The needle, catheter, and probe used during this RFA procedure does not enter the spinal
canal and cannot cause those symptoms. In
the lumbar area, the anatomy is such that major blood vessels are not disturbed.
I am suspecting the local anesthetic absorbed by capillary action, or IV anesthesia used during your procedure may have caused these side effects -- perhaps the benzodiazepene medication midazolam (Versed) given as part of the "conscious sedation" used for this procedure.