Sympathetic Blocks: The Evidence

Abstract

The sympathetic nervous system has been implicated in numerous pain syndromes ranging from neuropathic pain to vascular pain to visceral pain. In light of this, sympathetic ganglia have been the target of local anesthetic blockade to determine the sympathetic role in the transmission of pain. If analgesia is afforded with local anesthetic blockade, chemical or thermal neurolysis have been utilized to attempt to provide long-term relief. Despite frequent use of minimally invasive sympathetic blocks and neurolysis by pain practitioners, their efficacy for providing analgesia has been sparsely reported in the literature. Many case reports and case series have been published, but few placebo-controlled, blinded studies exist. This manuscript will review the literature on sympathetic blocks and summarize existing studies for each of the sympathetic blocks. The goal is to provide past, current, and future pain physicians with evidence that they can use to provide appropriate care for their patients.

Multimodal Frequency Treatment for Facial Pain Caused by Chronic Rhinosinusitis: A Pilot Study

“…In a study by Ansari et al [53], 95% of patients with facial pain at the beginning of the study reported significant improvement after the study. The facial pain effect size observed in our study (d = 0.96) was much higher than that estimated from Young et al's data (d = 0.51), likely due to the application of multimodal frequencies (70)(71)(72)(73)(74)(75)(76)(77)(78)(79)(80) Hz and 1 MHz) in the AxioSonic system. Our effect size for quality of life measures using the SNOT-22 questionnaire (d = 0.45) was lower than Young et al's paper [40] (d = 0.9).…”

“…The SPG is involved in tissue inflammation, lacrimation, mucus production and other parasympathetic processes [71][72][73][74]. Low frequency neurostimulation (20 Hz, much lower than ultrasound frequencies) of the SPG or the Vidian nerve leads to vasodilation and associated inflammation [75,76].…”

Raquianestesia total após bloqueio de gânglio estrelado em paciente com síndrome dolorosa complexa regional: relato de caso

“…Second line drugs indicated for limited situations are steroids and other anticonvulsants and antidepressants. Sympathetic block is one of the commonest options 7 and more promising results are obtained the earlier the blockade is induced 8 . For upper limbs CRPS (UULL), stellate ganglion blockade is indicated 9 and is aimed at decreasing pain and functionally improving the affected limb.…”

Gender differences in the human cervicothoracic ganglia

“…Functionally, paravertebral ganglia are involved in many physiological and pathological aspects of neuropathic, vascular, visceral pain syndromes, the Raynaud's syndrome and hyperhydrosis. Several interventions on ganglia-surgical and chemical sympathectomy, the ganglion block, and chemical or thermal sympatholysis are applied as a possible treatment for pathological conditions [2]. The stellate ganglion block decreases the cerebral vascular tone for relieving cerebral vasospasm [4].…”