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[Effect of meat pâtés of different composition on gastric secretory function].

Experiments on 4 dogs with isolated Pavlovian pouches were made to study the action on gastric secretion of a new type of a beef paté in which 20% of basic raw material was replaced by precipitated blood plasma proteins (a sample under study) and of a beef paté of a conventional composition (a control sample). Both paté samples were found to provoke a characteristic gastric juice secretion which strongly differed from the secretion pattern during beef feeding. This was determined by the presence in the patés of a significant amount of fat and by the homogenized nature of the paté mass. Gastric juice thus obtained was marked by a slightly decreased acidity, low content of hydrochloric acid pH 1.7-2.6, and moderate pepsin concentration. Replacement in beef paté of 20% of basic raw material by precipitated blood plasma proteins did not provoke any changes in gastric secretion as compared to that seen during intake of patés of a conventional composition.

Animals↗
PubMed1995

Combined measurements of blood lactate concentrations and gastric intramucosal pH in patients with severe sepsis.

OBJECTIVE: To compare the prognostic value of blood lactate concentrations, gastric intramucosal pH, and their combination in patients with severe sepsis. DESIGN: Prospective, noninterventional study. SETTING: Medical/surgical intensive care unit of a university hospital. PATIENTS: The study included 35 consecutive patients (44 to 82 yrs) with severe sepsis as defined by fever or hypothermia (rectal temperature > 38.3 degrees or < 35.5 degrees C), tachycardia (heart rate > 100 beats/min), tachypnea (respiratory rate > 20 breaths/min) or mechanical ventilation, abnormal white blood cell count (> 10 or < 6 x 10(3) cells/mm3), hypotension (systolic arterial pressure < 90 mm Hg), and evidence of organ dysfunction (oliguria or deterioration of mental status). INTERVENTIONS: Arterial lactate concentration and intramucosal pH were measured at the time of study entry, and at 4 and 24 hrs later. Hemodynamic data and oxygen-derived variables were determined at the time of study entry and 24 hrs later. Arterial blood and balloon saline gases were also determined to obtain the pH gap (arterial pH-intramucosal pH) and the PCO2 gap (intramural PCO2-PaCO2). MEASUREMENTS AND MAIN RESULTS: Of the 35 patients, 19 survived the intensive care unit stay. At the time of study admission, 23 (66%) patients had an increased lactate concentration (> 2 mEq/L) and 26 (74%) had a low intramucosal pH (< 7.32). Initially, there were no significant differences in blood lactate concentrations between nonsurvivors and survivors (3.2 +/- 1.5 vs. 2.8 +/- 2.3 mEq/L). Lactate concentrations remained high in nonsurvivors and progressively decreased in survivors (4 hrs: 3.3 +/- 1.1 mEq/L in nonsurvivors vs. 2.2 +/- 0.9 mEq/L in survivors [p < .01]; 24 hrs: 3.5 +/- 2.0 mEq/L in nonsurvivors vs. 1.9 +/- 1.1 mEq/L in survivors [p < .05]). Intramucosal pH was lower in the nonsurvivors than in the survivors initially (7.19 +/- 0.15 in nonsurvivors vs. 7.30 +/- 0.14 in survivors [p < .05]), at 4 hrs (7.18 +/- 0.17 in nonsurvivors vs. 7.29 +/- 0.13 in survivors [p = .06]), and at 24 hrs (7.19 +/- 0.31 in nonsurvivors vs. 7.30 +/- 0.17 in survivors [p < .05]). Of the 23 patients with initially high lactate concentrations, 12 (60%) of the 20 patients with low intramucosal pH died, as compared with one (33%) of the three patients with normal intramucosal pH (p = .052). Of the 14 patients with persistently high lactate concentrations at 24 hrs, all nine (100%) patients with low intramucosal pH, but only two (40%) of five patients with normal intramucosal pH died (p < .001). No significant relationship was found between lactate or intramucosal pH and oxygen-derived variables. Intramucosal pH correlated better with gastric intramural PCO2 (r2 = .58) than with arterial bicarbonate or base deficit/excess. Intramural PCO2 was a more specific predictor of mortality than intramucosal pH. When compared with patients with normal lactate concentrations, those patients with high lactate concentrations had a higher pH gap (0.22 +/- 0.22 vs. 0.07 +/- 0.13 [p < .01]) and PCO2 gap [21.0 +/- 33.9 vs. 1.8 +/- 9.8 torr [2.79 +/- 4.5 vs. 0.24 +/- 1.34 kPa]; p < .01). CONCLUSIONS: Both lactate concentrations and intramucosal pH represent reliable prognostic indicators in severe sepsis, and their combination improves the prognostic assessment in these patients. Both variables are better prognostic indicators than oxygen-derived variables. Intramural PCO2 appears to be a more specific variable than intramucosal pH, which partially reflects systemic metabolic acidosis. Combined determinations of blood lactate concentrations and intramucosal pH or intramural PCO2 may help to predict outcome from severe sepsis.

