The quantification in human gastric juice of duodenogastric reflux by sodium output and by bile-labelling using indocyanine green

Detection of duodenal fluid in the oesophagus with a sodium ion selective electrode

The assessment of duodeno-oesophageal reflux is difficult as, until recently, no technique has been readily available for continuous ambulatory monitoring. A sodium ion selective electrode placed in the stomach has been previously shown to detect duodenogastric reflux by using sodium as a marker. This relies on the difference in sodium concentration between gastric (5-60 mmol/L) and duodenal, biliary and pancreatic (150 mmol/L) fluids. In this pilot study to assess the efficacy of the electrode in the distal oesophagus, eight subjects without symptomatic gastro-oesophageal reflux and eight subjects with known duodenogastric reflux were studied. Thirty millilitre volumes of varying sodium solutions (40, 80, 100 and 140 mmol/L) were swallowed to assess the response of the electrode to sodium ions. In both groups, this revealed a constant and reproducible rise in response with increasing concentration (P < 0.0001). The stomachs of subjects with duodenogastric reflux were aspirated via a nasogastric tube to obtain 12 different samples of gastric fluid. This was assayed for sodium and bile acid concentration. The fluid was then reinfused as a 30 mL bolus into the oesophagus through a tube to simulate oesophageal reflux. A rise equivalent to 40-72 mmol/L Na+ was recorded by the electrode in response to samples that contained 58-81 mmol/L Na+ and 0.4-16 mmol/L bile acids, recorded by quantitative analysis, and a response of up to 20 mmol/L Na+ was recorded by the electrode to sodium concentrations < 49 mmol/L and bile acid concentrations of 0.005-0.6 mmol/L. The response was appropriate to the assayed bile acid concentration in all but one sample. The sodium ion selective electrode responds to bile containing fluids introduced into the oesophagus. Further investigation is warranted to determine its ability to measure duodeno-oesophageal reflux continuously.

Gastric outlet loss and enterogastric reflux after gastrectomy

The relationship of gastric secretion in response to a single injection of insulin and in response to a histamine infusion, before and after partial gastrectomy, was analysed in 58 patients. The aspirated gastric juice was corrected for gastric outlet loss and enterogastric reflux. Gastrectomy drastically reduced the stimulated gastric secretion by a similar proportion for the two secretagogues, thereby implying that antral gastrin plays no greater part in one than in the other. Gastric outlet losses were also reduced after gastrectomy, but as a fraction of gastric contents, both gastric outlet loss and enterogastric reflux more than doubled; the possible relationship of these findings to the aetiology of gastric ulcer is discussed.

The clinical significance of gastric acid secretion in bilharzial hepatic fibrosis

Gastric acid secretion was studied in 19 patients with bilharzial hepatic fibrosis and in 19 healthy controls. The patients had significantly lower volumes and acid output than the control group. After splenectomy and vasoligation, the patients' gastric secretion did not increase significantly. Gastric secretion was similar in 19 patients with bilharzial hepatic fibrosis who had never experienced any episode of bleeding and in 19 who bled.

Assay and identification of histamine in human gastric aspirate by a fluorometric--fluoroenzymatic technique. Its application in patients with chronic duodenal ulcer

Histamine assays can be unreliable in individual subjects or samples even though the particular method is in general working very well. Therefore the specificity and accuracy of histamine determination in the gastric aspirate of individual duodenal ulcer patients was thoroughly examined and shown to be satisfactory. Pitfalls of the fluorometric assay were investigated. A native (non-histamine) fluorescence in gastric aspirate which occurs before the addition of OPT was not removed by the original Shore procedure. In the combined assay (Dowex 50 + butanol extraction) this fluorescence no longer interferes with the assay. For the identification of histamine in a single gastric aspirate of an individual duodenal ulcer patient, the reversed blank (3 M HCl added to the reaction mixture before OPT instead after OPT), excitation and fluorescence spectra, the heating test with spectra recorded and the HMT test were found to be reliable. The formaldehyde test and the heating test without recording the spectra were useless since they gave false negative results. Since the HMT test was regarded as a reference method it was thoroughly investigated both by theoretical considerations (enzyme kinetics) and by a series of measurements in a single patient as well as in a group of nine subjects. Samples from the period of peak acid output in response to pentagastrin showed an average histamine concentration of about 8 ng/ml and a histamine output of 1.5 microgram/30 min.