Solid Meal Research Articles

Laparoscopic partial posterior (Toupet) fundoplication improves esophageal bolus propagation on scintigraphy

Impaired esophageal clearance is important in the pathogenesis of gastroesophageal reflux disease (GERD). It is unknown whether esophageal clearance improves following antireflux surgery. The aim of this study was to investigate the effect of laparoscopic Nissen fundoplication (NF), laparoscopic partial posterior (Toupet) fundoplication (PPF) or medical therapy on esophageal clearance. This was a prospective nonrandomized crossover study. Sixty patients were evaluated with endoscopy, esophageal manometry, radionuclide scanning of esophageal emptying, and assessment of symptoms prior to surgery or medical therapy and 6 months after treatment. In 20 GERD patients with normal esophageal peristalsis an NF was performed, in 20 patients with impaired esophageal peristalsis a PPF was chosen, and 20 patients received proton-pump inhibitor (PPI) treatment. On endoscopy, esophagitis had resolved in all patients after surgery; two patients with medical therapy still had esophagitis. On manometry, a significant improvement of lower esophageal sphincter competence was seen in both surgical groups. LES relaxation was complete after PPF, but incomplete after NF. Esophageal peristalsis did not improve after medical therapy, was significantly improved after PPF, but had worsened after NF. On scintigraphic esophageal emptying for solid meals, there was no improvement after medical therapy but a significant improvement after PPF. A significant deterioration of esophageal emptying was observed after NF. There was a strong correlation between scintigraphic and manometric evaluation of peristalsis preoperatively (r(s) = -0.87, p < 0.05) and postoperatively (r(s) = -0.82, p < 0.05). There was no change in dysphagia after medical therapy and after NF but a significant improvement after PPF. Globus sensation was significantly improved after PPF but did not change after medical therapy or NF. Postprandial bloating and inability to belch were significantly more common after NF than after PPF. Laparoscopic partial posterior (Toupet) fundoplication can restore a preoperatively defective esophageal bolus propagation on scintigraphy with the same antireflux effect as the laparoscopic Nissen fundoplication, but with lower side-effects.

Total Fundoplication Does Not Obstruct the Esophageal Secondary Peristalsis: Investigation with Pre- and Postoperative 24-Hour pH-Multichannel Intraluminal Impedance

Aim: To determine the impact of total fundoplication on the spontaneous esophageal clearance, known as secondary peristalsis. Background: Although there is general agreement that total fundoplication is not an obstacle to bolus swallowing (primary peristalsis), whether it is an obstacle to spontaneous esophageal clearance (secondary peristalsis) is still not clear. Based on 24-hour monitoring, multichannel intraluminal impedance was used to calculate the time of spontaneous bolus clearance (BCT). Methods: Mean BCT was prospectively calculated in 15 consecutive patients before and after total fundoplication. BCT was calculated in seconds including all the gastroesophageal reflux episodes, whereas bolus swallows (solid meals and liquid swallows) were excluded from the analysis. Results: BCT was extrapolated from 1,057 episodes in the 623 h of study. Overall, BCT did not change after surgery (13.6 ± 4 vs. 15.2 ± 10 s; p = nonsignificant) and in the upright (12.2 ± 3 vs. 16.5 ± 7 s; p = nonsignificant) and recumbent position (22.9 ± 9 vs. 23.0 ± 9 s; p = nonsignificant). Conclusions: In this study total fundoplication did not affect the BCT by combined 24-hour ph monitoring and multichannel intraluminal impedance.

Studies of gastric emptying time in patients with non-ulcer dyspepsia

To assess the gastric emptying pattern of a standardized solid meal in patients with non-ulcer dyspepsia by using scintigraphic techniques. Results for the half-emptying time for solids (T1/2) and percent clearance of solid meal at 60 min (C60) of patients (n=35) having non-ulcer dyspepsia according to Rome II criteria were compared with age- and sex-matched controls (n=28). Gastric emptying was studied by using egg omelette labelled with Tc tin colloid. Data acquisition was done using two protocols: dynamic acquisition was performed for the first 100 min and then static acquisition was carried out for up to 4 h. T1/2 and C60 were calculated from the computer-generated time-activity curve. The normal range of T1/2 was 29-88 min (mean+/-2 SD) among the control group. The mean T1/2 of the patient group was 160.1+/-96.1 min (P<0.01). Twelve of 22 male patients and 11 of 13 female patients had prolonged T1/2. The normal range of C60 was 92-28% (mean+/-2 SD) in the control group. The mean C60 of the patient group was 33.1+/-18.5% (P<0.01). Fifteen of 22 male patients and 11 of 13 female patients had shortened C60. Gastric emptying is significantly delayed in both men and women having non-ulcer dyspepsia as the T1/2 is prolonged and the C60 is shortened in a significant number of these patients. Radionuclide tests might offer an objective way of assessing this particular aspect of gastric physiology.