APACHE↗
PubMed1994

[Assessing the pH value of gastric mucosa with tonometry--general practice and potential clinical value].

The significance of the gastrointestinal region in the genesis and course of sepsis makes the monitoring of this region a fundamental importance in critical ill patients. The low-invasive assessment of gastric mucosal pH (pHi) seems to be able to detect a disturbed tissue oxygenation in the splanchnic region at an early stage. Animal studies have shown that there is a good correlation between pHi and directly measured pH. Splanchnic tissue hypoxia, induced in an experimental setting, is detectable by the pHi method. It has been shown in clinical studies that the patients' outcome depends on the first pHi, measured on admission to the ICU. An initial study has shown that patients with a pHi in the normal range on admission to the ICU had a better outcome if they were treated by a pHi-value orientated therapy. Nevertheless, some questions remain: There are problems with the practical use of this method, and it is unclear whether the pHi is really a marker for the whole splanchnic area. Further studies are required to determine the status of pHi in the clinical setting.

Animals↗
PubMed1997

Twenty-four-hour intragastric acidity and plasma gastrin during 3-month treatment with omeprazole in healthy subjects.

BACKGROUND: Prolonged treatment with omeprazole 20 or 40 mg/day is sometimes required, especially for severe oesophagitis. However, information about long-term effects on intragastric acidity and plasma gastrin response with such drug regimens is scarce. METHODS: Sixteen healthy subjects (11 men, 5 women, mean age 29 years) randomly received either 20 or 40 mg of omeprazole once daily (at 08.00 h) for 3 months. Gastric pH was recorded every 6 s for 24 h from noon to noon under standardized conditions, and blood samples were collected hourly in order to determine the 24-h plasma gastrin response on day 0 (pre-entry), day 7, day 28 and day 90. RESULTS: From day 0 to day 7, 24-h median pH increased from 1.7 to 4.6 and mean percentage of time at pH < 4 decreased from 89% to 35% with omeprazole 20 mg. Respective values with omeprazole 40 mg were 1.9 to 4.3, and 89% to 34%. Inhibition of gastric acidity remained unchanged during the 3 months of treatment. Despite similar effects on the basis of 24-h analysis, the decrease in daytime acidity was slightly higher with omeprazole 40 mg than with omeprazole 20 mg. Twenty-four-hour integrated plasma gastrin significantly increased with both drug regimens between day 0 and day 7 (P < 0.01), and between day 7 and day 28 (P < 0.01) with omeprazole 40 mg; there was no significant increase between day 28 and day 90 with either of the drug regimens. CONCLUSION: Omeprazole 20 and 40 mg/day provides long-term stable acid suppression with a progressive increase in gastrin response, stabilizing after 2 months of treatment.

Adult↗
PubMed2001

Duration of effect of lansoprazole on gastric pH and acid secretion in normal male volunteers.

AIM: A double-blind, placebo-controlled study to assess the duration of effect of lansoprazole 30 mg o.m. on intragastric pH, acid secretion, gastrin levels, the potential for rebound acidity, and the relationship between gastric acid and drug pharmacokinetic parameters. METHODS: Sixteen subjects were treated with lansoprazole 30 mg daily or placebo for 14 days, followed by a 7-day post-dosing period and a post-study evaluation on day 28. Ambulatory 24-h pH was recorded and pentagastrin-stimulated acid secretion measured. Plasma kinetics of lansoprazole were determined. RESULTS: Mean intragastric pH in the lansoprazole group increased significantly (P < 0.05) from baseline to day 14 compared to placebo. After cessation of treatment, secretory activity, as measured by intragastric pH, basal acid output and stimulated acid output, returned to baseline in 2 to 4 days without any overshoot, indicating the absence of acid rebound. Lansoprazole's terminal disposition half-life was 1.11 h. Mean pH and serum gastrin returned to baseline with half-lives of 22 and 19 h, respectively. CONCLUSIONS: Lansoprazole 30 mg daily significantly increases mean intragastric pH without producing acid rebound. Regeneration of acid production depends primarily on de novo synthesis of the acid pump.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed2004

Dietary protein precipitation properties have effects on gastric emptying in healthy volunteers.

