title: Should enteral nutrition be started in the first week of critical illness?
abstract: OBJECTIVE
  To review the mechanistic evidence for early enteral nutrition in critically ill patients within the first week of ICU admission.
  
  
  RESULTS
  There is a lack of recent large randomized controlled trials showing clinically important outcome benefits related to early enteral nutrition. Most supporting studies are based on the animal models, and explore mechanisms of benefit related to gut immunity and oxidative stress. In addition, the impact of nutrient deprivation on the microbiome recently shown in a human trial is compelling. Large randomized controlled clinical trials have emerged in the last 2 years, however, comparing minimal enteral nutrition therapy and enteral nutrition versus parenteral nutrition. They call into question the low quality of clinical evidence and the widespread support for early enteral nutrition as a primary recommendation. As a result, the questions of whether or not enteral nutrition should be initiated in the first week versus standard of care or parenteral nutrition and how clinicians justify this recommendation are raised.
  
  
  CONCLUSIONS
  Despite the wide range of quality in the current clinical outcomes evidence, early enteral nutrition within the first week of ICU admission, delivered to the appropriate patient, promotes gut-mediated immunity, lowers metabolic response to stress, maintains microbial diversity, and improves clinical outcomes versus standard of care or parenteral nutrition therapy.
authors: aDivision of General Surgery, Hospital Nutrition Services, Oregon Health and Science University bDepartment of Surgery, Oregon Health and Science University cPortland VA Healthcare Center, Portland, Oregon, USA.
authors: Robert G
authors: RG
authors: Martindale
authors: Malissa
authors: M
authors: Warren
mesh_terms: D016638:Critical Illness / Q000628:therapy*; D004750:Enteral Nutrition / Q000379:methods*; D006760:Hospitalization; D006801:Humans; D007362:Intensive Care Units; D010288:Parenteral Nutrition; D016032:Randomized Controlled Trials as Topic; D059039:Standard of Care; D013997:Time Factors; D016896:Treatment Outcome