Rabeprazole delays gastric emptying of a nutrient liquid

It is generally considered that gastric acid suppression delays gastric emptying of solid meals because gastric hypoacidity impairs peptic digestion and antral triturition. Rabeprazole is one of the most potent acid suppressants. We conducted this cross-over study to investigate if rabeprazole delays gastric emptying of liquid nutrients, for which peptic digestion is unnecessary. On two randomized occasions, 13 healthy male volunteers underwent the (13)C-acetate breath test following ingestion of a 300 kcal-liquid meal. On one occasion, they had received 20 mg rabeprazole for the preceding 2 days and 1 h before the test. On another, they took no pretreatment. Based on 4 h breath samples, the half (13)CO(2) excretion time (t(1/2b)) and the time of maximal excretion (t(max)) were calculated as overall measures of gastric emptying. In addition, time profiles of gastric emptying were generated using the Wagner-Nelson analytical method, which creates the gastric emptying curve as accurately as the scintigraphy. Rabeprazole significantly prolonged t(max) but unchanged t(1/2b). The gastric emptying profiles showed that rabeprazole evoked a segmental slowing of gastric emptying during 0.5-1.25 h of post-meal ingestion. Rabeprazole suppresses gastric emptying of a liquid nutrient 0.5 h after meal ingestion. We have speculated that: (i) rabeprazole delays gastric emptying via a mechanism other than acid-pepsin maldigestion; and (ii) rabeprazole may intensify the post-gastric feedback regulation system (>0.5 h of post-meal).

Predictors of Response in Gastroparesis

Purpose: Natural history and outcomes of gastroparesis are not well known and the response to treatment is variable. We aim to determine which clinical features could help identify patients with response to therapy. Methods: 69 patients were included. Symptoms were scored using the Gastroparesis Cardinal Symptom Index, a validated scale of severity that utilizes three clusters (nausea/vomiting, post-prandial fullness/satiety, and bloating). Gastric emptying was measured using a standard 4-hour low fat solid meal. Treatment included conservative measures like antiemetics, prokinetics, antidepressants, analgesics. Interventions included enteral feeding and pacing in selected patients. Response to treatment was defined as overall change in GCSI score of 33% or more as compared with baseline. Results: 29 out of 69 patients had diabetes. 40 had idiopathic gastroparesis. 49 were responders (71%). 20 were non responders (29%). Amongst responders 17 (34.69%) patients required enteral feeding and 10 (20.41%) patients underwent enterra placement as opposed to 8(42.11%) and 4(21.05%) respectively in non responders. 52 patients had delayed gastric emptying (75%). Proportion of responders was not different amongst patients with delayed or normal emptying. Demographic characteristics or subtype of gastroparesis (diabetic/idiopathic) did not significantly differ among responders and non-responders. Baseline scores for nausea, vomiting and retching were similar. However, baseline scores for early satiety (P= 0.02), postprandial fullness (P= 0.05), stomach distension (P= 0.0001) and bloating (P= 0.01) were significantly greater in non-responders. Conclusion: Majority of patients with gastroparesis improve with therapy. Specific symptoms seem to be of a predictive value, with severity of early satiety, postprandial fullness, stomach distension and bloating being significantly higher in non responders than responders. On the other hand, neither the type of gastroparesis nor gastric emptying pattern appeared to predict response. Future studies are needed to investigate whether the clinical phenotype of non-responders is associated with distinctive changes in gastric pathophysiology.

