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PubMed1988

Diagnostic tests of gastric disorders.

In diagnostic of gastric diseases, fiberendoscopy is today the best procedure. It is superior to radiology with respect to the evaluation of mucosal lesions, the possibility of taking biopsy and therapeutic interventions like hemostatic procedures. Costs for endoscopy are not higher than for radiology. Endoscopy may have a certain morbidity - possible infections via the endoscope - and a mortality less than one per 10.000. Radiology is still useful with respect to the evaluation of motility, the type, form and size of hernias, the presence of extrinsic lesions and certain problems after surgical interventions such as fundoplication. For determination of gastric secretion, the 24-hour ambulatory gastric pH-metry using endoluminal glass electrodes is much more useful than the tests of gastric aspiration. Gastric emptying test and measurement of duodenogastric reflux play a relatively small role in clinical evaluations.

Campylobacter Infections↗

PubMed1984

Prevalence of achlorhydria in a normal population and its relation to serum gastrin.

In a middle-aged group of normal subjects achlorhydria after maximal stimulation with pentagastrin was found in 12 out of 366 males (3%) and 2 out of 198 females (1%); 13 of these 14 (93%) had an elevated serum gastrin, of which nine were more than two times normal. In another 11 persons a moderately elevated serum gastrin - less than two times normal - was found in absence of achlorhydria. At least seven of them had hypochlorhydria. Of 540 persons with a normal serum gastrin one had achlorhydria. Determination of the serum gastrin appeared to be fairly reliable as a method of detecting achlorhydria.

Achlorhydria↗

PubMed1996

Assessment of gastric acidity in intensive care patients: intermittent pH registration cannot replace continuous pH monitoring.

OBJECTIVE: To test the accuracy of colour-scaled indicator papers to measure pH values and to study the correlation between this method of measuring gastric juice pH once daily and 24-h continuous intragastric pH monitoring in intensive care patients. DESIGN: The accuracy of indicator papers was tested in the laboratory using colourless solutions and aspirated gastric juice and was then verified with a laboratory pH meter. Continuous intragastric pH monitoring was performed in mechanically ventilated ICU patients. Percentages of time with a pH value <3.0 and median pH values by 24-h continuous intragastric pH monitoring were compared to pH values measured once daily with indicator paper. SETTING: A mixed ICU. PATIENTS: A total of 150 measurements were taken by continuous pH monitoring in 91 mechanically ventilated ICU patients. MEASUREMENTS AND RESULTS: The correlation between the pH measured with the indicator paper and subsequently verified with a laboratory pH meter in colourless solutions was 0.96 [regression coefficient (RC) 0.98, 95% confidence interval (CI) 0.91-1.05]. Measured in gastric juice it was 0.95 (RC 0.95, 95% CI 0.88-1.01). The correlation between median pH values, determined with 24-h continuous intragastric pH monitoring, and values measured with indicator papers was 0.39 (RC 0.43, 95% CI 0.26-0.59). The mean difference in pH, as determined by the analysis of Bland and Altman], was 0.9 with a SD of 4.7. The correlation between the percentage of time with pH < 3.0, as obtained with continuous registration, and median gastric pH values (also obtained with continuous registration) was -0.94 (RC-0.06, 95% CI-0.06- -0.05); the correlation between the time and gastric pH values (measured with indicator paper) was-0.40 (RC-0.02, 95% CI-0.03- -0.02). CONCLUSION: The colour-scaled indicator paper is an accurate method of measuring pH values, but there is a poor correlation between gastric pH values measured once daily and a total measurement derived from 24-h continuous intragastric pH monitoring. Changes in intragastric pH values cannot be accurately studied when measuring acidity once daily. The influence of various treatment regimens on intragastric acidity in relation to the development of gastric colonization and nosocomial pneumonia should be investigated either with continuous intragastric monitoring or with frequent measurements in aspirated gastric juice.

Adult↗

PubMed1991

[Aluminum absorption in the presence of normal kidney function: the effect of the pH].

Aluminium is a toxic metal of known importance in patients with chronic renal failure on hemodialysis, with a gastrointestinal absorption modulated by several factors including gastric pH which modifies the solubility of Aluminium hydroxide and can increase its absorption. We studied twenty six patients with normal renal function: control (n = 13); presurgery (n = 8); postsurgery (n = 5) by an aluminium hydroxide absorption test (30 mg/kg); serum and urinary aluminium was determined as well as gastric pH and hematologic parameters at different time periods. It was observed that presurgery ulcer patients (pH mean = 2.09) increased serum and urine aluminium levels as well as aluminium/creatinine ratio in urine after the test, opposite to what occurs in the postsurgery group (pH mean = 5.78) in which such parameters were not significantly modified. No differences were found in hematological parameters between the two groups. Our results indicate that acid gastric pH seems to be a factor capable of increasing gastrointestinal absorption of aluminium hydroxide since its solubility and thus its disponibility is increased, and make a point on the risk of a prolonged administration of antacids containing aluminium in patients with normal renal function.

