By Todd W. Rice, MD
As we reported in Pulmonary Reviews, Todd W. Rice, MD, from Vanderbilt University School of Medicine, Nashville, and colleagues from the NIH ARDS Network conducted the EDEN trial—a randomized multicenter trial of 1,000 patients with acute lung injury—to determine if either trophic or full enteral feeding would reduce ventilator-free days or mortality. This research was presented at the Society of Critical Care Medicine’s 41st Critical Care Congress and also published in the February 22 JAMA. Rice elaborated on the study in his commentary below. (You can also listen to his audiocast.) Please weigh in with your opinion on the topic in the comments.
Mechanically ventilated patients are unable to provide for their own nutrition. Consequently, they are provided artificial nutrition, often in the form of enteral feeds. However, the optimal amount of enteral feeding to provide patients remains unknown, especially early in the critical illness.
The ARDS Network conducted a study comparing initial low dose—or trophic—enteral feeding versus early advancement to full-calorie enteral feeding for the first six days of mechanical ventilation. The study enrolled 1,000 patients with acute lung injury, requiring mechanical ventilation, and whose primary medical team intended to provide enteral nutrition.
Malnourished patients were excluded, as well as patients receiving parenteral nutrition or with contraindications to enteral nutrition. Over the first six days, patients randomized to the trophic group received an average of just under 400 calories per day compared to 1,300 calories in the full-feeding group.
Gastrointestinal intolerances, specifically higher gastric residual volumes, diarrhea, and vomiting were more frequent in the full-feeding group. Overall, there was no difference in the primary endpoint of ventilator-free days, or days both alive and free from mechanical ventilation between groups, with the trophic group having 14.9 and the full-feeding group 15.0. There was also no difference in 60-day mortality (23.2% in the trophic vs 22.2% in full-feeding groups), days alive and out of the ICU or hospital, or infectious complications.
Although not a classic non-inferiority study design, these results suggest that providing low-dose enteral feeds for up to the first six days in patients with acute lung injury results in similar outcomes to full enteral nutrition. Given this, time and effort can be focused away from getting enteral feeds to full-calorie rates and toward other aspects of care, which have been shown to improve clinical outcomes, such as lung protective ventilation and fluid management.