Lipaemic samples: effective process for lipid reduction using high speed centrifugation compared with ultracentrifugation.

Introduction: Reducing laboratory errors and improving patient safety is receiving a lot of attention. Lipaemic samples are cause of analytical errors and present challenges for laboratories, particularly for those without ultracentrifuges. Lipaemia can originate from physiological (postprandial metabolism), para-physiological causes (e.g. IV administration of lipids) as well as metabolic disturbances (e.g. hypertriglyceridaemia).

Materials And Methods: We have evaluated a procedure with 10 native lipaemic sample pools (triglyceride concentration range 11.6-42.7 mmol/L) for the ability to reduce lipid concentration using a high speed micro-centrifuge (double centrifuged at 21.885 x g for 15 min) compared with an ultracentrifuge, and provide accurate results. Results of sodium, creatinine, urate, total protein, lactate dehydrogenase (LD), magnesium and, cholesterol and triglyceride analysis on a Beckman DxC800 analyser are presented.

Results: Data from our tertiary level hospital showed approximately 0.7% of the samples received for lipid studies have triglyceride levels > 10 mmol/L which can potentially cause analytical interference. The mean differences from the neat aliquot to the ultracentrifuged and high speed centrifuged sample pools were: cholesterol 4.9 mmol/L and 3.1 mmol/L; and triglycerides 17.4 mmol/L and 15.0 mmol/L respectively. The data confirms high speed centrifugation is almost as effective as ultracentrifugation in lipid reduction.

Conclusion: The procedure utilized in this study using a high speed micro-centrifuge showed it is effective in reducing lipid levels and provides a suitable alternative to ultracentrifuged samples to provide accurate results.