Skip to main content
NCBI home page
Gut logoLink to Gut
. 1994 Jun;35(6):737–741. doi: 10.1136/gut.35.6.737

Effect of ranitidine on basal and bicarbonate enhanced intragastric PCO2: a tonometric study.

J J Kolkman 1, A B Groeneveld 1, S G Meuwissen 1
PMCID: PMC1374868  PMID: 8020795

Abstract

A high intragastric PCO2 (iPCO2), determined tonometrically, is the main factor participating in a low gastric intramucosal pH (pHi) and may point to gastric mucosal ischaemia. iPCO2 might also increase, however, after buffering of gastric acid by bicarbonate; the magnitude of this effect and the efficacy of H2 blockers to prevent it are unclear. Ten healthy volunteers (20-24 years) were studied at baseline and after oral ingestion of 500 mg sodium bicarbonate. The same test was carried out one hour after intravenous injection of 100 mg ranitidine. A glass pH electrode for continuous gastric juice pH measurements and a Tonomitor catheter were placed 10 cm distally from the gastro-oesophageal junction. iPCO2 was measured in saline boluses, infused at 30 minute intervals in the balloon at the tip of the Tonomitor. Before ranitidine was given, basal iPCO2 (mean (SD)) was 8.40 (2.53) kPa, and increased to 19.20 (5.87) kPa after sodium bicarbonate (p < 0.001). After ranitidine, the gastric juice pH increased from 1.8 (0.9) to 5.6 (1.3) (p < 0.05), while basal iPCO2 was 5.60 (0.67) kPa (p < 0.01) and did not change after sodium bicarbonate (6.27 (2.67) kPa)). iPCO2 values after acid secretion suppression were similar to those in capillary blood (5.60 (0.40 kPa)). The difference between intragastric and blood PCO2 during normal acid secretion probably results from buffering of gastric acid by gastric bicarbonate, rather than by duodenogastric reflux or saliva entering the stomach. During acid secretion suppression, intragastric equals blood PCO2, even after oral ingestion of sodium bicarbonate. Hence, acid secretion inhibition is mandatory for proper assessment of iPCO2 and pHi as specific measures of the adequacy of gastric mucosal blood flow.

