A burn is a type of injury to skin, or other tissues, caused by heat, cold, electricity, chemicals, friction, or radiation. Burns that affect only the superficial skin layers are known as superficial or first-degree burns. When the damage extends to deeper layers, they are classified as partial-thickness (second-degree) or full-thickness (third-degree) burns.

Immediate first aid

• airway, breathing, circulation
• burns caused by heat: remove the person from the source. Within 20 minutes of the injury irrigate the burn with cool (not iced) water for between 10 and 30 minutes. Cover the burn using cling film, layered, rather than wrapped around a limb
• electrical burns: switch off power supply, remove the person from the source
• chemical burns: brush any powder off then irrigate with water. Attempts to neutralise the chemical are not recommended

Assessment

Assessing the extent of the burn:

• Wallace's Rule of Nines: head + neck = 9%, each arm = 9%, each anterior part of leg = 9%, each posterior part of leg = 9%, anterior chest = 9%, posterior chest = 9%, anterior abdomen = 9%, posterior abdomen = 9%
• Lund and Browder chart: the most accurate method
• the palmar surface is roughly equivalent to 1% of total body surface area (TBSA). Not accurate for burns > 15% TBSA

Assessing the depth of the burn:

• The main differentiating feature between the level of dermal burns is the blanching erythema - blanching = superficial dermal

Investigations

• Examination of burn depth and extent