New ICD-10-CM Coding Guideline Updates for Fiscal Year 2022: Part 2

Information regarding coding, coverage, and payment is provided as a service to our readers. Every effort has been made to ensure information accuracy.  However, HMP Communications and the authors do not represent, guarantee, or warranty that coding, coverage, and payment information is error-free and/or that payment will be received. The ultimate responsibility for verifying information accuracy lies with the reader.  

To our readers: As discussed in Part 1 of this series, Part 2 is dedicated to changes to the ICD-10-CM coding guidelines that wound care professionals should be aware of.  The new guidelines are effective from 10/1/2021–9/30/2022. The full text of the guideline is available here on the National Center for Health Statistics website. 

Implementation of these guidelines is a joint effort between the healthcare provider and the coder. It is essential to achieve complete and accurate documentation, code assignment, and reporting of diagnoses and procedures with this collaborative effort. The importance of consistent, complete documentation in the medical record cannot be overemphasized. Without such documentation accurate coding cannot be achieved. The entire record should be reviewed to determine the specific reason for the encounter and the conditions treated.

If a definitive diagnosis has not been established by the end of the encounter, it is appropriate to report codes for sign(s) and/or symptom(s) in lieu of a definitive diagnosis. When sufficient clinical information isn’t known or available about a particular health condition to assign a more specific code, it is acceptable to report the appropriate “unspecified” code (e.g., a diagnosis of pneumonia has been determined, but not the specific type). Unspecified codes should be reported when they are the codes that most accurately reflect what is known about the patient’s condition at the time of that encounter. It would be inappropriate to select a specific code that is not supported by the medical record documentation or conduct medically unnecessary diagnostic testing to determine a more specific code.

I have taken excerpts and quotes from the guidelines and included in this article the ones that can be most applicable to wound care for your convenience. At some point it is important to read the guidelines in their entirety for areas in which you work.

Laterality

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.

When a patient has a bilateral condition and each side is treated during separate encounters, assign the "bilateral" code (as the condition still exists on both sides), including for the encounter to treat the first side.

For the second encounter for treatment after one side has previously been treated and the condition no longer exists on that side, assign the appropriate unilateral code for the side where the condition still exists (e.g., cataract surgery performed on each eye in separate encounters).

The bilateral code would not be assigned for the subsequent encounter, as the patient no longer has the condition in the previously treated site. If the treatment on the first side did not completely resolve the condition, then the bilateral code would still be appropriate.

When laterality is not documented by the patient’s provider, code assignment for the affected side may be based on medical record documentation from other clinicians. If there is conflicting medical record documentation regarding the affected side, the patient’s attending provider should be queried for clarification. Codes for “unspecified” side should rarely be used, such as when the documentation in the record is insufficient to determine the affected side and it is not possible to obtain clarification.

Example: Patient has an ulcer on the plantar surface of the right foot. The patient also has a left foot ulcer on the heel and has a vascular ulcer of the right calf. When coding and billing for wound care it is important to match the diagnosis for which treatment is rendered during the encounter. So, if you do a debridement excising muscle tissue from the right lower extremity, which wound had tissue removed? The only way to match a procedure to a diagnosis code is by site and laterality. Think about this for a minute. If it is not easy for your coders to get this information, how do you think the payers will do with it? A coder and a payer need to be able to link up the story of each individual wound/ulcer diagnosis code with any treatments to a particular wound. I have seen charts with 10 wounds and cannot identify what treatments went with what ulcer/wound. The specific diagnosis codes will tell the story of each wound and their related treatments.   

I cannot stress how important it is to make sure that the documentation in the record treats each wound as unique. Why? Because if there are 10 total wounds and 2 treatments, without the appropriate diagnosis code how can you tell which ones received the treatment. This is especially important for ongoing care of the same ulcers over long periods of time.                                                                                                                                                                

Documentation by Clinicians Other Than the Patient's Provider

Code assignment is based on the documentation by the patient's provider (i.e., physician or other qualified healthcare practitioner legally accountable for establishing the patient's diagnosis). There are a few exceptions when code assignment may be based on medical record documentation from clinicians who are not the patient’s provider (i.e., physician or other qualified healthcare practitioner legally accountable for establishing the patient’s diagnosis). In this context, “clinicians” other than the patient’s provider refer to healthcare professionals permitted, based on regulatory or accreditation requirements or internal hospital policies, to document in a patient’s official medical record. These exceptions include codes for:

