Assessment
of burn depth
Burn depth depends, in thermal injury, upon:
• the temperature of the burning agent;
• the mode of transmission of heat;
• the duration of the contact.
Much of this information can be obtained from taking a good history of
the injury. Clinical examination of the burn wound may also show characteristic
features.
Skin
anatomy
The epidermis is the most superficial layer of the skin and provides the
waterproofing layer. It is constantly replaced from the basal layer. The dermis
is the thicker underlying area that supplies the strength and integrity of the
skin. It has a rich blood supply from the subdermal capillary network. It
contains the adnexal structures — hair follicles, sebaceous glands and sweat
glands. These adnexal structures contain epithelial cells that can proliferate
and heal a partial-thickness wound by epithelialisatton.
Superficial
burns
These have the ability to heal themselves by epithelialisation alone.
Epidermal burns look red, are painful, blisters are not present, and they heal
rapidly without sequelae. Superficial dermal burns are blistered and painful;
they should heal by epithelialisation within 14 days without scarring, but sometimes
leave long-term pigmentation changes.
Deep
burns
These have lost all adnexal structures and if left can only heal by
second intention with scarring. Deep dermal burns may be
In
practice most burns contain areas of differing burn depth. Decision making is
easy where burns are obviously superficial or obviously deep, with difficulties
arising in the distinction between the deeper superficial burns and deep dermal
burns.