Full text

PDF
737

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Antonsson J. B., Boyle C. C., 3rd, Kruithoff K. L., Wang H. L., Sacristan E., Rothschild H. R., Fink M. P. Validation of tonometric measurement of gut intramural pH during endotoxemia and mesenteric occlusion in pigs. Am J Physiol. 1990 Oct;259(4 Pt 1):G519–G523. doi: 10.1152/ajpgi.1990.259.4.G519. [DOI] [PubMed] [Google Scholar]
  2. Dawson A. M., Trenchard D., Guz A. Small bowel tonometry: assessment of small gut mucosal oxygen tension in dog and man. Nature. 1965 May 29;206(987):943–944. doi: 10.1038/206943b0. [DOI] [PubMed] [Google Scholar]
  3. Doglio G. R., Pusajo J. F., Egurrola M. A., Bonfigli G. C., Parra C., Vetere L., Hernandez M. S., Fernandez S., Palizas F., Gutierrez G. Gastric mucosal pH as a prognostic index of mortality in critically ill patients. Crit Care Med. 1991 Aug;19(8):1037–1040. doi: 10.1097/00003246-199108000-00011. [DOI] [PubMed] [Google Scholar]
  4. Driks M. R., Craven D. E., Celli B. R., Manning M., Burke R. A., Garvin G. M., Kunches L. M., Farber H. W., Wedel S. A., McCabe W. R. Nosocomial pneumonia in intubated patients given sucralfate as compared with antacids or histamine type 2 blockers. The role of gastric colonization. N Engl J Med. 1987 Nov 26;317(22):1376–1382. doi: 10.1056/NEJM198711263172204. [DOI] [PubMed] [Google Scholar]
  5. Fiddian-Green R. G., Amelin P. M., Herrmann J. B., Arous E., Cutler B. S., Schiedler M., Wheeler H. B., Baker S. Prediction of the development of sigmoid ischemia on the day of aortic operations. Indirect measurements of intramural pH in the colon. Arch Surg. 1986 Jun;121(6):654–660. doi: 10.1001/archsurg.1986.01400060048005. [DOI] [PubMed] [Google Scholar]
  6. Fiddian-Green R. G., Baker S. Predictive value of the stomach wall pH for complications after cardiac operations: comparison with other monitoring. Crit Care Med. 1987 Feb;15(2):153–156. doi: 10.1097/00003246-198702000-00015. [DOI] [PubMed] [Google Scholar]
  7. Fiddian-Green R. G., McGough E., Pittenger G., Rothman E. Predictive value of intramural pH and other risk factors for massive bleeding from stress ulceration. Gastroenterology. 1983 Sep;85(3):613–620. [PubMed] [Google Scholar]
  8. Fiddian-Green R. G., Pittenger G., Whitehouse W. M., Jr Back-diffusion of CO2 and its influence on the intramural pH in gastric mucosa. J Surg Res. 1982 Jul;33(1):39–48. doi: 10.1016/0022-4804(82)90007-5. [DOI] [PubMed] [Google Scholar]
  9. Fiddian-Green R. G. Splanchnic ischaemia and multiple organ failure in the critically ill. Ann R Coll Surg Engl. 1988 May;70(3):128–134. [PMC free article] [PubMed] [Google Scholar]
  10. Fiddian-Green R. G., Stanley J. C., Nostrant T., Phillips D. Chronic gastric ischemia. A cause of abdominal pain or bleeding identified from the presence of gastric mucosal acidosis. J Cardiovasc Surg (Torino) 1989 Sep-Oct;30(5):852–859. [PubMed] [Google Scholar]
  11. Forssell H., Olbe L. Continuous computerized determination of gastric bicarbonate secretion in man. Scand J Gastroenterol. 1985 Aug;20(6):767–774. doi: 10.3109/00365528509089211. [DOI] [PubMed] [Google Scholar]
  12. Fuchs K. H., DeMeester T. R., Hinder R. A., Stein H. J., Barlow A. P., Gupta N. C. Computerized identification of pathologic duodenogastric reflux using 24-hour gastric pH monitoring. Ann Surg. 1991 Jan;213(1):13–20. doi: 10.1097/00000658-199101000-00003. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Gores G. J., Nieminen A. L., Wray B. E., Herman B., Lemasters J. J. Intracellular pH during "chemical hypoxia" in cultured rat hepatocytes. Protection by intracellular acidosis against the onset of cell death. J Clin Invest. 1989 Feb;83(2):386–396. doi: 10.1172/JCI113896. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Groeneveld A. B., Vermeij C. G., Thijs L. G. Arterial and mixed venous blood acid-base balance during hypoperfusion with incremental positive end-expiratory pressure in the pig. Anesth Analg. 1991 Nov;73(5):576–582. [PubMed] [Google Scholar]
  15. Grum C. M., Fiddian-Green R. G., Pittenger G. L., Grant B. J., Rothman E. D., Dantzker D. R. Adequacy of tissue oxygenation in intact dog intestine. J Appl Physiol Respir Environ Exerc Physiol. 1984 Apr;56(4):1065–1069. doi: 10.1152/jappl.1984.56.4.1065. [DOI] [PubMed] [Google Scholar]
