Cerebral regional oxygen saturation monitoring in pediatric malfunctioning shunt patients

Abstract

Background: Shunt malfunction produces increased intracranial pressure causing decreased cerebral regional perfusion and tissue O(2)sat. Cerebral regional oxygen saturation (rSO(2)) by near-infrared spectroscopy represents tissue perfusion and oxygen saturation. Cerebral rSO(2) is used to detect cerebral ischemia in pediatric clinical settings.

Objective: The objective of the study was to determine the reliability of cerebral rSO(2) in pediatric malfunctioning shunt.

Methods: A prospective observational study of pediatric patients presented to the pediatric emergency department was conducted. Confirmed malfunctioning shunt subjects had cerebral rSO(2) monitoring.

Results: A total of 131 malfunctioning shunt subjects had cerebral rSO(2) monitoring. Patient's central trend and intrasubject variability of cerebral rSO(2) readings for left and right probe and malfunction sites (n = 131) are as follows: Intrasubject left and right rSO(2) Pearson correlation was -0.46 to 0.98 (mean ± SD, 0.35 ± 0.34; median, 0.34; interquartile range, 0.06-0.61). The correlation coefficients of 99 subjects between left and right rSO(2) was significantly different (P < .001), suggesting that intrasubjects' left and right rSO(2) are highly correlated. Sample mean difference between left and right rSO(2) were -1.7% (95% confidence interval [CI], -1.8 to -1.6; P < .001) supporting overall left lower than right. Intraclass correlation for left rSO(2) was 87.4% (95% CI, 87.2%-87.6%), and that for right rSO(2) was 83.8% (95% CI, 83.8%-84%), showing intersubject differences accounting for the variation, and relative to intersubject variation, intrasubjects readings are consistent. Intrasubjects, left and right rSO(2) highly correlate and are asymmetrical. Left and right rSO(2) are consistent in intrasubject with large rSO(2) variations in trend and variability across subjects.

Conclusion: This study demonstrates reliable cerebral rSO(2) readings in subjects with malfunctioning shunts, with asymmetrical cerebral rSO(2) hemispheric dynamics within subjects.

Fig. 1

Cerebral rSO₂ Near Infrared Spectroscopy sampling process.

Fig. 2

Malfunctioning Shunt Cerebral rSO₂ Time Flow (16 random subject selection (Total N = 131 study subjects): Demonstrating Subject's Unique & Asymmetrical Cerebral Dynamics: Cerebral regional tissue oxygenation (rSO₂) readings in % over time: X axis = rSO₂ values as %, Y axis = time in seconds, Left = Left cerebral rSO₂ readings, Right = Right cerebral rSO₂ readings.

Fig. 3

Pair-wise cerebral rSO₂ Differences between Left and Right rSO₂ reading for each Subject.

Fig. 4

(A) Bland-Altman Plot for cerebral rSO₂ Trend between Left and Right cerebral rSO₂ (B) Bland-Altman Plot for cerebral rSO₂ Variability between Left and Right cerebral rSO₂.

Fig. 5

Bland-Altman plot for repeated measures of cerebral rSO₂ readings from 2 subjects.