Can Propofol Be Used to Assess the Presence of the Rectoanal Inhibitory Reflex During Anorectal Manometry Studies?

OBJECTIVES: To study changes in intra-anal pressure (IAP) and characteristics of the rectoanal inhibitory reflex (RAIR) during anorectal manometry (ARM) in patients undergoing anesthesia induction with propofol. METHODS: Prospective study in which ARM was performed at baseline while patients were awake and repeated after propofol-induced anesthesia. We studied IAP and the presence and characteristics of the RAIR before and after propofol. RESULTS: A total of 27 patients were included (63% male; 9.2 years). Three patients had obstructive symptoms after Hirschsprung disease repair (HSCR), and 24 had intractable constipation. At baseline, the RAIR was present on 21 of 27 patients and absent on 6 of 27. Of the six patients with an absent RAIR, it remained absent in four of six (three known HSCR, and one new diagnosis of IAS achalasia), and two of six had a normal RAIR during propofol. Therefore, RAIR was present in all patients with constipation. The mean resting IAP was significantly lower after propofol. The percentage of IAS relaxation after lower balloon volume inflations was significantly higher during propofol (P < 0.05). No difference was observed over the latency time or the total relaxation time after propofol. CONCLUSIONS: Propofol can be used to assess the presence of the RAIR during ARM in children who are uncooperative and undergoing other procedures under anesthesia. On the other hand, propofol significantly reduces the resting IAP and increases the percentage of internal anal sphincter relaxation after balloon distention. These findings may impact the interpretation to decide if an intervention is needed, or if there is a possible spinal neuropathy.

Duodenal and proximal jejunal motility inhibition associated with bisacodyl-induced colonic high-amplitude propagating contractions.

Bisacodyl is a stimulant laxative often used in manometric studies of pediatric constipation to determine if it can initiate propulsive high-amplitude propagating contractions (HAPCs). Whereas the effects of bisacodyl infusion on colonic motility are well described, the effects of the drug on other regions of the gut after colonic infusion are not known. The aim of the present study was to characterize the effects of bisacodyl on both colonic and small bowel motility. Twenty-seven children (9.3 ± 1.2 yr) undergoing simultaneous high-resolution antroduodenal and colonic manometry were included. Small bowel and colonic motor patterns were assessed before and after colonic infusion of bisacodyl. Patients were divided into two groups: responders and nonresponders based on the presence of high-amplitude propagating contractions (HAPCs) after bisacodyl infusion. Nineteen patients were responders. A total of 188 postbisacodyl HAPCs was identified with a mean count of 10.4 ± 5.5 (range, 3-22), at a frequency of 0.6 ± 0.2/min and mean amplitude of 119.8 ± 23.6 mmHg. No motor patterns were induced in the small bowel. However, in the 19 responders the onset of HAPCs was associated with a significant decrease in small bowel contractile activity. In the nonresponders, there was no detectable change in small bowel motility after bisacodyl infusion. Bisacodyl-induced HAPCs are associated with a significant reduction in small bowel motility probably mediated by extrinsic sympathetic reflex pathways. This inhibition is potentially related to rectal distension, caused by the HAPC anal propulsion of colonic content.NEW & NOTEWORTHY The present study has shown, for the first time, that the presence of high-amplitude propagating contractions induced by bisacodyl is associated with a significant reduction in small bowel motility. These findings support of possible existence of a reflex pathway that causes inhibition of small bowel motility in response to rectal distension.

Diagnostic and clinical utility of the wireless motility capsule in children: A study in patients with functional gastrointestinal disorders.

BACKGROUND: The wireless motility capsule (WMC) evaluates gastrointestinal motility and transit simultaneously. We evaluated the utility of the WMC in children with functional gastrointestinal symptoms. METHODS: Study in children comparing WMC transit and motility parameters between those with upper (UGI) or lower (LGI) gastrointestinal symptoms, nuclear medicine gastric emptying time (NMGET) and/or a colonic radiopaque marker (CROM) study. KEY RESULTS: We prospectively recruited 57 children (median age 16.45y, range 8.78-17.8y, 44 Female) and 50 completed the study (24 UGI/26 LGI). We found no association between WMC study interpretation, motility and transit parameters and symptoms. WMC and NMGET interpretation agreement observed in 24/34 (70%) (κ = 0.351, p = 0.026) and with CROM in 17/21 (81%) patients (κ = 0.576, p = 0.007). WMC detected abnormal gastric transit in 41% vs. 24% with NMGET (p = 0.04) and abnormal colon transit in 62% vs. 71% of patients by CROM (p = 0.01). We found significant correlation (r = 0.574, p = 0.01) and no difference in median colon transit (p = 0.421) by WMC and CROM. A single WMC motility parameter, mean peak amplitude, was associated with NMGET (p = 0.04), none with CROM. Capsule retention >5 days (n = 9, all passed <2 weeks) was associated with prolonged colon transit, not with symptoms, age and gender. CONCLUSIONS: WMC is well tolerated in children as young as 8 years old. We found no association between WMC and symptoms, fair agreement with NMGET and strong agreement with CROM. WMC increases the yield of finding gastrointestinal transit abnormalities. Capsule retention in children is associated to prolonged colon transit. Larger studies are needed to further validate these findings.

Same day versus next day antroduodenal manometry results in children with upper gastrointestinal symptoms: A prospective study.

BACKGROUND: We evaluated the changes in antroduodenal manometry (ADM) parameters and interpretation when the test is performed the day of catheter placement and the following day. METHODS: Catheter was placed endoscopically under anesthesia and recorded on day 1 and repeated on day 2. Study parameters including antrum and small bowel motility index (MI) during fasting, meal, postprandial, erythromycin (EES), and octreotide (OCT) challenge phases, the presence of the phase III of the migrating motor complex (MMC), visual postprandial response, and study interpretation were compared between both days. KEY RESULTS: Twenty patients were studied. Antrum and small bowel MI during fasting, postprandial, and EES challenge phases were significantly higher on day 2 than on day 1 (P < 0.05). The proportion of patients having a phase III of the MMC was significantly higher on day 2 compared to day 1 (65% vs 15%; P = 0.006). Study interpretation changed from day 1 to day 2. On day 1, 70% of the patients had a normal study and 30% had an abnormal study. On day 2, 67% of the patients with an abnormal study on day 1 changed to normal and 33% remained abnormal. All patients with a normal study on day 1 remained normal on day 2. CONCLUSIONS AND INFERENCES: ADM parameters are affected the day of catheter placement. The MI and presence of the phase III of the MMC were significantly higher on day 2 compared to day 1. Overall, ADM study interpretation changed from day 1 to day 2 in 20% of the patients.