Blister (nonthermal) of right index finger, sequela

This code signifies a non-heat-related blister located specifically on the right index finger, representing a long-term complication or residual effect of an initial injury or condition. The blister is no longer in its acute phase but persists as a sequela.

This code is appropriate when documenting a patient presenting with a chronic or residual blister on their right index finger that is not due to a burn or frostbite. It should be used when the original cause of the blister is no longer active, but the blister itself remains as a lasting consequence. Examples include blisters from chronic friction, pressure, or a resolved allergic reaction.

• Always ensure the blister is explicitly documented as being on the right index finger and is non-thermal in origin.
• The "S" seventh character indicates a sequela, meaning this code is used for complications or conditions arising as a direct result of a previous injury or disease.
• Code also the underlying cause of the original blister if it is still relevant and known, using an appropriate external cause code if applicable.