Not Monitoring Stomach Fluid Volume for Patients on Ventilator Does Not Increase Risk of VAP

Patients undergoing mechanical ventilation and receiving nutrition via a feeding tube who did not receive monitoring of residual gastric volume were not at a significantly greater risk of developing ventilator-associated pneumonia (VAP), according to a study appearing in the Jan. 16 issue of JAMA. There is concern that monitoring of residual gastric volume leads to unnecessary interruptions of use of the feeding tube and subsequent inadequate feeding.
 
Early enteral nutrition is the standard of care in critically ill patients receiving invasive mechanical ventilation. However, numerous studies have shown that early enteral nutrition is frequently not used or associated with inadequate calorie delivery, according to background information in the article. The main reason for non-use is gastrointestinal intolerance to enteral nutrition. Monitoring of residual gastric volume is recommended to prevent ventilator-associated pneumonia (VAP) in patients receiving early enteral nutrition. However, studies have challenged the reliability and effectiveness of this measure.
 
Jean Reignier, MD, PhD, of the District Hospital Center, La Roche-sur-Yon, France and colleagues conducted a study to test the hypothesis that absence of residual gastric volume monitoring was not associated with an increased incidence of VAP compared with routine residual gastric volume monitoring. The randomized, noninferiority (outcome not worse than treatment compared to) trial was conducted from May 2010 through March 2011 in adults requiring invasive mechanical ventilation for more than 2 days and given enteral nutrition within 36 hours after intubation at 9 French intensive care units (ICUs); 452 patients were randomized and 449 included in the intention-to-treat analysis (3 withdrew initial consent). The intervention for this study was the absence of residual gastric volume monitoring.
 
The researchers found that in the intention-to-treat population, VAP occurred in 38 of 227 patients (16.7 percent) in the intervention group and in 35 of 222 patients (15.8 percent) in the control group. Patients in the intervention group were 77 percent more likely to receive 100 percent of their calorie goal than patients in the control group. Absence of residual gastric volume monitoring was not inferior to residual gastric volume monitoring regarding new infections, intensive care unit and hospital stay lengths, organ failure scores, or mortality rates.
 
In conclusion, the current study supports the hypothesis that a protocol of enteral nutrition management without residual gastric volume monitoring is not inferior to a similar protocol including residual gastric volume monitoring in terms of protection against VAP. Residual gastric volume monitoring leads to unnecessary interruptions of enteral nutrition delivery with subsequent inadequate feeding and should be removed from the standard care of critically ill patients receiving invasive mechanical ventilation and early enteral nutrition, the authors write.

Reference: JAMA. 2013;309(3):249-256.
 
Editors Note: The Centre Hospitalier Departemental de la Vendee was the study sponsor. All authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflict of Interest and none were reported.
 
Editorial: Gastric Residual Volume - End of an Era
 
Todd W. Rice, M.D., M.Sc., of the Vanderbilt University School of Medicine, Nashville, Tenn., comments on the findings of this study in an accompanying editorial.
 
Despite emerging evidence to the contrary, many enteral feeding protocols continue to interrupt enteral feeding for relatively low gastric residual volumes (GRVs), some with thresholds as low as 150 mL or twice the enteral feeding rate the patient is receiving at the time. The finding from the study by Reignier et al should instill confidence in clinicians to change practice and not routinely check GRVs in all patients mechanically ventilated receiving enteral nutrition.
(JAMA. 2013;309(3):283-284;