Clinical Usefulness of Regional Tissue Oxygen Saturation Monitoring Using Near-Infrared Spectroscopy in Neonates

Abstract

Objective Recently, near-infrared spectroscopy (NIRS) has been introduced in the neonatal intensive care unit (NICU) to monitor the altered hemodynamic status causing cerebral hypoxemia or affecting mesenteric and/or renal oxygenation. This study aimed to reassess the clinical usefulness of NIRS and the correlation between regional O2 saturation (rSO2) and various physiological parameters in neonates.

Methods Thirty-nine newborns, admitted in NICU from June 2019 to June 2020 and continuously monitored with NIRS (cerebral and renal) during the first 72 hours, were included.

Results Among 39 newborns with a median gestational age of 33.9 weeks, and a median birth weight of 2,180 g, the median of the cerebral and renal rSO2 were 84% (30%–95%) and 95% (45%–95%), respectively. Cerebral rSO2 tended to increase over time since the time of delivery, while renal rSO2 tended to decline, especially in preterm infants. Average of renal rSO2 during 72 hours showed a statistically significant difference between term and preterm infants (P<0.05). Cerebral rSO2 showed significant correlation with hemoglobin (r=0.35, P<0.05) and hematocrit (r=0.37, P<0.05). Renal rSO2 showed significant correlation with capillary blood gas analysis such as pH (r=0.36, P<0.05), pCO2 (r=-0.19, P<0.05), pO2 (r=0.23, P<0.05), base excess (r=0.19, P<0.05), hemoglobin (r=0.33, P<0.05), hematocrit (r=0.32, P<0.05) as well as renal function indicator such as blood urea nitrogen (r=-0.50, P<0.05) and creatinine (r=-0.59, P<0.05).

Conclusion We re-evaluated the clinical usefulness of NIRS in neonates by identifying trends and correlations of rSO2 with clinical parameters. It is necessary to confirm its effectiveness through further study.