Absorption↗

PubMed1981

[Observations on preoperative restriction of fluid intake in infants (author's transl)].

The problem was investigated whether a reduction to 4 hours of the interval between fluid intake and start of anaesthesia carried increased anaesthetic risks. In 23 infants the residual volume of gastric fluid, its pH and glucose concentration were determined 6 hours after normal feeding and 2 hours and 4 hours after administration of a 10 per cent glucose solution in quantities equivalent to a normal bottle feed. The results showed almost complete gastric emptying 4 hours after administration of a 10 per cent glucose solution.

Anesthesia, General↗

PubMed1994

The effects of preoperative fluids on gastric volume and pH.

The purpose of this study was to determine the effect that a bolus of water ingested 2 hours before induction of anesthesia would have on gastric volume and pH. The results indicated that the gastric volume was not significantly different between the study group and the control group, and the pH was significantly lower in the study group.

Adult↗

PubMed1983

Parietal cell antibodies in relation to basal serum gastrin in a normal population.

Parietal cell antibodies, basal gastric pH and serum gastrin were determined in 544 normal non-achlorhydric subjects. Serum gastrin was significantly higher in subjects with parietal cell antibodies, both in the group with a weakly positive and in that with a strongly positive fluorescence score. The elevated serum gastrin level in subjects with circulating parietal cell antibodies was independent of gastric pH. It is suggested that parietal cell antibodies may interfere with gastrin receptors on the membrane of the parietal cell, thus influencing the feedback mechanism between the secretion of acid and gastrin, and resulting in an increase of the basal serum gastrin level at an unchanged basal gastric pH.

Adult↗

PubMed1988

CA 19-9 determination in gastric juice: role in identifying gastric cancer and high risk patients.

Gastric juice CA 19-9 levels were determined in 23 patients affected by gastric cancer, in 57 patients affected by chronic atrophic gastritis of different severities and in 55 'healthy' controls, undergoing endoscopy for upper gastrointestinal tract symptoms. Increased CA 19-9 levels were documented in chronic atrophic gastritis patients as well as in gastric cancer patients, the difference with respect to controls being statistically significant. However, there was considerable overlap between different groups. In particular, gastric cancer patients had CA 19-9 levels similar to those detected in moderate and severe chronic atrophic gastritis. CA 19-9 correlated with gastric juice pH and CEA concentration. Its values were not influenced by the patients' age or sex. In our opinion CA 19-9 gastric juice determination, although not useful in singling out patients harboring gastric neoplasia, may be used in identifying patients 'at risk' for gastric cancer and who might then be referred for more accurate investigations.

Adult↗

PubMed1985

Omeprazole: a study of its inhibition of gastric pH and oral pharmacokinetics after morning or evening dosage.

Pharmacodynamic and pharmacokinetic studies of omeprazole, a new gastric antisecretory agent, were undertaken in 8 healthy subjects. The drug was administered orally as an encapsulated enteric-coated granulate (40 mg daily at 9 am or 9 pm for 5 days), and its effect on the integrated 24-h gastric pH was determined, together with its apparent bioavailability. The pretreatment 24-h median pH was 1.9 (interquartile range 1.4-2.9). After 5 days of treatment, the median pH had risen to 5.0 (3.7-6.0) (p less than 0.01) with morning dosage and 4.5 (3.0-5.6) (p less than 0.01) with evening dosage. This corresponded to a greater than 99% reduction in 24-h median hydrogen ion activity, with morning dosage having a greater effect (from 9 am to 8 pm) (p less than 0.01) than evening dosage. The relative bioavailability of omeprazole increased twofold from day 1 to day 5 of treatment with morning dosage (p less than 0.02) and threefold with evening dosage (p less than 0.02), suggesting that increased absorption of this acid-labile drug occurs with increasing inhibition of acid secretion. We conclude that this formulation of omeprazole presently being used in clinical trials is a highly potent antisecretory agent in humans, although its optimal effect may not be observed for several days.

Adult↗

PubMed2005

Changes in reducing power profile of gastric juice in patients with active duodenal ulcer.

