High Thoracic Epidural Anesthesia Does Not Inhibit Sympathetic Nerve Activity in the Lower Extremities 

Abstract

A high thoracic epidural anesthesia with adequate sensory blockade of upper thoracic dermatomes may be achieved without blockade of caudal parts of the sympathetic nervous system. This finding differs from that of earlier studies that used indirect methods to evaluate changes in sympathetic nerve activity.

Effects of thoracic epidural analgesia on lower urinary tract function in women

“…19 An intact sympathetic activity at level T12--L1 and stress-induced activation postoperatively and/or an inhibition of the parasympathetic activity could lead to a decrease in detrusor pressure. Interestingly, detrusor overactivity, present in three patients preoperatively, could not be identified during TEA.…”

A survey of postoperative epidural and intravenous analgesia in Greece

“…In addition, in all these 10 departments, a sympathetic blockade of the lower extremities was induced, which may contribute to adverse effects, but not to an improvement of the upper abdominal or thoracic analgesia. For thoracic or upper abdominal surgery, thoracic epidural analgesia provides better dynamic analgesia compared to lumbar [18], and also improves gastrointestinal, respiratory and cardiac function [19,20], and decreases the risk of hypotension, urinary retention and limb weakness [21][22][23].…”

Systemic, but not pulmonary, hemodynamics are depressed during combined high thoraco-cervical epidural and general anesthesia in dogs

“…Magnúsdóttir et al 11 have shown that high thoracic epidural anesthesia does not inhibit sympathetic nerve activity in the lower extremities. Low thoraco-lumbosacral sympathetic blockade causes visceral and lower limb vasodilatation with a large vascular capacity and the subsequent reduction of venous return, which may evoke tachycardia.…”

“…At a clinical dosage, sevoflurane depresses hemodynamics, [11][12][13] whereas hemodynamic depression of propofol is mild. 13,14 Therefore, hemodynamics during combined anesthesia may vary when different anesthetics are administered.…”