NICU Glossary

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Adjusted age (or corrected age) – The age that a premature baby would be if he or she had been born on his or her due date.

Anemia – A condition in which you lack enough healthy red blood cells to carry adequate oxygen to your body’s tissues.

Antepartum – Before birth. An expectant mother may be admitted to the antepartum unit should she require specialized in-hospital care prior to being ready to deliver.

APGAR – A test given soon after birth that evaluates on a scale of 1-10 how a newborn baby adjusts to the environment outside the uterus immediately after delivery.

Apnea – A pause in breathing that lasts for more than 20 seconds, or is accompanied by a slow heart rate (bradycardia) or a change in skin color. Apnea is common among preemies who still have immature control of their breathing.

A’s and B’s – Referring to apnea and bradycardia.

Arterial line – A small, short, plastic catheter that is put through the skin into an artery of the arm or leg. Also referred to as a peripheral arterial line (PAL).

Asphyxia – A lack of oxygen supply to body tissues. Asphyxia can have negative effects on all of the organs, including the brain. Asphyxia can occur in the womb, during delivery, or immediately after birth.

Aspiration – 1. Breathing a foreign substance such as meconium, formula or stomach contents into the lungs;  2. Withdrawal of material (i.e. mucous) from the body by suctioning



Bagging – filling the lungs with air by pumping air and/or oxygen into the baby’s lungs via a bag that’s connected to an endotracheal tube or attached to a mask fitted over baby’s face.

Bilirubin lights (phototherapy) – Special lights used to treat jaundice. Also referred to as bili lights.

Bilirubin – A substance produced during the normal breakdown of red blood cells. If a baby’s liver isn’t mature enough to get rid of bilirubin in the bloodstream, jaundice, a yellowing of the skin and whites of the eyes, can occur. When very high levels are present, brain damage can result.

Blow-by oxygen – the nurse or doctor has an oxygen mask and passes it in front of the child’s face.

Blood gas – A blood test used to evaluate an infant’s level of oxygen, carbon dioxide, and acid. This helps to evaluate an infant’s respiratory status.

Bonding – The process by which parents and baby become emotionally attached

BPD (bronchopulmonary dysplasia) – See Chronic Lung Disease (CLD)

Bradycardia (“brady”) – A slowing of the heart rate, usually to less than 80 beats per minute for preemies and infants.

Brain bleed – Bleeding into the fluid-filled areas (ventricles) inside the brain.

Bronchoscopy – A procedure that involves looking inside a baby’s trachea and bronchi (the large airways of the lungs) with a fiber optic scope, to see whether there is a problem that is making breathing more difficult

Bronchopulmonary dysplasia (BPD) – a term used to describe long-term breathing problems for premature babies. (See also Chronic Lung Disease (CLD))


NICU Glossary Hand to Hold


Caffeine – used to treat or prevent respiratory and lung problems in premature babies and to reduce the length of time that they need assistance with their breathing.

Cannula – A device used to give supplemental oxygen when needed. A thin flexible tube goes over the baby’s face and head, with two prongs that go into the baby’s nostrils. The cannula is connected to an oxygen source, and a flow meter regulates the amount of oxygen that is given to the baby

Cardiopulmonary resuscitation (CPR) – A method of reviving a person whose heartbeat and breathing has stopped or slowed abnormally

Catheter – a flexible tube inserted through a narrow opening into a body cavity, particularly the bladder, for removing fluid.

Central line – An intravenous line that goes all the way up to a vein near the heart or just inside the heart. A central line delivers medicine, fluids, blood, or nutrition. A PICC line (peripherally inserted central catheter) is a type of central line that is placed in one of the major blood vessels.

Cerebral palsy (CP) – A group of disorders that affect a person’s ability to move and maintain balance and posture. CP is the most common motor disability in childhood. Cerebral means having to do with the brain. Palsy means weakness or difficulties with using the muscles.

