title: Residual gastric volume evaluation with ultrasonography after ingestion of carbohydrate- or carbohydrate plus glutamine-enriched beverages: a randomized, crossover clinical trial with healthy volunteers.
abstract: BACKGROUND
  - Abbreviation of preoperative fasting to 2 hours with maltodextrin (CHO)-enriched beverage is a safe procedure and may enhance postoperative recovery. Addition of glutamine (GLN) to CHO beverages may include potential benefits to the metabolism. However, by adding a nitrogenous source to CHO beverages, gastric emptying may be delayed and increase the risk of bronchoaspiration during anesthesia.
  
  
  OBJECTIVE
  - In this study of safety, we aimed at investigating the residual gastric volume (RGV) 2 hours after the intake of either CHO beverage alone or CHO beverage combined with GLN.
  
  
  METHODS
  - We performed a randomized, crossover clinical trial. We assessed RGV by means of abdominal ultrasonography (US) in 20 healthy volunteers (10 males and 10 females) after an overnight fast of 8 hours. Then, they were randomized to receive 600 mL (400 mL immediately after US followed by another 200 mL 2 hours afterwards) of either CHO (12.5% maltodextrin) or CHO-GLN (12.5% maltodextrin plus 15 g GLN). Two sequential US evaluations were done at 120 and 180 minutes after ingestion of the second dose. The interval of time between ingestion of the two types of beverages was 2 weeks.
  
  
  RESULTS
  - The mean (SD) RGV observed after 8 hours fasting (13.56±13.25 mL) did not statistically differ (P>0.05) from the RGV observed after ingesting CHO beverage at both 120 (16.32±11.78 mL) and 180 minutes (14.60±10.39 mL). The RGV obtained at 120 (15.63±18.83 mL) and 180 (13.65±10.27 mL) minutes after CHO-GLN beverage also was not significantly different from the fasting condition.
  
  
  CONCLUSIONS
  - The RGV at 120 and 180 minutes after ingestion of CHO beverage combined with GLN is similar to that observed after an overnight fast.
authors.affiliation: Faculdade de Medicina, Universidade Federal de Mato Grosso, MT, Brasil.
authors.forename: Paulo Cesar
authors.initials: PC
authors.lastname: Gomes
authors.affiliation: Faculdade de Medicina, Universidade Federal de Mato Grosso, MT, Brasil.
authors.forename: Cervantes
authors.initials: C
authors.lastname: Caporossi
authors.affiliation: Faculdade de Medicina, Universidade Federal de Mato Grosso, MT, Brasil.
authors.forename: Jose Eduardo
authors.initials: JE
authors.lastname: Aguilar-Nascimento
authors.affiliation: Faculdade de Medicina, Universidade Federal de Mato Grosso, MT, Brasil.
authors.forename: Ageo Mario Candido da
authors.initials: AM
authors.lastname: Silva
authors.affiliation: Faculdade de Medicina, Universidade Federal de Mato Grosso, MT, Brasil.
authors.forename: Viviane Maeve Tavares de
authors.initials: VM
authors.lastname: Araujo
mesh_terms: D000293:Adolescent; D000328:Adult; D001628:Beverages; D018592:Cross-Over Studies; D004311:Double-Blind Method; D005260:Female; D005746:Gastric Emptying / Q000502:physiology*; D005973:Glutamine / Q000008:administration & dosage* / Q000493:pharmacokinetics; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D011134:Polysaccharides / Q000008:administration & dosage* / Q000493:pharmacokinetics; D011897:Random Allocation; D012016:Reference Values; D013270:Stomach / Q000502:physiology / Q000648:ultrastructure*; D013997:Time Factors; D055815:Young Adult
chemical_list: D011134:Polysaccharides; D005973:Glutamine; C008315:maltodextrin