A recent double-blind randomized study (NEJM 2018; 379: 1823-44) examined the outcomes of 3957 adult patients undergoing mechanical ventilation who received either a 1.5 kcal formula or 1.0 kcal formula for provision of enteral nutrition.
- While the volume of formula was similar, the 1.5 kcal group received a mean of 1863 kcal/day compared to 1262 kcal/day for the 1.0 kcal group.
- Yet, this did not translate into a survival benefit. By day 90, 26.8% of the 1.5 kcal group had died compared with 25.7% of the 1.0 kcal group (RR 1.05, 95% CI 0.94-1.16, P=0.41)
- Higher caloric delivery did not affect survival, receipt of organ support, duration of hospital stay, the incidence of infective complications or adverse events.
- Regurgitation was more common in the 1.5 kcal group: 18.9% vs 15.7%, RR 1.20, 95% CI 1.05-1.38)
- The 1.5 kcal group were more likely to receive promotility medications (47.4% vs 39.6%, RR 1.20)
- The 1.5 kcal group were more likely to receive insulin (55.8% vs 49.0%, RR 1.14)
In their discussion, the authors note that only 2% of patients had a BMI less than 18.5; thus, their cohort is unable to determine whether these patients could benefit from increased calories.
My take (borrowed in part from authors): “Increasing energy intake with the administration of energy-dense enteral nutrition did not affect survival among critically ill adults.” These types of studies are important in challenging assumptions that meeting calorie needs (with enteral or parenteral nutrition) will improve outcomes in hospitalized patients–though, this may be true in some populations.
Related blog posts:
- Detrimental Effect of Early Parenteral Nutrition in Critically-Ill Children The concept of providing early aggressive nutrition is NOT supported by this study
- Early versus late parenteral nutrition in critically ill adults