Discussion
Gastric emptying may be affected in critical illness and contributes to EN intolerance [16–19]. The use of GRV as a tool to evaluate gastric tolerance to EN is accepted as a clinical routine and has been incorporated in nutritional support algorithms in many ICUs [20, 21]. Our working hypothesis was that a limit higher than the 200–250-ml current limit could be used and that this could serve as a ‘‘rescue’’ mechanism for maintaining EN in patients with GRV in the range of 200–500 ml, without increasing complications. We decided to select a limit of 500 ml for GRV in the study group because this value has been suggested in the literature as a clinical end-point needing evaluation [10].