title: Effect of the preliminary hydration on gastric emptying time for water in healthy volunteers.
abstract: BACKGROUND
  International guidelines allow healthy patients to drink clear liquid up to 2 h before general anesthesia. Recently, MRI measurements have been used for tracking gastric volume in humans. Hence, we used MRI to examine the gastric emptying rate of water in healthy volunteers with or without prior water loading.
  
  
  METHODS
  Fifteen healthy volunteers were enrolled. The participants had MRI examinations on separate days under two different protocols: The preliminary hydration protocol (group H) and the water restriction protocol (group R). After the intake of water, MR imaging was performed every 10 min for 60 min. The gastric content was outlined as area of interest (AOI), and the AOI area of each slice was summated to calculate the volume of gastric contents.
  
  
  RESULTS
  The 50% reduction time of gastric volume in group R and group H was 18+/-9 and 16+/-8 min (mean+/-SD), respectively. There were no significant changes between the two groups.
  
  
  CONCLUSIONS
  The gastric emptying time for water evaluated with MRI was not affected by preliminary hydration, which shows the safety of repeated oral hydrations in the pre-operative period.
authors.affiliation: Department of Anesthesiology, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Umenai
authors.forename: N
authors.initials: N
authors.lastname: Arai
authors.forename: E
authors.initials: E
authors.lastname: Chihara
mesh_terms: D000328:Adult; D004326:Drinking; D005260:Female; D005746:Gastric Emptying / Q000187:drug effects*; D005766:Gastrointestinal Contents / Q000187:drug effects; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009929:Organ Size / Q000187:drug effects; D011300:Preoperative Care / Q000592:standards; D013270:Stomach / Q000187:drug effects; D014867:Water / Q000008:administration & dosage / Q000494:pharmacology*; D014868:Water Deprivation; D055815:Young Adult
chemical_list: D014867:Water