I had one sential node removed in November 2018 during a lumpectomy for stage 1A invasive ductual. The doctors told me no BP or blood draws in that arm which for me was the left arm. At my first follow up post treatments, they told me if 4 or fewer nodes removed , it's ok to use that arm. An hour later I saw my radiation oncologist and they said it's not ok. These doctors are all on the same team for my care and they are not on the same page about common procedures!
I'm going to stick with my right arm to be on the safe side. Why invite trouble when my right arm is normal and not compromised by surgery. So we will see when I have my next appointment.