Reactive oxygen species have been postulated to play a role in the pathogenesis of mucosal GI injury and in peptic ulcer disease (PUD). The low molecular weight antioxidants (LMWA) group plays an important role in the defense mechanism of the GI tract against oxidative damage, and is a major component of the reducing capacity of biological tissues and fluids. We hypothesized that altered gastric LMWA anti oxidative status might play a role in the pathogenesis of upper GI disorders such as PUD and could be evaluated by measuring gastric juice reducing power. The aim of the present study was to determine, by cyclic voltammetry, changes in the overall antioxidant activity of the gastric juice in active duodenal ulcer (DU) obtained during upper endoscopy from patients as compared with normal subjects. The results show that in 28/37 (76%) of the control subjects, gastric juice demonstrated a reducing power of at least two anodic waves indicating at least two different LMWA groups. Three or more anodic waves were recorded in 12 normal subject (32%). In contrast, 16/25 (64%) of gastric juice samples obtained from active DU patients exhibited only one anodic wave usually at a high potential (>900 mV). These results imply that gastric juice normally possesses a reducing power profile that can be determined by cyclic voltammetry. This profile is significantly changed in untreated DU disease. These changes in active DU may indicate decreased gastric antioxidant activity reflecting reduced mucosal protection that leading to increased susceptibility of the gastro-duodenum to injury.

Adult↗

PubMed1991

Effect of acute ingestion of tobacco on gastric mucosa. An endoscopic study.

One hundred patients with non ulcer dyspepsia with history of chronic tobacco chewing were examined endoscopically to assess the effect of tobacco ingestion on the gastric mucosa. Gastric erosions were seen in 20 patients in the fasting state. The remaining 80 patients in whom gastroscopy did not reveal erosions were subjected to repeat gastroscopy after tobacco ingestion. In 40 patients, endoscopy was repeated 30 minutes after 200 mg of tobacco ingestion (Group I) and in another 40 patients endoscopy was repeated 1 hour after 400 mg of tobacco ingestion (Group II). Eleven patients (27.5%) in Group I and 19 (47.5%) in Group II developed gastric erosions. Erosions were observed mainly along the lesser curvature, and in the fundus and the body of stomach. Gastric pH, determined after tobacco ingestion, was 2.4 +/- 0.43 in patients with erosions and 3.0 +/- 0.67 in patients without erosions. It is concluded that tobacco ingestion produces dose-dependent damage to the gastric mucosa as seen on endoscopy. Hence, history of tobacco ingestion should always be asked for in patients with gastric erosions.

Gastric Acidity Determination↗

PubMed1982

[Secretory function indices of the stomach in peptic ulcer of varying severity].

The parameters of acidity, concentration and debit of pepsin, partial secretion, alkaline-acidic and acidic-peptic coefficients were determined in patients with the ulcerous disease. A reliable increase in the secretion on the empty stomach was found in severe course of the ulcerous disease. The main factors of aggression (debit of the acid, concentration and debit of pepsin( tend to increase in more severe course of the disease. The data obtained may be used for solving the question of the timely operative treatment.

Duodenal Ulcer↗

PubMed1987

A new method for measurement of the electrical potential difference across the stomach wall. Clinical evaluation of the gastric mucosal integrity.

PD, the electrical potential difference across the gastric mucosa, is a variable used frequently in experimental studies. Existing methods for PD measurements are, however, unstable, and variations in the pH of the gastric juice causes liquid junction potentials between gastric juice and the PD measuring probe. A new PD measuring system has been developed with high stability, easy handling, and correction for the liquid junction potentials. PD was measured between a stomach microelectrode and an intravenous reference electrode connected to a millivoltmeter. pH was measured by an intragastric microelectrode. The liquid junction potential was calculated by using the pH measured in the gastric juice and the Henderson equation and was then subtracted from the measured PD to provide a better approximation of the PD across the mucosa. The liquid junction potential calculated as stated above correlated with the liquid junction potential calculated from precise ion determinations made in gastric juice samples (y = x; r = 0.92; p less than 0.05). The reliability of the PD measuring system was tested in vitro and in vivo and was satisfactory. In conclusion, a new, reliable, and easily applied method for gastric PD measurements corrected for the liquid junction potential between gastric juice and the PD measuring probe has been developed.

Action Potentials↗

PubMed1995

Mediation by CCKB receptors of the CCK-evoked hyperaemia in rat gastric mucosa.

