This study aimed to investigate the effect of enteral feeding's macronutrient composition on inflammatory mediators, oxidative stress and outcomes in Intensive Care Unit (ICU) patients with acute respiratory failure. In this double-blind randomized control trial, 42 patients of both sexes and diagnosed with acute respiratory failure in ICU that receive enteral feeding, will be randomly assigned to three groups of 14 each. First Intervention group; high-protein low-carbohydrate diet with high olive oil, the second intervention group; high-protein low-carbohydrate diet with high sunflower oil and control; high-protein kitchen formula. Intravenous levels of uric acid, high sensitive C-Reactive Protein (hs-CRP), Interleukin 6 (IL-6) and Total Antioxidant Capacity (TAC) measured at days 0 and 10. As well as, organ failure, duration of ventilation, length of ICU stay and mortality rates will be evaluated.

Inclusion Criteria:

• enrolled in ICU
• age older than 18 years old
• need to be mechanically ventilation
• have enteral feeding
• no previous diabetes
• no previous HIV infection
• no previous nervous system
• no previous liver failure
• no previous nephrotic syndrome
• not passed more than 48 hours from diagnose of acute respiratory failure

Exclusion Criteria:

• death at less than three days of enteral feeding administration
• extubation at less than three days of enteral feeding administration