BACKGROUND & AIMS: Strategies that reduce the size of particles in the stomach accelerate gastric emptying. Partial dephosphorylation of casein reduces the size of protein precipitates (curds) in acid conditions and facilitates peptic digestion. We hypothesized that changing the precipitation properties of casein by partial dephosphorylation would accelerate gastric emptying. METHODS: Eight healthy male volunteers entered a prospective, double blind, randomized study with crossover design. Gastric emptying of milk based formula containing either unmodified or dephosphorylated casein was assessed by scintigraphy. Gastric pH measurements were acquired concurrently. RESULTS: A trend to faster gastric emptying was observed for the unmodified preparation, with lower median half time (unmodified 133; dephosphorylated 214 min, P = 0.09) and area under the curve (unmodified 8425 min%; dephosphorylated 9135 min%, P = 0.08). A positive correlation was found between half time for the dephosphorylated preparation and the treatment effect (r2 = 0.81, P < 0.02). Gastric pH was unaffected. CONCLUSIONS: The study hypothesis was rejected; indeed gastric emptying tended to be faster for the unmodified than the dephosphorylated protein. This effect was more pronounced in subjects with slow gastric emptying on the dephosphorylated preparation. Properties other than the size of protein precipitates determine the rate of gastric emptying for milk based formula.

Adult↗
PubMed1997

Protection by amylin of gastric erosions induced by indomethacin or ethanol in rats.

1. The effect of amylin on gastric ulcers induced by oral administration of indomethacin (Indo, 20 mg kg-1 at a dosing volume of 5 ml) or ethanol 50% (EtOH, 1 ml/rat) was investigated in conscious rats. 2. Amylin given intracerebroventricularly (0.22, 0.66 and 2.2 micrograms/rat, i.c.v.) demonstrated a dose-dependent cytoprotective effect against both Indo and EtOH-induced ulcers. In contrast, amylin, given subcutaneously at doses effective in inhibiting acid gastric secretion (2.5, 10 and 40 micrograms kg-1, s.c.), did not show any cytoprotective effect. 3. The interaction between amylin and endogenous nitric oxide (NO) in the maintenance of gastric mucosal integrity was investigated by pretreating the rats with a selective inhibitor of NO-synthesis, NG-nitro-L-arginine methyl ester (L-NAME, 25 and 70 mg kg-1, s.c.). Administration of L-NAME to rats did not significantly increase the degree of the Indo-induced ulcer index and was not able to remove the protective effect of amylin on Indo-induced ulcers, thus excluding a role for endogenous NO in mediating the protective effect of this peptide. 4. To determine whether the cytoprotective effect of amylin was mediated by endogenous prostaglandins, we studied the effect of amylin (2.2 micrograms/rat, i.c.v.) on EtOH- induced ulcers in rats pretreated with Indo (10 mg kg-1, s.c.) to inhibit prostanoid biosynthesis; Indo was injected 30 min before amylin and EtOH after a further 30 min. Pretreatment with Indo did not significantly increase the ulcer index induced by EtOH but counteracted the ability of amylin to prevent the ulcer formation. 5. These findings suggest that amylin exerts a gastroprotective activity that is not strictly related to inhibition of acid gastric secretion and can be partly explained through a prostaglandin-dependent mechanism mediated by receptors for the peptide in the brain. Amylin might be considered as a new brain-gut peptide.

Amyloid↗
PubMed1986

Effect of various types of dietary fibre on gastric emptying in growing pigs.

