The impact of continuous positive airway pressure on the lower esophageal sphincter
- 1 May 2007
- journal article
- Published by American Physiological Society in American Journal of Physiology-Gastrointestinal and Liver Physiology
- Vol. 292 (5), G1200-G1205
- https://doi.org/10.1152/ajpgi.00476.2006
Abstract
The lower esophageal sphincter (LES) is the primary barrier to gastroesophageal reflux. Reflux is associated with periods of LES relaxation, as occurs during swallowing. Continuous positive airway pressure (CPAP) has been shown to reduce reflux in individuals with and without sleep apnea, by an unknown mechanism. The aim of this study was to determine the effect of CPAP on swallow-induced LES relaxation. Measurements were made in 10 healthy, awake, supine individuals. Esophageal (Pes), LES (Ples), gastric (Pg), and barrier pressure to reflux (Pb = Ples − Pg) were recorded using a sleeve catheter during five swallows of 5 ml of water. This was repeated at four levels of CPAP (0, 5, 10, and 15 cmH2O). Pressures were measured during quiet breathing and during the LES relaxation associated with a swallow. Duration of LES relaxation was also recorded. During quiet breathing, CPAP significantly increased end-expiratory Pes, Ples, Pg, and Pb ( P < 0.05). The increase in Pb was due to a disproportionate increase in Ples compared with Pg ( P < 0.05). During a swallow, CPAP increased nadir Ples, Pg, and Pb and decreased the duration of LES relaxation (4.1 s with 0-cmH2O CPAP to 1.6 s on 15-cmH2O CPAP, P < 0.001). Pb increased with CPAP by virtue of a disproportionate increase in Ples compared with Pg. This may be due to either reflex activation of LES smooth muscle, or nonspecific transmission of pressure to the LES. The findings suggest CPAP may make the LES less susceptible to reflux by increasing Pb and decreasing the duration of LES relaxation.Keywords
This publication has 21 references indexed in Scilit:
- Nasal Continuous Positive Airway PressureJournal of Clinical Gastroenterology, 1993
- Nasal CPAP Reduces Gastroesophageal Reflux in Obstructive Sleep Apnea SyndromeChest, 1992
- Effect of lung inflation and upright posture on diaphragmatic shortening in dogsRespiration Physiology, 1991
- Modulation of esophageal peristalsis by alterations of body positionDigestive Diseases and Sciences, 1989
- Effect of sleep, spontaneous gastroesophageal reflux, and a meal on upper esophageal sphincter pressure in normal human volunteersGastroenterology, 1987
- Is abdominal compression a useful stimulation test for analysis of lower esophageal sphincter function?Digestive Diseases and Sciences, 1984
- Mechanism of gastroesophageal reflux in recumbent asymptomatic human subjects.JCI Insight, 1980
- Patterns of Gastroesophageal Reflux in Health and DiseaseAnnals of Surgery, 1976
- Effects of increased intra-abdominal pressure on esophageal peristalsis.Journal of Applied Physiology, 1974
- The Mechanics of Esophageal Muscle Contraction. EVIDENCE OF AN INOTROPIC EFFECT OF GASTRINJCI Insight, 1973