Gastric residual volume by magnetic ressonance after intake of maltodextrin and glutamine: a randomized double-blind, crossover study.

CONTEXT The addition of glutamine in preoperative drinks may enhance the benefits of carbohydrate alone. OBJECTIVES To evaluate the gastric residual volume after the intake of a beverage containing carbohydrate plus glutamine. METHODS Eleven healthy volunteers (24-30 years-old) were randomized in a crossover fashion to intake 400 mL (4h before) and 200 mL (2h before) of a beverage containing either 12.5% maltodextrin (carbohydrate group) or 12.5% maltodextrin plus 15 g of glutamine (glutamine group) in two different moments 7 days apart. Magnetic ressonance was performed to measure the gastric residual volume (mL) 120 and 180 minutes after the last ingestion. RESULTS Gastric residual volume similar to basal condition was found after 2h and 3h of the intake of beverages. There was no difference in the mean ±SD GRV (mL) found at 120 minutes (carbohydrate group: 22.9±16.6 and glutamine group: 19.7±10.7) and at 180 minutes (carbohydrate group: 21.5±24.1 and glutamine group: 15.1±10.1) between the two drinks. CONCLUSIONS Gastric emptying is efficient, and occurs in up to two hours after the intake of a beverage containing either carbohydrate alone or carbohydrate associated with glutamine. The addition of glutamine to carbohydrate-enriched drink seems to be safe for the use up to 2h before an operation.