Epidural anesthesia accelerates the recovery of postischemic bowel motility in the rat

Intestinal ischemia is associated with derangement of gastrointestinal motility. Uncontrolled clinical observations that bupivacaine injected into the epidural space causes faster recovery of bowel motility after various abdominal operations led us to assess the hypothesis that epidural anesthesia can hasten the recovery of gastrointestinal motility in the immediate postischemic period.

Gut motility studies were performed in rats in which epidural anesthesia and intestinal ischemia could be initiated without the need to provoke surgical trauma. Epidural lidocaine was compared to epidural saline in their effect on intestinal motility after a 30-min period of bowel ischemia.

Total ischemia to the small bowel resulted in pronounced postischemic adynamic ileus as evidenced by only 0.7% of the total length of the small bowel filled with a marker meal at the end of the study period (transit index) compared with 84.4% in the control group. Lidocaine epidural anesthesia caused significantly more rapid resolution of the adynamic ileus (60.3% of the bowel filled with the marker meal vs. 30.9% in the controls in which saline was injected).

Epidural lidocaine compared to epidural saline hastens the recovery of gastrointestinal motility in rats after a 30-min period of bowel ischemia. This effect may be elicited by attenuation of sympathetic efferent inhibitory pathways or by vasodilatation caused by the sympathetic block. These results suggest that lidocaine epidural block not only alleviates pain in situations of ischemic injury to the bowel but may also hasten the recovery from postischemic paralytic ileus.