Viscometer microfluidic plasma viscosity reference interval rheology. Blood sampling for viscosity analysis can be performed as a standard procedure at room temperature. MicroVisc™ is suitable for measuring plasma viscosity in a clinical setting and results can be evaluated using the established reference range. Furthermore, sampling temperature at room temperature and 37☌ was investigated, and there was no difference in results obtained. A new reference range for the adult Danish population was established as 1.2-1.5 mPa s at 37☌.

The microfluidic-based viscometer performed well, and imprecision was comparable to ReoRox® G2 free oscillation rheometer. Most patients have symptoms when the relative viscosity is greater than 4 cP, but the relationship between serum viscosity and clinical manifestations is not precise. Hyperviscosity can precipitate or exacerbate heart failure. Sampling temperature was investigated by drawing and transporting blood at room temperature and 37☌ and comparing the viscosity between the two sampling methods. Dizziness, headache, vertigo, nystagmus, decreased hearing, ataxia, paresthesias, diplopia, somnolence, and coma may occur. The reference range was established for the adult population using EDTA-plasma from 120 healthy blood donors. The microVisc™ viscometer was evaluated for within-run and between-run imprecision and bias using standardized reference material (Paragon controls) and Seronorm™ control material.

Here, we investigate the performance of a new microfluidic-based viscometer for clinical use, establish a new reference range to be used with this instrument and determine the importance of sampling temperature. Plasma viscosity is an important biomarker both in diagnostics and treatment monitoring of plasma cell dyscrasias and other disorders with hyperviscosity syndrome as a clinical manifestation.

Blood viscosity tests