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ABSTRACT: Background Using an experimental model of colonic gas infusion, we previously showed that the abdominal walls adapt to its content by an active phenomenon of abdominal accommodation. We now hypothesized that abdominal accommodation is a physiological phenomenon, and aimed to confirm that it can be induced by ingestion of a meal; a secondary aim was to determine whether the response to gut filling is region-specific. Methods In healthy subjects (n = 24) a nutrient test meal was administered until tolerated at a rate of 50 mL min(-1) . Electromyographic (EMG) activity of the anterior wall (upper and lower rectus, external and internal oblique) was measured via four pairs of surface electrodes, and EMG activity of the diaphragm via intraluminal electrodes on an esophageal tube. To address the secondary aim, the response to gastric filling was compared with that induced by colonic filling (1440 mL 30 min(-1) anal gas infusion; n = 8). Key Results Participants tolerated 927 ± 66 mL of meal (450-1500 mL). Meal ingestion induced progressive diaphragmatic relaxation (EMG reduction by 16 ± 2%; P < 0.01) and selective contraction of the upper abdominal wall (24 ± 2% increase in activity of the upper rectus and external oblique; P < 0.01 for both), with no significant changes in the lower rectus (4 ± 2%) or internal oblique (5 ± 3%). Colonic gas infusion induced a similar response, but with an overall contraction of the anterior wall. Conclusions & Inferences Meal ingestion induces a metered and region-specific response of the abdominal walls to accommodate the volume load. Abnormal abdominal accommodation could be involved in postprandial bloating.
Neurogastroenterology and Motility 01/2013; · 3.41 Impact Factor
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ABSTRACT: We previously showed that changes in intra-abdominal content induce a volume-dependent muscular response of the anterior abdominal wall and the diaphragm. We aimed to determine the contribution of the thorax to abdominal accommodation and the influence of the intra-abdominal expansion rate.
Gas (1440 mL total load) was infused into the colon of nine healthy subjects, while abdomino-thoracic perimeters (by tape measure), electromyography (EMG) activity of the diaphragm (via six ring electrodes over an esophageal tube in the hiatus), intercostals and anterior abdominal wall (via five pairs of surface electrodes) and the position of the diaphragm by ultrasonography were measured. Infusion rates of 24, 48, and 96 mL min(-1) were tested on separate days.
Gas infusion induced anterior abdominal wall contraction (18 ± 1% EMG increment; P < 0.001) with relatively modest girth increment (4.9 ± 0.9 mm; P = 0.001), diaphragmatic relaxation (by 15 ± 1%; P < 0.001) with cephalad displacement (by 23 ± 6 mm; P = 0.005), and intercostal contraction (by 19 ± 2%; P < 0.001) with increased thoracic perimeter (by 2.0 ± 0.5 mm; P = 0.009). Responses were similar with the three infusion rates.
Accommodation of intra-abdominal loads involves a volume-related integrated abdomino-thoracic response regardless of the expansion rate.
Neurogastroenterology and Motility 12/2011; 24(4):312-e162. · 3.41 Impact Factor
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ABSTRACT: Determining the risk of rebleeding after endoscopic therapy for peptic ulcer bleeding (PUB) may be useful for establishing additional haemostatic measures in very high-risk patients.
To identify predictors of rebleeding after endoscopic therapy.
Bibliographic database searches were performed to identify studies assessing rebleeding after endoscopic therapy for PUB. All searches and data abstraction were performed in duplicate. A parameter was considered to be an independent predictor of rebleeding when it was detected as prognostic by multivariate analyses in ≥2 studies. Pooled odds ratios (pOR) were calculated for prognostic variables.
Fourteen studies met the prespecified inclusion criteria. Pre-endoscopic predictors of rebleeding were: (i) Haemodynamic instability: significant in 9 of 13 studies evaluating the variable (pOR: 3.30, 95% CI: 2.57-4.24); (ii) Haemoglobin value: significant in 2 of 10 (pOR: 1.73, 95% CI: 1.14-2.62) and (iii) Transfusion: significant in two of six (pOR not calculable). Endoscopic predictors of rebleeding were: (i) Active bleeding: significant in 6 of 12 studies (pOR: 1.70, 95% CI: 1.31-2.22); (ii) Large ulcer size: significant in 8 of 12 studies (pOR: 2.81, 95% CI: 1.98-4.00); (iii) Posterior duodenal ulcer location: significant in four of eight studies (pOR: 3.83, 95% CI: 1.38-10.66) and (iv) High lesser gastric curvature ulcer location: significant in three of eight studies (pOR: 2.86; 95% CI: 1.69-4.86).
Major predictors for rebleeding in patients receiving endoscopic therapy are haemodynamic instability, active bleeding at endoscopy, large ulcer size, ulcer location, haemoglobin value and the need for transfusion. These risk factors may be useful for guiding clinical management in patients with PUB.
