Sympathetic Nerve Blocks
Sympathetic nerve blocks are performed for sympathetically mediated pain. It’s a complicated type of pain to explain, but an easier way to think about it is that sometimes chronic pain is influenced by hormones in the body. The hormones responsible for increased chronic pain are epinephrine and norepinephrine. Sympathetic nerve blocks temporarily reduce these hormones in the area of pain, which can result in pain relief, sometimes long-term pain relief, particularly when the procedure is repeated.
Common situations in which sympathetic blocks are performed include complex regional pain syndrome, painful peripheral neuropathy, phantom limb pain, angina, peripheral vascular disease, Raynaud’s phenomenon, excessive sweating, post-herpetic neuralgia, abdominal pain, intestinal pain, pelvic pain, rectal pain, tailbone pain, and cancer pain. Specifically, the most common sympathetic nerve blocks are the stellate ganglion, splanchnic nerve, celiac plexus, lumbar sympathetic, hypogastric plexus, and ganglion impar blocks.
Usually, a combination of a steroid and numbing medication is injected using x-ray or ultrasound guidance to make sure the injection is in the correct area. Certain physical signs may be seen with proper placement of the medication, including increased temperature and skin color changes. If the patient obtains a certain percentage of relief, then the pain generator has most likely been correctly identified. Radiofrequency procedures may be performed for potentially longer-lasting effects.