Autonomic Nerve Blockade

Sensory nerves from deep visceral and somatic organs travel with sympathetic nerves of the autonomic nervous system (also see Chapter 1 for more detail about autonomic nerve anatomy). The ability to block sympathetic nerves at key points can help to reduce pain of deep somatic and visceral origin. In addition, some of these sensory inputs along the sympathetic pathways may establish reflex arcs capable of sending impulses back to deep visceral and somatic organs. These reflex arcs can exacerbate pain on aggravation or activation by pain fiber input. Blocking certain key relay centers along the sympathetic nervous system can break down such painful reflex arcs, resulting in relief from deep visceral and somatic pain cycles.