Autonomic regulation of digestive function during stress: Role of brain peptides

Various stressors impacts on the gut function resulting in the inhibition of gastric and stimulation of colonic motor function and increased visceral pain to colorectal distention (CRD). Stress activates brain CRF system that encompasses the peptide corticotropin releasing factor (CRF), and related urocortin (Ucn ) 1, Ucn 2 and Ucn 3 and two distinct CRF1 and CRF2 receptors. CRF has preferential affinity toward the CRF1 receptor while Ucn 1 has equal affinity to both receptors and Ucn 2 and Ucn 3 are selective ligands for CRF2. Intracisternal injection of CRF, Ucn 1 and Ucn 2 inhibit gastric emptying of liquid or solid meal through CRF2 receptors modulating vagal and sympathetic outflow to the stomach (decrease vagal efferent and increased sympathetic activity) in rats and mice. Various stressors (ether, partial restraint, peritoneal irritation, swim stress, abdominal surgery, interleukins) induce 30–80% inhibition of gastric emptying that is prevented by central injection of CRF antagonists. Only acute cold stress exposure stimulates gastric motor function through activation of medullary thyrotropin releasing hormone (TRH) cell bodies in the raphe pallidus, raphe obscurus and parapyramidal region that project to the dorsal motor nucleus (DMN). Activation of TRH1 receptor on DMN neurons by TRH results in stimulation of gastric vagal efferent discharges, activation of gastric myenteric cholinergic neurons and related increase of gastric secretion (acid, pepsin, histamine, serotonin, mucus) and gastric motor function ( motility and emptying) in rats. With regards to the colon, various stressors (partial restraint, water avoidance, open field test) stimulates propulsive motor function in rodents that is mimicked by central injection of CRF into the cerebrospinal fluid, paraventricular nucleus of the hypothalamus (PVN) or locus coeruleus/subcoeruleus (LC/SC) in rats. Water avoidance activates neurons in the PVN, LC/SC, sacral spinal parasympathetic nucleus and colonic myenteric ganglia resulting in increased parasympathetic outflow and cholinergic enteric neurons stimulating colonic motility, transit and defecation. Central injection of CRF antagonists reduced by 50% brain neuronal activation selectively in the PVN and LC and defecation response to water avoidance and blocked the induction of rapid distal colonic transit in rats. The stress-colonic stimulatory response is mediated by CRF1 receptors as shown by pharmacological approaches using selective CRF1 antagonists and CRF1 knockout mice and is also involved in visceral hypersensitivity to CRD induced stress. These studies provide insight to specific brain peptidergic pathways namely the CRF system recruited by stressors that impacts on digestive function through autonomic-gut enteric nervous system interactions.

Free Fatty Acids Have More Potent Effects on Gastric Emptying, Gut Hormones, and Appetite Than Triacylglycerides

The effects of fat on gastric emptying (GE), gut hormones, and energy intake are dependent on digestion to free fatty acids (FFAs). In animals, small intestinal oleic acid inhibits energy intake more potently than the triacylglyceride (TG) triolein, but there is limited information about the comparative effects of FFA and TG in human beings. We compared the effects of FFA and TG on GE, gut hormone secretion, appetite, and energy intake in healthy males. Nine men (age, 23 +/- 2 y; body mass index, 22 +/- 1 kg/m(2)) were studied on 3 occasions to evaluate the effects of (1) 40 g oleic acid (FFA, 1830 kJ), (2) 40 g macadamia oil (TG, 1856 kJ; both 600-mL oil-in-water emulsions stabilized with 4% milk protein and labeled with 15 MBq (123)I), or (3) 600 mL 4% milk protein (control, 352 kJ), administered intragastrically, on GE, plasma cholecystokinin (CCK) and peptide-YY (PYY) levels, appetite perceptions, and subsequent energy intake. GE of FFA was much slower than that of TG (P < .05), with greater retention of FFA, than TG, in the proximal stomach (P < .001). Hunger was less (P < .05), and fullness was greater (P < .05), after FFA when compared with control and TG. Increases in plasma CCK and PYY levels were greater after FFA than TG or control (P < .05). Energy intake tended to be less after FFA compared with TG (control, 4754 +/- 610 kJ; TG, 5463 +/- 662 kJ; FFA, 4199 +/- 410 kJ). FFAs empty from the stomach more slowly, but stimulate CCK and PYY and suppress appetite more potently than TG in healthy human beings.

Impaired Emptying of the Retained Distal Stomach Causes Delayed Gastric Emptying after Pylorus‐preserving Pancreaticoduodenectomy

Delayed gastric emptying (DGE) is the major morbidity after pylorus-preserving pancreaticoduodenectomy (PPPD). Gastroscintigraphy was used to characterize food distribution in the proximal and distal stomach during emptying. Between October 2000 and June 2003, 20 healthy volunteers and 23 PPPD patients underwent single-phase gastric emptying scintigraphy 14 days after surgery. Scintigraphic studies of the stomach were divided into proximal and distal regions, and the ratio of proximal to distal radiation counts (P/DR) was plotted. Momentary monitor-displayed images were compared to evaluate meal distribution during emptying. There were 21 eligible patients, 12 without symptoms of DGE (sDGE-) and 9 with symptoms of DGE (sDGE+). In healthy volunteers the mean P/DR value was maintained at a level of > or = 2.5, and momentary images showed dilated proximal and constricted distal stomach throughout meal emptying. In both the solid and liquid phase tests, the average P/DR value for sDGE- patients was slightly lower than that for healthy volunteers, and momentary images showed early emptying of the solid meal. The mean P/DR value for sDGE+ patients was abnormally low and remained constant throughout the assessment. Momentary images showed significant dilatation of the distal stomach, with constant full size. The odds ratio for the change in P/DR per minute decreased after surgery, especially in sDGE+ patients, indicating a loss of contractility of the distal stomach. At the 6-month follow-up, the P/DR values exhibited a normal decreasing trend but were lower for sDGE+ patients than for healthy volunteers. The P/DR curve provides new insight into normal and pathological gastric function. After surgery, temporary loss of contractility of the distal stomach causes symptoms of DGE.

Dynamic antral scintigraphy following solid and liquid meals in healthy human subjects

Dynamic antral scintigraphy (DAS), a non-invasive technique for the assessment of post-prandial gastric contractions, has been used to demonstrate abnormal contractility in several clinical conditions. The objective of the present study was to assess differences between solid and liquid meals regarding gastric contractions in healthy volunteers using DAS. Ten healthy male volunteers were studied after ingesting solid or liquid meals [approximately 1670 kJ (approximately 400 kcal)] labelled with 99mTc phytate and administered in a random order. Gastric images were acquired for 120 min for gastric emptying half-time (T1/2) measurement. Dynamic (1 frame x s(-1)) images of the gastric antrum were acquired at 30 min intervals for 4 min for the assessment of antral contractility. Gastric emptying T1/2 values for solid and liquid meals were similar (58.1+/-19.06 min vs. 69.4+/-6.76 min; P=0.13). For the solid meal, average values for both frequency (3.08+/-0.15 cycles x min(-1) vs. 2.78+/-0.18 cycles x min(-1); P=0.003) and amplitude (33.94+/-5.2% variation vs. 24.09+/-7.37% variation; P=0.002) of antral contractions were significantly higher than those obtained with the liquid meal. For either of the test meals, none of the antral contractility variables correlated with gastric emptying T1/2. Dynamic antral scintigraphy is capable of detecting differences between solid and liquid meals concerning post-prandial gastric antral contractions under physiological conditions. The frequency and amplitude of gastric antral contractions after a solid meal are greater than after an exclusively liquid meal of similar calorie content, in spite of lack of a difference regarding gastric emptying.

Autonomic nervous system response to a solid meal and water loading in healthy children: its relation to gastric myoelectrical activity

The aim of this study was to investigate the correlation of gastric myoelectrical and autonomic activities in healthy children. Simultaneous recordings of electrogastrography (EGG) and electrocardiogram (ECG) were performed in healthy children before and after a solid meal and water loading respectively. The autonomic activity was assessed by spectral analysis of the heart rate variability (HRV). The solid meal resulted in an increase in EGG-dominant frequency (2.92 cpm vs 3.16 cpm, P < 0.05), dominant power (46.9 dB vs 53.7 dB, P < 0.05) and percentage normal slow waves (81.9%vs 89.0%, P < 0.05), while only dominant power increased following water loading. Power in the low-frequency band of HRV (LF) was significantly increased and power in the high-frequency band of HRV (HF) significantly decreased following the solid meal. Postprandial LF was positively and HF negatively correlated with the postprandial increase in EGG-dominant power. Water loading was not associated with any significant changes in HRV parameters. These results suggest that both vagal and sympathetic pathways are involved in modulation of gastric myoelectrical activity.

