Limited Interchangeability of Shunt-Side SpO₂ Measurements During Hemodialysis

Area of Science:

• Nephrology and Dialysis
• Cardiopulmonary Monitoring
• Medical Device Technology

Background:

• Current hemodialysis protocols measure oxygen saturation (SpO2) on the non-shunt side, limiting patient mobility.
• This limitation necessitates evaluating the feasibility of measuring SpO2 on the shunt side.

Purpose of the Study:

• To assess the interchangeability and agreement of SpO2 measurements taken on the shunt side versus the non-shunt side during hemodialysis.
• To determine if shunt-side SpO2 monitoring is a viable alternative in clinical practice.

Main Methods:

• A prospective, observational study involving 45 patients undergoing hemodialysis.
• Simultaneous, double-sided finger-sensor SpO2 monitoring was performed at five distinct time points.
• Statistical analyses included Lin's concordance correlation coefficient (CCC), Deming regression, Bland-Altman analysis, and accuracy root mean square (Arms).

Main Results:

• SpO2 measurements exhibited similar distributions between the shunt and non-shunt sides.
• High correlation (Spearman's ρ = 0.705) and concordance (CCC = 0.720) were observed.
• Bland-Altman analysis indicated minimal bias (0.060%) with limits of agreement of ±3%, and Arms of 1.41%.

Conclusions:

• Shunt-side SpO2 monitoring demonstrates potential acceptability in specific clinical scenarios during hemodialysis.
• Interindividual variability in measurements requires careful consideration.
• The findings are not generalizable to patients in hypoxic states (SpO2 < 90%).