The effect of intraoperative thoracic epidural anesthesia and postoperative analgesia on bowel function after colorectal surgery: a prospective, randomized trial.

PURPOSE: Colorectal surgery is associated with postoperative ileus, which contributes to delayed discharge. This study was designed to investigate the effect of thoracic epidural anesthesia and analgesia on gastrointestinal function after colorectal surgery under standardized controlled postoperative care.

METHODS: Forty-two patients diagnosed with either colonic cancer, diverticulitis, polyps, or adenoma, and scheduled for elective colorectal surgery, were randomly assigned to either postoperative patient-controlled analgesia (PCA) with intravenous morphine (n = 21) or epidural analgesia with a mixture of bupivacaine and fentanyl (n = 21). Postoperative early oral feeding and assistance to mobilization were offered to all patients. Pain visual analog scale (1-100 mm), passage of flatus and bowel movements, length of hospital stay, and readiness for discharge were recorded.

RESULTS: Pain visual analog scale (visual analog scale, 1-100 mm) at rest, on coughing, and daily on mobilization was significantly lower in the epidural group compared with the patient-controlled analgesia group. Median values for the visual analog scale group were 7 (95 percent confidence interval, 2-18) mm, 19 (95 percent confidence interval, 4-38) mm, and 10 (95 percent confidence interval, 5-33) mm, respectively, and, for the patient-controlled analgesia group, were 24 (95 percent confidence interval, 18-51) mm, 59 (95 percent confidence interval, 33-74) mm, and 40 (95 percent confidence interval, 29-79) mm, respectively (P < 0.01). Intake of protein and calories and time out of bed were similar in both groups. Mean time intervals +/- standard deviation from surgery to first flatus and first bowel movement occurred earlier in the epidural group, 1.9 +/- 0.6 days and 3.1 +/- 1.7 days, respectively, compared with patient-controlled analgesia, 3.6 +/- 1.5 days and 4.6 +/- 1.6 days, respectively (P < 0.01). Postoperative complications occurred in 33 percent of the patient-controlled analgesia group and 28 percent of the epidural group. There was no significant difference in length of hospital stay between the two groups with a mean of 7.3 +/- 3.7 days in the patient-controlled analgesia group and 8.5 +/- 4.2 days in the epidural group. Readiness for discharge was similar in both groups.

CONCLUSION: Thoracic epidural analgesia has distinct advantages over patient-controlled analgesia morphine in providing superior quality of analgesia and shortening the duration of postoperative ileus. However, discharge home was not faster, indicating that other perioperative factors influence the length of hospital stay.