Association between regional oxygen saturation and central venous saturation in pediatric patients undergoing cardiac...

We evaluated the correlation between regional oxygen saturation (rSO₂ ) in the frontal and right renal dorsum (cerebral rSO₂ and somatic rSO₂ ) measured by near-infrared spectroscopy (INVOS™ 5100C, Medtronic) and central venous oxygen saturation (ScvO₂ ) measured with a fiber-optic oximetry catheter (PediaSat™, Edwards Lifesciences) during surgery in order to determine whether noninvasive rSO₂ could be used as an alternative to ScvO₂ in pediatric cardiac surgery patients. We evaluated the correlation between regional tissue oxygen saturation (cerebral rSO₂ and somatic rSO₂ ) measured by near-infrared spectroscopy and other patient measures with central venous oxygen saturation (ScvO₂ ) measured with a fiber-optic oximetry catheter to track global oxygen supply demand as a potential alternative or supplement to ScvO₂ .

This single-center prospective observational study enrolled 33 children (weight < 10 kg) who underwent cardiac surgery for congenital heart disease between February 2018 and November 2021. ScvO₂ , cerebral rSO₂ , and somatic rSO₂ were recorded simultaneously after anesthesia induction and central venous catheter placement. Pearson's correlation coefficient and Bland-Altman analysis were used to determine the relationship between ScvO₂ and rSO₂ . We conducted correlation, Bland Altman, and multiple regression analyses to identify associations between rSO₂ , patient measures, and ScvO₂ values.

The patients' median age was 11.0 (quartile 2.0-16.0) months. Their weight was 7.2 (quartile 4.5-9.2) kg. Cerebral rSO₂ was significantly positively correlated with ScvO₂ (r²  = 0.29, p = .002 in all patients; r²  = 0.61, p = .013 in the patients without mixing at the atrial level), whereas somatic rSO₂ was not. The Bland-Altman analysis demonstrated biases [95% confidence interval; 95% CI] (lower and upper limits of agreement [95% CI]) of 0.27% [-4.26 to 4.80] (-24.79 [-32.61 to -16.96] to 25.33 [17.50 to 33.16]) between cerebral rSO₂ and ScvO₂ and 0.91% [-5.48 to 7.30] (-34.43 [-45.47 to -23.39] to 36.25 [25.21 to 47.29]) between somatic rSO₂ and ScvO₂ . Preoperative brain natriuretic peptide (BNP) and SpO₂ were independent variables associated with ScvO₂ and cerebral and somatic rSO₂ .

Cerebral rSO₂ , SpO₂ , and BNP were significantly correlated with ScvO₂ , although the cerebral rSO₂ correlation was greater for lesions without atrial mixing. rSO₂ , BNP, and SpO₂ might be used to track changes in ScvO₂ but cerebral rSO₂ is not sufficiently precise to replace it.