Some babies need just a little help with oxygenation, so they receive O2 through prongs in their nose called a nasal cannula.  High flow oxygen through a nasal cannula is currently being studied.

Other babies need more help, so a machine is used to force a small amount of continuous pressure into the baby’s airway, which keeps the lungs open and helps with breathing and oxygenation.  This continuous positive airway pressure (CPAP) can help prevent periods of apnea, which is when the baby has periods whereby she stops breathing for 20 seconds or more.  CPAP can be given through nasal prongs or a mask.  BiPAP is a variation of CPAP, giving the baby a little more help with breathing in addition to a continuous airway pressure.

If a baby needs more help than CPAP or BiPAP can offer, but the physician does not want to put a tube (Et tube) in the baby’s upper airway (intubation) to help her breathe, nasal intermittent positive pressure ventilation (NIPPV) can be used.  NIPPV is what physicians typically use on the baby before using an invasive form of ventilation that requires intubation.  NIPPV is CPAP with positive pressure breaths given to the baby at set intervals.  A positive pressure breath is air forced into the baby’s lungs.  Even though CPAP is a treatment for apnea, a baby can still have apneic periods while on CPAP or BiPAP.  NIPPV, however, allows the medical team to set a number of breaths that a baby will get per minute to make sure a baseline level of ventilation is met.

The next step is intubation.  Since this is invasive, it poses additional risks to the baby, and physicians typically try other methods of ventilatory assistance before intubating a baby.  Of course, in an emergent situation such as in the case of severe respiratory distress, time should not be wasted on use of other methods.  Intubation establishes an airway in the baby and allows for precise volumes or pressures of air to be delivered to the baby.  Many components of oxygenation and ventilation can be controlled when a baby is intubated, such as the baby’s breathing rate and inspired oxygen level.  Intubation also allows certain drugs to be easily delivered, such as surfactant, which is given to help a premature baby’s lungs mature and become more compliant.

With nasal prongs or a mask, the medical team has to worry about air leaking out; the more air that leaks, the less help the baby will be getting.  The goal of NIPPV is to give the baby ventilatory help that is similar to what the baby can receive if intubated.  Sometimes, however, air leaks prevent this from happening.  Air leaks that occur with non-invasive forms of breathing assistance do not occur with intubation.

NIPPV is often used for apnea of prematurity (apneic periods that occur due to the baby’s immature systems), after a baby is extubated (breathing tube taken out), and when a premature baby has respiratory distress.

Invasive ventilation (intubation) with positive pressure (IPPV) is indicated when ONE of the following conditions is present:

1. The baby’s blood is acidic.  This means the pH is abnormally low (< 7.2) and the CO2 in the blood is abnormally high (PaCO2 > 60-65).
2. The baby has a low level of oxygen in her blood (PaO2 < 50), despite being given supplement O2, OR the baby is requiring a lot of oxygen while on CPAP.
3. The baby has severe apnea.

IPPV is commonly used for the following:

• Respiratory distress syndrome (RDS)
• Apnea
• Infection such as sepsis and/or pneumonia
• Persistent pulmonary hypertension
• Congenital heart and lung problems
• Meconium aspiration syndrome

IPPV increases the chances that a baby will have ventilator associated pneumonia and bronchopulmonary dysplasia (BPD).  BPD is inflammation and scarring of the lungs, and it is associated with long-term ventilator use.  If the medical team follows standards of care, including keeping the peak pressure in the baby’s lungs low, the risk of BPD and pneumonia decreases.

All babies should have their oxygen saturation and work of breathing closely monitored, and if a baby is experiencing low oxygen levels, respiratory distress or apneic events, blood gases need to be regularly drawn in order to assess the baby’s O2, CO2 and pH levels.  This is especially important if a baby is on a ventilator.  Overventilation injuries can occur if ventilation is not properly managed.  First of all, if pressures in the baby’s lungs are too high, the baby could develop bronchopulmonary dysplasia (BPD), although this typically doesn’t occur unless the baby is on the vent for more than 28 days.

Secondly, a pneumothorax or pneumothoraces may occur if the volumes of air administered during ventilation are too large and create too much pressure in the baby’s lungs.  When pressures in the baby’s lungs are too high, the alveoli (tiny air sacs in the lungs where gas exchange takes place) become over-distended and rupture.  This results in holes in the lungs which allow air to leak through into the spaces around the lungs, forming a pneumothorax.  This build-up of air prevents the lung from fully expanding. The longer this is left untreated, the more air there is that leaks into the space around the lungs, which further restricts the ability of the lung to expand.  This can cause pressure in the lungs to increase even more, and it also hinders gas exchange, which can cause hypoxia and acidosis.

The pneumothorax may also compress the veins that bring blood to the heart.  As a result, less blood fills the chambers of the heart, the output of the heart decreases, and the baby’s blood pressure drops. This also can lead to serious problems and can cause a lack of blood flow to the brain, thereby further increasing the chances of brain damage.

