Electrical Injury

Question 1

What are exit marks in electrical burns?

Answer 1

Exit marks in electrical burns are variable in appearance, often seen as splits in the skin at points where the skin has been raised into ridges by passage of the current. In high-voltage current, the exit often appears as a ‘blow-out’ type wound.

Example: In high-voltage burns, sparking may occur over many centimeters causing numerous individual and confluent areas of third-degree burns or red/brown punched-out spark lesions.

Question 2

What are flash or spark burns?

Answer 2

Flash or spark burns occur where the contact is less firm, allowing an air gap to exist between skin and conductor. The current jumps the gap as a spark, causing the outer skin keratin to melt over a small area. On cooling, the keratin fuses into a hard brownish nodule, usually raised above the surrounding surface, known as a ‘flash/spark burn’.

Question 3

What are Joule burns in electric burns?

Answer 3

Joule burns are specific and diagnostic marks of electric burns found at the point of entry. They are round, oval, or irregular, chalky white, shallow, centrally collapsed blisters with a raised border. The crater floor is lined by pale flattened skin, and the blister is created by the steam produced in the heating of tissues by the electric current, known as endogenous burns.

Example: Joule burns are commonly found on exposed parts of the body, especially on the palmar aspects of hands.