Gastroparesis in patients with inactive Crohn's disease: a case series

BackgroundFew studies have described patients with foregut dysmotility in inflammatory bowel disease. The aim of this case series was to evaluate clinical characteristics of 5 patients with inflammatory bowel disease and symptoms and signs of upper gut dysmotility.Case presentationsWe describe a series of four patients with Crohn's disease and one with indeterminate colitis who presented with severe symptoms and signs of gastroparesis. We reviewed medical records of all cases. Gastric emptying of a solid meal was assessed by scintigraphy. Small bowel enteroclysis, gastroduodenoscopy and colonoscopy with biopsies were performed to estimate the activity of the disease and to exclude organic obstruction. None of the patients had any signs of active inflammation or stricture. All of the patients had markedly delayed gastric emptying with a mean t 1/2 of 234 minutes (range 110–380 minutes; normal values 54–94 minutes).ConclusionClinicians should consider impaired gastric emptying when evaluating patients with Crohn's disease and severe symptoms of upper gut dysmotility, which cannot be attributed to active inflammation or organic obstruction of the digestive tract. Symptoms in these patients are refractory to various therapeutic interventions including tube feeding and gastric surgery.

Glucagon-like peptide 1 (GLP-1) suppresses ghrelin levels in humans via increased insulin secretion

Introduction Ghrelin is an orexigenic peptide predominantly secreted by the stomach. Ghrelin plasma levels rise before meal ingestion and sharply decline afterwards, but the mechanisms controlling ghrelin secretion are largely unknown. Since meal ingestion also elicits the secretion of the incretin hormone glucagon-like peptide 1 (GLP-1), we examined whether exogenous GLP-1 administration reduces ghrelin secretion in humans. Patients and methods 14 healthy male volunteers were given intravenous infusions of GLP-1(1.2 pmol·kg − 1 min − 1 ) or placebo over 390 min. After 30 min, a solid test meal was served. Venous blood was drawn frequently for the determination of glucose, insulin, C-peptide, GLP-1 and ghrelin. Results During the infusion of exogenous GLP-1 and placebo, GLP-1 plasma concentrations reached steady-state levels of 139 ± 15 pmol/l and 12 ± 2 pmol/l, respectively ( p < 0.0001). During placebo infusion, ghrelin levels were significantly reduced in the immediate postprandial period ( p < 0.001), and rose again afterwards. GLP-1 administration prevented the initial postprandial decline in ghrelin levels, possibly as a result of delayed gastric emptying, and significantly reduced ghrelin levels 150 and 360 min after meal ingestion ( p < 0.05). The patterns of ghrelin concentrations in the experiments with GLP-1 and placebo administration were inversely related to the respective plasma levels of insulin and C-peptide. Conclusions GLP-1 reduces the rise in ghrelin levels in the late postprandial period at supraphysiological plasma levels. Most likely, these effects are indirectly mediated through its insulinotropic action. The GLP-1-induced suppression of ghrelin secretion might be involved in its anorexic effects.

Gastric Emptying of Solids and Semi-solids in Morbidly Obese and Non-obese Subjects: An Assessment Using the 13C-Octanoic Acid and 13C-Acetic Acid Breath Tests

It has been suggested that obesity is associated with an altered rate of gastric emptying. The objective of the present study was to determine whether the rates of solid and semi-solid gastric emptying differ between morbidly obese patients and lean subjects. The Gastric-emptying time (GET) of solid and semi-solid meals were compared between lean healthy subjects and morbidly obese patients enrolled in two previously published studies. GET of solid and semi-solid meals was measured using the 13C-octanoic acid breath test and 13C-acetic acid breath test, respectively, in 24 lean and 14 morbidly obese individuals of both sexes. Student t-test was used to compare the mean data between the lean and morbidly obese groups. The influence of sex, gender, BMI and morbid obesity on the GET of solid meals was verified by linear regression analysis. Mean t(1/2) values of solid GET (+/- standard deviation) were 203.6 +/- 76.0 min and 143.5 +/- 19.1 min for lean and obese subjects, respectively (P = 0.0010). Mean t(lag) values of solid GET were 127.3 +/- 42.7 min and 98.4 +/- 13.0 min for lean and obese subjects, respectively (P = -0.0044). No significant difference in semi-solid GET was observed between the lean and morbidly obese groups. The present study demonstrated a significantly enhanced gastric emptying of the solid meal test in morbidly obese patients when compared to lean subjects. This finding is compatible with the hypothesis that rapid gastric emptying in morbidly obese subjects increases caloric intake due to a more rapid loss of satiety.

