Question: We saw a patient who presented for a COPD exacerbation and he went into acute respiratory failure. We reported the ARF code but our administrator says that’s not appropriate. Is that not meant to be a primary diagnosis? Codify Subscriber Answer: According to ICD-10 guidelines, if acute respiratory failure (ARF) is the primary reason for the patient’s visit, then you may choose an appropriate code from subcategory J96.0- (Acute respiratory failure…), or subcategory J96.2-, (Acute and chronic respiratory failure…) as the primary diagnosis. But if the ARF occurs later, the rules change. “Respiratory failure may be listed as a secondary diagnosis if it occurs after admission, or if it is present on admission, but does not meet the definition of principal diagnosis for hospital reporting guidelines,” the 2018 ICD-10-CM Official Guidelines for Coding And Reporting say. When ARF is coexistent with another acute condition, (such as myocardial infarction [I21.-, I22.-], cerebrovascular accident [I63.-], aspiration pneumonia J69.- [Pneumonitis due to solids and liquids…]), the selection of principal diagnosis will be different according to the situation. In this situation, selecting the correct code can be a little tricky, depending on whether the other existing pathology is respiratory or non-respiratory in nature, and also on the circumstances of admission. Here’s how to make your decision: