Therapy with Omegaven will be provided at a dose of 1 gm/kg/day (by continuous infusion). Omegaven will be infused intravenously through either a central or peripheral catheter in conjunction with parenteral nutrition. Parenteral fat emulsion (Intralipid) will be administered only if necessary to administer adequate calories during Omegaven therapy. The same standards of care provided to all patients receiving parenteral nutrition solution will be followed.