Clinical use of gastric residual volumes as a monitor for patients on enteral tube feeding.

BACKGROUND: The use of gastric residual volumes (GRVs) as a clinical monitor for patients receiving enteral tube feeding (ETF) is based on presumptions that are not physiologically sound and practice that is poorly standardized.
METHODS: This systematic review of the medical literature summarizes results from studies that evaluate the practice, interpretation, and impact on patient outcome from use of GRV.
RESULTS: Little data exist to support a correlation of GRV with gastric emptying, volume of gastric contents, or changes in the infusion of ETF. GRVs do not correlate to regurgitation or aspiration, and their use cannot be relied on to protect patients against aspiration pneumonia. Although recent reports suggest that elevated GRVs correlate to "intolerance" of ETF, use as a marker of impending clinical deterioration is limited by the fact that the timing of increases in GRV is unpredictable and high GRVs do not correlate independently to adverse outcome. The practice of GRV may in fact impede delivery of ETF by promoting inappropriate cessation and reducing potential infusion time.
CONCLUSIONS: Modifying interpretation and the response by healthcare providers to GRV data are needed to preserve any clinical use for this practice.