Hospitalized mechanically ventilated patients are at higher risk of enteral underfeeding than non-ventilated patients.

Background & Aims: Enteral nutrition (EN) is the preferred method of nutrition support in hospitalized patients but only 50-90% of the required calories are actually delivered. In order to identify where our nutrition support team (NST) should focus its activity, we prospectively evaluated the level of coverage of energy and protein needs during the first 5 days of EN in intensive care unit (ICU) and non-ICU patients and the relationship of energy and protein coverage with serum albumin, transthryretin, insulin-like growth factor-1 (IGF-1) and C-reactive protein (CRP).

Methods: Subjects (n=183) who required nutrition support and received EN were prospectively recruited. Calorie prescription was 20 and 25, 25 and 30 kcal/kg BW for women and men 60 years and <60 years, respectively. Protein needs were estimated as 1.2g protein/kg BW. Logistic regression analysis was used to estimate odds ratios (OR) for energy and protein delivery 66.6% and <66.6% and albumin, transthryretin, IGF-1 (low vs. normal) and CRP (high vs. normal) in ventilated vs. non-ventilated patients.

Results: Significantly more mechanically ventilated than non-ventilated patients received <66.6% of energy (71% vs. 48%) and protein (96% vs. 65%). The ventilated patients were more likely to be energy (OR 2.1, CI 1.1-4.0) and protein (OR 15.7, CI 4.9-50.8) underfed than non-ventilated patients. There was a significant association on day 5 between low protein delivery and low albumin (OR 2.9, CI 1.3-6.5), low transthyretin (OR 3.0, CI 1.4-6.5), low IGF-1 (OR 2.8, CI 1.2-6.7) and high CRP (OR 3.5, CI 1.6-7.8).

Conclusions: The energy and protein needs of hospitalized patients are not met during the first 5 days of EN. Ventilated patients are more likely to be energy and protein underfed than non-ventilated patients and to have low plasma protein level. These findings support our decision to intensify EN monitoring by our NST in ventilated patients to optimize their nutritional coverage.