1. Cholecystokinin octapeptide (CCK-8) and gastrin-17 augment gastric mucosal blood flow in the rat. The present study examined whether the gastric vasodilator effect of these peptides is mediated by CCKA or CCKB receptors. 2. Intravenous injection of CAM-1481 (1 mg kg-1), a dipeptoid antagonist of CCKA receptors, or CAM-1028, a dipeptoid CCKB receptor antagonist (1 mg kg-1), had no effect on basal gastric mucosal blood flow as determined by the clearance of hydrogen in urethane-anaesthetized rats. 3. Intravenous infusion of CCK-8 or gastrin-17 (8-200 pmol min-1) increased gastric mucosal blood flow in a dose-dependent fashion. The CCKB receptor antagonist, CAM-1028, significantly attenuated the hyperaemic response to CCK-8 and gastrin-17 whereas the CCKA receptor antagonist, CAM-1481, did not antagonize CCK-8 but caused a slight attenuation of the vasodilator response to gastrin-17. 4. The selectivity of the two antagonists was proved by the findings that CAM-1028, but not CAM-1481, inhibited gastric acid secretion evoked by CCK-8 or gastrin-17 (CCKB receptor assay) while CAM-1481, but not CAM-1028, inhibited the CCK-8-induced contraction of guinea-pig isolated gall bladder strips (CCKA receptor assay). 5. These data show that the actions of CCK-8 and gastrin-17 to increase mucosal blood flow in the rat stomach are primarily mediated by CCKB receptors.

Animals↗

PubMed1993

Intracerebroventricular neuropeptide Y increases gastric and pancreatic secretion in the dog.

BACKGROUND: Neuropeptide Y (NPY), a centrally located neurotransmitter, is known to increase appetite in fasted and satiated animals. In addition to evaluating NPY's effect on eating behavior, this study was intended to determine whether intracerebroventricular (ICV) NPY would have an effect on canine gastric and pancreatic secretion. METHODS: Four dogs were prepared with cerebroventricular guides and gastric and pancreatic fistulas. ICV and intravenous NPY was administered during intragastric titration of a glucose and peptone meal. During this study, gastric and pancreatic secretion was measured, as well as insulin levels and pancreatic polypeptide (PP). An additional set of four dogs were prepared with esophageal fistulas and cerebroventricular guides, and the effect of ICV NPY on sham feeding was studied. RESULTS: ICV NPY significantly increased sham feeding, meal-stimulated gastric and pancreatic secretion, basal gastric acid, pancreatic bicarbonate, insulin levels, and PP. Vagotomy blocked the effect of ICV NPY on gastric acid secretion in a urethane-anesthetized rat model with acute gastric fistula. CONCLUSIONS: ICV NPY increased sham feeding, gastric and pancreatic secretion, insulin levels, and PP in the dogs. NPY's effect on gastric secretion was blocked by vagotomy in a rat model. NPY should be considered a candidate mediator of cephalic phase secretion.

Analysis of Variance↗

PubMed1981

Progression of changes in gastric emptying of hypertonic liquids after proximal gastric vagotomy. An experimental study.

Gastric emptying rates of hypertonic (10%) dextrose liquid meals were studied in five dogs before, and 3, 6, and 12 months after proximal gastric vagotomy (PGV) without drainage. The purpose of this study was to determine if operation-related changes in emptying rates normalized or became more disparate during the year after PGV. An increased rate of emptying during the first 5 min after ingestion was seen at 3 months after PGV, which significantly increased (P less than 0.025) after 6 and 12 months. The remainder of the meal after PGV emptied at a regulated expotential rate unchanged throughout the postoperative year from its preoperative rate. Total volumes of gastric aspirate at four intervals after meal ingestion did not significantly change across the four test periods in respect to endogenous secretion or pH acidity.

Animals↗

PubMed1987

[Determination of N-nitroso compounds in the gastric juice for evaluation of the individual nitrosating capacity of the body].

The article deals with a comparison of the results of human body nitrosating ability determination by two methods: (a) nitroso compound (NC) assay in diurnal urine after oral administration of its precursors, and (b) assay of the same in gastric juice after in vitro addition of precursors. The data for the first part of the investigation were obtained from the literature, and for the second one--from the experiments by the authors. Both studies used essentially identical groups of patients, primarily those suffering gastrointestinal pathology. Since the results matched to a considerable degree, it was inferred that (1) gastric juice is a factor of body nitrosating ability, and (2) in vitro determinations of said ability in gastric juice are fully justified. Moreover, the latter procedure is sometimes more practicable, particularly, in view of the marked relationship between nitrosating ability, and, especially, the efficacy of inhibitors of NC endogenous synthesis, on the one hand, and the individual characteristics of the body, on the other.

Aminopyrine↗

PubMed1978

Inhibitory role of the distal small intestine on the gastric secretory response to meals in man.

The role of the distal small intestine on postprandial gastric function was determined in 6 healthy volunteers by diverting chyme from the intestine at a site 100 cm distal to the ligament of Treitz and comparing the results with those observed in the same subjects when chyme was exposed to the entire gut. Diversion of chyme increased the gastric secretory response, which suggests that the distal small intestine has an inhibitory role in postprandial gastric secretion.

Adult↗