Comparison between visual inspection of turbidity and quantitative determination of triglycerides in plasma bags

Abstract

ABSTRACT Introduction Blood donor screening is an important stage of quality control in blood banks. Turbidity caused by increased levels of triglycerides is detected by visual inspection, but there is no consensus on its threshold at which plasma should be considered inappropriate for donation. Objective Compare triglycerides dosage and visual turbidity in decision making for the disposal of plasma. Material and methods Plasma bags (n=205) were classified by visual inspection as clear, moderately turbid or turbid and triglyceride concentration were determined in serum and plasma with enzimatic-colorimetric methodology by automation. Results Our results show a positive correlation between serum and plasma triglycerides levels (r=0,94) but we observed a higher concentration in serum when compared to plasma samples (p<0,03). Most of the plasma were classified as moderately turbid or turbid (75%). Visual inspection and triglycerides levels were moderately correlated in serum (rb=0,57) and plasma (rb=0,52). However, moderately turbid samples showed discordance between serum or plasma triglyceride levels and the visual inspection. Discussion Our findings corroborate with the literature data, supporting the subjectivity of the visual inspection. We recommend further studies to determine which triglyceride threshold should be used for the disposal of plasma bags combined with automated methods to enhance visual classification accuracy. Conclusion Quality improvement actions are critical for standardization of the screening in order to avoid unnecessary disposal of the plasma bags.

Keywords

• triglycerides
• blood banks
• vision screening