Hypoxic-ischemic encephalopathy (HIE) is a type of newborn brain damage caused by oxygen deprivation and limited blood flow. HIE is a type of birth injury; this is a broad term used to refer to any harm that a baby experiences at or near the time of birth. Other terms used for HIE include birth asphyxia, perinatal asphyxia, and neonatal encephalopathy.