Thirdly, the ventilator may be working so well that the baby gets rid of too much CO2 (hypocarbia).  Abnormally low CO2 levels are often overlooked in the hospital, but even 5 or 6 hours of a low CO2 level can cause permanent brain damage such as periventricular leukomalacai (PVL) and cerebral palsy.  It is very important for the medical team to pay close attention to a baby’s CO2 levels.  Certain factors, such as surfactant administration, can cause a baby’s lungs to become more compliant, which usually means she will be getting rid of more CO2 while on the ventilator.  A wide variety of factors can affect a baby’s CO2 levels, and it is important for changes to be made to the ventilator very quickly if the baby’s CO2 level becomes low.  Hypocarbia is very easy to correct by simple changes in the vent settings, and there is absolutely no excuse for prolonged hypocarbia.

One area of breathing mismanagement commonly seen is failure to properly treat respiratory distress, apnea, hypoxia and acidosis (high CO2 levels causing a low pH).  Apneic events, chronic hypoxia and acidosis can cause permanent brain damage, such as hypoxic ischemic encephalopathy (HIE), periventricular leukomalacia (PVL) and cerebral palsy.  Respiratory distress can cause chronic hypoxia and acidosis, and it is also associated with apnea.  Sometimes the medical team wants to avoid intubation due to the risks intubation poses, and the baby is kept on less invasive methods of breathing and oxygenation management.  With proper management, though, the risks of IPPV can be significantly reduced.  The consequence of not treating apnea, hypoxia and acidosis is potential permanent brain damage.

Indeed, we have seen cases in which a baby has numerous documented episodes in which she stops breathing, her heart beat becomes really slow, the oxygen level in her blood plummets, and she turns dusky or blue and has to be stimulated to breathe again, with many of the apneic events lasting for one or more minutes.  This apnea can last for a week or much longer.  Sometimes the physicians think that a baby will outgrow the apnea, and indeed that usually happens.  But that is no excuse for letting a baby suffer periods of oxygen deprivation and a very slow heart rate (bradycardia), which can cause permanent brain damage such as hypoxic ischemic encephalopathy (HIE) and cerebral palsy.

Respiratory distress and apnea both frequently occur in premature babies.  Respiratory distress syndrome (RDS) occurs when a baby’s lungs aren’t fully developed and are non-compliant (lack elasticity).  RDS can cause a baby to struggle to breathe, and often, the baby has a hard time getting enough oxygen and getting rid of enough carbon dioxide.  This leads to hypoxia and acidosis, both of which can cause permanent brain injury, such as cerebral palsy.  (If the baby has chronically high CO2 levels, the kidneys might compensate by helping the body create more of a buffer, thereby making the pH level go back to normal and not be acidic.)  If non-invasive modes of ventilation aren’t working to help prevent hypoxia, acidosis and / or increased work of breathing, the baby must be intubated / placed on IPPV.

O2 through a nasal cannula can sometimes help with apnea, but it is not considered a standard treatment.  CPAP and BiPAP are treatments for apnea, and if these treatments aren’t preventing severe apnea (which they usually do), the baby should be intubated.  Often, the physician will try NIPPV first, and if that isn’t properly managing the apnea – which often occurs along with RDS – the baby will then be intubated.  IPPV can completely eliminate apneic episodes and decrease the baby’s work of breathing.  IPPV also allows for a much more precise control of oxygenation and CO2 elimination, and when a baby has a breathing tube, she is easier to suction, which is very important when a baby has meconium aspiration syndrome, which can cause the baby to have a lot of secretions as well as respiratory distress.  Aseptic and sterile techniques should be used to prevent ventilator associated pneumonia, and the pressures in the lungs should be kept low to prevent BPD.

If a baby has abnormally high lung pressures, she should be placed on a ventilator that gives small and very frequent breaths, called high frequency ventilation or oscillation.  With current in-line suction catheters and other devices that help keep procedures aseptic or sterile, and with the development of high-frequency ventilators, pneumonia and BPD aren’t the problem they once were with ventilators.  The bottom line is that there is no excuse for failing to intubate a baby when she is having severe apnea, respiratory distress and / or acidosis that cannot be managed with non-invasive methods.

As mentioned earlier, apnea can frequently be easily managed with CPAP or BiPAP, as well as with caffeine.  But apnea in premature infants is often accompanied by respiratory distress, which often means that intubation is necessary.

Too much oxygen can not only cause retinopathy of prematurity (ROP), but it can also cause lung damage, including bronchopulmonary dysplasia (BPD).  Indeed, very close monitoring of a baby’s O2, CO2 and pH must occur, especially if the baby is premature and / or getting help with her breathing.  Failure to keep a baby’s O2, CO2 and pH levels normal can cause conditions such as retinopathy of prematurity (ROP), hypoxic ischemic encephalopathy (HIE), cerebral palsy and periventricular leukomalacia (PVL).