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Having a premature baby is scary. That’s kind of a given. I’m not going to get into all of the crazy thoughts and feelings that you go though when coming to terms with your individual situation, because that’s a different topic all together. (If you’d like to read about what I experienced, you can click here.) One word I have heard across the board though, is “scary”. And, while it is scary, knowing some of the key NICU terms that the doctors and nurses are throwing around can help ease the fear, confusion and uncertainty a bit.
This of course won’t make everything better, but I feel you are anything like me, the more knowledge about the situation that you can absorb, the better you feel. Even if the answer is not good, it eases my anxiety to know the answer.
So, here is a list of five terms that you should know as you are adjusting to a baby in the NICU.
1. N.I.C.U.
Let’s start at the beginning. N.I.C.U stands for Neonatal Intensive Care Unit. This is the section of the hospital reserved for just-born babies. Babies who have not yet entered the world outside. I didn’t find out until Alice was adjusted age two months and going back to the hospital for surgery, that once graduated from NICU, babies can’t come back. They are then sent to the PICU (pediatric intensive care unit). The NICU is a sterile environment, so only just-born babies who have not gone home yet will be there.
Babies are brought down to the NICU for a variety of reasons, and for any complications from birth. The largest population however, is preemies. (Babies born before 37 weeks gestation) Parents and other family members are able to visit, but there are strict rules around who can come and go, when visiting can happen, and how you wash up before entering. Make sure you fully understand the rules of your NICU, and don’t be afraid to ask for clarification about anything. All of the rules are in place for the safety of your child, and others.
2. Adjusted Age and Gestational Age
“Adjusted Age” or “Age-Adjusted” is the age your preemie would be if they were born full term. For this, you go by their due date. However, most of the time in the NICU you will be going by their gestational age. So for example, if you would’ve been 32 weeks pregnant today but your child was already born, today their GA would be 32 weeks. Once you get to their due date, you start using adjusted age. So if your child was due a week ago today, their adjusted age is one week. This is the age your doctors will be going by for all developmental milestones and for evaluating size.
Most doctors stop using adjusted age around 2 years old, when children tend to be caught up to their full-term counterparts in size and development. This of course varies by child and is only a generalization, as with everything for preemies- everyone is on their own journey.
3. A and Bs
Apnea (a pause in breathing) and Bradycardia (a slow heart rate)-also called “Brady’s”
A and Bs are common in preemies. They are one of the most common problems that preemies face, and are one of the scariest- only because every time your child has one, the alarms start going off. These ‘episodes’ are only really cause for concern for doctors if they are constant, severe, or appear to be related to an underlying issue. Most of the time, the nurses will just come in and pat your baby to get them going again.
4. Pulse Ox, O2 sat, Desatting
Ok, so this is 3 words, but they all go together hand in hand. “Pulse Ox”is short for Pulse Oximeter. This is a tiny strip of tape or bandage, wrapped around your child’s foot (most likely) with a wire attached to it. It is checking the amount of oxygen in your baby’s blood. Information from this is crucial to knowing if your baby needs help breathing, or if they are starting to get too much oxygen (that’s a thing for preemies!). This also helps the doctors know when your baby is stable enough to step down on breathing assistance.(More on that later)
“O2 sat” is medical lingo for oxygen saturation. In other words, the percentage of oxygen in your baby’s blood.
Finally, “desatting” is oxygen desaturation. It’s when the oxygen saturation in your baby’s blood dips below a certain percentage, that has been set by the doctors and nurses to alarm. (Usually around 77% if your child is still receiving respiratory help) Again, just like As and Bs, this is rather common in preemies. While it can signify an underlying cause, but doesn’t always.
When it comes to apneas, bradys and desats, I learned in my time in the NICU that when alarms start going off- look at your baby, not the machines. Often, leads can come off, or just be worn out. Sometimes your baby skipped a breath, but he is already breathing fine again. Sometimes your baby startles and it makes her heart skip a beat, but she’s really ok. The machines are wonderful to get your attention, it’s your baby that will tell you whether something is really wrong.
5. Isolette
An isolette is a covered, heated crib. These are used for preemies that are too young or sick to be able to regulate their own body temperature. Seeing Alice in one made me uncomfortable because I didn’t know if I could open it, or touch her. Most likely you can, just make sure to check with your nurse about specific precautions you should be taking. Don’t be afraid to ask! Remember it is your baby in there- you are allowed to ask to touch and hold them!
6. Vent, CPAP and Cannula
Again, three words, but all connected. Pretty much, they are all way to help your baby breathe.
“Vent” is short for ventilator. The ventilator is the strongest, most intensive breathing support. This is when they “intubate” (throwing in an extra word for you…) and put a tube down into the lungs. The vent then breathes for your child. There are different types of ventilators and different settings based on what your child needs, so it’s good to ask questions of your nurses and doctors about the vent your child is on,
CPAP stands for Continuous Positive Airway Pressure. It is basically a machine that provides a strong, steady flow of oxygen through nasal prongs. It keeps the air sacs open even when the baby isn’t exhaling, to make each breath easier. This is a step down from the ventilator, although it can also be set up to provide “breaths” to your child.

“Cannula” or nasal cannula, is another step down from CPAP. It is possible to have it be “high-flow” so that it almost matches the pressure of a CPAP to keep the airways open, but not all cannulas do that. A big difference between the Cannula and CPAP is that the Cannula’s nasal prongs are smaller, and so the air coming from them mixes with room air. It is the last option before having your child on just room air.
These are just a handful of the terms you will learn through your time in the NICU with your child.
Especially if you are there for weeks or months. Don’t be afraid to ask questions of your nurses and doctors to make sure you understand. The more understanding you have of the super scary terms, the less scary they are.

A wonderful reference book that helped me along our journey was Preemies by Dana Wechsler Linden, Emma Trenti Paroli, and Mia Wechsler Doron, M.D.
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Read more about our journey, the NICU and preemies in these articles:
The Day My Daughter Almost Died- Alice’s Fight With NEC (Part 1)
September is NICU Awareness Month. Here are the FAQs.
This is a great article for parents facing the NICU! The A’s and B’s and noises of the monitors were in my dreams for months after we left the NICU.
Thanks! I just remember trying to get all the basics down, but everything is so overwhelming coming at you at once! I hoped pulling out the basics might make it easier for some.