what to do with new cardiac rythm changes

It depends on what kind of rhythm change. Your actions could range from immediate transfer to ICU or PCU and preparing for ACLS protocol (V-tach) to shrugging your shoulders and carrying on with your day (1st degree AVB).

I would recommend that on a med/surg unit you get a 12-lead EKG to confirm the rhythm and then call the doc to get further orders. If your hospital has a rapid response team, I would call them as well.

Patients can be asymptomatic and have a serious rhythm problem -- even with V-tach, patients can be assymptomatic for a while. A patient in A-Fib, while appearing asymptomatic, can be at high risk for complications such as CVA if they are left untreated. Any of the minor heart blocks can be an indicator for a major block to occur eventually.