The effect of epidural morphine on human intestinal motility in the early postoperative period.

The early postoperative recovery of intestinal motility and the response of motility to epidural morphine were investigated in 20 patients. Periodic motor activities in the jejunum were recovered within 32 hours in all cases. The length of these cycles increased gradually from the 1st (23.2 min) to the 4th (41.7 min) postoperative day. Morphine and lignocaine were given through an epidural catheter. Morphine induced premature migrating motor complexes (MMC) in all cases, whereas lidocaine failed to evoke this response in every case. The mean duration (19.8 min) and maximal amplitude (62.8 mmHg) of the burst activities induced by morphine were significantly longer and higher than those occurring spontaneously (7.7 min and 35.6 mmHg, respectively). The intervals between the induced and the subsequent spontaneous contractions were the same as the intervals between spontaneous contractions. These observations indicate that epidural morphine induced premature MMC without interrupting recovery patterns from postoperative gastrointestinal paralysis.