Fasting and postprandial small intestinal slow waves non‐invasively measured in subjects with total gastrectomy

Slow wave is essential to initiate gastrointestinal tract motility. Subjects with total gastrectomy (TG) provide an opportunity to study small intestinal slow wave in the absence of stomach interference. The aims of this study were to determine the origin of 3 cycles per min (cpm) slow wave recorded via electrogastrogram (EGG) and the characteristics of putative small intestinal slow waves in TG subjects. Thirty-three subjects with TG (25 male, age: 44-83 years) were consecutively enrolled. In each subject, the myoelectricity-like signals of the gastrointestinal tract were recorded using 3-channel EGG. Fourier transform-based spectral analysis was performed to derive the EGG parameters including dominant frequency/power, % normal rhythm (2-4 cpm), and power ratio. Neither visual nor spectral analysis of the EGG revealed any waves at a frequency of about 3 cpm. The most frequently observed peaks in the power spectra of all subjects were those at approximately 1, approximately 6 and approximately 11 cpm with occurrences of 97%, 6.1% and 90.9%, respectively. Based on visual analysis of all recorded signals, the approximately 11 cpm signal was exactly rhythmically recorded rather than the approximately 1 cpm. The recorded approximately 11 cpm wave had a frequency of 10.9 +/- 1.0 cpm in the fasting state and 10.9 +/- 1.3 cpm in the fed state (NS), and a power of 31.5 +/- 3.2 dB in the fasting state and 35.2 +/- 3.8 dB in the fed state (P < 0.0001). None of other factors, including sex, age, and body mass index, had any impact on this approximately 11 cpm wave. Small intestinal slow wave can be recorded non-invasively using EGG via cutaneous electrodes in TG subjects. Sex, age and body mass index have no effect on the intestinal slow waves. The power rather than frequency of intestinal slow wave is increased after a solid meal.

High‐resolution solid‐state manometry of the antropyloroduodenal region

Manometric recording from the pyloric channel is challenging and is usually performed with a sleeve device. Recently, a solid-state manometry system was developed, which incorporates 36 circumferential pressure sensors spaced at 1-cm intervals. Our aim was to use this system to determine whether it provided useful manometric measurements of the pyloric region. We recruited 10 healthy subjects (7 males:3 females). The catheter (ManoScan(360)) was introduced transnasally and, in the final position, 15-20 sensors were in the stomach and the remainder distributed across the pylorus and duodenum. Patients were recorded fasting and then given a meal and recorded postprandially. Using pressure data and isocontour plots, the pylorus was identified in all subjects. Mean pyloric width was 2.1 +/- 0.1 cm (95% CI: 1.40-2.40). Basal pyloric pressure during phase I was 9.4 +/- 1.1 mmHg, while basal antral pressure was significantly lower (P = 0.003; 95% CI: 2.4-8.4). Pyloric pressure was always elevated relative to antral pressure in phase I. For phases II and III, pyloric pressure was 7.7 +/- 2.3 mmHg and 9.4 +/- 1.1 mmHg, respectively. Pyloric pressure increased similarly after both the liquid and solid meal. In addition, isolated pressure events and waves, which involve the pylorus, were readily identified.

Extracirculatory effects of noise of various frequency spectra in humans-effect of pink and blue noise on gastric myoelectrical activity and gastrointestinal passage of nutrients

