Estimate burn depth

The contemporary approach to describing burns focuses on the anatomical depth of the burn wound rather than using traditional degrees (e.g., first degree, second degree). Burn depth is classified as epidermal, dermal, or full thickness.

Burns can be classified into five categories based on depth:

  1. Epidermal: Only the outer layer of the skin (epidermis) is affected. These burns typically heal without scarring.
  2. Superficial Dermal Partial Thickness: Damage extends into the superficial layer of the dermis. These burns are painful and usually heal within 7-14 days with minimal scarring.
  3. Mid Dermal Partial Thickness: Damage penetrates deeper into the dermis. These burns often require longer healing times and may result in scarring.
  4. Deep Dermal Partial Thickness: More extensive damage to the dermis, with potential involvement of hair follicles and sweat glands. Healing may require weeks to months and scarring is common.
  5. Full Thickness: Damage extends through the entire thickness of the skin, often involving underlying tissue, muscles, or bones. These burns typically require surgical intervention and may result in significant scarring and functional impairment.

Methods of Assessment

There are three key aspects to remember when assessing burn depth.

Speed of capillary refill

The speed of capillary refill is the most useful clinical examination to indicate burn depth. However, it's important to note that initial assessment findings may not accurately reflect the final depth of the burn.

Capillary return in superficial dermal burns

Test and re-test

This is important for mid-dermal Assessing intermediate or mid-dermal burns can be challenging even for experienced clinicians, particularly in the first few days following injury.

The evolving nature of burn wounds necessitates reassessment, ideally within 48 hours and sometimes repeatedly, to accurately gauge wound healing potential once exudate and oedema have settled. Most burn wounds, particularly larger or flame burns, are usually a mixture of areas of different types of depths.

Mid to deep dermal burns

Speed of assessment

The optimal time to assess burn depth is typically 3-5 days post-burn. This allows for the Zone of Stasis to manifest whether it will deteriorate into part of the Zone of Coagulation or recover. Distinguishing between different depths of dermal burns can be difficult clinically. While technologies like non-contact Laser Doppler Imaging (LDI) are available to aid in determining burn depth, they are considered adjuncts to clinical assessment. Repeated serial clinical assessment by experienced burn clinicians remains the standard method for determining burn depth.

Complete your burns assessment

Burn depth and % TBSA are both required for a complete burn assessment. If you have determined the burn depth, be sure to also calculate % TBSA of the burn.

Estimate burn area