Benchtop centrifugation: An effective method for reducing lipaemia associated interference in grossly lipaemic samples?

Abstract

Background: Grossly lipaemic samples are a significant cause of analytical errors, potentially impacting patient care. The causes of lipaemia are varied and often unavoidable, while methods to reduce lipaemia through gold-standard ultracentrifugation are limited by availability, transportation and cost. Benchtop centrifugation has been proposed as an alternative method to reduce lipaemia.

Methods: Fifty-three grossly lipaemic serum samples (lipaemia >201.8 mg/dL) that were unsuitable for analysis were selected and centrifugated at 18840 g for different time-periods with lipaemia measured prior to and after centrifugation. Core analytes were measured on serum samples free of lipaemia before and after 30 min of centrifugation at 18840 g to assess the effect of the centrifugation process.

Results: After centrifugation for 5 min, 90% of grossly lipaemic samples were either ideal (lipaemia <50 mg/dL) or adequate (lipaemia 50.1-201.7 mg/dL) for analyte testing. All samples were either adequate or ideal for testing following centrifugation for 30 min. Although some analytes showed a statistically significant change in the measured concentration post high-speed centrifugation, none had clinically significant changes according to analyte specific reference change value (RCV) analysis. Aspartate aminotransferase (AST) and creatine kinase (CK) demonstrated the most notable reductions in activity, but these did not exceed their RCV.

Conclusions: Benchtop centrifugation shows potential laboratory utility in reducing lipaemia whilst maintaining clinically reliable results, however small sample sizes preclude firm conclusions. Further research is warranted to increase the sample size with finer time-point tuning, sub-group analysis and temperature analysis, due to the potential for sample heat injury, to balance practicality and accuracy.