Assessment of pH and Oxygen Status during Hemodialysis Using the Arterial Blood Line in Patients with an Arteriovenous Fistula

Abstract

Background: In patients with arteriovenous fistulas, assessment of pH and oxygen status during hemodialysis (HD) using the extracorporeal dialysis arterial blood line is widely used both in daily routine and in most studies investigating hypoxia during HD. We designed this study to evaluate whether results of blood gas samples drawn from the extracorporeal arterial line were clinically acceptable in assessing oxygen status. Methods: We compared samples drawn from the extracorporeal arterial line with conventionally arterial punctures during 18 routine HD sessions. The samples were drawn simultaneously and analyzed immediately for blood gases, pH and hemoximetry values. Results: No significant difference was found between the values from the radial artery and the extracorporeal arterial blood line except for FMetHb. Conclusion: Thus, obtaining samples from the extracorporeal dialysis arterial blood line to evaluate the parameters of the oxygen status (pH, pO₂, pCO₂, ctHb, sO₂, FCOHb and ctO₂) during routine HD is a clinically convenient and accurate sampling approach.