Neural gastrointestinal electrical stimulation (NGES) induces sequential contractions and enhances emptying in acute canine gastric and colonic models. This study was set to determine (i) the effect ...of NGES in a chronic canine model of delayed colonic transit and (ii) possible mechanism of action. Four pairs of electrodes were implanted in the distal colon of nine mongrel dogs. Delayed colonic transit was induced by diphenoxylate/atropine and alosetron. Transit was fluoroscopically determined by the rate of evacuation of radiopaque markers, and was tested twice in each dog, in random order, on and off stimulation. Two stimulation sequences, separated by 1 min, were delivered twice a day via exteriorized electrodes. Colonic manometry during stimulation was performed before and after intravenous (i.v.) injection of 1 mg of atropine. Complete evacuation of all markers was significantly shortened by NGES, from 4 days to 2 days, interquartile range 3–4 days vs 2–3 days, respectively, P = 0.016. NGES induced strong sequential contractions that were significantly diminished by atropine: 190.0 ± 14.0 mmHg vs 48.7 ± 19.4 mmHg, respectively (P < 0.001). NGES induces strong sequential colonic contractions and significantly accelerates movement of content in a canine model of delayed colonic transit. The effect is atropine sensitive.
In high-resolution manometry lower esophageal sphincter pressure (LESP) is measured relative to intragastric pressure, however Gastric Marker™ (GM) location used to determine resting LESP is not well ...established with hiatal hernia (HH). We test the hypothesis that measured resting LESP varies with HH based on GM location.
Subjects with HH ≥ 2 cm were included. The eSleeve™ was adjusted to span only the LES, excluding the crural diaphragm (CD). Resting LESP was determined by placing the GM below and above the CD (in the position yielding the highest resting LESP). Resting pressure across the lower esophageal sphincter (LES) to CD and pressure in the HH relative to subdiaphragmatic intragastric pressure were also measured.
HH ≥ 2 cm was present in 98 patients (mean length 2.7 cm). LESP decreased when GM was moved from below the CD into the HH: respiratory minimum LESP 7.5 ± 1.1 to 3.6 ± 0.9 mmHg; P < 0.001, mean LESP 17.7 ± 1.3 to 13.7 ± 1.1 mmHg; P < 0.001. When the eSleeve encompassed the LES and CD, the respiratory minimum pressure was 12.2 ± 0.9 mmHg and mean pressure was 23.9 ± 1.0 mmHg pressure (P < 0.001 for both). Pressure in the hernia pouch was greater than intragastric pressure: respiratory minimum 3.0 ± 0.7 mmHg and mean 9.0 ± 0.8 mmHg (P < 0.001 for both). pH studies showed a trend toward an association between abnormal distal esophagus acid exposure and lower resting LESP.
GM placement in the HH produces lower resting LESPs. This may provide a more physiologic representation of LESP in HH.
Gastric electrical stimulation (GES) improves symptoms in patients with gastroparesis. However, the underlying mechanisms remain unclear. To determine if GES at proximal and distal stomach could ...affect the biomechanical properties of the stomach, thus contributing to the beneficial effect of GES. Four pairs of electrodes were implanted along the greater curvature of the stomach in seven dogs. Gastric tone and compliance was assessed with a barostat. Measurements were obtained randomly during control and proximal and distal stimulation (4 mA, 375 ms and 6/18 cpm). Data as mean or median (25–75th percentiles). Gastric compliance was not affected by proximal and distal GES. Gastric tone was significantly reduced during proximal GES: 82.0 (66.8, 89.1) mL vs control 49.7 (39.6,75.9) mL at 6 cpm (P = 0.016), and 90.6 (54.5, 117.9) mL vs control 62.8 (39.6, 75.9) mL at 18 cpm (P = 0.031). Tone was not affected by distal GES at 6 cpm: 95.8 (46.3, 106.7) mL vs control 75.2 (49.7, 86.1) mL (P = 0.47) and at 18 cpm: 80.4 (38.1, 170.3) mL vs control 62.8 (44.6, 156.3) mL (P = 0.44). Proximal GES induces gastric relaxation. This effect, if seen also in humans, may explain, in part, the symptomatic improvement associated with GES therapy in patients with gastroparesis.
Background
A simplified report of gastric retention values at select times is now recommended for scintigraphic gastric emptying test (GET).
Aims
The purpose of this study was to assess correlation ...between severity of gastroparetic symptoms and all variables of GET, compared to select variables in clinical use.
Methods
This was a prospective study of patients referred for scintigraphic GET. The Gastroparesis Cardinal Symptom Index questionnaire was obtained prior to the scintigraphy. Variables determined were lag time, half emptying time (T1/2), retention at 30 min, 1, 2 and 4 h. Statistical analysis was by Spearman rank correlation and Wilcoxon rank test with a significance set at
p
≤ 0.05.
Results
Seven hundred seventeen patients had GET from 03/09 to 03/11. Results are from 325 patients who did not take medications known to affect GET were analyzed (64.9 % females, mean age 47 ± 18.9 years, 21.8 % diabetics, 78.2 % non-diabetic, of which 7.6 % were post-surgical, primarily post-fundoplication). Combined gastric retention at 2 and 4 h detected delayed GET in 83.5 % non-diabetics and 76.6 % of diabetics. Rapid GET was present in 11 % of patients at 30 min and 4 % at 1 h. Significant positive correlation was observed between nausea, vomiting, loss of appetite and variables of GET, but not with the half-time of emptying (T1/2). Bloating negatively correlated with retention at 2 h. There was no association between duration of symptoms and GET variables.
Conclusions
Gastroparetic symptoms correlate with different retention times of GET, but not with T1/2. However, symptoms poorly distinguish between categories of gastroparesis or status of gastric emptying. Delayed GE is best detected by 2 and 4 h retention times, while 30 min and 1 h retention times detect rapid GE.
Saliva and esophageal protection Kongara, K R; Soffer, E E
The American journal of gastroenterology,
06/1999, Letnik:
94, Številka:
6
Journal Article
Recenzirano
There has been much interest in recent years in the potential protective role of saliva in the esophagus. Variables such as salivary volume and neutralizing capacity have been studied both during ...basal conditions and in response to esophageal acid exposure, in healthy subjects and in patients with esophagitis. In addition to its known neutralizing capacity, saliva also contains growth factors. These polypeptides (of which epidermal growth factor has been studied most) have cytoprotective and healing properties in various segments of the gastrointestinal tract. Therefore, a deficiency in one or more of these growth factors might be a contributing factor in the development of gastroesophageal reflux disease (GERD) or its complication, such as Barrett's metaplasia. However, human studies have produced contradictory results regarding salivary growth factor deficiency in such patients. Current methods of investigation make it difficult to assess the importance of saliva in GERD. This may be due in part to the multifactorial nature of the disease and the difficulty in long-term, selective manipulation of salivary function in humans. Given the present data in the literature, it is therefore unknown if saliva plays an important role in esophageal protection.
Functional abdominal pain, including the irritable bowel syndrome, is more common in females. Our aim was to determine if differences in motility or biomechanical properties of the colon could ...account for this gender difference. In 18 healthy subjects (nine males), a catheter assembly incorporating a balloon and perfused side holes, connected to a barostat, was positioned in the left colon. The system was used to determine compliance, sensation in response to phasic balloon distension, and changes in motor activity and tone in response to a meal. There was no significant difference in any of these variables between males and females. We conclude that there is no gender difference in colonic motor function or sensation to balloon distension. The increased prevalence of irritable bowel syndrome in females may be related to psychosocial factors rather than differences in colonic motor function.
A study supports the concept that microscopic colitis is a disorder affecting the colon throughout its length. Consequently, flexible sigmoidoscopy with biopsies taken from various segments of the ...left colon will detect almost all patients with microscopic colitis and may preclude the need for colonoscopy.
It is important for primary care physicians to take fecal incontinence seriously and not dismiss it as a normal part of aging. Elderly patients may be reluctant to admit fecal incontinence, so ...clinicians need to ask about it. Two of the most common causes are fecal impaction (especially in nursing home patients) and rectosphincter dysfunction in people with diabetes.
Acupuncture has been used as a therapy for various gastrointestinal disorders, including irritable bowel syndrome (IBS). However, there is scant information on the effect of acupuncture on gut ...physiology. The purpose of this study was to evaluate the effect of transcutaneous electrical acustimulation (TEAS) on rectal tone, compliance and perception in IBS patients.
Seven patients with diarrhea-predominant IBS were studied during control, sham stimulation and acupoints (ST36 and P6) stimulation periods. Rectal tone, compliance and perception to rectal balloon distension were assessed with a barostat apparatus.
Acustimulation at ST36 and P6, but not sham stimulation, significantly increased the threshold of rectal sensation of gas, desire to defecate and pain, as compared to control period. However, rectal tone and compliance were not significantly affected during TEAS.
TEAS, at the above acupoints, can reduce rectal sensitivity in IBS patients. The effect is not modulated by changes in rectal biomechanics.
Background:
Irritable pouch syndrome (IPS) is a functional disorder in patients with ileal pouch–anal anastomosis (IPAA), which presents with symptoms in the absence of structural abnormalities of ...the pouch. Thus, it resembles other functional disorders, such as irritable bowel syndrome characterized by visceral hypersensitivity in the presence of normal rectal biomechanics. The aim was to assess pouch biomechanics and perception of balloon distension in different groups of subjects with IPAA and to correlate the findings with clinical features.
Methods:
Pouch tone, compliance, and sensation to balloon distension were measured in 18 patients with IPS, 11 patients with active pouch inflammation (pouchitis or Crohn's disease of the pouch), and 12 asymptomatic subjects with normal pouches. All patients were recruited from a subspecialty Pouchitis Clinic.
Results:
Scores of sensation of gas, urge to defecate, and pain measured by visual analog scales at various distension pressures were significantly higher in IPS than pouchitis and normal pouch patients. Pouch tone was comparable among the groups and compliance was reduced in the pouchitis group. The visual analog scale showed a trend of correlation with the Pouchitis Disease Activity Index symptom scores in IPS.
Conclusions:
IPS, like other gut functional disorders, is characterized by visceral hypersensitivity, with normal pouch biomechanics. (Inflamm Bowel Dis 2011)
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