ICD-10-CM Coding Guidelines Series: Section 1.B. General Coding Guidelines

ICD-10-CM Coding Guidelines Series: Section 1.B. General Coding Guidelines

Posted by Stephani Scott
Jan 30, 2019 12:33:20 PM

This section is jam packed with guidelines for ICD-10-CM. These guidelines can be found throughout all chapter sections of the code book. For this blog, I will touch only a few of these guidelines.

First, coding signs and symptoms seems straight forward, however determining when a symptom vs. the definitive diagnosis or both should be coded can challenge any coder who is not well versed in these guidelines. The guidelines state; “Codes that describe symptoms and signs, as opposed to diagnoses are acceptable for reporting purposes when a related definitive diagnosis has not been established or confirmed by a provider. Signs and symptoms that are associated routinely with a disease process should not be assigned as additional codes unless otherwise instructed by the classification. Signs and symptoms that may not be associated routinely with a disease process should be coded when present.” It’s this last guideline that tends to be a challenge. Signs and symptoms that are not routinely associated with the definitive diagnosis should be reported as additional codes. For example, a child who presents with nausea and vomiting resulting in a diagnosis of gastroenteritis, should not have the codes nausea and vomiting assigned because these symptoms are routinely associated with the disease process. However, if the patient also has a headache, because this symptom is not routinely associated with gastroenteritis it would be appropriate to report the additional code for headache. Coders must have an understanding of disease processes to accurately code. If in doubt I suggest using the internet to research the disease and/or discuss the scenario with a physician.

A guideline that is often overlooked is the proper use of combination codes. A combination code is one in which two diagnoses are combined into one code or when a diagnosis is associated with a manifestation or complication. Coders often forget about the new combination codes in ICD-10-CM or simply overlook the rules outlined in the codebook. Combination codes can be identified by reviewing the subterm entries in the Alphabetical Index and by reading the inclusion and exclusions notes in the Tabular List. The first quarter 2016 issue of AHA Coding Clinic published a clarification stating the subterm “with” in the index should be interrupted as a link between primary condition and any other condition indented under the word “with”. Examples of combination codes include:

  • K35.32 - Appendicitis with perforation
  • E10.42 – Type I Diabetes with polyneuropathy
  • I25.110 – atherosclerotic heart disease of native coronary artery with unstable angina pectoris

The final guideline I wanted to discuss in ICD-10-CM is the term Sequelae which replaced the well-known and understood term Late Effect. The sequela concept is applied to codes as the 7th character digit S. Sequelae are residual effects, complications or conditions produced after the acute phase of an illness or injury has ended. There is not a specific time limit on when a sequela code can be used which can cause a debate among coders. A residual effect, complication or condition can present during the early stages of a disease processes such as with a cerebral infarction or it can occur months or years later. Examples of residual effects, complications or conditions include: scar due to a burn or other open injury, deviated septum due to a fractured nose, infertility due to a tubal occlusion, pain from an internal fixation device due to a fracture. The ICD-10-CM guideline instructs a coder to include two codes; first code the condition of nature of the sequela then code the sequela (the residual effect, complication or condition). An exception to this rule is when the code for the sequela (the residual effect, complication or condition) is followed by a manifestation code identified in the Tabular List. Additionally, the code for the acute phase of the illness or injury that led to the sequela (the residual effect, complication or condition) should never be used with the late effect code. For example, a patient with dysphasia following a nontraumatic subarachnoid hemorrhage should be coded with I69.021.

In all three of these guidelines a coder must not only know the rules but must understand disease processes and when to apply the rules appropriately. With the industry moving towards a risk based and valued based payment models it is ever more important to ensure accuracy of your coding.

Questions or Comments?