We propose to conduct a randomized controlled clinical trial to determine whether the use of an omega-3 fatty acid based IFE in infants with surgical gastrointestinal disease will improve clinical outcomes compared to infants treated with standard IFE up to 6 months post randomization. Neonates and infants < 3 months old (postnatally) with surgical gastrointestinal disease (defined as congenital or acquired gastrointestinal disease requiring PN for more than 21 days) will be eligible for enrollment. Patients who meet all inclusion and exclusion criteria will be randomized to receive PN with either Intralipid® or Omegaven®. The appearance of both IFEs is indistinguishable, so patients, families and the medical care team will be blinded to treatment group allocation. Aside from the IFE type, the clinical care of both groups of infants will remain unchanged, including standard use of feeding advancement protocols, and treatment of underlying gastrointestinal and other diseases.