• Body mass index (BMI)
• Depth of non-pressure chronic ulcers
• Pressure ulcer stage
• Coma scale
• NIH stroke scale (NIHSS)
• Social determinants of health (SDOH)
• Laterality
• Blood alcohol level

This information is typically, or may be, documented by other clinicians involved in the care of the patient (e.g., a dietitian often documents the BMI, a nurse often documents the pressure ulcer stages, and an emergency medical technician often documents the coma scale). However, the associated diagnosis (such as overweight, obesity, acute stroke, pressure ulcer, or a condition classifiable to category F10, Alcohol related disorders) must be documented by the patient’s provider. If there is conflicting medical record documentation, either from the same clinician or different clinicians, the patient’s attending provider should be queried for clarification. The BMI, coma scale, NIHSS, blood alcohol level codes and codes for social determinants of health should only be reported as secondary diagnoses.

Documentation of Complications of Care

Code assignment is based on the provider’s documentation of the causal relationship between the condition and the care or procedure, unless otherwise instructed by the classification. The guideline extends to any complications of care, regardless of the chapter the code is located in. It is important to note that not all conditions that occur during or following medical care or surgery are classified as complications. There must be a cause-and-effect relationship between the care provided and the condition, and an indication in the documentation that it is a complication. Query the provider for clarification if the complication is not clearly documented.

As stated in the introductory section of these official coding guidelines, a joint effort between the healthcare provider and the coder is essential to achieve complete and accurate documentation, code assignment, and reporting of diagnoses and procedures. The importance of consistent, complete documentation in the medical record cannot be overemphasized. Without such documentation accurate coding cannot be achieved. The entire record should be reviewed to determine the specific reason for the encounter and the conditions treated.

If a definitive diagnosis has not been established by the end of the encounter, it is appropriate to report codes for sign(s) and/or symptom(s) in lieu of a definitive diagnosis. When sufficient clinical information isn’t known or available about a particular health condition to assign a more specific code, it is acceptable to report the appropriate “unspecified” code (e.g., a diagnosis of pneumonia has been determined, but not the specific type). Unspecified codes should be reported when they are the codes that most accurately reflect what is known about the patient’s condition at the time of that encounter. It would be inappropriate to select a specific code that is not supported by the medical record documentation or conduct medically unnecessary diagnostic testing to determine a more specific code.

Use of Z Codes

Z codes (other reasons for health care encounters) may be assigned as appropriate to further explain the reasons for presenting for health care services, including transfers between health care facilities, or provide additional information relevant to a patient encounter. The ICD-10-CM Official Guidelines for Coding and Reporting identify which codes may be assigned as principal or first-listed diagnosis only, secondary diagnosis only, or principal/first-listed or secondary (depending on the circumstances).

Possible applicable Z codes include:

Z59.0-, Homelessness
Z59.1, Inadequate housing
Z59.5, Extreme poverty
Z75.1, Person awaiting admission to adequate facility elsewhere
Z75.3, Unavailability and inaccessibility of health-care facilities
Z75.4, Unavailability and inaccessibility of other helping agencies
Z76.2, Encounter for health supervision and care of other healthy infant and child
Z99.12, Encounter for respirator [ventilator] dependence during power failure

The external cause of morbidity codes and the Z codes listed above are not an all-inclusive list. Other codes may be applicable to the encounter based upon the documentation. Assign as many codes as necessary to fully explain each healthcare encounter. Since patient history information may be very limited, use any available documentation to assign the appropriate external cause of morbidity and Z codes.

Personal History of COVID-19

For patients with a history of COVID-19, assign code Z86.16, Personal history of COVID-19.

Diabetes mellitus and the use of insulin, oral hypoglycemics, and injectable non-insulin drugs

If the documentation in a medical record does not indicate the type of diabetes but does indicate that the patient uses insulin, code E11-, Type 2 diabetes mellitus, should be assigned. Additional code(s) should be assigned from category Z79 to identify the Long-term (current) use of insulin, oral hypoglycemic drugs, or injectable non-insulin antidiabetic, as follows:
If the patient is treated with both oral medications and insulin, both code Z79.4, Long term (current) use of insulin, and code Z79.84, Long term (current) use of oral hypoglycemic drugs, should be assigned.

