One of the biggest changes in ICD-10-CM is the time frame for reporting an acute myocardial infarction (MI). In ICD-9-CM, an acute MI is one that is stated as such or for a documented duration of eight weeks or less and symptomatic.
ICD-10-CM shortens that to a four-week time frame, which could be confusing at first since the standard under ICD-9-CM has been an eight-week time frame.
ICD-10-CM includes some additional challenges for coders and clinical documentation improvement specialists. The American Hospital Association (AHA) addressed some of the gray areas in recent Coding Clinic guidance.
Of course, not all of the questions have been answered. Coders will likely find more gray areas as they continue to learn ICD-10-CM and when they actually begin using ICD-10-CM to code records.
For example, ICD-10-CM does not include a code for unspecified degenerative disc disease, says Nelly Leon-Chisen, RHIA, director of coding and classification for AHA in Chicago. ICD-10-CM also does not have a default code for degenerative disc disease.
ICD-10-CM breaks the condition down by the affected region:
- Cervical
- Thoracic
- Thoracolumbar
- Lumbar
- Lumbrosacral
If the physician does not specify the affected area, coders must query, Leon-Chisen says. However, a default code or new index entry could be coming when the Cooperating Parties release the first regular update to ICD-10-CM codes, currently scheduled for one year after implementation. The last regular update to ICD-10-CM was made in 2011, so many changes are expected.
The National Center for Health Statistics, one of the Cooperating Parties, is aware of the discrepancies in the index and has agreed to review and correct the index entries, Leon-Chisen says.
Neoplasms
In ICD-10-CM, coders will still assign codes based on the Neoplasm Table located in the front of the manual. The ICD-9-CM and ICD-10-CM Neoplasm Tables include the same categories for neoplasm type:
- Malignant primary
- Malignant secondary
- Ca in situ
- Benign
- Uncertain
- Unspecified behavior
Coders need to be careful not to confuse uncertain with unspecified, says Sarah A. Serling, CPC, CPC-H, CPC-I, CEMC, CCS-P, CCS, AHIMA-approved ICD-10-CM/PCS trainer for Precyse Solutions in Wayne, Pennsylvania.
A “neoplasm of uncertain behavior” is a specific pathologic diagnosis that is used for a lesion whose behavior cannot be predicted. The lesion is currently benign, but it may become malignant over time. Only report a code for uncertain behavior if the physician or pathologist documents that he or she is unsure whether the neoplasm is malignant or benign.
If the physician simply doesn’t specify, use unspecified. When in doubt about which code to use, query the physician.
Coders also need to remember that neoplasms are not always cancerous, Serling says. A neoplasm may be benign, so coders need to carefully read the documentation.
The terms primary and secondary may also confuse coders, Serling says. A primary malignancy is not always the principal diagnosis. Primary means this is the site where the malignancy started. Likewise, the term secondary refers to a metastatic malignancy. It is a neoplasm that has moved from one part of the body to a new site.
A secondary neoplasm may be the first-listed code or principal diagnosis when the patient is being seen for treatment of that neoplasm and not the primary neoplasm.
For example a female patient may have primary neoplasm of the upper inner quadrant of the left breast (C50.212). Her cancer may metastasize to her pelvic bone (C79.51). If she is being seen to treat the bone cancer, C79.51 would be the principal diagnosis.
Do not code “mass” or “lump” from the Neoplasm Table, Serling says. A "mass" is not considered a neoplastic growth. Report a code from to category D49 (neoplasms of unspecified morphology and behavior by site) when the physician documents the terms growth, new growth, neoplasm, or tumor.
External causes
The external cause codes in ICD-10-CM include a great deal of specificity, not only for how the injury occurred, but also for where the patient was and what he or she was doing. For example, if a patient is injured at home, coders can choose from the following place of occurrence codes:
- Y92.010, kitchen of single-family (private) house as the place of occurrence of the external cause
- Y92.011, dining room of single-family (private) house as the place of occurrence of the external cause
- Y92.012, bathroom of single-family (private) house as the place of occurrence of the external cause
- Y92.013, bedroom of single-family (private) house as the place of occurrence of the external cause
- Y92.014, private driveway to single-family (private) house as the place of occurrence of the external cause
- Y92.015, private garage of single-family (private) house as the place of occurrence of the external cause
- Y92.016, swimming-pool in single-family (private) house or garden as the place of occurrence of the external cause
- Y92.017, garden or yard in single-family (private) house as the place of occurrence of the external cause
- Y92.018, other place in single-family (private) house as the place of occurrence of the external cause
- Y92.019, unspecified place in single-family (private) house as the place of occurrence of the external cause
When the physician’s documentation includes this information, coders should use that information. However, physicians don’t always include this information in the record. The physician may only care that the patient was home, but not note which room or what type of dwelling the patient resides in. If the physician does not document the information, coders need to report an external cause code.
Coders may use documentation available from non-physicians, says Gretchen Young-Charles, RHIA, senior coding consultant for the AHA.
Coders can use an ED note, ambulance transcript, and nurse’s notes as long as the information is part of the official medical record, Young-Charles says. In cases where the physician and non-physician practitioner’s documentation on the external causes don’t agree, the physician wins, she adds.
Remember that not all payers require external cause codes on the claim form and no national standard exists for their use.
Email your questions to Senior Managing Editor Michelle A. Leppert, CPC, at mleppert@hcpro.com.