hi goblue. i had eight nb in my neck for my rsd in my wrist and was put to sleep for all of them at my request. i didn't have any spread from them but had moments of burning sensations at the site where the needle was put into my neck. but it didn't last too long. i'm not a dr and am just letting you know my experience but if i were you i would talk to you dr to make sure he knows your concerns. i hope that whatever you do you feel better soon. sending caring thoughts and hugs your way.
P.S. i have always had an anesthesiologist accompany my dr for every procedure and surgery i've had. and i make sure they all know i have rsd and to not touch the rsd site. i think its very important to have an anesthesiologist along with my drs. even my pm dr uses one. take care.