Infants may require cardiorespiratory monitoring in the home for a variety of problems that affect breathing. Apnea monitors do not prevent SIDS and are not prescribed for that purpose. Because apnea is relatively common in preterm infants, it is the focus of this article.
Apnea is any pause in breathing (respirations) and may cause oxygen desaturation (too little oxygen available to the tissues). Bradycardia is a slowing of the heart rate below what’s normal for the baby’s age and may be accompanied by cyanosis (a blue color of the lips or mucous membranes). Before discharge, the medical team will have ruled out other physiologic causes for your baby’s apnea, such as anemia, gastroesophageal reflux disease, bronchospasm related to underlying bronchopulmonary dysplasia, or seizures.
Babies diagnosed with apnea of prematurity are often treated in the NICU with medications such as theophylline or caffeine, which help stimulate the respiratory center in the brain. Babies who have frequent episodes of apnea and bradycardia are not discharged, even with an apnea monitor, until the episodes resolve or become less severe. In most cases, babies outgrow apnea and bradycardia. Clinical observation usually determines whether your baby is breathing well enough on her own to be discharged safely. Newer NICU monitors are able to document breathing and heart rate trends over time, which also validates readiness for discharge.
Some units may perform a sleep study, also called polysomnography, pneumocardiogram, or pneumogram, before discharge to monitor your baby’s breathing and heart rate more over a 12- or 24-hour period. A pneumogram uses a monitor similar to your baby’s cardiorespiratory monitor but with additional channels that record your baby’s heart rate, respirations, airflow through the nose, and oxygen saturation. If gastroesophageal reflux is suspected as a cause of apnea and/or bradycardia, an additional probe is used to record the acidity of secretions in the esophagus. The baby is attached to this special monitor for a specified period, usually overnight, and specially trained personnel analyze the results. This may help determine the sequence of events that leads to, or triggers, an apneic/bradycardic episode. Institutions vary in their use and interpretation of pneumograms. Many hospitals do not use them at all, but rely heavily on your baby’s clinical history (recent episodes) to determine the need for home apnea monitoring.
If the baby is still having significant apneic, bradycardic, or desaturation episodes and is otherwise ready for discharge, a home apnea monitor is ordered from an outside company (sometimes referred to as a vendor or a durable medical equipment [DME] company) and delivered to the hospital before your baby’s discharge. Your discharge planner, case manager, or social worker coordinates this process. The vendor instructs parents in the use of the apnea monitor before the baby’s discharge and provides an instruction manual and a phone number for monitor problems once you are home.
The vendor should encourage parents to ask questions. Some hospitals require that parents spend a night rooming-in with their baby before discharge to ensure that the monitor is working properly and that the parents feel comfortable and competent in its operation. Rooming-in is also excellent for practicing the routine care, feedings, and other specialty care (such as medication administration) your baby may need. You will learn how to respond to monitor alarms and when to notify your doctor about unusual events. You will also have a chance to get to know your baby’s behavior on a 24-hour basis, with nurses and doctors nearby to answer questions.
If your baby has come home with an apnea monitor, you’ll want to use it whenever you or your baby is sleeping and when you are busy. It’s acceptable to take the monitor off when you’re playing with your baby during more alert periods and when you’re bathing your baby. This gives her skin a break from the belt that secures the monitor. The belt can irritate her skin, especially when the weather is warm. If electrodes are used in place of a belt, they should be changed according to the schedule stated by your health care provider. Because electrodes are adhesive, removing them too frequently, or keeping them in the same place too long, can also irritate your baby’s skin.
With advances in monitoring technology in the hospital and improvements in management of apnea of prematurity in general, fewer babies are actually being discharged with home apnea monitors today than a decade ago. When babies are sent home on monitors, parents are often relieved. It makes them feel more secure. After about a week, though, they’re ready to throw the monitor out of the window because false alarms are driving them crazy. False alarms are usually set off by abdominal breathing or by a loose belt or incorrectly placed monitor electrodes (leads). The frequency of false alarms tends to increase as a baby grows older and becomes more active. Ignoring the alarms or assuming them to be false can be potentially dangerous.
Health care providers may ask you to keep a log (record) of alarms at home to help them determine when to discontinue monitoring and/or medications. Most babies who come home on both monitor and medications are allowed to outgrow the dose of medication, provided the apnea and bradycardia episodes diminish and then stop. When your baby has been free of apnea and bradycardia for a designated period, your health care provider will stop the medication. The apnea monitor is frequently continued for another month or two. If no episodes of apnea or bradycardia are recorded, the monitor may then be discontinued. Some health care providers will request a “monitor download” (or record of apnea and bradycardia events) from the DME company before stopping the monitor. Occasionally, a home pneumogram may be done immediately before monitor use is stopped, but this is becoming rare due to lack of payment for this diagnostic test in the home environment from insurance companies and government assistance programs.
An apnea monitor usually has 3 alarms: for apnea, slow heart rate, and fast heart rate. Your health care provider tells the equipment company what alarm settings to use for your baby. Typically, the apnea alarm is set at 15 seconds; slow heart rate, at 80 beats per minute; and fast heart rate, at 210 to 230 beats per minute. The alarm limits are lowered as your baby gets older.
Apnea monitor alarm signals are very loud. It is therefore very important that the apnea monitor not be placed directly next to your baby’s head, in order to protect your baby’s delicate hearing. Sometimes, the loudness of the apnea monitor alarm itself will startle the baby awake and restart breathing or stop the bradycardia that may have been the cause of the alarm in the first place. Parents sometimes wonder if this was a false alarm, but it is important to check every alarm signal regardless. Therefore, if you are in the shower or vacuuming or performing some other function that might impair your ability to hear your baby’s apnea monitor alarm, you may want to use your home baby monitor (kept at the instructed distance from the apnea monitor so the frequencies do not interfere with the monitoring of your baby) as an extra amplifier for the alarm signal.
As with anything electrical, you need to take certain precautions if your infant has a home apnea monitor. Your baby should not be left unsupervised with other children. Infants have been electrocuted by older siblings placing their lead wires into a wall socket. Most monitors today have a protective covering over the lead wires to prevent this from occurring. If your baby’s monitor does not have this safety feature, ask for a safer model. Even with a protective design, older children should be specifically warned not to handle the monitor.
Your health care provider will give you letters to send to your telephone company, electric company, and local emergency medical service (EMS) system, alerting them that you have an infant with special needs in your home. This puts your home on a priority list in the event of a power outage or medical emergency.