The gastropulmonary route of infection—Fact or fiction?

https://doi.org/10.1016/0002-9343(91)90466-BGet rights and content

Abstract

Published studies relating to whether medicinal stress-bleeding prophylaxis leading to an increase of gastric pH favors the development of bronchopulmonary infections are reviewed. Results from studies in healthy humans, patients with ulcer disease, and patients in the intensive care unit (ICU) clearly show that the risk of gastric bacterial colonization significantly increases relative to increasing gastric pH. Moreover, a drug-induced increase of gastric pH leads directly to gastric bacterial colonization also in patients in the ICU, above all with bacteria typical of the gastrointestinal tract. Comparing the different bacterial spectra of the oropharynx, stomach, and upper small intestine, it becomes clear that the stomach is a reservoir of bacteria independent of the oropharynx and also subject to retrograde colonization due to the duodenogastric reflux. Both by means of microbiological and in particular direct detection procedures, it can be demonstrated that in at least 30–40% of intubated patients a gastropulmonary route of colonization occurs. In patient groups without a medication-induced increase of gastric pH the number of bacteria detected in the tracheal secretion is about 33% less than in the case of conventional stress-bleeding prophylaxis. These findings make it understandable that a highly significant increase in the pneumonia rate is seen in patients receiving pH-increasing stress-bleeding prophylaxis versus control groups without therapy essentially influencing gastric pH. A risk score was developed that allows an easy description of those patients who are at an increased risk of pulmonary infections due to the gastropulmonary route of colonization.

References (65)

  • A Forster et al.

    Influence de la cimetidine sur la croissance bacterienne dans le liquide gastrique

    Nouv Presse Med

    (1982)
  • JJ Lehot et al.

    Should we inhibit gastric acid secretion before cardiac surgery?

    Anesth Analg

    (1990)
  • HJ Hagel von et al.

    Keimbesiedlung des Magens durch Säureneutralisation und Hemmung der Magenentleerung

    Z Gastroenterol

    (1985)
  • RW Stockbrügger et al.

    Intragastric nitrates, nitrosamines and bacterial overgrowth during cimetidine treatment

    Gut

    (1982)
  • PJ Reed et al.

    Gastric juice N-nitrosamines in health and gastrointestinal disease

    Lancet

    (1980)
  • DL Morris et al.

    The influence of sucralfate or cimetidine on gastric juice pH, bacterial flora and mutagenicity

    Dig Surg

    (1984)
  • RW Stockbrügger et al.

    The intragastric milieu during gastric ulcer treatment with pirenzepine 50 mg b.i.d, or cimetidine 400 mg b.i.d.

    Z Gastroenterol

    (1988)
  • KM Hillman et al.

    Colonization of the gastric content in critically ill patients

    Crit Care Med

    (1982)
  • F Daschner et al.

    Der Einfluß von Streßulcusprophylaxe auf die Häufigkeit einer Beatmungspneumonie

    Anaesthesist

    (1987)
  • LG Donowitz et al.

    Alteration of normal gastric flora in critical care patients receiving antacid and cimetidine therapy

    Infect Control

    (1986)
  • RJ Kahn et al.

    Influence of antacid treatment on the tracheal flora in mechanically ventilated patients

    Crit Care Med

    (1982)
  • A Benke et al.

    Ranitidin und Cimetidin: Ihr Einfluß auf pH und Keimbesiedlung des Magens sowie auf die Mikrobiologie der oberen Luftwege

    Anaesthesist

    (1985)
  • W Mauritz et al.

    Keimflora in Magensaft und Bronchialsekret bei langzeitbeatmeten Intensivpatienten

    Anaesthesist

    (1985)
  • T Hase et al.

    Significance of gastric secretory changes in pathogenesis of stress ulcers

    Dig Dis

    (1975)
  • G Marggraf et al.

    Perioperative Streßblutungsprophylaxe bei herzchirurgischen Eingriffen

    Anaesthesist

    (1989)
  • VA Stannard et al.

    Gastric exocrine “failure” in critically ill patients: incidence and associated features

    Br Med J

    (1988)
  • GM Larson et al.

    Intracranial pressure, gastrin and acid secretion in severe head injury

    Surg Forum

    (1982)
  • MR Driks et al.

    Nosocomial pneumonia in intubated patients randomized to sucralfate versus antacids and/or histamine type 2 blockers: the role of gastric colonization

    N Engl J Med

    (1987)
  • S Sjöstedt et al.

    Microbial colonization of the oropharynx, esophagus and stomach in patients with gastric diseases

    Eur J Clin Microbiol

    (1985)
  • S Sjöstedt et al.

    Microbial colonization of tumors in relation to the upper gastrointestinal tract in patients with gastric carcinoma

    Ann Surg

    (1988)
  • P Bach-Nielsen et al.

    Peroperative bacteriologic examination of the stomach and duodenum

    Acta Chir Scand

    (1965)
  • JDA Gray et al.

    Influence of gastric pH on gastric and jejunal flora

    Gut

    (1977)

    • Cited by (64)

    • Prevention of hospital-acquired pneumonia:: European perspective

      2003, Infectious Disease Clinics of North America

    • Surveillance of enteral nutrition, complications and prevention

      2003, Reanimation

    • Statement of the Fourth International Consensus Conference in critical care on ICU-acquired pneumonia

      2002, Reanimation

    • Nutrometabolic support in the critical surgical patient

      2001, Cirugia Espanola

    • Acidification of formula reduces bacterial translocation and gut colonization in a neonatal rabbit model

      2001, Journal of Pediatric Surgery
      Citation Excerpt :

      This confirms that a pH below 4, whether through native gastric acid production or formula acidification, effects bacterial killing and exerts protection from bacterial translocation and gut colonization. The concept of gastric colonization as a source of infection received little attention until recognition of the increased infectious morbidity associated with stress gastritis prophylaxis and induced gastric neutrality through enteral feedings.13,18,27-33 Since that time, renewed interest in restoring the natural defense of gastric acidity has ensued.

    • Risk factors for nosocomial pneumonia: Focus on prophylaxis

      2001, Medical Clinics of North America
      Citation Excerpt :

      In a more recent study, 75% of the pathogens causing VAP in ICU patients had been identified previously as colonizing the oropharynx.9 In mechanically ventilated patients, the stomach and gastrointestinal tract may be a source of oropharyngeal and tracheal pathogens, particularly in late-onset VAP.38,39,78,102 Although the stomach is usually sterile at a pH less than 3, dramatic increases in gastric colonization (≥100,000 to 1 million bacteria/mL of gastric juice at a pH >3.5) have been reported in patients with advanced age, achlorhydria, various gastrointestinal diseases, malnutrition, or use of antacids and histamine type 2 (H2) blockers or enteral feeding.2,38,39

    View all citing articles on Scopus
    View full text
    Copyright © 1991 Published by Excerpta Medica Inc.