Abstract

Electrolyte problems are one of the most common cause of morbidity and mortality in the sick patients coming to the Emergency. Electrolytes measured in central lab usually takes 30-60 minutes or more whereas point of care device can give results within 5 to 10 minutes, however different instruments available and their values varies accordingly. Therefore, this study was done to investigate whether electrolyte i.e. sodium and potassium levels assessed using point of care device and auto analysers were equivalent. Methods: We prospectively studied patients admitted from Emergency Department between January 2021 to October 2021. We had taken 60 paired convenience samples and analysed sodium and potassium levels in point of care device (epoc POC device, Siemens) and in Central Lab Auto Analyser (Siemens Dimension RxL Max Integrated chemistry analyzer or in Johnson & Johnson chemistry analyser model number 51 FS). Statistical method to compare the data included Boxplot view, Regression line, Spearman’s correlation coefficient’s, paired t-test for potassium and Wilcox test for sodium correlation, Regression equation, Deming regression and Bland Altman plots. Results: The mean Sodium concentration in point of care device was 130.2 mmol/l and in Auto analyser was 130.5 mmol/l. The mean potassium level in point of care device was 4.013 mmol/l and in Auto analyser was 4.255 mmol/l. The Correlation coefficient obtained for sodium was 0.92 and for potassium was 0.818. Box plot view and regression line showed a good correlation. A difference above the CLIA criteria was noted for 10 pairs in sodium values and 07 pairs for potassium values. Conclusion: Point of care sodium and potassium values can be used in the Emergency Department for critical decision making.

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