The extent of injury is best described using the percentage of the total body surface area (%TBSA) that is affected by a burn. The measurement of burn surface area is important during the initial management of people with burns for estimating fluid requirements and determining need for transfer to a burns service.
Erythema (superficial burn) should not be included when calculating burn area.
- With severe burn injuries (>50%TBSA) it maybe easier to calculate what isn’t burnt then subtract it from 100 to get %TBSA burns
- Use the Palmar method to calculate %TBSA for smaller burns. Always use the patients hand, not the clinicians.
- In the prehospital and emergency department setting, the %TBSA burns is more important than the depth of burn. %TBSA burns has indications for severity of injury, fluid resuscitation and transfer destination. Depth of burn becomes more significant after arrival at the Burn Service as depth of burn will determine how the Burn Service will manage it.
- If %TBSA burn estimation is inaccurate it has the potential to negatively impact fluid resuscitation by providing too much or too little fluid. Always titrate fluid resuscitation volumes according to resuscitation end points. Urine output is a simple and easy method to assess perfusion