Chest tube – a surgically-inserted plastic tube that is used to drain fluid or air from the chest so the lung can expand. Air or fluid (for example blood or pus) that collects in the space between the lungs and chest wall can cause the lung to collapse.

Chorioamnionitis – An infection of the amniotic fluid and sac

Chronic lung disease (CLD) – Chronic lung disease is the general term for long-term breathing problems in premature babies. It is also called bronchopulmonary dysplasia (BPD).

Colostrum – Breast milk produced in late pregnancy or in the first three to five days after delivery. This milk is usually yellowish in color and is especially rich in nutrients and antibodies.

Congenital diaphragmatic hernia (CDH) – A type of birth defect in which some of the organs that are normally found in your baby’s belly move up into the chest cavity through a hole in the diaphragm, causing poor development of the lung on one or both sides

Congestive heart failure (CHF) – a serious condition in which the heart doesn’t pump blood as efficiently as it should to the rest of the body. This could be due to a weak heart muscle or to a structural problem causing the heart to pump inefficiently. Despite its name, heart failure doesn’t mean that the heart has literally failed or is about to stop working.

Containment hold – A containment hold is done by using your hands to hold your baby still, gently but firmly, and restraining their arms and legs if they are showing jerky, disorganized movement. A containment hold provides secure boundaries to help your baby feel safe and secure.

Continuous positive airway pressure (CPAP) – Pressurized air, sometimes with additional oxygen, that is delivered to the baby’s lungs to keep them from collapsing as the baby inhales and exhales; usually delivered by nasal prongs or face mask

Corrected age/adjusted age – The age a premature baby would be if he had been born on his due date. Corrected age is calculated by taking the baby’s actual age and subtracting the number of weeks or months he was born premature. (For example, a baby whose actual age is 12 weeks, but was born 4 weeks premature, is 8 weeks corrected, or 8 weeks adjusted.)

Cyanosis – a bluish discoloration of the skin resulting from poor circulation or inadequate oxygenation of the blood.



Desaturation or “De-satting” – A drop of oxygen levels in the baby’s bloodstream.

Developmental care – An approach to caring for premature babies that stresses their individual needs and aims to decrease stress. Developmental care may include meeting babies’ comfort needs, helping babies feel secure, helping babies develop normal sleep patterns, decreasing stimulation from noise, lights, or procedures

Developmental delay – A delay in one or more areas of emotional, mental, or physical growth, in comparison to most other children of the same age. In preemies, developmental delays may be short term or long term.

Diuretic – A medication that increases the amount of water that passes out of the body through the urine

Down syndrome – A chromosomal abnormality often caused by an extra copy of chromosome 21. This extra copy changes how the baby’s body and brain develop, which can cause both mental and physical challenges for the baby. Also known as trisomy 21.



Echocardiogram – An echocardiogram checks how the heart’s chambers and valves are pumping blood through the heart. An echocardiogram uses electrodes to check the heart rhythm and ultrasound technology to see how blood moves through the heart, in an effort to diagnose possible heart conditions.

Edema – Fluid retention in the body tissues that causes puffiness or swelling

EEG (electroencephalogram) – A test that detects abnormalities in the brain waves, or in the electrical activity of the brain. Electrodes consisting of small metal discs with thin wires are pasted onto the scalp and detect tiny electrical charges that result from the activity of the brain cells.

EKG (electrocardiogram) – A procedure that measures electrical signals in the heart, to see if the heart is beating at a normal rate and strength.

Electrodes – Small patches taped to the baby’s chest, arms or legs connected to a monitor to measure the heart and breathing rates

Electrolytes – Chemicals that, when dissolved in water, can conduct an electrical current. (The main electrolytes in the human body are sodium, calcium and potassium. They play important roles in the proper functioning of the cells.)

Endotracheal tube (ET Tube) – A plastic tube inserted into the baby’s trachea (windpipe) to help the baby breathe. You will not hear the baby cry while this tube is in place. See also intubation.

