity                                                                                 9%
Left upper Extremity                                                                                     9%
Right Lower Extremity (thigh 9%, leg and foot 9%)                               18%
Left Lower Extremity (thigh 9%, leg and foot 9%)                                  18%
Anterior Trunk (chest 9%, abdomen 9%)                                                 18%
Posterior Trunk (upper half 9% and lower half 9%)                               18%
External Genitalia                                                                                           1%

This rule is applicable to adults only. In infants and children the surface area of head, face and neck is more than 9%.

Location of burn:
If the affected area is
1.Head, neck, face, nose and mouth- Airways could be obstructed resulting in breathlessness.
2.Extremities- Destruction of blood vessels may result in impaired healing.
3.Chest- Adequate movement is not possible due to scar formation resulting in impaired breathing process,
4.Flexors Area- Impaired movement due to scar formation. Example- palmar surface, area behind knee joints, groins, etc.

The affected area must be sterilized immediately. In cases of deep burns formation of crust will help in preventing infection. Those persons who are malnourished or suffering from anaemia, immuno-compromised diseases and systemic diseases like diabetes mellitus are more to infection than others.

In cases of mild first degree burn cases, proper first aid is required in the assistance of a specialist.
In cases of severe cases with complications like shock, hospitalization is required to support the patient health.

General Treatment:
1.Removal of crust in cases of third degree full thickness burns as it may compresses the adjacent blood vessels leading to cyanosis, paraesthesia, and etc. Sometimes, this crust present on the chest wall may impair breathing due to restricted movement of it so it become necessary to remove them.
2.Tetanus Prophylaxis- it must be given to a patient having burn injury.
3.Nutritional support.
4.Treatment of other complaints of patient like GIT disturbances.
Local Treatment:
1.First- Aid- The patient should be removed from source of heat. Cold water must be applied on the affected area for atleast 5 mins. Avoid excessive exposure to cold water as it may lead to hypothermia.
2.Burn- wound care- It should be cleaned properly and any antimicrobial agent must be applied topically.
3.Skin Grafting.
4.Physical Therapy and Rehabilitation.

Treatment of Shock:
1.Sedation- in order to palliate pain.
2.Fluid Resuscitation and Blood transfusion.
3.Maintenance of airways.