Recent investigations in humans point out to a disturbing effect of auditory stimuli on the functional integrity of the brain-gut axis. The study was devoted to a systematic comparative evaluation of the effect of noises of different frequency spectra on the postprandial electrical and transport functions of the digestive tract in humans. Twenty six healthy subjects attended a cross-over study, which aimed at comparison of the effect of pink contrasted to blue noise within a given category (band or tonal) and a meal stimulus type (semi-liquid or solid test meal). A panel of noninvasive measurement methods was applied: heart rate variability (HRV) analysis, surface electrogastrography, (13)CO(2) breath tests for gastric emptying (GE), lactulose hydrogen breath test for orocecal transit time (OCTT). The blue tonal noise was rated the most annoying one, whereas solely the pink noises exerted discernible cardiovascular effects. No one of the four noises was capable of overriding the meal-induced preponderance of the sympathetic tone. The postprandial gastric myoelectrical activity and the GE of either the semiliquid or the solid test meal appeared to be ;resistant' to the noise exposure, irrespective of the noise type. Similar was the finding in the case of the OCTT, with the exception of a statistically significant retardation of the OCTT with the blue band noise. Ingestion of mixed caloric meals seems to elicit a protective influence against noise-elicited derangements of the functional integrity of the digestive tract proven formerly to occur during the fasting period.

Stepped assessment of gastric emptying of a solid meal using the 13C-octanoic acid breath test

The (13)C-octanoic acid breath test is widely used for evaluating gastric emptying of solids. Since the results of this test are influenced by multiple factors such as the time required to grind the solid meal into smaller particles, the gastroduodenal transport time of the ground meal, and the time required for bowel drug absorption and drug dispersion, the administration of a test meal by the oral route alone cannot result in an accurate measurement of the complicated process of emptying the stomach of solids. The aim of the present study was to evaluate each phase of gastric emptying of solids by varying the administration route of the test meal. Six healthy male volunteers (mean age: 33.2 yr) participated in the study. The test meal consisted of a bowl of rice topped with a mixture of boiled chicken and eggs admixed with 100 mg of (13)C-octanoic acid (total: 273 kcal). All subjects were given the test meal by each of the following three methods: 1. Normal oral intake of the test meal, 2. Feeding of the ground test meal through a nasogastric tube, 3. Feeding of the ground test meal through a duodenal tube. For each set of examinations, the mean residence time (MRT), half-emptying time (T(1/2)), gastric emptying coefficient (GEC), lag phase (L-breath), and measured maximum (13)C excretion time (Tmax-measured) were calculated. The data was analyzed to determine the time for each phase of gastric emptying as follows: mean grinding time (MGT) = MRT(oral) - MRT(nasogastric), mean gastroduodenal transport time (MGDTT) = MRT(nasogastric) - MRT (nasoduodenal). Data was expressed as the mean +/- SE. The values of the parameters of MGT were 0.82 +/- 0.50 hr (MRT), 0.64 +/- 0.18 hr (T(1/2)), 0.51 +/- 0.24 hr (L-breath), -0.45 +/- 0.30 hr (GEC), and 49.2 +/- 8.0 min (Tmax-measured). The values of the parameters of MGDTT were 0.87 +/- 0.38 hr (MRT), 0.26 +/- 0.29 hr (T(1/2)), 0.92 +/- 0.36 hr (L-breath), 0.55 +/- 0.23 hr (GEC), and 63.33 +/- 8.16 min (Tmax-measured). The times required for the drug absorption and disposition were 1.60 0.20 hr (MRT), 1.03 +/- 0.24 hr (T(1/2)), 0.10 +/- 0.08 hr (L-breath), 3.72 +/- 0.46 hr (GEC), and 19.67 +/- 2.11 min (Tmax-measured). By varying the administration route of a test meal containing (13)C-octanoic acid, we may be able to assess each phase of the emptying of gastric solids in detail, thus leading to a better understanding of gastroduodenal motility.

Liquid and solid gastric emptying in adults treated for Hirschsprung's disease during early childhood

Objective. Dysmotility of the upper gastrointestinal tract has been reported in children with Hirschsprung's disease. In the present study, gastric emptying was studied in adult patients with Hirschsprung's disease to elucidate whether there is a persisting involvement of the upper gastrointestinal tract in this group of patients. Material and methods. Gastric emptying of caloric liquids and solids was studied in 16 adult patients with surgically treated Hirschsprung's disease during early childhood and in age-matched controls. To examine liquid emptying, the paracetamol absorption test was applied using a meal containing glucose, lactose, maize oil, water (2020 kJ) and paracetamol. To examine solid emptying, the 13C gastric emptying breath test was applied using a meal containing white bread, margarine, a one-egg omelette (1050 kJ) and [13C]-octanoic acid. Gastrointestinal symptoms were recorded according to a standardized questionnaire. Results. For liquid meal emptying, the time until emptying commenced was 8.1±1.9 and 2.9±0.9 min (mean±SE) in patients and controls, respectively (p=0.02). Thereafter, the first 25% of the meal emptied in 6.8±0.8 and 12.1±1.1 min in patients and controls, respectively (p=0.0005). The overall emptying rate tended to be delayed in patients compared with controls (p=0.06). For the solid meal, a delay in emptying was evident (p=0.02). The patients reported more symptoms from the upper gastrointestinal tract than the controls, but the symptoms were not significantly related to the emptying pathology demonstrated. Conclusions. The present study demonstrates that adult patients with Hirschsprung's disease have an abnormal pattern of gastric emptying, indicating persisting involvement of the upper gastrointestinal tract.