Alimentary Pharmacology & Therapeutics 09/2011; 34(8):888-900. · 3.77 Impact Factor
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ABSTRACT: Intestinal manometry is the current gold standard for diagnosing small bowel dysmotility; however, the functional significance of abnormal manometry is unknown. Our aim was to determine whether, and to what extent, intestinal gas propulsion is impaired in patients with manometrically proven dysmotility compared with healthy controls and patients with IBS.
Clearance and tolerance of a jejunal gas load (12 mL min(-1) for 2 h) were measured in 15 patients with severe abdominal symptoms and intestinal dysmotility evidenced by manometry, 15 patients with IBS and 15 healthy subjects. Thereafter, the effect of neostigmine (0.5 mg i.v. bolus) vs placebo (i.v. saline) was tested in six dysmotility patients.
After 2-h gas infusion, patients with dysmotility developed significantly more gas retention (717 +/- 91 mL) than IBS patients (372 +/- 82 mL; P = 0.0037) and healthy subjects (17 +/- 67 mL; P < 0.0001 vs dysmotility; P = 0.0060 vs IBS). Despite the greater retention in dysmotility patients, abdominal perception (2.5 +/- 0.6 score) and distension (7 +/- 2 mm girth increment) were similar to IBS (3.9 +/- 0.6 score and 7 +/- 2 mm, respectively). In dysmotility patients, neostigmine produced immediate clearance of gas, and by 30 min had reduced gas retention (by -552 +/- 182 vs 72 +/- 58 mL after saline; P = 0.008), abdominal symptoms (by -0.8 +/- 0.3 score vs 0.3 +/- 0.2 after saline; P = 0.019) and distension (girth change -5 +/- 1 mm; P = 0.003 vs-2 +/- 2 mm after saline).
Patients with manometric dysmotility have markedly impaired intestinal gas propulsion. In IBS patients, impaired gas propulsion is less pronounced but associated with concomitant sensory dysfunction and poor tolerance of gas retention.
Neurogastroenterology and Motility 04/2010; 22(4):401-6, e91-2. · 3.41 Impact Factor
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ABSTRACT: The evidence on whether high-dose proton pump inhibitors (PPIs) increase cure rates of Helicobacter pylori treatment has not been previously assessed.
To evaluate the evidence on the usefulness of high-dose PPI in standard triple therapy by performing a systematic review and a meta-analysis.
A systematic search was performed in multiple databases and in the abstracts submitted to the Digestive Diseases Week, the European Helicobacter Study Group congress and the United European Gastroenterology Week. Randomized trials comparing a standard dose of a PPI with high-dose PPI both twice a day in triple therapy combining a PPI plus clarithromycin and either amoxicillin or metronidazole were selected. Relative risk (RR) and 95% confidence intervals (95% CIs) for all comparisons were calculated using Review Manager.
Six studies fulfilled the inclusion criteria. All used triple therapy for 7 days. A mean intention-to-treat cure rate of 82% was achieved with high-dose PPI and one of 74% with standard dose (RR: 1.09; 95% CI: 1.01-1.17). Subgroup analysis showed that the maximum increase was observed when the PPI compared were omeprazole 20 mg or pantoprazole 40 mg vs. esomeprazole 40 mg.
High-dose PPI seems more effective than standard-dose for curing H. pylori infection in 7-day triple therapy.
Alimentary Pharmacology & Therapeutics 10/2008; 28(7):868-77. · 3.77 Impact Factor
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ABSTRACT: The intestine propels and evacuates large gas loads without detectable phasic contractions by manometry. We hypothesized that intestinal gas motion is produced by changes in gut tone and capacitance. In 13 healthy subjects, changes in duodenal tone were measured by a barostat during continuous perfusion of lipids (Intralipid, 1 kcal min(-1)) into the duodenum for 60 min. In separate groups, the effects of jejunal gas infusion (N2, CO2 and O2 in venous proportions at 12 mL min(-1) starting after 15 min lipid perfusion) and sham infusion were tested. Gas outflow was collected continuously via an intrarectal cannula. Duodenal lipid perfusion produced a rapid duodenal relaxation (volume increased by 48 +/- 18%; P < 0.01 vs basal). Gas infusion increased gas evacuation (184 +/- 59 mL), and this was associated with a tonic contraction of the duodenum (R = 0.86; P < 0.01) that completely reverted the lipid-induced duodenal relaxation (volume decreased by 42 +/- 13%; P < 0.05). During sham infusion only 52 +/- 28 mL of gas were evacuated (P < 0.05 vs gas infusion), and the duodenum remained relaxed due to the effect of lipids (0 +/- 1% volume reduction; ns). In conclusion, intestinal gas propulsion and clearance is associated with a tonic contraction of the gut wall and reduced gut capacitance.
Neurogastroenterology and Motility 10/2006; 18(10):905-10. · 3.41 Impact Factor