Extubation – The removal of the endotracheal tube



Fontanel – The “soft spot” on the top of the baby’s head between the un-joined sections of the skull



Gastrostomy – A surgically created opening in the abdominal wall to provide nutrition directly to the stomach when the esophagus is blocked or injured, or to provide drainage after abdominal surgery

Gastroesophageal reflux – Often referred to as “GE reflux,” or just “reflux,” this is a condition in which the contents of the stomach comes back up through the esophagus. It is similar to heartburn in adults.

Gavage feeding – A method of feeding breast milk or formula through a small tube (called a nasogastric or NG tube) placed through the baby’s mouth or nose that leads into the stomach

Gestation – The length of time between the first day of the mother’s last menstrual period before conception and the delivery of the baby

Gestational age – The length of time from conception to birth. A full-term infant has a gestational age of 38-42 weeks.

Gram – A unit of measuring weight; 30 grams = 1 ounce. Babies in the NICU are weighed daily, and their weight is recorded in grams.



Head ultrasound (HUS) – A painless test that uses sound waves to look at a baby’s brain. 

Heel stick – A method of obtaining blood samples by pricking the baby’s heel

Hernia – A weakness in the abdominal wall that causes a portion of the intestines to protrude into the umbilical or inguinal area (This may also occur with a problem of the diaphragm that causes the bowel to enter the chest cavity, resulting in underdevelopment of the lung.)

High-frequency oscillatory ventilator – A special ventilator capable of breathing for a baby at rates exceeding those of a normal ventilator (see also: oscillating ventilator)

High-risk (at-risk) – Refers to persons or situations needing special intervention to prevent illness, damage or death, or to keep illness or damage from worsening; for example, high-risk newborns, high-risk pregnancies

Hydrocephalus – The buildup of fluid in the cavities (ventricles) deep within the brain. The excess fluid increases the size of the ventricles and puts pressure on the brain. Cerebrospinal fluid normally flows through the ventricles and bathes the brain and spinal column.

Hyperbilirubinemia – Excess bilirubin in the blood; a condition common in newborns

Hypotension –Low blood pressure.



I and O – Abbreviation for “input and output,” referring to the amount of fluids given by oral feedings or by IV, and the amount of fluid excreted in the urine or stools, as well as blood removed for testing, over a given period of time.

Infusion pump – A pump that is attached to an IV line to give fluids to the baby in tiny, carefully measured amounts

Intracranial hemorrhage (ICH) – Bleeding in or around the brain

Intrauterine growth restriction (IUGR) – A condition in which a baby isn’t growing to normal weight during pregnancy, according to their gestational age. Can be caused by various conditions of the mother or baby.

Intravenous (IV) therapy – The delivery of fluids, blood, or medication directly into a patient’s system through the veins. NICU babies may receive IV therapy to administer essential fluids and electrolytes, blood transfusions, or medications.

Intraventricular hemorrhage (IVH) – bleeding inside or around the ventricles in the brain. Bleeding in the brain can put pressure on the nerve cells and damage them. Severe damage to cells can lead to brain injury.

Intubation – The insertion of a tube into the trachea (windpipe) to allow air to reach the lungs to help with breathing

Isolette (Incubator) – A transparent plastic box that has a heating system to keep premature babies warm. (Isolettes used to be called incubators.)



Jaundice – A yellowish color of the skin and whites of the eyes,  caused by a buildup of bilirubin in the body. (See also Hyperbilirubinemia)

Kangaroo care – Also known as skin-to-skin contact or kangaroo mother care, kangaroo care involves direct contact when a newborn is placed skin-to-skin on mom or dad’s bare chest, inside the shirt, or covered by a blanket, like a baby kangaroo in his mother’s pouch



Lactation – Production of milk by the breasts

Lactation consultant – a certified health professional who specializes in breastfeeding issues

Lead wires – Wires that lead from the electrodes to a monitor

Let-down reflex – Release of milk into the milk ducts and down to the nipple. Let-down can often cause a tingling feeling.

