Apnea of prematurity

Apnea is breathing that slows down or stops from any cause. Apnea of prematurity refers to short episodes of stopped breathing in babies who were born before their due date ( premature ).

Most preterm and some sick full-term babies have some degree of apnea.

Causes

There are several reasons why newborns, in particular those who were born early, may have apnea, including:

• If their brain is not fully developed
• If the muscles that keep the airway open are weak

Other stresses in a sick or premature baby may worsen apnea, including:

• Anemia
• Feeding problems
• Heart or lung problems
• Infection
• Low oxygen levels
• Temperature problems

Symptoms

The breathing pattern of newborns is not always regular and may be called "periodic breathing." This pattern is even more likely in newborns born early (preemies).

This irregular pattern is felt to be normal, but also thought of as immature.

It consists of short episodes (about 3 seconds) of either shallow breathing or stopped breathing (apnea). These episodes are followed by periods of regular breathing lasting 10 to 18 seconds.

Apnea episodes that last longer than 20 seconds are considered serious. The baby may also have a:

• Drop in heart rate. This heart rate drop is called bradycardia.
• Drop in oxygen level (oxygen saturation). This is sometimes called a "desat."

Exams and Tests

These babies will be placed on monitors in the hospital.

• The monitors keep track of their breathing, heart rate, and oxygen levels.
• Apnea, drop in heart rate, or drop in oxygen level can set off the alarms on these monitors.

Drops in heart rate and oxygen levels may occur for other reasons than apnea (such as passing stool or moving around), so the monitor tracings are most often reviewed by the health care team.

Treatment

How apnea is treated depends on the cause, how often the breathing stops, and the severity of episodes. Babies who appear to be otherwise healthy and have few episodes per day are simply watched. They can be gently shaken during periods when breathing stops.

Babies who are well, but who have many episodes in which they stop breathing, may be given caffeine. This will help stimulate their breathing. Sometimes, the nurse will change a baby's position, use suction to remove fluid or mucus from the mouth or nose, or use a bag and mask to help with breathing.

Proper positioning, slower feeding time, oxygen, and (in extreme cases) a breathing machine ( ventilator ) may be needed to assist in breathing.

Some infants who continue to have apnea will be discharged from the hospital on a home apnea monitor, with or without caffeine, until they have outgrown their immature breathing pattern.

Outlook (Prognosis)

Apnea is common in premature babies. Most babies have normal outcomes. Although mild apnea does not appear to have long-term effects, most doctors agree that preventing multiple or severe episodes is better for the baby over the long-term.

Apnea of prematurity most often goes away by the baby's 36th week, but may last as long as the 44th week, especially in infants who were born very prematurely.