Non-Invasive Optical Quantification of Cerebral Tissue Oxygenation in Children with Single-Ventricle Congenital Heart Disease.

OBJECTIVE

To compare the accuracy of frequency-domain near-infrared spectroscopy (FD-NIRS) with clinically available optical measures of cerebral tissue oxygenation (StO2) and arterial saturation (SaO2).

STUDY

DESIGN

We enrolled 24 children with single-ventricle congenital heart defects scheduled for cardiac catheterization. Intraoperative FD-NIRS and continuous-wave near-infrared spectroscopy (CW-NIRS) measurements of StO2 were bilaterally obtained on the forehead. SaO2 was simultaneously acquired with FD-NIRS and pulse oximetry. Noninvasive StO2 and SaO2 were compared with invasive superior vena cava (SVC) and descending aorta saturation measurements. These measurements were also used to compute cerebral tissue oxygen extraction fraction (OEF).

RESULTS

The FD-NIRS StO2 was strongly correlated with invasive venous oxygen saturation (SvO2) (R = 0.74, P < .001; bias, -2.8%). However, correlation between CW-NIRS StO2 and invasive SvO2 was weaker and not significant (R = 0.29, P = .34; bias, -2.5%). Invasive SaO2 was correlated with FD-NIRS (R = 0.84, P < .001; bias, -3.2%) and pulse oximetry (R = 0.68, P = .001; bias, 0.2%) metrics of SaO2, but pulse oximetry showed larger error at low saturations. Finally, FD-NIRS OEF and invasive OEF were strongly correlated (R = 0.61, P = .01; bias, 0.09).

CONCLUSIONS

Our study suggests that FD-NIRS provides more accurate quantification of StO2 and SaO2 than CW-NIRS and pulse oximetry in patients with single-ventricle heart defects. We also demonstrated and validated stand-alone OEF quantification using FD-NIRS.