Blister (nonthermal) of left back wall of thorax, sequela

This code signifies a non-thermal blister located on the left posterior thoracic wall, indicating a healed or residual effect of a previous injury or condition. The "sequela" designation means the blister is a late effect, not an acute or current injury.

Use this code when documenting a patient presenting with a blister on the left back of the chest that is a chronic or residual finding, such as from a resolved skin condition, pressure injury, or prior trauma. It is appropriate when the original cause of the blister is no longer active but its lasting effect is present.

• Always sequence this code after the code for the original condition or injury that caused the blister, if known and still relevant.
• Ensure the documentation clearly specifies "left back wall of thorax" and confirms the non-thermal nature and sequela status.
• Do not use for acute blisters; this code is specifically for late effects.