The primary objective is to assess the effect of fish oil-enriched enteral and parenteral nutrition on blood oxygenation in critically ill patients.

Inclusion: - signed informed consent

• mechanically-ventilated adults (age 18-80) admitted to Intensive Care Unit,
• enteral nutrition does not meet the nutrition goal (at least 80 % of the resting energy expenditure) within the past 36 hours
• APACHE II score above the median value of the intensive care unit (id est > 20)

Exclusion: - do not resuscitate status

• cardiogenic pulmonary edema
• previous (< 1 month) or ongoing need for corticosteroids > 0.1 mg/kg prednisolon- equi-valent or other immune suppressive treatment
• serum triglycerides > 300 mg/dl at screening
• alterations of coagulation (platelets <100.000 mm3), PTT > 60 sec, INR ≥ 2.5 without therapeutic intervention
• pregnancy
• participation in a clinical study with an investigational drug within one month prior to the start of this clinical trial
• known or suspected drug abuse
• general contraindications for infusion therapy such as acute pulmonary oedema, hyper-hydration and decompensated cardiac insufficiency
• known hypersensitivity to egg-, soy-, and fish proteins or any of the ingredients
• autoimmune disease or HIV
• uncompensated hemodynamical failure of any origin (hemorrhagic shock, myocardial infarction, cardiac failure)
• uncompensated ketoacidosis caused by Diabetes mellitus within 7 days prior to onset of study
• uncompensated renal insufficiency with serum creatinine > 1.5 mg/dL (> 133 µmol/L)
• patients with severe liver dysfunction with bilirubin > 2.5 mg/dL (> 43 µmol/L)
• necrotizing pancreatitis