Asphyxia Neonatorum - Causes, Clinical Manifestations, Diagnosis, and Treatment

What Is Asphyxia Neonatorum?

Asphyxia neonatorum is also known as perinatal asphyxia or birth asphyxia. It is a condition where the baby does not get sufficient oxygen during birth, before, or immediately after birth. It is life-threatening and can result in serious complications.

What Are the Causes of Asphyxia Neonatorum?

Asphyxia neonatorum can be caused by any factor that affects the baby's capacity to take in oxygen. Hence, monitoring and managing the mother and baby's oxygen levels at delivery is essential. Lower oxygen level decreases the infant's heart rate and blood pressure. It also reduces the amount of blood flowing out of the heart. Less blood flow can result in organ and tissue damage. It also results in acidosis (excess acid) in the baby's blood.

• Reasons for Decreased Blood Supply During or Before Birth Include:

  • Low oxygen level in the mother's blood. It can be due to heart or respiratory issues or due to the effect of anesthesia.

  • Insufficient uterus relaxation during labor decreases the oxygen supply to the placenta.

  • Early placental separation from the uterus decreases the amount of oxygen that reaches the fetus.

  • Umbilical cord compression results in decreased blood flow and hence less oxygen to the fetus.

  • Any infection or allergy reaction.

  • Difficult labor.

  • High or low blood pressure in the mother.

• Reasons for Decreased Blood Supply After Birth Include:

  • Anemia reduces the oxygen-carrying capacity of the blood.

  • Any heart or lung disease.

  • Pre-term birth of the baby.

  • Airway obstruction in the baby limits oxygen supply.

What Is the Pathophysiology of Asphyxia Neonatorum?

Brain injury resulting from decreased oxygen and blood supply to the brain has three stages. During the first stage, neuron injury occurs due to a reduced supply of oxygen and glucose to the brain. As a result, the sodium-potassium pump fails, resulting in cell swelling and cell death. After the immediate injury, there is a latency period of six hours where the cells try to recover from the damage. During this stage, the blood flows to and from the damaged areas, spreading toxic neurotransmitters and causing secondary neuronal injury.

What Are the Risk Factors for Asphyxia Neonatorum?

The various risk factors for asphyxia neonatorum are mentioned below.

• Maternal age less than 20 years or more than 40 years.

• Delivering multiple babies simultaneously, as in cases of twins and triplets.

• No proper prenatal care.

• Low birth weight of the baby.

• Abnormal fetal position.

• Mother's illnesses like high blood pressure, diabetes, etc.

• Medical history of birth asphyxia in previous deliveries.

• Alcohol abuse or smoking during the pregnancy period.

What Are the Signs and Symptoms of Asphyxia Neonatorum?

The signs and symptoms of asphyxia neonatorum vary for each baby. The symptoms can appear before, during, or after the baby's birth.

• Symptoms Before Delivery Include:

  • The elevated acid level in the baby's blood indicates acidosis.

  • Abnormal heart rate.

• Symptoms After Delivery Include:

  • Decreased heart rate.

  • Skin color appears blue.

  • Muscles become weak.

  • Weak reflexes.

  • Difficulty in breathing or soft breathing.

  • Soft or no crying sound.

  • Lethargic baby.

  • Amniotic fluid is stained with meconium.

  • The baby does not urinate.

  • Blood clots are seen in a few cases.

The symptoms become severe and might damage the baby's kidneys, brain, heart, and lungs if devoid of proper oxygen supply for a longer time.

What Is the Diagnosis of Asphyxia Neonatorum?

Diagnosis for asphyxia neonatorum is made in the following manner.

• If acidosis or increased acid level is detected in the fetal blood (pH less than 7), asphyxia neonatorum is suspected.

• Any problem with the newborn's circulatory, digestive, and respiratory systems indicates birth asphyxia.

• If any neurological problem like seizures, coma, or weak muscles is detected, the newborn should be checked for asphyxia neonatorum.

• Respiratory problems and decreased blood flow to the kidneys and heart is indicative of asphyxia neonatorum.

• Apgar score is the score given to newborns after examining their heart rate, muscle tone, skin, and reflexes. The Apgar score of 0 to 3 for longer than 5 minutes indicates asphyxia in newborns. A score of 7 to 10 is for healthy babies, and a score between 4 to 7 indicates mild depression of the vital signs.

  • A- Appearance (skin color).

  • P- Pulse (heart rate).

  • G- Grimace response (reflexes).

  • A- Activity (muscle tone).

  • R- Respiration (breathing rate).

What Is the Differential Diagnosis of Asphyxia Neonatorum?

The differential diagnosis for asphyxia neonatorum includes:

• Brain tumors.

• Infections.

• Developmental defects.

• Methylmalonic acidemia.

• Neurological disorders.

What Is the Treatment of Asphyxia Neonatorum?

Asphyxia neonatorum is a life-threatening condition and is difficult to predict. Immediate intervention by a team of doctors is needed to minimize the damaging effects that are caused due to decreased oxygen supply to the baby. The treatment plan for asphyxia neonatorum is based on the cause and severity of the symptoms in the baby.

• Immediate Treatment for Asphyxia Neonatorum Includes the Following:

  • Extra oxygen support to the mother if asphyxia neonatorum is diagnosed before the delivery.

  • Emergency surgery (C-section) is planned.

  • Use of a respirator - The baby is placed immediately on the respirator after birth.

  • Clearing the airway passage by suctioning away the fluids in case of meconium aspiration syndrome (MAS).

• Severe Birth Asphyxia Needs the Below-Mentioned Measures:

  • Hyperbaric oxygen tank.

  • Medication to control blood pressure and seizures.

  • Regular monitoring of blood pressure and fluid intake.

  • ECMO (extracorporeal membrane oxygenator) - It is a machine similar to a heart-lung bypass machine. ECMO helps maintain the baby's heart and lung functions with the help of an oxygenator and external pump.

How Can Asphyxia Neonatorum Be Prevented?

Fetuses with a high chance of developing asphyxia neonatorum should be identified, and healthcare providers should schedule regular checkups to monitor the heart rate. Doctors should carefully monitor high-risk pregnancies. The mother should be encouraged to give birth in hospitals equipped with neonatal intensive care units so newborns can be treated for asphyxia neonatorum. The medical team must be ready to carry out appropriate measures during the labor process and be prepared for resuscitation.

Conclusion

Reduced oxygen supply to the organs and tissues causes immediate damage within minutes. Babies with mild to moderate asphyxia recover completely upon receiving proper care and timely treatment. Severe cases of asphyxia neonatorum can result in a fatality, with most deaths within the first few days after birth. Infants who survive severe asphyxia neonatorum show signs of mild to moderate neurological defects. The majority of the deaths occur from aspiration and systemic infections. Long-term complications include cerebral palsy and developmental delays in newborns. Proper monitoring of both mother and infant is necessary before and after birth to avoid the risks of asphyxia neonatorum.