This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Saved Citations Download to citation manager Request Permissions Request Reprints Add to My Marked Citations Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Citing Articles via Scopus Google Scholar Articles by Chang, W.-K. Articles by Chao, Y.-C. Search for Related Content PubMed PubMed Citation Articles by Chang, W.-K. Articles by Chao, Y.-C. Social Bookmarking                         What's this?

Gastric Residual Volume (GRV) and Gastric Contents Measurement by Refractometry

Wei-Kuo Chang, MD, PhD^*, Stephen A. McClave, MD, Chung-Bao Hsieh, MD and You-Chen Chao, MD^*

From the ^* Division of Gastroenterology, Department of Internal Medicine, Tri-Service General Hospital, Taipei, Taiwan, Republic of China; Division of General Surgery, National Defense Medical Center, Taipei, Taiwan, Republic of China; and the Department of Medicine, University of Louisville School of Medicine, Louisville, Kentucky

Correspondence: You-Chen Chao, MD, Division of Gastroenterology, Tri-Service General Hospital, No. 325, Cheng-Kung Rd., Sec. 2, Neihu 114, Taipei, Taiwan. Electronic mail may be sent to weikuohome{at}hotmail.com.

Background: Traditional use of gastric residual volumes (GRVs), obtained by aspiration from a nasogastric tube, is inaccurate and cannot differentiate components of the gastric contents (gastric secretion vs delivered formula). The use of refractometry and 3 mathematical equations has been proposed as a method to calculate the formula concentration, GRV, and formula volume. In this paper, we have validated these mathematical equations so that they can be implemented in clinical practice. Methods: Each of 16 patients receiving a nasogastric tube had 50 mL of water followed by 100 mL of dietary formula (Osmolite HN, Abbott Laboratories, Columbus, OH) infused into the stomach. After mixing, gastric content was aspirated for the first Brix value (BV) measurement by refractometry. Then, 50 mL of water was infused into the stomach and a second BV was measured. The procedure of infusion of dietary formula (100 mL) and then water (50 mL) was repeated and followed by subsequent BV measurement. The same procedure was performed in an in vitro experiment. Formula concentration, GRV, and formula volume were calculated from the derived mathematical equations. Results: The formula concentrations, GRVs, and formula volumes calculated by using refractometry and the mathematical equations were close to the true values obtained from both in vivo and in vitro validation experiments. Conclusions: Using this method, measurement of the BV of gastric contents is simple, reproducible, and inexpensive. Refractometry and the derived mathematical equations may be used to measure formula concentration, GRV, and formula volume, and also to serve as a tool for monitoring the gastric contents of patients receiving nasogastric feeding.

Journal of Parenteral and Enteral Nutrition, Vol. 31, No. 1, 63-68 (2007)
DOI: 10.1177/014860710703100163


CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?

This article has been cited by other articles:

				N. M. Mehta Approach to Enteral Feeding in the PICU Nutr Clin Pract, June 1, 2009; 24(3): 377 - 387. [Abstract] [Full Text] [PDF]

				T. V. Moreira and M. McQuiggan Methods for the Assessment of Gastric Emptying in Critically Ill, Enterally Fed Adults Nutr Clin Pract, April 1, 2009; 24(2): 261 - 273. [Abstract] [Full Text] [PDF]

				N. A. Metheny, L. Schallom, D. A. Oliver, and R. E. Clouse Gastric Residual Volume and Aspiration in Critically Ill Patients Receiving Gastric Feedings Am. J. Crit. Care., November 1, 2008; 17(6): 512 - 519. [Abstract] [Full Text] [PDF]