Map which Chapter 8 bases apply, then show the need is daily and can be met only in a SNF (the practical-matter test). This is what a coverage reviewer looks for on a Part A day.
Observation & assessment; covered skilled procedure
Epistaxis management, post-operative packing/nares care, and device-related nares care are skilled services under Chapter 8, and significant epistaxis or a post-surgical nasal course carries a reasonable potential for a bleeding, airway, or CSF complication that requires daily nursing judgment.