Conventions for the ICD-10-Cm Flashcards
The ICD-10-CM Tabular List contains categories, subcategories and codes. Characters for categories, subcategories and codes may be either a letter or a number. How many characters are in the category?
- A three-character category that has no further subdivision is equivalent to a code. Subcategories are either 4 or 5 characters. Codes may be 3, 4, 5, 6 or 7 characters. That is, each level of subdivision after a category is a subcategory. The final level of subdivision is a code. Codes that have applicable 7th characters are still referred to as codes, not subcategories. A code that has an applicable 7th character is considered invalid without the 7th character.
NEC
“Not elsewhere classifiable”
This abbreviation in the Alphabetic Index represents “other specified.” When a specific code is not available for a condition, the Alphabetic Index directs the coder to the “other specified” code in the Tabular List.
NOS
“Not otherwise specified”
This abbreviation is the equivalent of unspecified.
“Unspecified” codes
Codes titled “unspecified” are for use when the information in the medical record is insufficient to assign a more specific code. For those categories for which an unspecified code is not provided, the “other specified” code may represent both other and unspecified.
Excludes1
A type 1 Excludes note is a pure excludes note. It means “NOT CODED HERE!” An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
Excludes2
A type 2 Excludes note represents “Not included here.” An excludes2 note indicates that the condition excluded is not part of the condition represented by the code, but a patient may have both conditions at the same time. When an Excludes2 note appears under a code, it is acceptable to use both the code and the excluded code together, when appropriate.
“Code also” note
A “code also” note instructs that two codes may be required to fully describe a condition, but this note does not provide sequencing direction.
Signs and symptoms
Codes that describe symptoms and signs, as opposed to diagnoses, are acceptable for reporting purposes when a related definitive diagnosis has not been established (confirmed) by the provider. Chapter 18 of ICD-10-CM, Symptoms, Signs, and Abnormal Clinical and Laboratory Findings, Not Elsewhere Classified (codes R00.0 - R99) contains many, but not all, codes for symptoms.
Conditions that are an integral part of a disease process
Signs and symptoms that are associated routinely with a disease process should not be assigned as additional codes, unless otherwise instructed by the classification.
Conditions that are not an integral part of a disease process
Additional signs and symptoms that may not be associated routinely with a disease process should be coded when present
Acute and Chronic Conditions
If the same condition is described as both acute (subacute) and chronic, and separate subentries exist in the Alphabetic Index at the same indentation level, code both and sequence the acute (subacute) code first
Combination Code
A combination code is a single code used to classify:
Two diagnoses, or
A diagnosis with an associated secondary process (manifestation)
A diagnosis with an associated complication
Combination codes are identified by referring to subterm entries in the Alphabetic Index and by reading the inclusion and exclusion notes in the Tabular List.
Assign only the combination code when that code fully identifies the diagnostic conditions involved or when the Alphabetic Index so directs. Multiple coding should not be used when the classification provides a combination code that clearly identifies all of the elements documented in the diagnosis. When the combination code lacks necessary specificity in
describing the manifestation or complication, an additional code should be used as a secondary code.
Sequela (Late Effects)
A sequela is the residual effect (condition produced) after the acute phase of an illness or injury has terminated. There is no time limit on when a sequela code can be used. The residual may be apparent early, such as in cerebral infarction, or it may occur months or years later, such as that due to a previous injury.
Coding of sequela generally requires two codes sequenced in the following order: the condition or nature of the sequela is sequenced first. The sequela code is sequenced second.
Laterality
Some ICD-10-CM codes indicate laterality, specifying whether the condition occurs on the left, right or is bilateral. If no bilateral code is provided and the
condition is bilateral, assign separate codes for both the left and right side. If the side is not identified in the medical record, assign the code for the unspecified side.
Borderline Diagnosis
If the provider documents a “borderline” diagnosis at the time of discharge, the
diagnosis is coded as confirmed, unless the classification provides a specific
entry (e.g., borderline diabetes). If a borderline condition has a specific index
entry in ICD-10-CM, it should be coded as such. Since borderline conditions
are not uncertain diagnoses, no distinction is made between the care setting
(inpatient versus outpatient). Whenever the documentation is unclear
regarding a borderline condition, coders are encouraged to query for
clarification.
