Preemies and Breathing Difficulties

Premature babies may need help from a ventilator if their immature lungs are too stiff to work properly (this is called Respiratory Distress Syndrome or RDS) and/or their brain is not yet ready to control their breathing to keep it regular (recurrent apnoea). Given time, these conditions improve naturally, provided the baby is kept healthy on a ventilator. Most babies can be taken off the ventilator and off oxygen as soon as these problems have resolved themselves.

Babies born under 30 weeks and 3lbs normally require mechanical ventilation. Those born under 26 weeks or 2lbs usually require a high frequency oscillator - this pumps upto 300 breaths per minute. Babies born between 30 - 33 weeks will usually avoid mechanical ventilation, but they will require a machine called CPAP. CPAP does not breathe for them, it simply applies a constant pressure to keep the lungs open, thus making it easier for them to breathe. Babies born between 33-36 weeks may require short term use of a nasal canual. This keeps their oxygen levels stable until their lungs and brain mature. Premature babies have not yet developed an immune system, this leaves them vulnerable to infection. Such infections can stop the lungs from functioning efficiently, this is another main cause for long term ventilation as it takes a long time for the baby to overcome the illness and recover. Unfortunately, it is often the ventilator itself that leads to baby developing infection and inflammation on their lungs (as ventilators are like breeding grounds for bacteria!). Babies are classed as having Chronic Lung Disease once they have required ventilation for over 28 days, or past 34 weeks of gestational age.

Chronic Lung Disease is a condition which can occur where babies have needed long term support from a ventilator, therefore it usually affects only babies born under 28 weeks. Their lungs remain stiff, and a chest X-ray shows up changes typical of this condition. If this is the case, the baby may need to stay on a ventilator or on oxygen for possibly weeks, or even months.

The membrane lining a babys lungs is very delicate. Long term use of mechanical ventilation causes damage to this membrane. The result can be inflammation, followed by the formation of areas of fibrous scar tissue in the lungs. As a result, the lungs become stiffer than normal. Some areas of healthy tissue will remain, this is what the baby utilises to breathe. This is also what gives the patchy appearance on the sick baby's x-rays. Gradually over time healthy tissue grows and replaces the fibrous tissue, and the x-rays will return to normal.