Two points:

1) US Core only enables an implantable device and needs to also allow reference to a non-implantable device (specifically DME but also to address software as a device). FHIR Device resource allows both.

2) US Core should provide guidance about how to reference placement, ordering and/or use of a device in a consistent manner: Suggested options to provide greater clarity for expressing device placement or usage include:

• Procedure for
• placement/insertion of a device, or
• use/manipulation of a device for which the result attribute can reference the expected outcome of such use.

• Observation allows reference to an observation about device usage, stability, and presence.
• Condition allows reference to the existence of an implantable device on a problem list.
• DeviceRequest  enables reference to an order for the device with the requester attribute indicating the source of the order information (e.g., requester is practitioner if ordered by the physician; the requester is patient / Care Partner if the patient or caregiver reports the device is in use, i.e., not initiated by a clinician order for durable medical equipment) - I.e., parallel to how an active medication list is managed in US Core.