The depth of burn determines the potential for successful wound healing and will therefore help guide the initial treatment regime. (11) Depending on the depth of tissue damage, burns are classified (10) as either;
- Superficial dermal partial thickness
- Mid dermal partial thickness
- Deep dermal partial thickness
- Full thickness.
Intermediate, or mid-dermal burn depth wounds are, by definition, difficult to assess in the first few days following injury, even experienced clinicians are only correct 67% of the time (10,12, 13). The evolving nature of the burn wound makes it essential to reassess these burn wounds at least within 48 hours, when exudate and oedema have settled, and sometimes repeatedly, in order to assess wound healing potential.
Speed of capillary refill is a good indicator of burn depth
The extent and speed of capillary refill is the most useful clinical method to assess burn depth. Bear in mind however the presence of capillary refill at the time of initial assessment does not mean that the burn will remain superficial. In practice, burn wound evolution frequently results in increased depth of burn injury tissue damage (9).
While it is relatively easy to diagnose superficial burns and severe deep burns, those of intermediate or mixed thickness are more problematic. Most burn wounds, especially those of larger areas, and flame burns, are not homogenous with respect to depth. They are usually a mixture of areas of different depths.