1. Five pigs initially of 40-50 kg live weight were fitted with simple gastric cannulas which permitted complete evacuation and sampling of gastric digesta once daily. 2. The effects of addition of four types of dietary fibre (wheat bran (WB; 40 g/kg), sodium carboxymethylcellulose (CMC; 40 g/kg), high-methoxy citrus pectin (Pe; 40 g/kg) and granulated guar gum (G; 40 g/kg] on gastric emptying of a semi-purified diet during 4 h following a meal were measured. 3. Each of the test diets and the control diet (C) were given to each pig for 1 week using a 5 x 5 Latin-square arrangement. Digesta were collected before and 0.5, 1, 2 or 4 h after feeding on the last 5 d of each week. 4. The mean gastric pH was not significantly affected by diet except 2 h after feeding (CMC higher than C) and 4 h (Pe, G and CMC higher than C). 5. Compared with diet C, the rate of gastric emptying of digesta was significantly slower for diet G, 1, 2 and 4 h after feeding, and 2 and 4 h after feeding for diet CMC. 6. The rates of gastric emptying of digesta components were not significantly reduced by dietary fibre except for dry matter (DM) (diet CMC 2 h and diet B 4 h after feeding), total nitrogen (TN) (diet G 2 h after feeding) and total glucose (diet Pe 2 h after feeding). 7. There were no significant effects of diet on trichloroacetic-acid-soluble N:TN. 8. When gastric emptying was expressed in terms of half-time (T50) values, significant increases (compared with diet C) were found for digesta (diets G and CMC), DM (diet WB) and TN (diet G). 9. The apparent viscosity of the gastric digesta was significantly higher when diets Pe, G, and CMC were given than diets C or WB. Diets Pe and CMC were very viscous in the meal before ingestion, but diet G was not; its high viscosity developed after it had reached the stomach. 10. It is concluded that although those types of dietary fibre which increased meal or gastric viscosity reduced the rate of gastric emptying of digesta, this effect was confined to the liquid phase, because DM, total glucose and TN emptying were largely unaffected. The hypothesis that a reduced rate of gastric emptying may be an important determinant of the decreased rates of glucose absorption observed when such sources of dietary fibre are eaten is not supported by the results presented.

Animals↗
PubMed1996

Gastric intramucosal pH predicts outcome after surgery for ruptured abdominal aortic aneurysm.

OBJECTIVE: The mortality associated with repair of ruptured abdominal aortic aneurysms (RAAA) remains obstinately high and many deaths result from multiple organ failure which is likely to be related to splanchnic ischaemia. The aim of this study is to investigate the importance of splanchnic ischaemia in determining outcome from RAAA by comparing gastric intramucosal pH with other methods of assessing the adequacy of splanchnic oxygenation. DESIGN AND SETTING: Prospective cohort of patients following surgery for RAAA admitted to the Intensive Care Unit of Guy's Hospital, London. OUTCOME MEASURES: Gastric intramucosal pH (pHim) and global haemodynamic, oxygen transport and metabolic variables were measured on admission, at 12 h and at 24 h after admission. Results were compared between survivors and non-survivors and Receiver Operating Characteristic (ROC) curves were constructed to assess the ability of each measurement to predict outcome. RESULTS: The median 24 h APACHE II was 18 and the ICU mortality 45.5%. Gastric pHim was significantly higher in survivors than non-survivors at 24 h (7.42 vs. 7.24, p < 0.01). In survivors who had a low intramucosal pH (pHim) on admission there was a significant improvement over the first 24 h (7.26 to 7.40, p < 0.05), whereas in patients who subsequently died, and had a normal pHim on admission, there was a significant fall in pHim (7.35 to 7.16, p < 0.05). ROC curves showed that gastric pHim was the most sensitive measurement for predicting outcome in these patients. CONCLUSIONS: Gastric intramucosal pH is the most reliable indicator of adequacy of tissue oxygenation in patients with RAAA, suggesting that splanchnic ischaemia may have played an important role in determining survival.

Aged↗
PubMed1982

Evaluation of various techniques to monitor intragastric pH.

Recent reports emphasized the importance of maintenance of a high intragastric pH to prevent gastric mucosal bleeding in acutely ill patients. In this study gastric fluid pH determinations were compared with determinations obtained using an intragastric pH electrode. There was poor correlation between pH determinations obtained by a bare intragastric electrode in contact with the mucosa and pH determinations on fluid aspirated from the stomach. During cimetidine administration mucosal and fluid determinations correlated well, whereas during antacid administrations correlated well, whereas during antacid administration mucosal pH was significantly lower than gastric fluid pH. These results suggest that during antacid administration pH determinations on gastric contents with pH paper may not accurately reflect the pH at the mucosal surface.

Antacids↗