Say Goodbye to the O2 CMN

On September 27, 2021, the Centers for Medicare and Medicaid Services (CMS) added the following language to the Oxygen (O2) National Coverage Determination (NCD) via a “decision memo,” stating: The CMN requirement has been removed from the NCD. This conflicts with the currently active O2 Local Coverage Determination (LCD). However, the NCD unequivocally wins.

Does that mean you can stop getting O2 Certificates of Medical Necessity (CMNs)?

Unfortunately, it’s not as simple as it sounds. Current recommendations from leading consultants are that if a provider decides not to obtain CMNs, it should only apply this to new setups effective September 27, 2021, until the DME Medicare Administrative Contractors (MACs) post guidance and resolve certain discrepancies with the O2 LCD. In addition, this should only be done for “straight-forward” O2 orders, meaning orders with hypoxic test results (≤89% SAT or ≤59 mmHg ABG) and documented respiratory distress or difficulty breathing.

Continue to get CMNs or Hold claims where guidance is pending (i.e., acute conditions beyond 120 days, recertifications of rentals started before September 27, 2021, cluster headaches, and non-hypoxic test results). You will need to manually hold/release the claims/orders in your billing system if you choose not to pursue CMNs. Officially, the DME MACs have said not to change anything we’re doing until the LCD is revised.

Continue to bill with the KX modifier, which indicates a Standard Written Order (SWO) is on-file and the medical record supports the items as reasonable and necessary. Continue to use the CR modifier where appropriate, as well as a HA0 narrative “COVID-19” to all claims impacted by the public health emergency, which is still active.

Bottom Line: We’re currently in a transition period.

While it is true that the decision memo was published and is binding, the lack of guidance from the MACs puts it in a grey area. The DME MACs have said for providers not to change anything until they can issue guidance (i.e., continue getting CMNs signed). At this time, discontinuing the CMN is voluntary.

The safest bet is to continue getting CMNs signed until guidance is received. Providers can opt to not get a CMN on qualifying orders. However, to get the claims through the claims processing system, the CR modifier needs to be used with the “COVID-19” narrative.

[The information contained in this article does not constitute legal or regulatory advice. Please reference relevant provider manuals, NCDs, LCDs, etc. If you are unclear or seeking legal guidance, please contact your healthcare attorney.]


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