Sleeve Gastrectomy — A Restrictive Procedure?

Diet and surgically-induced weight loss have been shown to lead to alterations in motor and sensory function of the stomach. We investigated the clinical outcome and gastric emptying of solid foods in morbidly obese (MO) patients following sleeve gastrectomy (SG). We studied 23 MO patients [(7 males, 16 females), mean age 38.9 +/- 11.0 years (range 20-64 years), mean weight 135.1 +/- 19.0 kg (range 97-167 kg), mean BMI 47.2 +/- 4.8 kg/m(2) (range 39.6-56.0 kg/m(2))] who each underwent a sleeve gastrectomy (SG) for weight reduction. At the monthly follow-up visits, variations in weight and BMI changes, postoperative meal size and frequency, and presence of gastrointestinal symptoms were recorded. 11 patients underwent scintigraphic measurement of the gastric emptying of a solid meal pre- and 6 months postoperatively. A significant reduction in patients' weight was evidenced at 6 and 12 months postoperatively [98.6 +/- 11.8 kg and 87.0 +/- 10.7 kg respectively (P=0.001)]. BMI decreased to 35.2 +/- 4.3 kg/m(2) at 6 months and to 31.1 +/- 4.5 kg/m(2) at 12 months, respectively (P=0.001). Although meal size was drastically reduced, meal frequency increased postoperatively in 12 patients (52.2%). Only 5 patients (21.8 %) reported occasional vomiting after meals following SG. The gastric emptying half-time (T1/2) accelerated (47.6 +/- 23.2 vs 94.3 +/- 15.4, P<0.01) and the T-lag phase duration decreased (9.5 +/- 2 min vs 19.2 +/- 2 min, P<0.05) post-operatively. The percentage of the meal emptied from the stomach 90 min after consumption increased significantly after SG (75.4 +/- 14.9% vs 49.2 +/- 8.7%, P<0.01). This study indicates that following SG, the stomach empties its contents rapidly into the small intestine and symptoms of vomiting after eating (characteristic of restrictive procedures) are either absent or very mild. Therefore, the term 'restrictive' is possibly ill-advised for this new bariatric operation. It remains for other mechanisms of energy intake reduction, such as intestinal distension and satiety signals through gut hormones to be investigated, to comprehensively explain precisely how this 'food limiting' procedure results in weight loss.

Validity of 13C octanoic acid breath test for measurement of solid meal gastric emptying time in children

Background/Purpose It is important to establish a physiologic range of gastric emptying (GE) in children. Gastric emptying time measured with 99Tc-labeled solid meal (GE Tc) is the gold standard. Large-scale studies with GE Tc are ideal but not feasible because of radiation exposure. The 13C-labeled octanoic acid breath test (GE 13C) does not involve radiation and is suitable for large studies. The aim of this study was to validate GE 13C with GE Tc and to explore whether GE 13C could be used to establish a physiologic range of GE in children. Method Twenty-five healthy children underwent simultaneous GE Tc and GE 13C using a standardized solid test meal. The time taken for the stomach to empty half its content (T½ 13C) and solid lag phase (lag 13C) for GE 13C were computed from the fractional excretion of 13C in expired air. T½ 13C and lag 13C were compared with corresponding values obtained by GE Tc. Result Correlation coefficient between T½ 13C and T½ Tc was 0.69 ( P < .01; r = 0.92 if 3 outliers were omitted). Correlation coefficient between lag 13C and lag Tc was 0.39 ( P < .05). There was good agreement between the methods by the Bland Altman method. Conclusion There is good agreement between GE 13C and GE Tc. GE 13C can be safely used to establish the reference range of GE in healthy children.