Safflower oil emulsion: single and multiple infusions with or without added heparin in normal human volunteers

Intravenous hyperalimentation in chronically ill patients has become increasingly common in hospitalized patients. Total parenteral nutrition includes supply of carbohydrates, amino acids, and lipids. The safety of a new emulsion of safflower oil (Liposyn 10%) infused by peripheral vein was evaluated in 15 normal male volunteers. All subjects tolerated Liposyn infusion, with a low incidence of side effects, when given either as a single infusion or multiple daily infusions to provide 4% of daily caloric requirements in the form of linoleic acid for 5 consecutive days. In large doses, the lipid infusion was accompanied by a decrease in Lee-White clotting time in most subjects, and 1.5 to 2 U/ml of heparin added to the emulsion reversed this effect. Such mini doses of heparin also accelerated the breakdown and disappearance of triglycerides, with a resultant increase in serum free fatty acids and cholesterol. These data suggest that safflower oil emulsion can be used as a source of essential fatty acids for intravenous alimentation. It is also suggested that patients receiving lipid infusion should receive heparin to minimize risks associated with hypercoagulability of blood.