title: Influence of Full-body Water Immersion on Esophageal Motor Function and Intragastric Pressure.
abstract: OBJECTIVE
  In Japan, it is customary to take a daily bath during which the body is immersed in water to the neck. During full-body immersion, hydrostatic pressure is thought to compress the chest and abdomen, which might influence esophageal motor function and intra-gastric pressure. However, whether water immersion has a significant influence on esophageal motor function or intragastric pressure has not been shown. The aim of this study was to clarify the influence of full-body water immersion on esophageal motor function and intragastric pressure.
  
  
  METHODS
  Nine healthy male volunteers (mean age 40.1 ± 2.8 years) were enrolled in this study. Esophageal motor function and intragastric pressure were investigated using a high-resolution 36-channel manometry device.
  
  
  RESULTS
  All subjects completed the study protocol. Intragastric pressure increased significantly from 4.2 ± 1.1 to 20.6 ± 1.4 mmHg with full-body water immersion, while the lower esophageal high pressure zone (LEHPZ) value also increased from 20.5 ± 2.2 to 40.4 ± 3.6 mmHg, with the latter being observed regardless of dietary condition. In addition, peak esophageal peristaltic pressure was higher when immersed as compared to standing out of water.
  
  
  CONCLUSIONS
  Esophageal motor function and intragastric pressure were altered by full-body water immersion. Furthermore, the pressure gradient between LEHPZ and intragastric pressures was maintained at a high level, and esophageal peristaltic pressure was elevated with immersion.
authors.affiliation: Department of Gastroenterology and Hepatology, Shimane University School of Medicine, Shimane, Japan.
authors.forename: Masahito
authors.initials: M
authors.lastname: Aimi
authors.forename: Kenji
authors.initials: K
authors.lastname: Furuta
authors.forename: Tsukasa
authors.initials: T
authors.lastname: Saito
authors.forename: Shino
authors.initials: S
authors.lastname: Shimura
authors.forename: Kousuke
authors.initials: K
authors.lastname: Fukazawa
authors.forename: Shunji
authors.initials: S
authors.lastname: Ohara
authors.forename: Goichi
authors.initials: G
authors.lastname: Uno
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Tobita
authors.forename: Kyoichi
authors.initials: K
authors.lastname: Adachi
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Kinoshita