Birth asphyxia is also known as intrauterine hypoxia, or IH. It occurs when an infant does not receive enough oxygen at some point before, during, or after delivery. Without oxygen, brain cells, and other tissues will be unable to function properly. This will cause waste build-up and severe damage from the excess acids. If it is not fatal, damage from birth asphyxia may be temporary or permanent.
Causes of Birth Asphyxia
Contributing factors of birth asphyxia may include:
- Tobacco smoking during pregnancy
- Maternal hypertension or hypotension
- Maternal anemia, or lack of oxygen-carrying abilities in maternal bloodstream
- Maternal or fetal infection
- Early separation between placenta and uterus
- Insufficient relaxation of uterus, preventing adequate oxygen circulation within placenta
- Abnormally long or difficult delivery
- Umbilical cord complications
- Premature or post-term birth
- Abnormal, underdeveloped, or blocked fetal airway
- Fetal anemia, or lack of oxygen-carrying abilities in fetal bloodstream
Birth Asphyxia Symptoms
Approximately 4 out of every 1,000 full-term pregnancies experience birth asphyxia. There are two basic stages during birth asphyxia. First, the cells are damaged within minutes of inadequate oxygen supply. The second phase of birth asphyxia is referred to as “reperfusion injury.” It occurs after blood flow and oxygen have been successfully restored. The waste that built up within damaged cells during the first stage is released into the body. This phase can continue to cause harm for weeks after birth asphyxia began.
The following signs may indicate a case of birth asphyxia:
- Acidosis, or increased fetal blood acidity prior to delivery
- Abnormal fetal heartbeat prior to delivery
- Blue or pale fetal skin color during delivery
- Low heart rate immediately after delivery
- Weak cry, reflexes, or muscle tone
- Weak breathing, or complete lack of breathing
- Meconium, or first stool, is in amniotic fluid
- Circulatory, respiratory, or digestive distress
- Infant is experiencing seizures
Diagnosing Birth Asphyxia
The diagnosis of birth asphyxia involves looking for the symptoms listed above. There are different tests that may be implemented. The obstetrician suspecting birth asphyxia may test the acidity of the blood within the umbilical cord’s arteries. A pH of less than 7.00 is considered highly acidic and typically indicates birth asphyxia. An Apgar score between 0 and 3 for longer than 5 minutes after delivery is also a reliable indication of birth asphyxia.
The amount of time it takes to diagnose birth asphyxia correlates directly with the level of damage done to the infant’s brain cells and other tissue. A quicker diagnosis will allow for more effective treatment. Options for treatment may vary depending on when birth asphyxia is first suspected. Other factors for determining treatment include the severity of birth asphyxia, age, overall health, tolerance of medications, and any medical facility limitations.
Treatment options for birth asphyxia may involve:
- Supplying maternal oxygen prior to delivery
- Emergency vaginal delivery
- Emergency C-section
- Nitric oxide, administered through breathing tube
- High-frequency oscillatory ventilation, a gentler form of mechanical breathing assistance
- Extracorporeal membrane oxygenation (ECMO), providing life support for sedated infants with a heart-lung pump
- Hypothermia, cooling the infant’s temperature to 91 degrees F and preventing further brain damage during reperfusion
Certain types of respiratory therapy can harm the infant. Conventional breathing machines may require increased pressure that could damage the infant’s lungs. During ECMO, a nurse must remain by the side of the infant at all times. Hypothermia is acceptable for treating birth asphyxia only after a gestational age of 36 weeks. It is a newer procedure, and hypothermia should last no longer than 72 hours. It must be administered within 6 hours of delivery to effectively prevent brain damage. If any treatment is not administered properly, the infant may experience medical malpractice.