The signs and symptoms of hypoxic-ischemic encephalopathy (HIE) can be divided into three groups:
HIE signs that appear before or during birth
HIE signs in the neonatal period (shortly after birth)
HIE signs that appear later in infancy or childhood
It is essential that physicians recognize the signs and symptoms of HIE occurring before or shortly after birth.
This is because therapeutic hypothermia, the only established treatment that can prevent or minimize permanent
brain damage from HIE, must be administered shortly after the oxygen deprivation occurs.
Current guidelines dictate that this therapy be given within six hours of the hypoxic-ischemic (oxygen-depriving) event.
In many cases, this means within six hours of birth
HIE signs that appear before or during birth
When an oxygen-depriving event occurs before delivery,
a baby may exhibit noticeable signs of distress from within the womb.
These signs may indicate that a pregnancy requires immediate intervention such as
intrauterine resuscitation or an emergency C-section.
With any of the following, doctors should take prompt note and begin an assessment
to decide whether a baby is at risk of HIE:
Decreased fetal movement
Severe maternal cramping (often accompanied by severe back pain)
Abnormal fetal heart rate
Abnormal contraction pattern
Vaginal bleeding
Abnormally low or high maternal weight gain
Maternal high blood pressure
It is important to note that when these signs occur, it may still be possible to prevent HIE.
Doctors should instruct mothers how to recognize these signs of fetal distress, and
they should monitor high-risk pregnancies closely in case an oxygen-depriving event occurs.
When physicians recognize any of the above signs, they should immediately begin to assess the
baby’s health and decide how to proceed safely. Failure to provide proper prenatal
testing or respond to signs of distress is negligence.
HIE signs in the neonatal period
When HIE occurs, one or more of the following indicators may be present shortly after birth (1, 2):
Low Apgar scores at five or 10 minutes
Seizures
Difficulty feeding
Breathing problems
Hypotonia (low muscle tone)
Organ problems (failure, damage)
Acidemia (low pH in umbilical cord blood gas tests)
Abnormal response to light
State of abnormal consciousness (hyperalert or lethargic)
Coma
When these signs and symptoms are present around the time of birth, it is crucial that medical
professionals take note of them, and respond promptly. A rapid clinical assessment of any
newborn presenting with signs of HIE is necessary in order to determine if therapeutic
hypothermia should be administered.
HIE signs that appear later in infancy or childhood
In some children with HIE, especially those with mild to moderate HIE,
obvious signs and symptoms of an oxygen-depriving event may not be present
at the time of birth. In these cases, HIE may become evident later in infancy
when one or more of the following occur:
Impaired motor function
Delayed developmental milestones
Seizure disorder
Delayed growth
Hearing and visual impairments
When parents notice these signs and symptoms, it is important for them to contact a healthcare professional. At this point, if doctors diagnose HIE, the child can receive assistance and care quickly to maximize their abilities.
It is important to note that although signs may not emerge in the neonatal period, medical professionals should still conduct tests – such as brain imaging or electroencephalogram (EEG) – on newborns who experienced oxygen-depriving events. These
tests may reveal brain injuries that routine neonatal tests would not. If a doctor fails to properly assess a baby at risk of HIE, and therefore misses the window to provide therapeutic hypothermia, this is medical malpractice. In some cases, doctors or nurses may neglect to conduct
proper testing because they are attempting to cover up a mistake that caused therapeutic hypothermia in the first place. This is unacceptable; medical professionals should always own up to their mistakes and do everything they can to prevent permanent damage.