title: The lower oesophageal sphincter in the first trimester of pregnancy: comparison of supine with lithotomy positions.
abstract: Measurement were made of gastric pressure (GP), lower oesophageal sphincter pressure (LOSP) and barrier pressure (BrP) in the supine and lithotomy positions in 17 healthy women undergoing termination of pregnancy in the first trimester. Values in the supine position were similar to those seen in non-pregnant subjects, but there was a significant reduction in LOSP and BrP in the lithotomy position unrelated to any change in intragastric pressure. It is concluded that the lithotomy position is associated with increased risk of regurgitation in early pregnancy.
authors.affiliation: University Department of Anaesthesia, Leicester Royal Infirmary.
authors.forename: M J
authors.initials: MJ
authors.lastname: Jones
authors.forename: R W
authors.initials: RW
authors.lastname: Mitchell
authors.forename: N
authors.initials: N
authors.lastname: Hindocha
authors.forename: R H
authors.initials: RH
authors.lastname: James
mesh_terms: D000293:Adolescent; D000328:Adult; D004943:Esophagogastric Junction / Q000502:physiology*; D005260:Female; D006801:Humans; D011187:Posture; D011247:Pregnancy / Q000502:physiology*; D011261:Pregnancy Trimester, First; D011312:Pressure; D013270:Stomach / Q000502:physiology; D013484:Supination