Globally, an estimated 1.8 to 7.7 infants per 1000 live term births suffer from perinatal asphyxia, which remains an important cause of neonatal encephalopathy (NE) and neurodevelopmental impairment. Over the last six years, several randomized control trials have demonstrated that prolonged and moderate therapeutic hypothermia (TH) reduces the rate of death or disability at 18 months of age among infants who survived. In these trials, infants were eligible if there was evidence of perinatal hypoxia-ischemia and a moderate or severe degree of encephalopathy on neurological evaluation performed at ≤ 6 hrs of age. However, it has been recognized that the level of NE may change over time. Preliminary and unpublished observations from our group indicated that some infants who were not classified as moderate or severe NE had neurological abnormalities at discharge or evidence of brain injury on MRI performed during the neonatal period. Unfortunately, precise data on the outcomes of this specific population is not clear. Since TH is not offered to this population, the outcomes of infants that do not qualify for TH based on neurological evaluation performed ≤ 6 hrs of life requires a more precise investigation.
