title: Managing gastric residual volumes in the critically ill patient: an update.
abstract: OBJECTIVE
  Gastric residual volumes (GRVs) remain a major deterrent to adequately feeding patients with gastric-delivered enteral nutrition. The purpose of this review was to define the most up-to-date consensus of the utility of the use of GRVs for monitoring tube-feeding intolerance in gastric-fed patients.
  
  
  RESULTS
  The paper summarizes the pathophysiology of gastroparesis, the techniques for measuring GRVs, the significance of a large GRV, other factors to consider when measuring GRVs, the correlation between GRVs and aspiration pneumonia, national guideline statements on GRVs, the use of prokinetic agents in the treatment of high GRVs and the clinical impact of tolerating larger GRVs. The utility of GRVs for prevention of aspiration events with tube feeding has been brought into question.
  
  
  CONCLUSIONS
  Large GRVs usually result from some impediment in gastrointestinal motility (e.g. gastroparesis). There are numerous methods for measuring GRVs, most of which have not been standardized. It appears that there is little correlation between large GRVs and the development of aspiration pneumonia when tube feeding patients. Prokinetic agents have an inconsistent effect on the GRV size. US guidelines state that GRVs of less than 500 ml should not result in termination of enteral feeding. Allowing larger GRVs will allow patients to receive more calories when gastric fed without a deleterious clinical impact. The use of GRVs as a marker of feeding tolerance is of questionable utility.
authors.affiliation: Digestive Disease Center, Medical University of South Carolina, Charleston, South Carolina 29425, USA. deleggem@musc.edu
authors.forename: Mark H
authors.initials: MH
authors.lastname: DeLegge
mesh_terms: D016638:Critical Illness / Q000628:therapy*; D004750:Enteral Nutrition; D005526:Food, Formulated; D005746:Gastric Emptying / Q000502:physiology*; D005766:Gastrointestinal Contents / Q000737:chemistry; D005769:Gastrointestinal Motility / Q000502:physiology*; D006801:Humans; D007441:Intubation, Gastrointestinal / Q000009:adverse effects*; D011015:Pneumonia, Aspiration / Q000517:prevention & control