  16. Gutierrez G., Palizas F., Doglio G., Wainsztein N., Gallesio A., Pacin J., Dubin A., Schiavi E., Jorge M., Pusajo J. Gastric intramucosal pH as a therapeutic index of tissue oxygenation in critically ill patients. Lancet. 1992 Jan 25;339(8787):195–199. doi: 10.1016/0140-6736(92)90002-k. [DOI] [PubMed] [Google Scholar]
  17. Gys T., Hubens A., Neels H., Lauwers L. F., Peeters R. Prognostic value of gastric intramural pH in surgical intensive care patients. Crit Care Med. 1988 Dec;16(12):1222–1224. doi: 10.1097/00003246-198812000-00009. [DOI] [PubMed] [Google Scholar]
  18. Hamilton J. D., Dawson A. M., Webb P. W. Observations upon small gut "mucosal" pO2 and pCO2 in anesthetized dogs. Gastroenterology. 1968 Jul;55(1):52–60. [PubMed] [Google Scholar]
  19. Heard S. O., Helsmoortel C. M., Kent J. C., Shahnarian A., Fink M. P. Gastric tonometry in healthy volunteers: effect of ranitidine on calculated intramural pH. Crit Care Med. 1991 Feb;19(2):271–274. doi: 10.1097/00003246-199102000-00025. [DOI] [PubMed] [Google Scholar]
  20. Ichihara K., Haga N., Abiko Y. Is ischemia-induced pH decrease of dog myocardium respiratory or metabolic acidosis? Am J Physiol. 1984 May;246(5 Pt 2):H652–H657. doi: 10.1152/ajpheart.1984.246.5.H652. [DOI] [PubMed] [Google Scholar]
  21. Isenberg J. I., Hogan D. L., Koss M. A., Selling J. A. Human duodenal mucosal bicarbonate secretion. Evidence for basal secretion and stimulation by hydrochloric acid and a synthetic prostaglandin E1 analogue. Gastroenterology. 1986 Aug;91(2):370–378. [PubMed] [Google Scholar]
  22. Kauffman G. L., Jr, Steinbach J. H. Gastric bicarbonate secretion: effect of pH and topical 16-16 dimethyl prostaglandin E2. Surgery. 1981 Mar;89(3):324–328. [PubMed] [Google Scholar]
  23. Montgomery A., Hartmann M., Jönsson K., Haglund U. Intramucosal pH measurement with tonometers for detecting gastrointestinal ischemia in porcine hemorrhagic shock. Circ Shock. 1989 Dec;29(4):319–327. [PubMed] [Google Scholar]
  24. Odes H. S., Hogan D. L., Steinbach J. H., Ballesteros M. A., Koss M. A., Isenberg J. I. Measurement of gastric bicarbonate secretion in the human stomach: different methods produce discordant results. Scand J Gastroenterol. 1992 Oct;27(10):829–836. doi: 10.3109/00365529209000149. [DOI] [PubMed] [Google Scholar]
  25. Rees W. D., Botham D., Turnberg L. A. A demonstration of bicarbonate production by the normal human stomach in vivo. Dig Dis Sci. 1982 Nov;27(11):961–966. doi: 10.1007/BF01391739. [DOI] [PubMed] [Google Scholar]
  26. Rune S. J. Acid-base parameters of duodenal contents in man. Gastroenterology. 1972 Apr;62(4):533–539. [PubMed] [Google Scholar]
  27. Sanders S. W., Buchi K. N., Moore J. G., Bishop A. L. Pharmacodynamics of intravenous ranitidine after bolus and continuous infusion in patients with healed duodenal ulcers. Clin Pharmacol Ther. 1989 Nov;46(5):545–551. doi: 10.1038/clpt.1989.184. [DOI] [PubMed] [Google Scholar]
  28. Schonholz S., Pleatman M., Kasserman D., Ponsky J. Endoscopic tonometric assessment of intestinal perfusion in a canine model. Gastrointest Endosc. 1989 Sep-Oct;35(5):425–427. doi: 10.1016/s0016-5107(89)72848-0. [DOI] [PubMed] [Google Scholar]
  29. Stevens M. H., Thirlby R. C., Feldman M. Mechanism for high PCO2 in gastric juice: roles of bicarbonate secretion and CO2 diffusion. Am J Physiol. 1987 Oct;253(4 Pt 1):G527–G530. doi: 10.1152/ajpgi.1987.253.4.G527. [DOI] [PubMed] [Google Scholar]
  30. Stokkel L. A., Klinkenberg-Knol E. C., Breedijk M. Microcomputer system for long-term ambulatory pH recording. Med Biol Eng Comput. 1987 Jan;25(1):107–109. doi: 10.1007/BF02442832. [DOI] [PubMed] [Google Scholar]
  31. Tryba M. Sucralfate versus antacids or H2-antagonists for stress ulcer prophylaxis: a meta-analysis on efficacy and pneumonia rate. Crit Care Med. 1991 Jul;19(7):942–949. doi: 10.1097/00003246-199107000-00020. [DOI] [PubMed] [Google Scholar]
  32. Winship D. H., Robinson J. E. Acid loss in the human duodenum. Volume change, osmolal loss, and CO2 production in response to acid loads. Gastroenterology. 1974 Feb;66(2):181–188. [PubMed] [Google Scholar]
  33. von Planta M., Weil M. H., Gazmuri R. J., Bisera J., Rackow E. C. Myocardial acidosis associated with CO2 production during cardiac arrest and resuscitation. Circulation. 1989 Sep;80(3):684–692. doi: 10.1161/01.cir.80.3.684. [DOI] [PubMed] [Google Scholar]

Articles from Gut are provided here courtesy of BMJ Publishing Group

RESOURCES