ICD 10 Coding Alert

Hint: Don’t get caught up on principal diagnosis.

The COVID-19-specific updates to the ICD-10-CM guidelines offer a lot of important information, but you’ll still need to rely on previously published guidelines to code some radiology scans accurately.

Work your way through each encounter to test your knowledge and skill.

Focus on Sequencing in This Tricky Scenario

Example: A patient with a positive COVID-19 diagnosis presents for a chest X-ray for an endotracheal tube (ET) placement. How should you sequence each respective ICD-10-CM code?

While the question is relatively straightforward, there’s a lot to consider when testing this example alongside the existing guidelines. Before diving into the order of the diagnoses, you’ve got to interpret the new ICD-10-CM guidelines as they pertain to COVID-19 coding. With respect to sequencing of codes, the guidelines state the following:

• “When COVID-19 meets the definition of principal diagnosis, code U07.1, COVID-19, should be sequenced first, followed by the appropriate codes for associated manifestations, except in the case of obstetrics patients as indicated in Section. I.C.15.s. for COVID-19 in pregnancy, childbirth, and the puerperium.”

To understand how you should sequence code U07.1 (COVID-19), you’ll want to home in on that first sentence that explains that COVID-19 should be sequenced first when it meets the definition of principal diagnosis. If you’re familiar with the ICD-10-CM guidelines as a whole, these instructions may cause some confusion as you continue to read into them. That’s due to of some of the phrasing included in this particular guideline; specifically, the “principal” diagnosis. According to Section II of the ICD-10-CM guidelines, the principal diagnosis is defined in the Uniform Hospital Discharge Data Set (UHDDS) as:

• “that condition established after study to be chiefly responsible for occasioning the admission of the patient to the hospital for care.”

Know This Difference in Context for These Terms

While you may frequently hear the terms first-listed and principal diagnosis used interchangeably, the former is technically designated for outpatient settings, while the latter is meant for inpatient coding. However, in Section I of the ICD-10-CM guidelines, you’ll encounter the term “principal diagnosis” often. When referenced in Section I, you should not refer back to the Section II guidelines on principal diagnoses. Rather you may consider the principal diagnosis and the first-listed diagnosis to be one in the same. “Despite Section II of the guidelines’ language surrounding principal diagnoses, guidance in Section I is appropriate for both principal diagnoses and first-listed diagnoses,” says Sheri Poe Bernard, CPC, of Poe Bernard Consulting in Salt Lake City.

Without this context, you might fall victim to the fallacy that the principal diagnosis guidelines apply to radiological services furnished for patients with a place of service (POS) of 21 (Inpatient Hospital). Nonfacility radiology coders working on imaging services for patients admitted to the hospital should still abide by the Section I, III, and IV guidelines. In other words, when the ICD-10-CM guidelines advise that you sequence U07.1 first when it meets the definition for principal diagnosis, what it really means is that U07.1 needs to meet the criteria for the principal reason for the visit. So, if a COVID-19 diagnosis is incidental, or secondary, to the reason for the visit, U07.1 will not be sequenced as the primary diagnosis.

Check With Provider for Crucial Background Info

Consider a scenario where a patient (inpatient or outpatient) presents for imaging for a COVID-19 pulmonary manifestation. In this example, you’ll still report U07.1 as the first-listed diagnosis and the manifestation as the secondary diagnosis. If the patient presents for imaging or treatment with a known incidental COVID-19 diagnosis, you should code the reason for the visit as the first-listed diagnosis, and U07.1 as a secondary diagnosis. Keep in mind, however, that a patient with a known positive COVID-19 diagnosis will not typically present for unrelated imaging or treatment until the diagnosis has resolved.

Looking back to the original example once again, it’s now clear that you’ll need additional information in order to know how to code it properly. While the POS is not going to influence the sequencing of the diagnosis codes, you’ve got to check with the provider to determine whether the intubation is being performed due to a COVID-19 pulmonary manifestation — or for an unrelated reason.

If the COVID-19 diagnosis is unrelated to the intubation, you’ll report the reason for the intubation as the first-listed diagnosis in addition to Z46.82 (Encounter for fitting and adjustment of non-vascular catheter) and U07.1 as a secondary diagnosis. If the provider does not elaborate on a clinical indication relating to the reason for the intubation, report Z46.82 as the first-listed diagnosis. If the addendum adds that the intubation is due to a conditioning relating to COVID-19, you’ll report U07.1 as the first-listed diagnosis, and Z46.82 and the manifestation code as secondary diagnoses.