The effect of position on esophageal structure and function determined with solid-state high-resolution manometry.
OBJECTIVE
To investigate the influence of posture on the anatomy and function of esophageal sphincters using solid-state high-resolution manometry.


METHODS
Fifty individuals underwent esophageal manometry with a 36-channel solid-state catheter in the supine and upright positions. The length and pressure of the esophageal sphincters, as well as the esophageal and intra-abdominal lengths of lower esophageal sphincter (LES), were recorded. The residual pressure of the upper esophageal sphincter (UES) and the 4-s integrated relaxation pressure were also measured when the participants swallowed 10 consecutive servings of water (5 mL each). The Bland-Altman plot was used to assess agreement between these parameters in the supine and upright positions.


RESULTS
The LES resting pressure was significantly decreased in the upright position compared with the supine position (13.85 ± 5.90 mmHg vs 18.09 ± 7.80 mmHg, P = 0.000). Weaker integrated relaxation pressures were observed when the participants were in the upright position (5.66 ± 3.33 mmHg vs 7.80 ± 3.25 mmHg, P = 0.000). Compared with the supine position, the upright esophageal length was longer (P = 0.004) and the upper border of the LES was lower (P = 0.050) when the individuals were in the upright position. The agreement between the two positions was acceptable for the esophageal length, LES upper border location and LES pressure measurements.


CONCLUSIONS
Body position exerts a greater influence on the LES than on the UES. Thus, it is necessary to establish normal values for the LES basal pressure and residual pressure in different positions.
Division of Gastroenterology, North China University of Science and Technology Affiliated Hospital, Tangshan, Hebei Province, China.|Division of Gastroenterology, Union Hospital of Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, China.
Xiu Jing
XJ
Zhang
Division of Gastroenterology, Union Hospital of Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, China.
Xue Lian
XL
Xiang
Division of Gastroenterology, Union Hospital of Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, China.
Lei
L
Tu
Division of Gastroenterology, Union Hospital of Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, China.
Xiao Ping
XP
Xie
Division of Gastroenterology, Union Hospital of Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, China.
Xiao Hua
XH
Hou
D000328:Adult; D015154:Esophageal Motility Disorders; D049630:Esophageal Sphincter, Lower / Q000503:physiopathology; D004947:Esophagus / Q000033:anatomy & histology* / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008365:Manometry / Q000379:methods*; D008875:Middle Aged; D056888:Patient Positioning / Q000379:methods*; D011187:Posture / Q000502:physiology*
esophageal motility; esophageal sphincter; manometry; posture