by EBSCO Medical Review Board
(Hypoxic Ischemic Encephalopathy; HIE; Cerebral Hypoxia)

Definition

Perinatal asphyxia is a condition in which a baby’s brain does not receive enough oxygen before, during, or after birth. This results in cardiorespiratory or brain damage.

Asphyxia can be fatal. Brain cells can begin dying within as little as 5 minutes without oxygen. It can also cause permanent, long-term damage, including intellectual disability , delayed development, seizure disorder , and cerebral palsy.

Causes

Perinatal asphyxia can be caused by a number of conditions that stop or slow the normal blood and oxygen flow to the baby's brain before or during labor and delivery. Some factors that may cause these problems include:

  • Drop in the mother's blood pressure, which can decrease flow to the baby
  • Pressure on the umbilical cord—interrupts flow of oxygen-rich blood to the baby
  • Problems with the placenta, such as placental abruption when placenta moves away from the wall of the uterus

Risk Factors

Factors that may increase your baby’s chance of perinatal asphyxia include:

  • Fetal heart rate abnormalities
  • Water breaking more than 12 hours before delivery
  • Meconium (infant bowel contents) in the fluid surrounding the baby before birth
  • Hemorrhage occurring prior to childbirth
  • Infection in the mother that may cause breathing problems, such as pneumonia
  • Prolonged first and second stages of labor
  • Pre- or post-term labor
  • Delivery with forceps or a vacuum device

Symptoms

Mild asphyxia may cause:

  • Poor muscle tone
  • Irritability
  • Extreme drowsiness
  • Feeding difficulties, including poor suck

Severe asphyxia may cause:

  • Seizures
  • Poor arousal
  • Blue-colored skin or lips
  • Difficulty breathing

Diagnosis

A physical exam will be done. Typically, the history is the most important factor in making the diagnosis.

Your baby’s body fluids may be tested. This can be done with blood tests, urine tests, stool tests, and tests of the fluid around the brain and spine.

Images may need to be taken of your baby’s body structures. This can be done with:

Your baby’s heart and brain activity may also be tested. This can be done with:

Treatment

Life-sustaining Treatment

Life-sustaining treatment may be used if reduced brain function has happened, but there is no extensive damage yet. Treatment options include mechanical ventilation to take over or support breathing and oxygen therapy. These treatments will be stopped as your baby recovers.

Medications

Medication may be needed to support heart function until your baby recovers. Medication and general anesthesia may also be given to control seizures.

Lowering Body Temperature

Your baby may be wrapped in cooling blankets within hours of birth. This will lower body temperature and reduce the risk of tissue injury and reduce the risk of long-term problems.

Prevention

In most cases, asphyxia is sudden and cannot be prevented.

RESOURCES

Brain Injury Association of America  http://www.biausa.org 

National Institute of Neurological Disorders and Stroke  http://www.ninds.nih.gov 

CANADIAN RESOURCES

Health Canada  https://www.canada.ca 

Ontario Brain Injury Association  http://www.obia.ca 

References

Birth asphyxia. Seattle Children's website. Available at: http://www.seattlechildrens.org/medical-conditions/airway/birth-asphyxia. Accessed January 29, 2021.

Edwards AD. The discovery of hypothermic neural rescue therapy for perinatal hypoxic-ischemic encephalopathy. Semin Pediatr Neurol. 2009;16(4):200-206.

Harrington DJ, Redman CW, Moulden M, Greenwood CE. The long-term outcome in surviving infants with Apgar zero at 10 minutes: a systematic review of the literature and hospital-based cohort. Am J Obstet Gynecol . 2007;196(5):463.e1-e5.

Itoo BA, Al-Hawsawi ZM, et al. Hypoxic ischemic encephalopathy. Incidence and risk factors in North Western Saudi Arabia. Saudi Med J. 2003;24(2):147-153.

Lai MC, Yang SN. Perinatal hypoxic-ischemic encephalopathy. J Biomed Biotechnol. [Epub 2010 Dec 13].

Neonatal hypoxic-ischemic encephalopathy (HIE). EBSCO DynaMed Plus website. Available at:  http://www.dynamed.com/topics/dmp~AN~T116449/Neonatal-hypoxic-ischemic-encephalopathy-HIE  . Accessed January 29, 2021.

8/11/2014 DynaMed Plus Systematic Literature Surveillance  http://www.dynamed.com/topics/dmp~AN~T116449/Neonatal-hypoxic-ischemic-encephalopathy-HIE  : Azzopardi D, Strohm B, Marlow N, et al. Effects of hypothermia for perinatal asphyxia on childhood outcomes. N Engl J Med. 2014;371(2):140-149.

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