REDUCTION OF THE PLASMA-LEVELS OF TISSUE PLASMINOGEN-ACTIVATOR AFTER INFUSION OF A LIPID EMULSION IN HUMANS

A lipid emulsion of soybean oil, egg lecithin, and glycerol, widely used as a standard component of parenteral nutrition regimens, has been reported to induce changes in some hemostatic parameters known to be associated with increased thrombotic risk. We studied the effect of a single infusion of this lipid emulsion (500 mL of a 10% emulsion, given over 5 to 6 hours) on the plasma levels of tissue plasminogen activator and plasminogen activator inhibitor 1 antigens in 12 patients with various diseases. Twelve matched patients, not treated with lipid, served as controls. In patients receiving the lipid emulsion, tissue plasminogen activator was markedly reduced at the end of the infusion (p < .001) and remained significantly lower than the basal levels 24 hours later (p < .05). By contrast, in control patients, the activator was slightly but significantly increased (p < .01) at the time interval corresponding to the postinfusion sample. Plasminogen activator inhibitor 1 was similar in control and treated patients at all intervals. The release of tissue plasminogen activator in response to 10 minutes of venous stasis, evaluated in six lipid-treated patients at the end of the infusion, was not different from that observed in six control patients. It is concluded that the lipid emulsion induces a marked decrease in the circulating levels of tissue plasminogen activator.