title: Effects of Bolus and Continuous Nasogastric Feeding on Gastric Emptying, Small Bowel Water Content, Superior Mesenteric Artery Blood Flow, and Plasma Hormone Concentrations in Healthy Adults: A Randomized Crossover Study.
abstract: OBJECTIVE
  We aimed to demonstrate the effect of continuous or bolus nasogastric feeding on gastric emptying, small bowel water content, and splanchnic blood flow measured by magnetic resonance imaging (MRI) in the context of changes in plasma gastrointestinal hormone secretion.
  
  
  BACKGROUND
  Nasogastric/nasoenteral tube feeding is often complicated by diarrhea but the contribution of feeding strategy to the etiology is unclear.
  
  
  METHODS
  Twelve healthy adult male participants who underwent nasogastric intubation before a baseline MRI scan, received 400  mL of Resource Energy (Nestle) as a bolus over 5 minutes or continuously over 4  hours via pump in this randomized crossover study. Changes in gastric volume, small bowel water content, and superior mesenteric artery blood flow and velocity were measured over 4  hours using MRI and blood glucose and plasma concentrations of insulin, peptide YY, and ghrelin were assayed every 30 minutes.
  
  
  RESULTS
  Bolus nasogastric feeding led to significant elevations in gastric volume (P < 0.0001), superior mesenteric artery blood flow (P < 0.0001), and velocity (P = 0.0011) compared with continuous feeding. Both types of feeding reduced small bowel water content, although there was an increase in small bowel water content with bolus feeding after 90 minutes (P < 0.0068). Similarly, both types of feeding led to a fall in plasma ghrelin concentration although this fall was greater with bolus feeding (P < 0.0001). Bolus feeding also led to an increase in concentrations of insulin (P = 0.0024) and peptide YY (P < 0.0001), not seen with continuous feeding.
  
  
  CONCLUSIONS
  Continuous nasogastric feeding does not increase small bowel water content, thus fluid flux within the small bowel is not a major contributor to the etiology of tube feeding-related diarrhea.
authors.affiliation: *Nottingham Digestive Diseases Centre, National Institute for Health Research, Biomedical Research Unit, Nottingham University Hospitals, Queen's Medical Centre, Nottingham, UK †Sir Peter Mansfield Magnetic Resonance Centre, School of Physics and Astronomy, University of Nottingham, Nottingham, UK ‡Metabolic Physiology Group, University of Nottingham, Nottingham, UK §Department of Gastroenterology, Nottingham University Hospitals NHS Trust, Nottingham, UK.
authors.forename: Abeed H
authors.initials: AH
authors.lastname: Chowdhury
authors.forename: Kathryn
authors.initials: K
authors.lastname: Murray
authors.forename: Caroline L
authors.initials: CL
authors.lastname: Hoad
authors.forename: Carolyn
authors.initials: C
authors.lastname: Costigan
authors.forename: Luca
authors.initials: L
authors.lastname: Marciani
authors.forename: Ian A
authors.initials: IA
authors.lastname: Macdonald
authors.forename: Timothy E
authors.initials: TE
authors.lastname: Bowling
authors.forename: Dileep N
authors.initials: DN
authors.lastname: Lobo
mesh_terms: D001783:Blood Flow Velocity / Q000502:physiology*; D001834:Body Water / Q000378:metabolism; D018592:Cross-Over Studies; D003967:Diarrhea / Q000209:etiology; D004739:England; D004750:Enteral Nutrition / Q000379:methods*; D005746:Gastric Emptying / Q000502:physiology*; D005768:Gastrointestinal Hormones / Q000097:blood*; D064368:Healthy Volunteers; D006801:Humans; D007421:Intestine, Small / Q000502:physiology*; D007441:Intubation, Gastrointestinal; D008279:Magnetic Resonance Imaging; D008297:Male; D017538:Mesenteric Artery, Superior / Q000502:physiology*; D055815:Young Adult
chemical_list: D005768:Gastrointestinal Hormones