This research focuses on newborns with hypoxic ischemic encephalopathy, a brain condition that occurs when babies don’t receive enough oxygen during birth. These newborns require cooling therapy (therapeutic hypothermia) to protect their brain. The study examines how the pain medication fentanyl works in the bodies of these infants during their cooling treatment.

The study will monitor how fentanyl moves through the body when given through a vein (intravenous administration) to newborns receiving cooling therapy. The medication will be given first as a single dose, followed by continuous administration over several days. The purpose is to understand how newborns’ bodies process this pain medication while they are being treated with cooling therapy.

During the study, doctors will measure the amount of medication in the blood at different times: right after giving the first dose, and then at 24, 48, 72, and 96 hours while the medication is being given continuously. They will also watch carefully for any side effects from the medication to ensure the treatment is safe for these newborns.