The signs and symptoms of HIE can be divided into three groups:
- HIE signs appearing during the fetal period
- HIE signs appearing in the neonatal period (shortly after birth)
- HIE signs that appear later in infancy
It is essential that physicians recognize the signs and symptoms of HIE occurring before or shortly after birth. This is because hypothermia therapy (the only known treatment that can prevent or minimize the damages associated with HIE at the present time) must be administered shortly after the hypoxic-ischemic event in order to prevent or reduce brain damage.
Signs and Symptoms of HIE Before 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 in the form of an emergency C-section, or intrauterine resuscitation in order to prevent further damage. With any of the following, doctors should take prompt note and begin an assessment to decide whether HIE is occurring:
- Decreased fetal movement
- Severe maternal cramping (often accompanied by severe back pain)
- Abnormal fetal heart rate
- Vaginal bleeding
- Abnormal maternal weight gain (outside of the range of 20-40 pounds)
- Maternal high blood pressure
It is important to note that when these signs occur in the mother, it is in many cases not too late to prevent HIE in the baby. 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 and decide how to proceed safely.
Signs and Symptoms of HIE at Birth or Right After Delivery
When HIE occurs, one or more of the following indicators may be present at or shortly after birth:
- Low Apgar scores for longer than 5 minutes
- Difficulty feeding
- Resuscitation required at birth, or presence of severe breathing problems
- Metabolic or mixed acidemia (low pH in umbilical cord blood gas tests)
- Organ problems (failure, damage)
- Abnormal response to light
- State of abnormal consciousness (hyperalert or lethargic)
- Presence of coma
- Weak or absent cry
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.
Signs and Symptoms of HIE During Infancy
In some children with HIE, especially those with mild to moderate HIE, 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 in their infant, 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.
- Wu, Yvonne, et al. Clinical features, diagnosis, and treatment of neonatal encephalopathy. UptoDate. Accessed 30 Jan. 2017.
- Kurinczuk, Jennifer J. Epidemiology of neonatal encephalopathy and hypoxic–ischaemic encephalopathy, Early Human Development, Volume 86, Issue 6, June 2010, Pages 329-338, ISSN 0378-3782, https://www.ncbi.nlm.nih.gov/pubmed/20554402.