Inhibitory Effects of Dexmedetomidine and Propofol on Gastrointestinal Tract Motility Involving Impaired Enteric Glia Ca2+ Response in Mice.

Propofol and dexmedetomidine are popular used for sedation in ICU, however, inadequate attention has been paid to their effect on gastrointestinal tract (GIT) motility. Present study aimed to compare the effect of propofol and dexmedetomidine on GIT motility at parallel level of sedation and explore the possible mechanism. Male C57BL/6 mice (8-10 weeks) were randomly divided into control, propofol and dexmedetomidine group. After intraperitoneal injection of propofol or dexmedetomidine, comparable sedative level was confirmed by sedative score, physiological parameters and electroencephalogram (EEG). Different segments of GIT motility in vivo (gastric emptying, small intestine transit, distal colon bead expulsion, stool weight and number of fecal pellets, gastrointestinal transit and whole gut transit time) and colonic migrating motor complexes (CMMCs) pattern in vitro were evaluated. The Ca2+ response of primary enteric glia was examined under the treatment of propofol or dexmedetomidine. There is little difference in physiological parameters and composite permutation entropy index (CPEI) between administration of 50 mg/kg propofol and 40 µg/kg dexmedetomidine, indicated that parallel level of sedation was reached. Data showed that propofol and dexmedetomidine had significantly inhibitory effect on GIT motility while dexmedetomidine was stronger. Also, the amplitude (ΔF/F0) of Ca2+ response in primary enteric glia was attenuated after treated with the sedatives while the effect of dexmedetomidine was greater than propofol. These findings demonstrated that dexmedetomidine caused stronger inhibitory effects on GIT motility in sedative mice, which may involve impaired Ca2+ response in enteric glia. Hence, dexmedetomidine should be carefully applied especially for potential GIT dysmotility patient.

Effects of Epidural Co-administration of Morphine and Naloxone on Intestinal Motility after Total Hysterectomy / 대한마취과학회지

BACKGROUND: Epidural morphine is usually associated with decreased bowel motility and increased transit time. Low doses of intravenous naloxone have been known to reduce morphine-induced side effects including intestinal hypomotility without reversing analgesia, but the effect of epidural naloxone has not been defined in human study. Therefore we evaluated bowel motility and analgesia when naloxone was administered via epidural route. METHODS: Forty-two patients having epiduro-general analgesia for total hysterectomy were randomly assigned to one of two study groups. As a means of postoperative pain control, all received 1.5 mg of epidural morphine bolusly 1 hour before the end of surgery, and a continuous epidural infusion was started using a two-day infusor containing 2.5 mg of morphine in 0.125% bupivacaine 100 ml with either no naloxone (control group, n = 20) or 5 microgram/kg/day of naloxone (experimental group, n = 22). We measured the time to the postoperative first passage of flatus and feces to evaluate the restoration of bowel function, and visual analog scales (VAS) for pain during rest and movement. Scores were taken at 2 and 4 hours after the operation, 7 AM, 1 PM, and 7 PM of the 1st postoperative day and 7 AM and 1 PM of the 2nd postoperative day. RESULTS: The experimental group revealed less time to the first postoperative passage of flatus and feces. No significant difference was found in resting and movement VAS between the two groups. CONCLUSIONS: This study suggests that epidural naloxone reduces epidural morphine-induced intestinal hypomotility without reversing analgesic effects.

The Effect of Epidural Lidocaine Infused with Morphine on Pain and Bowel Motility after Hysterectomy / 대한마취과학회지

BACKGROUND: Postoperative ileus is considered to be caused by the activation of spinal reflexes originating from the abdominal cavity with the sympathetic nerves as the efferent nerves. Epidural anesthesia as a perioperative adjunct has been shown to provide superior pain control, and has been implicated in more rapid postoperative ileus resolution possibly through a sympathetic block mechanism. This study was undertaken to compare the effects of epidural morphine-lidocaine with those of epidural morphine alone on postoperative bowel motility and pain. METHODS: Forty-four ASA I or II women scheduled for transabdominal hysterectomy were considered for the study. They were randomly allocated to one of two groups. Group M (n = 22) received postoperative epidural morphine 16 mg by infusion pump, 2 ml/h, for 2 days, group ML (n = 22) received morphine 16 mg plus 0.42% lidocaine by infusion pump, 2 ml/h, for 2 days. Both group received morphine 4 mg in 0.5% lidocaine 8 ml epidurally as a single bolus when the peritoneum was closed. Postoperative pain, and the time interval from termination of operation to the first passage of flatus were checked RESULTS: In group ML, the times for first passing of flatus (33.4 +/- 10.5 h; mean +/- SD) and visual analogue scale score (0.3 +/- 0.6) were significantly shorter and lower than in group M (flatus 42.6 +/- 8.4 h and VAS score 1.3 +/- 1.7). CONCLUSIONS: The epidural lidocaine infused with morphine demonstrated earlier recovery of bowel motility and better postoperative pain relief than the epidural morphine alone.

