Blister (nonthermal) of left hand, sequela

This code signifies a non-thermal blister located on the left hand that is a long-term effect or complication of a previous injury or condition. This indicates that the blister is not due to a recent burn or frostbite, but rather a persistent issue stemming from an earlier event.

Apply this code when documenting a patient presenting with a blister on their left hand that is a residual effect of a past injury, such as a prolonged pressure injury, friction, or a resolved allergic reaction. This is appropriate for follow-up encounters where the blister is no longer acute but a chronic manifestation.

• Always assign this code as a secondary diagnosis, following the code for the original injury or condition that caused the sequela.
• Ensure documentation clearly states the blister is on the left hand and is a sequela (e.g., "chronic blister from old friction injury").
• Do not use for acute blisters or blisters due to current thermal causes (burns, frostbite).