Volume-Based Feeding in the Critically Ill Patient

Introduction: Critically ill patients placed on enteral nutrition (EN) are usually underfed. A volume-based feeding (VBF) protocol designed to adjust the infusion rate to make up for interruptions in delivery should provide a greater volume of EN than the more common fixed hourly rate-based feeding (RBF) method. Methods: This single-center, randomized (3:1; VBF/RBF) prospective study evaluated critically ill patients on mechanical ventilation expected to receive EN for ‰3 days. Once goal rate was achieved, the randomized feeding strategy was implemented. In the VBF group, physicians used a total goal volume of feeds to determine an hourly rate. For the RBF group, physicians determined a constant hourly rate of infusion to meet goal feeds. Results: Sixty-three patients were enrolled in the study with a mean age of 52.6 years (60% male). Six patients were excluded after randomization because of early extubation. The VBF group (n = 37) received 92.9% of goal caloric requirements with a mean caloric deficit of 776.0 kcal compared with the RBF group (n = 20), which received 80.9% of goal calories (P =.01) and a caloric deficit of 1933.8 kcal (P =.01). Uninterrupted EN was delivered for 51.7% of all EN days in VFB patients compared with 54.5% in RBF patients. On days when feeding was interrupted, VFB patients overall received a mean 77.6% of goal calories (while RBF patients received 61.5% of goal calories, P =.001). No vomiting, regurgitation, or feeding intolerance occurred due to VBF. Conclusions: A VBF strategy is safe and improves delivery to better meet caloric requirements than the standard more commonly used rate-based strategy.