Comparison of Blood Gas Analysis and Auto-Analyzer Results for Sodium and Potassium Levels in Elderly and Non-elderly Adult Emergency Department Patients.

Objectives This study aims to evaluate the concordance between blood gas and biochemical measurement methods for sodium and potassium levels in elderly and non-elderly patients within an emergency department (ED) setting. Methods A retrospective method comparison study was conducted at an ED from February 1, 2023, to March 1, 2023. The study included 414 patients, categorized into "elderly" (aged 65 and above; n = 138, 33.3%) and "non-elderly" (aged 18 to 64; n = 276, 66.7%) groups. Concordance was assessed using Bland-Altman, Passing-Bablok, and Lin's concordance correlation methods. Results In sodium measurements, the elderly group exhibited an average bias of -1.52 mEq/L (95% confidence interval [CI] -2.12 to -0.92), with lower and upper limits of agreement (LoA) at -8.46 and 5.42 mEq/L, respectively, indicating a broader variance than non-elderly patients, who showed an average bias of -0.82 mEq/L with limits of -4.97 to 3.32 mEq/L. For potassium, the elderly group's average bias was -0.46 mEq/L (95% CI -0.36 to -0.57), with limits of agreement from -1.68 to 0.75 mEq/L, compared to non-elderly patients with a bias of -0.29 mEq/L and limits of -0.71 to 0.13 mEq/L. Furthermore, concordance correlation coefficients revealed a reduced agreement in the elderly for both sodium ( r _ccc = 0.799) and potassium ( r _ccc = 0.529) compared to the non-elderly cohort (sodium r _ccc = 0.821, potassium r _ccc = 0.715). Conclusion The study identifies significant discrepancies in sodium and potassium levels between elderly and non-elderly patients, suggesting a need for diagnostic precision. It emphasizes the importance of customizing diagnostic approaches to better serve the elderly population in EDs.
Competing Interests: Human subjects: Consent was obtained or waived by all participants in this study. Clinical Research Ethics Committee at Haseki Training and Research Hospital issued approval 122-2023. Ethical approval for this study was granted by the Clinical Research Ethics Committee at Haseki Training and Research Hospital on July 26, 2023, with the protocol number 122-2023. Animal subjects: All authors have confirmed that this study did not involve animal subjects or tissue. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work.
(Copyright © 2024, Tatliparmak et al.)