Assessing the depth of a burn
To make an accurate assessment of the depth of a burn, skin needs to be cleaned, blisters removed (except for small non-tense blisters [<6mm]) and capillary refill time tested.
Guidance on which blisters to de-roof and how to do it by the London and South East of England Burn Network (LSEBN) can be found here.
The depth of the burn can be classified into 1 of 4 types. The British Burn Association (BBA) accepted definition has replaced the older 1st, 2nd and 3rd degree classification.12
In summary, assessing the depth of a burn is necessary to determine what the patient needs immediately, and what they may require going forwards in their management.
The distinction between epidermal burns (erythema) and those that are deeper is necessary as epidermal burns are excluded from the %TBSA calculation when deciding on the need for resuscitation and fluid management.
The distinction between full thickness burns and anything more superficial is necessary as those with full thickness burns, depending on location, are at risk of ventilatory problems or limb ischaemia and may require urgent surgical intervention.
Learning bite
The distinction between different types of partial thickness burns is not clinically relevant to the emergency practitioner. Only the inclusion of full thickness, and exclusion of epidermal burns aids in management.