Correlation between GEM Premier 3000 and Vitros5.1+5600, SYSMEX XN-9000 in Detecting Electrolytes and Red Blood Cell Volume

Objective: To explore the consistency and relevance of the results of the bedside rapid blood gas analyzer GEM premier 3000, the Vitros5.1+5600 biochemical immunoassay analyzer and the SYSMEX XN-9000 automatic blood cell analyzer in the central laboratory detecting serum potassium (K+), serumsodium (Na+), blood glucose (Glu), hemoglobin (Hb) and red blood cell volume (Hct). And to provide a reference for the accurate interpretation of the bedside blood gas analysis report. Method: Usually, ICU patients will be taken arterial blood gas, biochemical and blood samples through the arterial indwelling needle;at the same time patients’ potassium, serum sodium, blood glucose, hemoglobin and red blood cell volume will be detected. This study implemented paired t-test and correlation regression analysis on each group of data, and used the analysis quality requirements (allowable total error) of CLIA’88 proficiency testing program as the criteria for clinical acceptance. Results: The paired t-test showed that the serum potassium, serum sodium and blood glucose detected by GEM premier 3000 and Vitros5.1+5600 were significantly different;and the hemoglobin and red blood cell volume detected by GEM premier 3000 and SYSMEX XN-9000 were significantly different (P < 0.05). The Pearson correlation coefficients (r) of hemoglobin, red blood cell volume and red blood cell volume were 0.860, 0.886, 0.924, 0.841 and 0.856, respectively, and the above test items all had good correlations (P < 0.05). The average (SE) of the paired differences of K+, Na+, Glu, Hb and Hct detected by the two sets of instruments is less than the allowable error of CLIA’88, and the SE of blood Na+ and Hb is less than half of the allowable error of CLIA’88. Conclusion: The test results of GEM premier 3000, the central laboratory Vitros5.1+5600 and SYSMEX XN-9000 have good correlation, but the consistency is not good. The test results of GEM premier 3000 cannot replace the central laboratory.

A new method to measure the concentration of argon-xenon gas mixture

RGAs are widely used in molec Background RGAs are widely used in molecular component examination,impurity analysis,leak detection and test of vacuum system performance.However,RGAs have different sensitivities to different gases,and the sensitivities can change quickly and depend on so many parameters,which make its ability severely limited.Methods In thiswork we established a newpractical method to precisely measure noble gas ratio of argon-xenon gasmixture.Gaseous argon and xenon were controlled,respectively,by two mass flow controller(MFC).A variable leak valve(VLV)was used to introduce the gas mixture sample into the RGA measurement chamber.Gas mixtures with xenon concentration from 200ppm to 20000ppm(by mass)were introduced and tested by RGA.Results The time stability of RGA-measurement system was optimized to 2.1%.A good linearity of MFC-RGA response was achieved,verifying the reliability of RGA in measuring noble gas mixture with component concentration down to several hundred ppm level.Conclusions Since the approach we used in our experiment is gas-species independent,we believe that it can be popularized to other gas species when properly applied.