How do a newborn's lungs work?
The informational video below gives a helpful look at how a newborn baby's lungs work:
Transient Tachypnoea of the New-Born (TTN)
In the womb, your baby’s lungs are filled with fluid. During delivery, much of this fluid is pushed out of their lungs and absorbed into the bloodstream. If some of this fluid remains in their lungs, your baby may show symptoms of TTN - Transient Tachypnoea of the Newborn. TTN causes rapid breathing and is usually confirmed by chest x-ray. This condition is more common in term newborn babies than in preterm babies.
Treatment for TTN may involve the following:
- an oxygen rich environment, e.g., within the incubator or using nasal prongs; and/or mechanical respiratory support
- If TTN persists, your baby may be fed via a nasogastric/orogastric tube to allow them to rest.
Normally, it takes a few hours for this fluid to be absorbed out of the lungs into the bloodstream, however, it can sometimes take days. Whilst waiting to confirm the diagnosis of TTN, there may be a brief period when your baby is given intravenous antibiotics. If your baby was receiving oxygen support for TTN, it is generally slowly reduced once is has been determined that your baby is maintaining adequate oxygenation around the body.
Your baby’s lungs contain thousands of air sacs (alveoli). These air sacs allow the lungs and blood to exchange oxygen and carbon dioxide. Sometimes, the air in these sacs leaks out into the space surrounding the lungs, causing pneumothorax which prevents the lungs from fully expanding and can lead to rapid breathing (tachypnoea). The diagnosis and monitoring of the pneumothorax is generally through clinical examination and intermittent chest x-ray.
What are the treatments?
Sometimes term newborn babies develop spontaneous pneumothorax after birth with no identifiable cause. These babies are given oxygen and allowed to rest. They are also given fluids through a tube or intravenous line. In general, the pneumothorax is small and resolves over time. If the pneumothorax is large and severe, it may be necessary to perform a chest drain where a small tube is passed through the chest wall. A chest drain helps the air leave the surrounding tissue; allowing the lung tissue to expand again.
Respiratory issues are very common in term babies, and will all be treated in the NICU
Meconium Aspiration Syndrome
Meconium is a thick, black/green, odourless material that develops in the fetal intestine during the third month of pregnancy. This meconium is normally passed from the intestine within the first 24 to 48 hours after birth, colouring the baby’s stool a black/dark green colour.
The stress your baby experiences before, or during, birth may cause them to pass the meconium stool while still in the uterus. Should your baby inhale meconium-stained amniotic fluid and experience respiratory distress, it is called MAS (meconium aspiration syndrome).
Generally, MAS is not life-threatening, but can cause significant health complications for a newborn baby. Respiratory distress is the most noticeable symptom of MAS. Meconium is highly irritant, and when inhaled causes lung inflammation. Your baby may find it difficult to breathe, will breathe rapidly, and/or grunt during breathing and may need mechanical ventilation to help them breathe.
This condition can be life-threatening if complicated by respiratory failure, pulmonary air leaks, and persistent pulmonary hypertension. Some newborn babies may stop breathing if their airways are completely blocked by meconium. These babies may also exhibit the following symptoms:
- a slightly blue skin colour, which is called cyanosis
- low blood pressure
What are the treatments?
If MAS occurs, your newborn baby will need immediate treatment to remove the meconium from their upper airways. After delivery, the doctor will immediately suction the nose, mouth, and throat. A tube may be placed into your baby’s windpipe (or trachea) to suction the meconium from their windpipe. The suctioning will continue until no meconium is seen in the material removed.
If your newborn baby is not breathing or has a low heart rate, your doctor will use a bag and mask to help them breathe. This will deliver oxygen to your baby and help inflate their lungs. After emergency treatment has been provided, your baby will require antibiotics, as meconium in the lungs can cause infection. They will be nursed in an incubator because they will need continuous monitoring and/or an increased oxygen supply. The tube may be left in your baby’s windpipe to help them breathe if they are very ill or not breathing on their own.
Pneumonia is the condition where the lungs are inflamed. It is usually caused by an infection from group B streptococcal bacteria but it can also be caused by a virus.
If the onset of pneumonia occurs within hours of birth, your baby may have acquired it before, or during, birth, and it is likely to be part of a generalised sepsis syndrome. If the onset of pneumonia is after 7 days, the infection is likely confined to the lungs.
The risk of a baby developing pneumonia is increased in cases where the mother has:
- an unexpected high temperature in labour
- prolonged rupture of membranes
- a meconium-stained or foul smelling liquor/amniotic fluid
- a history of recurrent genitourinary infection in pregnancy.
In the neonatal unit, it commonly occurs amongst babies who require or have had prolonged endotracheal intubation because of lung disease.
In spite of radiological imaging, pneumonia can be difficult to diagnose in newborn babies because it can be difficult to obtain secretions from them. Signs of pneumomia may be limited to respiratory distress, but may also include the following:
- a high temperature, typically over 102 °F
- lack of energy
- laboured breathing
- Breathing patterns may be either rapid, but shallow, or from the stomach instead of the chest. These breathing patterns may also be along with excessive nose flaring or wheezing.
There is also the possibility that your baby will need some help breathing through mechanical ventilation. Your baby may be unable, or too breathless, to feed from the breast or bottle; and might require some tube feeds until they are well again.
Diagnosis is made by x-ray, as well as a clinical and laboratory evaluation (observation and blood tests), if testing for a generalised sepsis syndrome.
What are the treatments?
Treatment is initially with broad-spectrum antibiotics which are changed to organism-specific antibiotics as soon as possible following laboratory results/culture reports. To fight the infection, antibiotics are given through an intravenous line or cannula.
Extracorporeal Membrane Oxygen (ECMO)
Note: This technique is not carried out in the neonatal unit of Cork University Maternity Hospital. If your baby needs this treatment, they will be transferred to another hospital.
A technique called ECO (Extracorporeal Membrane Oxygen) may be required to ensure your baby receives an adequate delivery of oxygen to their tissues. ECMO involves an artificial lung outside your baby’s body. Your baby’s blood is oxygenated by moving their blood through this artificial lung and then sending it back into their body. This technique is generally used in patients suffering from cardiac and/or respiratory failure and it is widely used in babies.
In cases of respiratory failure, this modified heart-lung machine takes over part of, if not all, the work of the heart and lungs. This gives the baby’s lungs time to rest and recover while the tissues continue to be supplied with oxygen.