Background and Objectives Selective sympathetic denervation during epidural anesthesia results in a small, active gut. These changes can also result in selective activity in one segment of the gut that is absent in other segments.

Case Report A 61-year-old male was scheduled for bilateral total knee replacement during epidural anesthesia. Following onset of the epidural block, he experienced severe left-sided chest pain. Surgery was canceled. A portable chest radiograph revealed a widened mediastinum, and he underwent angiography to rule out a dissecting thoracic aortic aneurysm. The left subclavian artery could not be visualized, and an MRI was obtained, which was normal. After his return to the intensive care unit, he had a large bowel movement and his chest pain resolved.

Conclusion Selective activity of the gastrointestinal tract during the onset of epidural anesthesia created a visceral pain, which effectively simulated pain with a cardiovascular origin.