Use of Omega 3 Oil Emulsion for Parenteral Nutrition Associated Cholestasis

Inclusion Criteria: 1. Age \< 18 years old 2. Patients will be PN dependent (unable to meet nutritional needs solely by enteral nutrition) and are expected to require PN for at least another 30 days, may be inpatient or outpatient 3. Patients considered eligible for study participation must have parenteral nutrition associated liver disease (PNALD) as defined as a direct bilirubin of 2 mg/dl or more. Other causes of liver disease should be excluded. A liver biopsy is not necessary for treatment 4. Direct bilirubin \> 2.0 mg/dl 5. Signed patient informed consent 6. The patient must have utilized standard therapies to prevent the progression of his/her liver disease including surgical treatment, cyclic PN, avoiding overfeeding, reduction/removal of copper and manganese from PN, advancement of enteral feeding, or the use of ursodiol (i.e., Actigall®) Exclusion Criteria: 1. Pregnancy 2. Other causes of chronic liver disease (Hepatitis C, Cystic fibrosis, biliary atresia, and alpha 1 anti-trypsin deficiency) 3. Enrollment in any other clinical trial involving an investigational agent (unless approved by the designated physicians on the multidisciplinary team) 4. The parent or guardian or child unwilling to provide consent or assent 5. Patients known to be allergic to fish or egg protein and patients with the following contraindications to Omegaven™ use: * Impaired lipid metabolism * Severe hemorrhagic disorders * Unstable diabetes mellitus * Collapse and shock * Stroke/embolism * Recent cardiac infarction * Undefined coma status