Xinlong Wang1, Hanli Liu1, Srinivas Kota2, Yudhajit Das1, Yulun Liu3, Rong Zhang4, Lina Chalak5. 1. Department of Bioengineering, University of Texas at Arlington, Arlington, TX, United States. 2. Department of Neurosurgery, University of Texas Southwestern Medical Center, Dallas, TX, United States. 3. Department of Population and Data Sciences, University of Texas Southwestern Medical Center, Dallas, TX, United States. 4. Departments of Internal Medicine and Neurology, University of Texas Southwestern Medical Center, Dallas, TX, United States. 5. Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX, United States. Electronic address: Lina.chalak@utsouthwestern.edu.
Abstract
BACKGROUND: Neonatal hypoxic ischemic encephalopathy (HIE) is difficult to classify within the narrow therapeutic window of hypothermia. Neurophysiological biomarkers are needed for timely differentiation of encephalopathy severity within the short therapeutic window for initiation of hypothermia therapy. METHODS: A novel analysis of mean Phase Amplitude Coupling index, PACm, of amplitudes high frequencies (12-30 Hz) coupled with phases of low (1,2 Hz) frequencies was calculated from the 6 h EEG recorded during the first day of life. PACm values were compared to identify differences between mild versus higher-grade HIE, respectively, for each of the EEG electrodes. A receiver operating characteristic curve was generated to examine the performance of PACm. RESULTS: 38 newborns with different HIE grades were enrolled in the first 6 h of life. Threshold PACm 0.001 at Fz, O1, O2, P3, and P4 had AUC >0.9 to differentiate HIE severity and predict the persistence of moderate to severe encephalopathy that requires treatment with hypothermia. CONCLUSION: PAC is a promising biomarker to identify mild from higher severity of HIE after birth.
BACKGROUND: Neonatal hypoxic ischemic encephalopathy (HIE) is difficult to classify within the narrow therapeutic window of hypothermia. Neurophysiological biomarkers are needed for timely differentiation of encephalopathy severity within the short therapeutic window for initiation of hypothermia therapy. METHODS: A novel analysis of mean Phase Amplitude Coupling index, PACm, of amplitudes high frequencies (12-30 Hz) coupled with phases of low (1,2 Hz) frequencies was calculated from the 6 h EEG recorded during the first day of life. PACm values were compared to identify differences between mild versus higher-grade HIE, respectively, for each of the EEG electrodes. A receiver operating characteristic curve was generated to examine the performance of PACm. RESULTS: 38 newborns with different HIE grades were enrolled in the first 6 h of life. Threshold PACm 0.001 at Fz, O1, O2, P3, and P4 had AUC >0.9 to differentiate HIE severity and predict the persistence of moderate to severe encephalopathy that requires treatment with hypothermia. CONCLUSION: PAC is a promising biomarker to identify mild from higher severity of HIE after birth.