Can I put this on my resume?

I worked as a med surg rn for a hospital. But floated to the ER numerous times, when needed. My duties there was to take on the care of the patients who were in the process of being stabilized and were to be admitted to medsurg. So in a nut shell, when a patient came to the emergency room, they were stabilized by the ER nurse. But obviously had other orders that needed to be executed immediately for that patient.

So when I floated to the ER, I took those patients in, max I took were 8 patients (YEA, I was loosing it but kept it together) they were slowly coming in, starting with 2, then 4 then 5 and so on.
The pace was so much faster too.

ANYWAY,

How can I add this on to my experience on my resume.
I wanted to have a separate subtitle for this extra skill I took on.
Any ideas please?

Thank you
When you write a description regarding your duties in you med-surg position, you could include that you also floated to the ED when needed, and give a brief description of your duties as a float.

What OCN said. You cannot list it as a separate job, but you can certainly get in there that you did this as part of the med-surg job at XYZ Hospital.