Effects of Postoperative Patient-Controlled Ketorolac Analgesia on Recovery of Gastro-intestinal Motility after Gynecologic Surgery / 대한마취과학회지

BACKGROUND: Postoperative ileus remains a common condition that prolongs hospitalization and increases the cost of surgical therapy. Ketorolac, a potent nonsteriodal antiinflammatory drug, has been known to prevent small bowel ileus in a rodent model. Therefore, we compared the effect of intravenous patient-controlled analgesia (iv PCA) with or without ketorolac. METHODS: Fifty-four patients undergoing gynecologic surgery were assigned in a double-blind manner into one of three groups (n = 18). Pain control was achieved using meperidine 600 mg only (group M), meperidine 300 mg-ketorolac 150 mg (group MK) or butorphanol 10 mg-ketorolac 150 mg (group BK) during the 48 hours following surgery. It was designed as loading (30 mg), continuous infusion (9.6 mg/hr), PCA dose (9.6 mg) and lockout interval (15 min) for group M and as loading (30 mg of ketorolac), continuous infusion (2 ml/hr), PCA dose (2 ml), and lockout interval (15 min) for groups MK and BK. We measured the interval to the first flatus during the 72 hours following surgery and recorded the numerical rating score (NRS) of pain with side effects at 1, 6, 12, 24 and 48 hrs postoperatively. RESULTS: Ketorolac expedited the return of bowel function significantly (P < 0.05). Analgesic efficacy and side effect were not significantly different in all three groups. CONCLUSIONS: IV PCA with meperidine-ketorolac and butorphanol-ketorolac afforded equal analgesia compared to the meperidine only. It also allowed earlier recovery of bowel function in patients undergoing gynecologic surgery.

Effects of Epidural Naloxone on Intestinal Hypomotility Caused by Epidural Morphine after Gastrectomy / 대한마취과학회지

BACKGROUND: Epidural morphine is usually associated with decreased bowel motility and increased transit time. Low doses of intravenous naloxone have been known to reduce morphine-induced side effects including intestinal hypomotility without reversing analgesia, but the effect of epidural naloxone has not been defined in any human study. Therefore, we evaluated bowel motility and analgesia when naloxone was administered via the epidural route. METHODS: Forty patients having epiduro-general analgesia for subtotal gastrectomy were randomly assigned to one of two study groups. As a means of postoperative pain control, all received 1.5 mg of epidural morphine bolusly 1 hour before the end of surgery, and a continuous epidural infusion was started using a two-day infusor containing 2.5 mg of morphine in 0.125% bupivacaine 100 ml with either no naloxone (control group, n=20) or 5 microgram/kg/day of naloxone (experimental group, n=20). We measured the time to the first postoperative passage of flatus and feces to evaluate the restoration of bowel function, and visual analog scales (VAS) for pain, during rest and movement. Scores were taken at 2 and 4 hours after the operation, 7 AM, 1 PM, and 7 PM of the 1st postoperative day and 7 AM and 1 PM of the 2nd postoperative day. RESULTS: The experimental group revealed less time to the first postoperative passage of flatus and feces. No significant difference was found in resting and movement VAS between two groups. CONCLUSION: This study suggests that epidural naloxone reduces epidural morphine-induced intestinal hypomotility without reversing analgesic effects.

The Effects of Epidural Bupivacaine and Morphine Mixture on Bowel Motility after Upper Abdominal Surgery / 대한마취과학회지

BACKGROUND: The stress of operation inhibits bowel motility. The blockade of efferent sympathetic nerve is helpful to recovery of bowel motility. So we tried to examine that the extent of sympathetic blockade by alterations of bupivacaine infusion rate affected the recovery of bowel motility. METHODS: Group 1 (N = 25) received postoperative meperidine intramuscular injection on demand as a control group, group 2 (N = 25) received postoperative epidural 0.125% bupivacaine 100 ml plus morphine 10mg by infusion pump, 1 ml/hour, for 4days, group 3 (N = 25) received 0.125% bupivacaine 400 ml plus morphine 10mg by infusion pump, 4 ml/hour, for 4days. The Group 2 and 3 received additional morphine 2mg in 0.2% bupivacaine 10 ml epidurally as a single bolus when the peritoneum was closed. The time interval from termination of operation to the first passage of flatus was estimated. RESULTS: In group 1, bowel motility was regained at 92+/-23 hours, group 2 ; 90+/-19 hours and group 3 ; 91+/-19 hours. All values are not significantly different among the groups (p>0.05). CONCLUSIONS: The alteration of epidural bupivacaine and morphine infusion rate did not affect the recovery of postoperative bowel motility.