Epidural catheter-induced paresthesia accompanied by changes in skin color and temperature in an obstetric patient

Placement of epidural catheters for labor analgesia is a common procedure that has become more popular in recent years. However, this procedure can often cause paresthesia, which is typically characterized as a transient and intense burning pain radiating to the hip or leg. In this case report, we describe a patient who had persistent paresthesia in her right foot caused by an indwelling epidural catheter, which was successfully relieved following a partial withdrawal of the epidural catheter. More interestingly, we also observed dramatic changes in skin color and temperature (cold and pale) on her right foot that was well correlated both in time and location with the epidural-induced paresthesia. This cold and pale skin on the right foot represents a localized sympathetic discharge associated with the epidural-induced paresthesia, a phenomenon that has not previously been described. Based on the location of the paresthesia and the pathway of the sympathetic nerve fibers, it is unlikely that this localized sympathetic discharge was due to a direct irritation of the preganglionic sympathetic fibers in the spinal nerve roots by the epidural catheter and thus, a spinal reflex was probably involved. This phenomenon provided us with additional clinical evidence of nerve root irritation, which prompted us to act quickly, and resulted in a favorable outcome.