Changes in Human Plasma Catecholamine Concentrations during Epidural Anesthesia Depend on the Level of Block

The current study was designed to test the hypothesis that increasing levels of sensory analgesia will produce progressive decreases in circulating catecholamines. We used plasma concentrations of E (epinephrine) and NE (norepinephrine) as an indirect measure of the effect of epidural anesthesia on the sympathetic nervous system