title: The effect of water bolus temperature on esophageal motor function as measured by high-resolution manometry.
abstract: BACKGROUND
  Ingestion of cold fluids may induce pain in patients with esophageal motility disorders. Hot fluids, on the other hand, may help to relieve pain. We studied changes in esophageal motility as a variable of water bolus temperature using high-resolution manometry (HRM) in healthy human.
  
  
  METHODS
  Thirty-two healthy subjects were recruited at Kosin University Hospital. HRM was performed in a sitting position, with room temperature (RT, 25 °C), hot (45 °C), and cold (2 °C) water swallowed in that order. This exam included single swallowing (10 swallows of 5 mL water, 30 s intervals) and multiple water swallows (MWS; 100 mL water within 30 s).
  
  
  RESULTS
  In the single swallowing, hot water caused a decrease in lower esophageal sphincter (LES) residual pressure (5.87 ± 4.20 mmHg vs 7.45 ± 4.17 mmHg (RT), p = 0.001) and duration of esophageal body (EB) contraction (3.01 ± 0.80 s vs 3.15 ± 1.16 s (RT), p = 0.009). Cold water caused an increase in the duration of EB contraction (3.52 ± 0.87 s vs 3.15 ± 1.16 s (RT), p = 0.001) and a decrease in contractile front velocity (CFV) (4.43 ± 1.50 cm/s vs 4.90 ± 2.53 cm/s (RT), p = 0.007). Similarly, in the MWS, hot water caused a decrease in the duration of EB contraction (12.95 ± 5.02 s vs 16.33 ± 5.94 s (RT), p = 0.024) and an increase in the amplitude of EB contraction (114.27 ± 83.36 mmHg vs 82.70 ± 46.77 mmHg (RT), p = 0.007). Cold water caused an increase in the duration of EB contraction (27.38 ± 2.89 s vs 16.33 ± 5.94 s (RT), p = 0.03) and a decrease in the amplitude of EB contraction (51.68 ± 33.94 mmHg vs 82.70 ± 46.77 mmHg (RT), p = 0.001).
  
  
  CONCLUSIONS
  This study showed changes in esophageal motility to be dependent on water temperature. Especially, MWS showed clear changes in esophageal motility at different temperatures of water.
authors.affiliation: Department of Internal Medicine, Kosin University College of Medicine, Busan, South Korea.
authors.forename: Y J
authors.initials: YJ
authors.lastname: Choi
authors.forename: M I
authors.initials: MI
authors.lastname: Park
authors.forename: S J
authors.initials: SJ
authors.lastname: Park
authors.forename: W
authors.initials: W
authors.lastname: Moon
authors.forename: S E
authors.initials: SE
authors.lastname: Kim
authors.forename: H J
authors.initials: HJ
authors.lastname: Kwon
authors.forename: J H
authors.initials: JH
authors.lastname: Kim
authors.forename: W S
authors.initials: WS
authors.lastname: Jeon
mesh_terms: D000328:Adult; D049630:Esophageal Sphincter, Lower / Q000502:physiology*; D004947:Esophagus / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008365:Manometry / Q000379:methods; D008875:Middle Aged; D009119:Muscle Contraction / Q000502:physiology; D009130:Muscle, Smooth / Q000502:physiology; D010528:Peristalsis / Q000502:physiology*; D013696:Temperature; D014867:Water; D055815:Young Adult
chemical_list: D014867:Water
keywords: bolus temperature; esophageal body contraction; high-resolution manometry; lower esophageal sphincter; multiple water swallows