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Updated: Feb 4, 2026

Veno-Venous Extracorporeal Membrane Oxygenation in a Mouse
Published on: October 24, 2018
Retinal oxygen saturation as a non-invasive estimate for mixed venous oxygen saturation and cardiac output
Karel Van Keer1,2, Jan Van Keer3, João Barbosa Breda1,2,4
1Department of Ophthalmology, University Hospitals Leuven, Leuven, Belgium.
Purpose:
To investigate the correlation between retinal vessel oxygen saturation and mixed venous oxygen saturation (SvO2-mixed ) and cardiac output (CO).
Methods:
Retinal arterial (SaO2-retinal ) and venous (SvO2-retinal ) oxygen saturation were measured non-invasively with dual-wavelength retinal oximetry in subjects receiving invasive measurements of SvO2-mixed and CO through right heart catheterization. Correlations were analysed using Spearman's rank correlation coefficients and linear regression models.
Results:
Fourteen patients (median age 62.7 years, range: 21-77) were included in the analysis. When adjusted for age, SvO2-retinal showed a positive correlation with SvO2-mixed (β = 0.80, p = 0.003). Retinal arteriovenous oxygen saturation difference was significantly correlated with the inverse of CO (Spearman's ρ = 0.59, p = 0.026).
Conclusion:
This pilot study provides proof of concept for the use of retinal oximetry as a non-invasive tool to assess systemic cardiovascular function.
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