Original Article

Comparison of Hgb, Htc, Na+, and K+ Levels Measured by Blood Gases Analyzer and Laboratory Auto-Analyzer in Different pH Stages


  • Seref Kerem Corbacioglu
  • Emine Emektar
  • Yunsur Cevik
  • Seda Dagar
  • Hikmet Sencanlar Cetiner
  • Mehmet Ali Ozbek
  • Sedat Akkan

Received Date: 21.05.2018 Accepted Date: 28.06.2018 Eurasian J Emerg Med 2018;17(4):159-164


The primary aim of the present study was to detect whether blood gases analyzer (BGA) is reliable or not in daily practice by comparing sodium (Na+), potassium (K+), hemoglobin (Hgb), and hematocrit (Htc) levels measured by BGA and laboratory auto-analyzer (LAA). The secondary aim was whether BGA is reliable or not in daily practice by comparing Na+, K+, Hgb, and Htc levels measured by BGA and LAA in different pH stages.

Materials and methods:

The study screened the electronic data and file records of all patients who were admitted to the emergency department with any complaint during the study period retrospectively. Patients who had results of venous blood gases and routine laboratory obtained at the same time were included the study. For each parameter, agreements and correlations between the results of BGA and LAA were evaluated by Bland-Altman test and Spearman’s correlation test, respectively. An r-value >0.80 was considered a strong correlation.


The laboratory results of 1374 patients were evaluated for statistical analyses. When evaluating the correlations between the results of BGA and LAA, it was found that there was only a strong correlation for K+ (p<0.001, r=0.83). When assessing the agreements between the results of BGA and LAA, the mean differences were found to be 0.02±6.1 for Na+, 0.3±0.44 for K+, -0.5±1.6 for Hgb, and -0.6±5 for Htc.


Although there are strong correlation and relatively good acceptable agreement for K+ measurement, there are no strong correlation and good agreement for other measurements, including Na+, Hgb, and Htc. In addition, we found that these results did not change according to the different pH stages.

Keywords: Blood gases analysis, venous blood gases, potassium, sodium, hemoglobin, hematocrit