J Crew...
You are under local anesthetic when they perform the Stellate Ganglion Block. They have to sit you upright and they use a fluoroscopy guide, like an ultrasound, to see exactly where they need to insert the needle into your neck area.
The pain is very minimal...You wake up with a tiny bandaid like you just had a shot

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I would suggest getting in contact with your Dr. ASAP, because it sounds like yours is spreading quick like mine did. He should see you sooner. If he is an RSD specialist, he should understand.
Hope this helps!
Heather