Effects of high-dose, intravenous lipid emulsion on laboratory tests in humans: A randomized, placebo-controlled, double-blind, clinical crossover trial

Background Intravenous lipid emulsion (ILE) is used to treat drug poisonings. The resultant hyperlipemia may affect laboratory tests but the consequences are poorly characterized. In a clinical trial we therefore investigated the effects of ILE on laboratory tests analyzed on common analytical platforms (Roche® cobas 8000 and SYSMEX® flow-cytometry). Methods Ten healthy participants each completed 4 trial days (two with ILE and two with placebo). ILE (5.25 mL/kg) was administered from 12.5 to 30 min from baseline. At 0, 30 and 60 min, blood samples were drawn for measurement of 20 analytes. We investigated the effects of ILE on analyte levels and frequencies of exceedance of predefined analyzer hemolysis (H) or lipemia (L)-index cut-offs and test-specific reference change values (RCVs) on ILE-days. If the results were blocked due to exceedance of index values, we manually extracted the results. Results Sixteen out of 20 tests were blocked because H- or L-index cut-offs were exceeded on ILE-days. Differences in analyte levels between ILE- and placebo-days above the RCV were observed for aspartate aminotransferase, total calcium, lactate dehydrogenase (LDH), sodium and neutrophils. Mean values outside the normal range after ILE were observed for LDH (219 U/L), sodium (135.3 mmol/L) and total calcium (2.1 mmol/L). Conclusions ILE-infusion caused report failure of nearly all laboratory tests performed on a cobas 8000-platform, but it was possible to manually retrieve the results. For most test results - particularly alkaline phosphatase, bilirubin, phosphate and carbamide - the consequences of ILE were marginal, and the effects of ILE were reduced at the 60-min timepoint.