Read about apnea of prematurity, which is a condition in which premature babies take unusually long pauses (usually more than 20 seconds) between breaths.
Key points
Apnea of prematurity affects almost all premature babies born before 28 weeks and 50 per cent of infants born at 30 weeks.
Very premature babies who have prolonged pauses in their breathing may develop a slowing of their heart rate and a drop in their oxygen levels.
Treatment includes respiratory assistance and caffeine.
As very premature babies mature, they experience fewer apneic episodes and outgrow apnea of prematurity prior to discharge home.
Introduction
It is common for premature babies to have breathing that is not as regular as full-term babies. This is called periodic breathing: moments when the time between breaths is longer than what would normally be expected. If these intervals between breaths extend for longer than 20 seconds, the baby is classified as having apnea. At times, these pauses are accompanied by a slowing of the heart rate, which is called bradycardia, and a drop in oxygen saturation.
More information
What is apnea of prematurity?
Apnea of prematurity is caused by a premature baby’s immature drive to breathe. They have yet to develop their lung’s response to messages from their brain. They may also have difficulty keeping their nose and upper airway open. A premature baby’s immature brain is not programmed to breathe regularly until 34 weeks of age or later since the placenta is doing all the functions of the lung before a fetus is born.
Apnea is categorized in several ways:
Central apnea has a primarily neurological cause: the part of the brain that controls the breathing mechanism is immature and not functioning perfectly. Usually, it is just a matter of time until the brain catches up and begins to regulate breathing properly.
Obstructive apnea is caused by some blockage of the airway. Eliminating the blockage will reduce symptoms.
Mixed apnea is a combination of both central and obstructive apnea.
As premature babies mature, the systems that control breathing and keep their airways open also mature.
Diagnosis
How apnea of prematurity is diagnosed
While premature babies may experience apnea of prematurity, apnea may be a symptom of other conditions. Babies with infections, breathing difficulties, low body temperature, neonatal seizures or low blood glucose may experience apnea as a way of showing the health-care team that something is wrong. Often, screening tests are done for babies with apnea to exclude other causes.
Apnea of prematurity usually begins during the first days of a very premature baby’s life. The baby may have only one or two episodes a day, or as many as a dozen. As the baby’s brain matures, the condition disappears, usually with no more episodes when the baby’s breathing centre has fully matured, usually between 36 and 40 weeks’ gestational age.
Treatment
Treatment of apnea of prematurity
Very premature babies who are more at risk for frequent episodes of apnea are treated with medication to help stimulate them into regular breathing. Caffeine is typically used. In small amounts, the kick or stimulus produced by caffeine is usually enough to keep the baby breathing regularly. Many of these very premature babies are also provided with respiratory support for their apnea of prematurity even though they have minimal or no lung disease. The respiratory support may include nasal continuous positive airway pressure (CPAP), BiPAP or intubation of the airway with mechanical ventilation. These treatments are continued until a baby matures and their condition is stable.
Other treatment strategies include treating other causes of apnea, ensuring a baby’s nose is not obstructed and their head and neck are properly positioned.
Premature babies in the Neonatal Intensive Care Unit (NICU) have their heart and breathing rates and oxygen saturation constantly monitored. If apnea occurs, the baby’s health-care providers will be immediately alerted to it. Usually, it only takes a small amount of physical stimulation to get the baby to begin regular breathing again. A gentle stroking of the skin is often sufficient.
Long-term outcomes
Long-term outcomes
Most babies who are treated for apnea of prematurity improve by about 36 weeks’ gestation. Caffeine is usually discontinued by that time and babies are monitored for five to seven days off caffeine before discharge home to ensure that no further apnea events occur when the medication is discontinued.
