Objective: To compare the cerebral tissue oxygenation index (TOI) measured by near-infrared spectroscopy (NIRS) with venous oxygen saturation in the jugular bulb (SjO(2)) during elective cardiac catheterization in children.
Design and setting: Prospective observational clinical study in a catheterization laboratory for pediatric cardiology.
Patients: Sixty children with congenital heart defects admitted to the catheterization laboratory.
Measurements and results: TOI measured noninvasively by NIRS was compared to SjO(2) measured in the jugular bulb during cardiac catheterization. Patients were divided into two groups regarding body weight: below (n=29) and above 10 kg (n=31). Linear regression analysis and Pearson's correlation coefficient were calculated. Bland-Altman analysis, sensitivity, and specificity calculation for spatially resolved near-infrared spectroscopy with a cutoff level of 60% were performed. Simultaneously measured values for SjO(2) (67.3+/-9.8%, 40-84.1%) and TOI (65.7+/-7.2%, 39-80%) showed a significant correlation; the correlation in children weighing under 10 kg was stronger in children weighing over 10 kg. Bland-Altman analysis showed a mean bias of -1.8% with limits of agreement between 11.7% and -15.3% for all children. Sensitivity and specificity of the SRS method were 46% and 91%, respectively, for all children and 53% and 83% respectively in infants weighing under 10 kg.
Conclusions: The results demonstrate that despite a significant correlation, sensitivity of spatially resolved spectroscopy is poor, and it is questionable whether TOI can be used reliably to detect low SjO(2).