Intralipid removal from plasma of uraemic and intensive care patients

The removal rates from plasma of Intralipid and (125)I-albumin, simultaneously injected i.v., were analyzed in 10 chronic renal failure (CRF) patients. The results were compared with 9 intensive care unit (ICU) patients and five healthy subjects as controls. The fractional removal rates of Intralipid (k2) were significantly lower for the CRF patients compared to both ICU patients and healthy subjects. The initial plasma concentration of Intralipid, calculated by extrapolation of the elimination curve back to zero-time (y0), showed significantly higher values for CRF patients and healthy subjects compared to ICU patients. Removal curves expressed as ratios between Intralipid and (125)I-albumin paralleled the elimination curves for Intralipid, which suggests that the slope of the curves depends on Intralipid removal and not on leakage of macromolecules from the circulation. The very low initial plasma concentration of Intralipid in the ICU patients cannot be explained by a hyperdynamic circulation, but may be attributed to a rapid first passage disappearance of Intralipid from plasma into tissues such as the pulmonary vasculature.