Comparative Study About the Impact of Two Oil Emulsions Administered Intravenously on Severe Acute Pancreatitis

Inclusion Criteria: * Diagnosis of acute pancreatitis: characteristic abdominal pain, serum amylase and / or lipase \>= 3 times the upper limit of normal range, characteristic CT-scan * Criteria of severity of acute pancreatitis diagnosed at \<= 72 hours following admission: severity Index of Balthazar's CT-scan (with contrast) \>= grade D, APACHE-II \>= 8, C-reactive protein \>= 150 mg/L * Inability to initiate feeding (oral or with nutritional supplements) and / or enteral nutrition during the 5 days after the diagnosis and prediction of the indication of nil-by-mouth \>= 5 days * \<= 3 mmol/L of triglycerides in the blood * Men and women aged \>= 18 years old * Acceptance of informed consent Exclusion Criteria: * Known hipersensitivity to the fish, egg or soy proteins * Lipid etiology * \> 3 mmol/L of triglycerides in the blood * Severe hepatic impairment * Severe renal insufficiency without dialysis or haemofiltration * Serious disturbances of blood clotting * Acute shock * Infusion therapy general contraindications * Clinical conditions of instability that must not be taken with parenteral nutrition * Have other acute or chronic inflammatory diseases * Status of severe immunosuppression: cytotoxic treatment in 15 days prior to inclusion and / or a disease that causes white blood cells levels \<5000/mm3 * Treatment with steroids \> 0.25 mg/kg/day of prednisone or equivalent doses of corticosteroids: as pre-treatment and / or during admission