Transfontanellar duplex brain ultrasonography resistive indices as a prognostic tool in neonatal hypoxic-ischemic encephalopathy before and after treatment with therapeutic hypothermia

Abstract

OBJECTIVEPrior to therapeutic hypothermia (i.e., cooling), transfontanellar duplex brain sonography resistive indices (RI) were studied as bedside non-invasive measures of cerebral hemodynamics in neonates who suffered from hypoxic-ischemic encephalopathy (HIE). We compared pre- and post-cooling RI values and examined the relationships between RI values and specific long-term neurodevelopmental outcomes.STUDY DESIGNTransfontanellar duplex brain sonography, including RI, were obtained for 28 neonates prior to brain cooling and for 20 neonates following brain cooling. All RI values were sampled in the anterior cerebral artery at the beginning of each ultrasound study. Neurodevelopmental assessment was conducted between ages 20-32 months with the Mullen Scale of Early Learning. The relationships between pre- and post-cooling RI and cognitive and motor outcomes were studied.RESULTNeonates with RI values <0.60 prior to and following cooling were more likely to die or have severe neurodevelopmental disability by ages 20-32 months than those with RI >0.60. Lower RI values were associated with specific neurodevelopmental deficits in motor skill attainment.CONCLUSIONPre- and post-cooling transfontanellar duplex brain sonography RI values may be a useful prognostic tool, in conjunction with other clinical information, for neonates diagnosed with HIE. The results of this study suggest that further study of the prognostic value of RI values for short- and long-term outcomes is warranted.

Head Ultrasound in Neonatal Hypoxic-Ischemic Injury and Its Mimickers for Clinicians: A Review of the Patterns of Injury and the Evolution of Findings Over Time

“…This may be due to the confounding effect of increased intracranial pressure, patent ductus arteriosus, or cardiac dysfunction. If an RI is performed early enough after admission and before or simultaneous with the onset of TH, a low RI value may retain some of its prognostic value [30]. Its predictive value returns once the infant is rewarmed [31].…”

Evaluating a Targeted Bedside Measure of Cerebral Perfusion in a Nonhuman Primate Model of Neonatal Hypoxic‐Ischemic Encephalopathy

“…This finding may be related to differences in the RI between humans and nonhuman primates, as we were unable to find studies in the literature that documented normal RI values in nonhuman primates for comparison. A recent study of 28 infants demonstrated that an RI value of less than 0.6 before and after cooling was associated with death or severe neurodevelopmental disability, and essentially all of our measures, even in the control neonates, had an RI of less than 0.6. This study would need to be repeated in human neonates to evaluate whether the difference in the RI indicated a difference in species or the imaging technique.…”

The Johns Hopkins Neurosciences Intensive Care Nursery Tenth Anniversary (2009-2019): A Historical Reflection and Vision for the Future

“…This information aids in the long-term prediction of outcomes and family counseling. 11,15,[33][34][35][36][37][38] Well-established interdepartmental protocols and direct communication between neonatal intensive care unit nursing and pediatric radiology technologists greatly influence successful acquisition of diagnostic examinations.…”