ICD-10-CM coding guidelines: A season for change

September 28th, 2020 / By Karla VonEschen, CPC, CPMA

Each year around mid-September, I can see and feel the changes happening.  The air gets cooler, the leaves begin to turn beautiful colors, and ICD-10-CM diagnosis changes become effective. It almost makes sense that the diagnosis code changes coincide with the change in season. By now, most of us have either received our new code books or have seen information on code changes effective October 1. For me, identifying the code changes seems straightforward, but identifying what has changed in the coding guidelines always seems to be a challenge. After all, ICD-10-CM guidelines clearly state, “Adherence to these guidelines when assigning ICD-10-CM diagnosis codes is required under the Health Insurance Portability and Accountability Act (HIPAA).” The guideline updates for 2021 are heavily focused on COVID-19, and for good reason. Below are some of the notable changes for 2021.  It is vital coders read through the new guidelines and note what will be most impactful for their organization. 

Guideline Changes

  • The 2021 guidelines now include language indicating patients may self-report social determinants of health. This impacts code families Z55 (Problems related to education and literacy) and Z65 (Problems related to other psychosocial circumstances). In order to code when patients self-report, physicians must document the information and note that it was communicated by the patient as part of the medical record and sign off. If your organization is reporting social determinant codes, it may be beneficial to perform an audit and review charts after October 1 to identify any gaps in documentation.

Chapter Specific Guidelines

  • Chapter 1: A new section has been added for coronavirus infections, so it will be important for coders to read and understand the guidance changes. Coders will need to continue to educate physicians to include “positive” or “confirmed” language when documenting for COVID-19. Simply documenting “COVID-19” is not enough to code U07.1. There are new guidelines for respiratory and non-respirator manifestations when a patient is COVID positive. Physicians must document “due to,” “with,” or “in” as part of the documentation to show linkage between COVID-19 and the manifestation.

  • Chapter 2: There are new guidelines for coding insulin and non-insulin drugs for patients who are diabetic. This new language expands on guidance for patients who use insulin and oral hypoglycemic drugs. Codes Z74.9 and Z79.899 are to be appended when patients use insulin and an injectable non-insulin antidiabetic drug and physicians have documented for both drugs in the patient note. When documentation indicates use of oral hypoglycemic drugs and an injectable non-insulin antidiabetic drug, append codes Z79.84 and Z79.899.

  • Chapter 10: There is a new section for coding vaping related illnesses. Take note that codes for associated respiratory signs and symptoms due to vaping should not be coded with a definitive diagnosis code. This is great education for coders if your organization currently treats illnesses from vaping. There are circumstances when it is appropriate to add additional codes such as for gastrointestinal symptoms, when present and documented by the physician. 

  • Chapter 15: A new section, 15.s, includes instruction for encounters when COVID-19 is the reason for the encounter along with sequencing guidelines. Physicians must indicate if the patient is COVID-19 “positive” or “confirmed” for diagnosis code U07.1.  Refer back to chapter 1 for COVID-19 related guidelines.

  • Chapter 16: There is new guidance instructing coders to append U07.1 as a first listed code when a newborn has tested positive for COVID-19. If the newborn contracted COVID-19 in utero or during the birthing process, code P35.8 is assigned for other congenital viruses followed by U07.1. Physicians will need education to clearly state the newborn is COVID-19 positive and how the infection was contracted for appropriate coding. If the type of transmission is not specified, U07.1 is appended. Remember that from a data reporting perspective and to appropriately identify trends, physicians need to be as specific as possible documenting diagnoses. 

  • Chapter 21: The most noteworthy guideline change applies to observation code Z03.818. For FY2021, the guidelines note that although “observation codes are primarily to be used as a principal/first-listed diagnosis,” that “An observation code may be assigned as a secondary diagnosis code when the patient is being observed for a condition that is ruled out and is unrelated to the principal/first-listed diagnosis.” Previously, the guidelines had indicated observation codes should be primary or first listed only with some exception language. Organizations that use these observation codes will want to educate coders about the new changes. 

  • Chapter 22: This is a brand-new ICD-10 chapter for special purposes, codes U00-U85. For now, this chapter contains just two codes for vaping related disorders and COVID-19. Note that the guidelines for vaping related illness instruct coders not to code associated respirator signs and symptoms due to vaping when a definitive diagnosis has been documented by the physician. Use of additional codes for any other manifestations, such as acute respiratory failure, requires appropriate physician documentation. When documenting conditions that have a causal relationship, verbiage must be present to connect the two conditions, such as “with,” “secondary to,” “due to,” or “associated with” to apply the appropriate code.

Take some time to become familiar with the changes, especially as they relate to your individual organization. Now might also be a good time to identify codes that are changing and determine what the impact will be to your physicians. Pulling notes and performing a documentation review to identify deficiencies and then educating your physician staff will go a long way to ensure correct statistical data, appropriate financial planning, clinical preparedness and appropriate reimbursement for the health care organization.

Karla VonEschen is a coding analyst at 3M Health Information Systems.

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Center for Disease Control ICD-10-CM Codes