Utilization of fat emulsion during total parenteral nutrition in children.

Tolerance for Intralipid fat emulsion during total parenteral nutrition (PN) was studied in 6 children. The Intralipid dose was monitored by the daily determination of plasma Intralipid levels. Fat removal was investigated at the start of and during the PN period by the intravenous fat tolerance test (IVFTT) and by determining the plasma postheparin lipoprotein lipase (LPL) activity. When the plasma Intralipid levels exceeded a value of 100 mg/100 ml, hyper pre-beta lipoproteinaemia, hypertriglyceridaemia, hypercholesterolaemia and hyperphospholipidaemia appeared. During PN most patients showed marked increases of postheparin LPL. Return to normal values occurred after discontinuation of PN. Maximal LPL activities were found to correlate significantly with total daily caloric intake (r=0.95, 0.05 less than p less than 0.01). The Intralipid elimination constant hardly changed during PN, with the exception of patient 6, who showed a marked increase (from 7 to 22%). Conclusions of this study are as follows: First a high caloric intake during PN leads to a marked increase of postheparin LPL activity. Second, by monitoring plasma Intralipid levels at 100 mg/100 ml approximately, it is possible to adjust the Intralipid dose in order to prevent hyperlipaemia and to take maximal benefit from rising fat tolerance. Thirdly the IVFTT appeared to be of little value to estimate the child's fat elimination capacity.