Recovery of gastrointestinal tract motility and myoelectric activity change after abdominal surgery.

OBJECTIVE: To investigate the relationship between fedstate gastrointestinal tract (GI) function and upper GI myoelectric changes seen after abdominal surgery. DESIGN: Twenty-one adult female mongrel dogs underwent either an open cholecystectomy, a laparoscopic cholecystectomy alone, or a laparoscopic cholecystectomy with peritoneal injury (n = 7 for each group). Bipolar recording electrodes were placed on the antrum and 3 sites of the proximal small intestine to record fasting myoelectric data each morning postoperatively. Solid-phase, technetium Tc 99m gastric emptying studies were performed on postoperative days 1 and 2. Radiopaque markers were ingested just before operation, and the excreted markers were counted using x-ray films of the feces. MAIN OUTCOME MEASURES: Postoperative fasting GI myoelectric activity, gastric emptying, and intestinal transit time. RESULTS: Migrating motor complexes (MMCs) in the small intestine were observed in 33.3% and 75.0% of the dogs on postoperative days 1 and 2, respectively. Gastric dysrhythmias were observed in 23.8% and 45.0% of the dogs on postoperative days 1 and 2, respectively. No relationship between type of surgery and the presence of MMCs or gastric dysrhythmias was noted. Gastric emptying was delayed on postoperative day 1 and was unrelated to the presence of MMCs. Transit time was not significantly delayed in dogs without MMCs on postoperative day 1 compared with that in dogs with MMCs on that day. The presence of gastric dysrhythmias did not affect transit time studies. CONCLUSION: Fasting GI myoelectric activity, including the return of MMCs and the presence of gastric dysrhythmias, does not accurately predict fed-state gastrointestinal GI function following abdominal surgery.

Gastric myoelectric activity changes following open abdominal surgery in humans.

We examined the postoperative changes in fasting gastric myoelectric activity in 11 patients undergoing nongastric surgery (colon surgery) via celiotomy. Recordings were performed on postoperative days (POD) 1, 2, 3, 5, and 7+ (7-35) for 1-1.5 hr after overnight fasting. Patients had placement of bipolar seromuscular recording electrodes on the proximal (N = 9) and distal (N = 11) antrum at the time of surgery. Data were analyzed visually and analysis of variance or tests of proportion were used for statistical analysis. Although there was a trend of decreasing slow wave frequency from POD 1 to 7+ in the proximal and distal antrum, no significant differences were observed in slow wave amplitude or in the percentage of slow waves with spike activity between postoperative day. In a few of the patients, several types of gastric dysrhythmias were infrequently observed. We conclude that certain parameters of fasting gastric myoelectric activity do not change sufficiently following open abdominal surgery to adequately reflect clinical recovery from postoperative ileus.

Gastrointestinal recovery following laparoscopic vs open colon surgery.

BACKGROUND: We prospectively studied the recovery of gastrointestinal motility in patients undergoing laparoscopic (LAP, n = 7) or open (OPEN, n = 7) colon resections. METHODS: At operation, bipolar recording electrodes were placed on the proximal and distal antrum, the proximal site of the colonic anastomosis, and the rectosigmoid for postoperative myoelectric recordings. RESULTS: Shorter postoperative hospitalization and earlier resumption of a regular diet of the LAP group just barely failed to achieve significant differences when compared with the OPEN group (p = 0.091, p = 0.050, respectively). There were no differences between groups for slow wave frequency, amplitude, or dysrhythmias in the antrum, nor for return of discrete (DERA) and continuous (CERA) electrical response activity in the colon. Percentage of slow waves with spike activity tended to increase with passage of time postoperatively in both groups. There was a significant difference between POD 3 and 7+ in the LAP group (p < 0.05). However, there were no significant differences in the percentage of slow waves with spike activities between groups on any postoperative day. CONCLUSIONS: The potential benefits of using a laparoscopic approach to colon resection are not clearly confirmed by these data. While such an approach may possibly result in shorter hospitalization, it appears to offer at best only modest increases in the rapidity of recovery of gastrointestinal function.

Recovery of fasted and fed gastrointestinal motility after open versus laparoscopic cholecystectomy in dogs.

OBJECTIVE: The authors investigate the recovery of gastrointestinal motility in the fed and fasted state after laparoscopic and open cholecystectomy. SUMMARY BACKGROUND DATA: Clinical recovery after laparoscopic cholecystectomy is known to be more rapid than after conventional open cholecystectomy. However, the actual effect of a laparoscopic approach on gastrointestinal motility, particularly fed-state motility, is not well investigated. METHODS: Laparoscopic (LAP, n=6) or open (OPEN, n=6) cholecystectomy was performed in 12 dogs. Bipolar recording electrodes were placed on the antrum, small intestine, and the transverse and descending colon, and fasting myoelectric data were recorded after operation. Solid meal gastric emptying studies were performed before surgery and on postoperative days 1 and 2. Transit time studies were performed using 10 radiopaque markers. RESULTS: Gastric emptying was significantly delayed in the OPEN group at 120 minutes on postoperative day 1 compared with pre-operative emptying (p<0.05), but was not delayed on postoperative day 2. Gastric emptying was not delayed in the LAP group after operation. Transit time was the same between groups. Gastric dysrhythmias were more frequent on postoperative day 3 (p<0.05) in the OPEN group. There were no significant differences in the presence, cycle length, or propagation velocity of the migrating motor complex on any postoperative day. Discrete or continuous electrical response activity in the colon was observed by postoperative day 1 in both groups. CONCLUSIONS: Fed-state motility is the only parameter for which laparoscopic cholecystectomy showed an improvement in postoperative recovery. Recovery of fasted gastrointestinal motility in dogs is equally rapid after either operation.