Document Detail

Esophageal motor activity and acid clearance.
MedLine Citation:
PMID:  2228163     Owner:  NLM     Status:  MEDLINE    
Esophageal acid clearance normally occurs as a two-step process. The initial step of emptying most of the fluid volume contained within the esophagus occurs quickly by gravity or by one or two peristaltic sequences. However, volume clearance is distinct from acid clearance, and esophageal pH is restored to normal after volume clearance as the 1 mL or so of residual acid is neutralized by swallowed saliva in a stepwise fashion. A considerable body of evidence has accumulated suggesting that about half of patients with reflux disease have markedly prolonged acid clearance times. Within this group abnormalities or both volume clearance and salivation have been demonstrated. Volume clearance may be impaired as a result of a breakdown of the peristaltic mechanism commonly seen with severe esophagitis or by "re-reflux" of cleared fluid from within a hiatal hernia. Either way, the result is increased residual acidic fluid within the esophagus. The increased residual acid must be titrated with saliva that has so slight a neutralizing capacity that it takes about 7 minutes for the average person to secrete enough saliva to titrate 1 mL of 0.1 N HCl. Salivation itself is reduced in cigarette smokers and in patients using anticholinergic medications, thereby prolonging the process of mucosal neutralization in such persons. Whatever the mechanism of prolonged acid clearance for a particular individual, the overall result is of prolonged esophageal mucosal acid exposure, which makes the development of peptic esophagitis more likely.
P J Kahrilas
Related Documents :
1335173 - Modulation of pulmonary immune defense mechanisms by sulfuric acid: effects on macropha...
17895353 - Mechanisms of acid, weakly acidic and gas reflux after anti-reflux surgery.
3084923 - Purification and immunochemical properties of a protein antigen from serotype g strepto...
Publication Detail:
Type:  Journal Article; Review    
Journal Detail:
Title:  Gastroenterology clinics of North America     Volume:  19     ISSN:  0889-8553     ISO Abbreviation:  Gastroenterol. Clin. North Am.     Publication Date:  1990 Sep 
Date Detail:
Created Date:  1990-12-12     Completed Date:  1990-12-12     Revised Date:  2005-11-16    
Medline Journal Info:
Nlm Unique ID:  8706257     Medline TA:  Gastroenterol Clin North Am     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  537-50     Citation Subset:  IM    
Department of Medicine, Northwestern University, Chicago, Illinois.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Esophagitis, Peptic / physiopathology*
Esophagogastric Junction / physiology*
Esophagus / physiology*
Gastroesophageal Reflux / physiopathology*
Peristalsis / physiology
Salivation / physiology

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Pathophysiology of gastroesophageal reflux. Lower esophageal sphincter dysfunction in gastroesophage...
Next Document:  Esophageal mucosal resistance. A factor in esophagitis.