The Effects on Gastric Emptying and Carbohydrate Loading of an Oral Nutritional Supplement and an Oral Rehydration Solution: A Crossover Study with Magnetic Resonance Imaging

Nakamura, Makoto MD*; Uchida, Kanji MD, PhD*; Akahane, Masaaki MD, PhD; Watanabe, Yasushi; Ohtomo, Kuni MD, PhD; Yamada, Yoshitsugu MD, PhD*

doi: 10.1213/ANE.0b013e3182a9956f
Critical Care, Trauma and Resuscitation: Research Report

BACKGROUND: Preoperative administration of clear fluids by mouth has recently been endorsed as a way to improve postoperative outcomes. A carbohydrate-containing beverage supplemented with electrolytes or proteins may have additional benefits for patients’ satisfaction. However, effects on gastric residual, nausea, and emesis and the effectiveness of these beverages for improving patients’ hydration status have not been well defined.

METHODS: We evaluated changes in gastric volume over time by magnetic resonance imaging, as well as blood glucose levels, before and after administration of 500 mL oral rehydration solution (ORS) containing 1.8% glucose and electrolytes in 10 healthy volunteers. The same volume of an oral nutritional supplement (ONS) containing 18% glucose and supplemental arginine (545 mOsm/kg) was given to the same population using a crossover design.

RESULTS: The mean (median, 95% confidence interval) gastric fluid volume at 1 hour after oral ingestion was 55.0 (55.3, 39.0–70.9) mL in the ORS group, whereas 409.2 (410.9, 371.4–447.0) mL in the ONS group (P = 0.0002). The gastric fluid volume of all participants in the ORS group returned to <1 mL/kg at 90 minutes after ingestion, whereas none reached <1 mL/kg at 120 minutes in the ONS group. The ONS group showed a sustained increase in the blood glucose level after ingestion (P < 0.0001 to baseline at 30, 60, 120 minutes), while the ORS group showed an initial increase (P < 0.0001, P = 0.01, P = 0.205 at each time point).

CONCLUSIONS: ORS supplemented with a small amount of glucose showed faster gastric emptying, which may make it suitable for preoperative administration. In contrast, ONS supplemented with arginine with a relatively low osmolality was associated with a longer time for gastric emptying, although it showed a sustained increase in blood glucose level.

Published ahead of print December 31, 2013

From the Departments of *Anesthesiology and Pain Relief Center and Radiology, The University of Tokyo Hospital, Tokyo, Japan.

Accepted for publication August 13, 2013.

Published ahead of print December 31, 2013

Funding: a Grant-in-Aid for Scientific Research A from the Ministry of Education and Science (No. 23249072, YY, KU), and a Grant-in-Aid for Scientific Research B from the Ministry of Education and Science (No. 24390364,KU). A Grant for “Rare Lung Diseases” from the Ministry of Health Labour and Welfare (H24-Nanchitou [Nanchi]-Ippan-035, KU).

Conflict of Interest: See Disclosures at the end of the article.

This report was previously presented, in part, at the 32nd Annual Meeting of the Japan Society of Clinical Anesthesia.

Reprints will not be available from the authors.

Address correspondence to Kanji Uchida, MD, PhD, Department of Anesthesiology and Pain Relief Center, The University of Tokyo Hospital. 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan. Address e-mail to

© 2014 International Anesthesia Research Society