acid-rich vegetable oil-based enteral and parenteral nutrition is still widely used, newer lipid 53 components such as medium-chain triglycerides and olive oil are safe and well tolerated. Fish 54 oil (FO)-enriched enteral and parenteral nutrition appears to be well tolerated and confers 55 additional clinical benefits, particularly in surgical patients, due to its anti-inflammatory and 56immune-modulating effects. Whilst the evidence base is not conclusive, there appears to be a 57 potential for FO-enriched nutrition, particularly administered peri-operatively, to reduce the rate 58 of complications and intensive care unit (ICU) and hospital stay in surgical ICU patients. The 59 evidence for FO-enriched nutrition in non-surgical ICU patients is less clear regarding its clinical 60 benefits and additional, well-designed large-scale clinical trials need to be conducted in this 61 area. The ESPEN Expert Group supports the use of olive oil and FO in nutrition support in 62 surgical and non-surgical ICU patients but considers that further research is required to provide 63 a more robust evidence base. 64 65 Page 4 of 77 Nutrition support of the critically ill patient 66Patients in an intensive care unit (ICU) are heterogeneous and include surgical and medical 67 patients, mechanically-ventilated or non-ventilated, obese or undernourished, preterm infants to 68 older adults, requiring either short-term or long-term intensive care [1]. Nutrition support is 69 critical in maintaining homeostasis in the ICU patient and to provide nutrients for the 70 maintenance of lean body mass as well as repair and maintenance of organ function and 71 support of defense and healing processes. 72Enteral nutrition (EN) comprises specialized liquid nutrition delivered through a nasogastric or 73 post-pyloric feeding tube into the stomach or small intestine (duodenum/jejunum), respectively 74[2]. The European Society for Clinical Nutrition and Metabolism (ESPEN) guidelines recommend 75 that EN should be given to all ICU patients who are not expected to be taking a full oral diet 76 within three days [3]. 77Whilst ESPEN acknowledges that there are no definitive data supporting the early use of EN in 78 terms of clinical outcomes, its guidelines recommend that hemodynamically stable critically ill 79 patients who have a functioning gastrointestinal tract should be fed early (< 24 hours) using an 80 appropriate amount of feed [3]. Early initiation of EN is also recommended by the American 81 Society for Parenteral and Enteral Nutrition (ASPEN) and the Canadian Society of Critical Care 82Medicine (SCCM) [4], as well as the European Society of Intensive Care Medicine (ESICM) [5]. 83Administration of early EN in critically ill patients appears to also have a positive economic 84 impact, with analysis suggesting that it is associated with significantly reduced costs relating to 85 reduction in ICU stay and duration of mechanical ventilation compared with standard care [6]. 86There are a number of nutritional and non-nutritional benefits associa...

Gastrointestinal complications are less frequent in ICU patients fed in the jejunum. Nevertheless, it seems to be a necessary learning curve to achieve better results with a postpyloric access. Early enteral nutrition using a nasojejunal route seems not to be an efficacious measure to decrease nosocomial pneumonia in critically ill patients.