Impact of Not Measuring Residual Gastric Volume on Nosocomial Pneumonia Rates in Mechanically Ventilated Patients Receiving Early Enteral Feeding: a Randomized-controlled Study

Early enteral feeding is a key component of the management of critically ill patients receiving mechanical ventilation. However, enteral feeding has been associated with serious complications such as aspiration followed by ventilator-associated pneumonia (VAP). Many critically ill patients experience poor tolerance of early enteral nutrition because of impaired gastric motility, which leads to a sequence of delayed gastric emptying, increased gastric volume, gastroesophageal reflux, vomiting, aspiration, and VAP. Routine monitoring of residual gastric volume (RGV) to minimize the risk of aspiration is standard practice. RGV is assumed to reflect gastric content, with high RGVs indicating impaired gastric emptying that requires discontinuation of enteral feeding in order to prevent aspiration.However, RGV measurement is neither standardized nor validated. The cut-off value that may indicate an increased risk of aspiration and therefore a need for discontinuing enteral feeding has not been determined, and cut-offs used in studies have ranged from 150 to 500 ml. No data are available to support a correlation between RGV and the rates of adverse events. In experimental studies, RGV failed to correlate with vomiting, aspiration, or VAP. The investigators hypothesize that RGV monitoring fails to decrease the risk of VAP and leed to inappropriate interruptions in enteral feeding with a risk of underfeeding. To assess the effects of not measuring RGV on VAP and enteral feeding delivery, the investigators designed a prospective randomized controlled study.