Oesophageal motor events at the occurrence of acid reflux and during endogenous acid exposure in healthy subjects and in patients with oesophagitis.

Abstract

SUMMARY In order to assess the oesophageal motor events associated with the occurrence of gastro-oesophageal acid reflux and those during endogenous acid exposure, we studied six healthy subjects and nine patients with symptoms and lesions of reflux oesophagitis. In the case of each subject simultaneous pressure and pH measurements of the distal oesophagus were taken both in fasting conditions and after a standardised balanced meal. Reflux episodes occurred in the absence of a lower oesophageal sphincter relaxation (34.3%, 17-7%) or in the presence of a relaxation associated (34-2%, 30.8%) or unassociated (31.5%, 51.5%) with a peristaltic sequence, in the controls and patients respectively. No significant differences were found between the two groups. During endogenous acid perfusion the distal oesophagus showed mainly a peristaltic motor activity, but the mean hourly number of peristaltic sequences was significantly lower in the patients than in the controls (33-5±27-2 vs 81-5±3-2, p<0.01). Our results show that the mechanisms of reflux are similar in controls and in patients, while the peristaltic frequency is reduced in the latter. This motor failure may be responsible for the increased reflux duration observed in patients with oesophagitis.Gastro-oesophageal acid reflux can be assessed and quantified by means of reliable techniques.1 2 Nevertheless, there is no agreement regarding the mechanisms of reflux; this is particularly true with regard to the role of the lower oesophageal sphincter. Some authors35 consider a low basal tone of the lower oesophageal sphincter a major cause of reflux, whereas others6 7 suggest that reflux may be related to sphincteric relaxations, particularly when they occur in the absence of a peristaltic sequence.Moreover, manometric studies have shown a failure of the peristaltic function of the oesophageal body in patients with oesophagitis both in basal conditions8S-" and during exogenous acid exposure of the oesophageal mucosa. 1213 Little information is available regarding oesophageal motilitT during reflux induced endogenous acid exposure.The aim of our study was to evaluate, in normal subjects and in patients with oesophagitis: (a) the oesophageal motor events at the occurrence of Address for correspondence: Dr F Baldi, III Clinica Medica, Policlinico S. Orsola, via Massarenti n. 9, 40138 Bologna, Italy. Received for publication 15 June 1984 gastro-oesophageal acid reflux, and (b) the motor activity of the distal oesophagus during acid reflux. Methods SUBJECTSWe performed oesophageal motility and pH studies on six healthy volunteers (four men, age range 23-41 years) and nine patients (six men, age range 24-59 years) with heartburn and/or regurgitation of at least six months duration and endoscopically proved erosive oesophagitis, in the absence of peptic stricture.

End Expiration Is More Accurate than Mid Respiration in Measuring Lower Esophageal Sphincter Pressure

“…Gastroesophageal reflux can occur despite normal LES pressure [16]because of transient [17, 18, 19, 20, 21, 22]and swallow-induced LES relaxation [23, 24]. Nevertheless, a LES pressure of <6 mm Hg is frequently associated with the severe types of esophagitis [25].…”

The Effect of Ranitidine on Oesophageal Motility

“…These studies were carried out in smaller series than ours, comprising 6-10 subjects (3)(4)(5), and 2 of these studies were conducted after a single dose of ranitidine ( 3 , 5 ) . We have used 3 doses, mimicking a clinical steady-state situation more closely, and have carried out 2 placebo studies in each subject, thereby obtaining a total of 42 control observations.…”

“…They reduce gastric acid secretion and the number of acid oesophageal regurgitations (1)(2)(3). Previous studies of the effect o f cimetidine and ranitidine on lower oesophageal sphincter (LOS) pressure have been contradictory (3)(4)(5)(6)(7)(8)(9)(10). Single peroral doses of ranitidine did not seem to affect LOS pressure in small series of volunteers (3)(4)(5).…”

“…Previous studies of the effect o f cimetidine and ranitidine on lower oesophageal sphincter (LOS) pressure have been contradictory (3)(4)(5)(6)(7)(8)(9)(10). Single peroral doses of ranitidine did not seem to affect LOS pressure in small series of volunteers (3)(4)(5). whereas intravenous administration has been reported to increase LOS pressure (6.7).…”

Clinical Value of Esophageal Motility Testing

“…Infrequent peristalsis [42,57], impaired peristalsis [58], and/or diminished salivation [59,60] all can prolong esophageal acid exposure time. While these disorders of peristalsis are assessed during esophageal motility testing, salivation is not.…”