If the patient is treated with both insulin and an injectable non-insulin antidiabetic drug, assign codes Z79.4, Long term (current) use of insulin, and Z79.899, Other long term (current) drug therapy. If the patient is treated with both oral hypoglycemic drugs and an injectable non-insulin antidiabetic drug, assign codes Z79.84, Long term (current) use of oral hypoglycemic drugs, and Z79.899, Other long term (current) drug therapy. Code Z79.4 should not be assigned if insulin is given temporarily to bring a type 2 patient’s blood sugar under control during an encounter.

Pressure Ulcers

There is a new instruction for coding unstageable ulcers. If during an encounter, the stage of an unstageable pressure ulcer is revealed after debridement, assign only the code for the stage revealed following debridement. You do not code both the unstageable ulcer and the stage after debridement. Since I receive many questions regarding this topic I have included the current 2022 ICD-10-CM Guidelines for Pressure ulcers below:

Pressure ulcer stage codes

1. Pressure ulcer stages
Codes in category L89, Pressure ulcer, identify the site and stage of the pressure ulcer.

The ICD-10-CM classifies pressure ulcer stages based on severity, which is designated by stages 1–4, deep tissue pressure injury, unspecified stage, and unstageable. Assign as many codes from category L89 as needed to identify all the pressure ulcers the patient has, if applicable.

See Section I.B.14 for pressure ulcer stage documentation by clinicians other than patient's provider.

2. Unstageable pressure ulcers
Assignment of the code for Unstageable pressure ulcer (L89.--0) should be based on the clinical documentation. These codes are used for pressure ulcers whose stage cannot be clinically determined (e.g., the ulcer is covered by eschar or has been treated with a skin or muscle graft). This code should not be confused with the codes for unspecified stage (L89.--9). When there is no documentation regarding the stage of the pressure ulcer, assign the appropriate code for unspecified stage (L89.-- 9). If during an encounter, the stage of an unstageable pressure ulcer is revealed after debridement, assign only the code for the stage revealed following debridement.

3. Documented pressure ulcer stage
Assignment of the pressure ulcer stage code should be guided by clinical documentation of the stage or documentation of the terms found in the Alphabetic Index. For clinical terms describing the stage that are not found in the Alphabetic Index, and there is no documentation of the stage, the provider should be queried.

4. Patients admitted with pressure ulcers documented as healed
No code is assigned if the documentation states that the pressure ulcer is completely healed at the time of admission.

5. Pressure ulcers documented as healing
Pressure ulcers described as healing should be assigned the appropriate pressure ulcer stage code based on the documentation in the medical record. If the documentation does not provide information about the stage of the healing pressure ulcer, assign the appropriate code for unspecified stage.

If the documentation is unclear as to whether the patient has a current (new) pressure ulcer or if the patient is being treated for a healing pressure ulcer, query the provider.

For ulcers that were present on admission but healed at the time of discharge, assign the code for the site and stage of the pressure ulcer at the time of admission.

6. Patient admitted with pressure ulcer evolving into another stage during the admission
If a patient is admitted to an inpatient hospital with a pressure ulcer at one stage and it progresses to a higher stage, 2 separate codes should be assigned: 1 code for the site and stage of the ulcer on admission and a second code for the same ulcer site and the highest stage reported during the stay.

7. Pressure-induced deep tissue damage
For pressure-induced deep tissue damage or deep tissue pressure injury, assign only the appropriate code for Pressure-induced deep tissue damage (L89.--6).

Social Determinants of Health Codes

Describing social determinants of health (SDOH) should be assigned when this information is documented. For social determinants of health, such as information found in categories Z55-Z65, Persons with potential health hazards related to socioeconomic and psychosocial circumstances, code assignment may be based on medical record documentation from clinicians involved in the care of the patient who are not the patient’s provider since this information represents social information, rather than medical diagnoses. For example, coding professionals may utilize documentation of social information from social workers, community health workers, case managers, or nurses, if their documentation is included in the official medical record.

In Conclusion

Please take the time to review these guidelines as they may be a bit different than what you were used to. Staff meetings or other forums are usually a good way to discuss these to ensure consistency throughout the documentation. Don’t forget that Social Determinants of Health codes can be used to describe a patient’s specific issue that may be contributory to the decision to perform the treatment that is ultimately decided by the provider.

Donna Cartwright is senior director of health policy and reimbursement at Integra LifeSciences Corp., Plainsboro, NJ. She is approved as an AHIMA-approved ICD-10-CM/PCS trainer, and she has been designated as a fellow of the American Health Information Management Association.

Click here to download a PDF of this article.