There is some confusion regarding the seventh character in medical coding including what it is and when to use it. The first important item to note is the difference between CPT and ICD-10 codes. CPT codes are used to report the service or procedure that was performed. ICD-10 codes are used to report diagnoses to support medical necessity. The seventh character is used in ICD-10 or diagnosis coding.
The seventh character is required when reporting accidents, injuries, fracture care, and poisonings. The three most common seventh characters are A, D, and S. Each is examined in more detail below:
A – Initial Encounter: The seventh character A is sued for the initial encounter of active treatment which may or may not include the first visit. Some examples of when to use A as a seventh character is surgical treatment, emergency department encounter, and evaluation and continuing treatment by the same or different physician.
D – Subsequent Encounter: The seventh character D is used for encounters after the patient has received active treatment and is now receiving routine care either during the healing or recovery phrase. Some examples of subsequent encounters include cast change or removal, an X-ray to check the healing status of a fracture, removal of fixation device, medication adjustment, or follow up visits following treatment of an injury.
S – Sequela: The seventh character S is used when there is a residual effect produced by the condition after the acute phase of the illness or injury has ended. There is no time limit on when a sequela code can be used as the residual effect may be apparent early or may take months or years to present itself. Examples of sequela include scar formation resulting from a burn, deviated septum due to a nasal fracture, and infertility due to tubal occlusion from old tuberculosis. When coding sequela, generally the condition or nature of the sequela is sequenced first. The sequela code is sequenced second.
Note: There is an exception to the sequela guidelines above. In instances where the code for sequela is followed by a manifestation code (identified in the tabular list and title) or when the sequela code has been expanded at the fourth, fifth, or sixth character levels to include manifestation(s). The code for the acute phrase of an illness or injury that led to sequela is never used with a code for the late effect or condition.