120 as the supply of such analyzers increases. The aim of the study was to evaluate existing point-of-care arterial blood gas analyzers for electrolyte measures. The instrumental difference between the AA and the ABG analyzers is the turnaround time to get the results. Also the fact that blood gas analyzers are unaffected by serum protein levels in their electrolyte measures is an added advantage to using them as a point-of-care electrolyte measure in critically ill patients [16, 17]. Despite the differences that have been cited in the working of the ABG machine and the AA, this study shows that there are no significant differences between the K+ measured by the AA and the ABG machines. The authors therefore suggest that decisions based on serum K+ can be made by trusting the value obtained on the ABG machine. The study agrees with previous studies [6] that Na+ values obtained on the ABG machine are not completely reliable when making clinical decisions. Though statistical- ly significant, the difference in the measured Na+ values in hypernatremic and normo-natremic patients was within the recommended US CLIA guidelines. Whether statistical difference also translates to clinical difference remains to be seen. Some of the limitations of our study are that the results are limited to the use of one AA and one ABG machine. However, previous studies comparing blood gas analyzers of different brands have shown that the measures obtained from ABG machines are highly statistically concordant [18]. Another limitation was that the ABG samples were collected using conventional syringes containing liquid heparin. The use of dried heparin syringes [9] could improve the accuracy of the results by decreasing the dilution of the sample. Previous studies referenced earlier have shown that ABG machines do not measure electrolytes accurately, but since all these studies compared results between AA and ABG analyzers in different environments, we created another limitation for ourselves by locating the ABG analyzer in the central laboratory in an environment similar to the AA, and in doing so we did undermine the true meaning of point-of-care testing, which is often equated to bed-side testing. However, the time gain was significant even by following the above practice since the time for analysis itself was minimized. In conclusion, we advocate the use of ABG machines for adjudging serum potassium values accurately, in the absence of other specialized point-of-care analyzers. Fur- ther research is needed to establish their accuracy for sodium values. Int J Emerg Med (2009) 2:117–120 Conflicts of interest None. References 1. Price CP (2002) Medical and economic outcomes of point of care testing. 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