Association between cerebral oxygen saturation and brain injury in neonates receiving therapeutic hypothermia for neonatal encephalopathy

Abstract
Objective To assess the association of cerebral oxygen saturation (CrSO2) collected by near infrared spectroscopy (NIRS) during therapeutic hypothermia (TH) and rewarming with evidence of brain injury on post-rewarming MRI. Study design This retrospective cohort study included 49 infants, who received TH for mild to severe neonatal encephalopathy. Of those, 26 presented with brain injury assessed by a novel MRI grading system, whereas 23 had normal MRI scans. Results CrSO2 increased significantly from the first to the second day of TH in infants with brain injury, whereas it remained stable in patients with normal MRI. Increasing mean CrSO2 values during rewarming was associated with brain injury (aOR 1.14; 95% CI 1.00–1.28), specifically with gray matter (GM) injury (aOR 1.23; 95% CI 1.02–1.49). The area under the ROC curve showed an excellent discrimination for GM involvement. Conclusion Clinically applied NIRS during TH and rewarming can assist in identifying the risk for brain injury.