Low birth weight infant (LBW) – a baby is born weighing less than 5 pounds, 8 ounces (2500 grams). The baby can be premature or full term.



Meconium aspiration – Breathing in of amniotic fluid that contains the baby’s stool passed before or during delivery

Murmur (heart murmur) –  A heart murmur is an extra sound in the heartbeat — such as a ”whooshing” — that is caused by turbulent blood flow through the heart. This may be normal or abnormal.



Nasal cannula – A set of plastic prongs and tubing that delivers extra oxygen into a baby’s nose.

Naso-gastric tube (NG tube) – A small plastic tube inserted through the nose or mouth and into the stomach used for feedings when an infant is unable to breastfeed or drink from a bottle.

Nebulizer – a small machine that turns liquid medicine into a mist, so medicine goes into the lungs as the baby breathes.

Necrotizing enterocolitis (NEC) – affects mostly the intestines of premature infants, in which Parts of the bowel are damaged or destroyed because of poor blood flow, inflammation or infection.)

Neonatal period – The first 30 days of life

Neonatologist – A pediatrician who has special training in newborn intensive care

Neonate – A baby during the first 4 week of life

Newborn intensive care unit (NICU)– An intensive care unit with trained staff and equipment to care for ill or premature newborn infants.

NPO – Stands for “nil per os”, which means “nothing by mouth.” If an infant is NPO, he or she is not getting any medicines or nutrients by mouth.



Occupational/Physical Therapist (OT/PT) – A health professional who helps patients improve the way their nervous system functions. An occupational therapist plans exercises to help development, improve muscle control, and solve feeding problems.)

Oral-gastric (OG) tube – A soft tube that goes through a baby’s mouth down into his stomach, used for feeding or to empty the stomach of gas.

Omphalocele – A condition of the abdominal (belly) wall in which the infant’s intestines, liver, or other organs stick outside of the belly through the belly button. in which the intestines push through an opening in the abdominal wall

Oscillating ventilator – Also called a high-frequency ventilator, it works differently than a regular ventilator. An oscillating ventilator keeps a baby’s lungs filled with air all the time by giving tiny amounts of air at very rapid rates.

Oximeter/Pulse oximeter – A monitoring device used to show the level of oxygen in a baby’s blood. (This device is taped to the skin, usually a finger or foot, for oxygen level readings.)



Parenteral nutrition (PN) or total parenteral nutrition (TPN) – Feeding of nutrition by IV, rather than through the stomach and the intestines

Patent ductus arteriosus (PDA) – A heart defect found in the days or weeks after birth. The ductus arteriosus is a blood vessel in the fetus that allows oxygen-rich blood from the placenta to bypass the left side of the heart and lungs to the rest of the body. The ductus arteriosus usually closes in the first two weeks of life in full-term infants. In the preterm infant, it may stay open and need to be closed with surgery.

Peripheral IV – An IV line that goes into “peripheral” veins. These veins are the small blood vessels near the skin’s surface, usually in the baby’s arms, legs or scalp.

Peripherally Inserted Central Catheter (PICC Line) – A long, thin tube that’s inserted through a vein – usually in the baby’s arm – and passed through to the larger veins near the baby’s heart. Generally used to give medications or liquid nutrition, a PICC line can help avoid frequent needle sticks and reduce the risk of irritation to the smaller veins in the arms.

Phototherapy – A treatment for jaundice with a special type of light (not sunlight) that aims to lower the bilirubin levels in your baby’s blood through a process called photo-oxidation.

Physical therapist (PT) – A therapist who treats problems of coordination and of the large motor skills

PKU- Metabolic Screen/Newborn Screening – A blood test done on special paper that tests for several different genetic disorders. It is often done 24-72 hours after birth and repeated on preemie babies at 2 weeks and 4 weeks of age.

“Priming the Gut” – A slang phrase often heard in the NICU to describe the slow starting of feeds to get the digestive system ready to start functioning fully. 

Pulse Oximeter – See Oximeter



Radiant warmer – An open bed with a heat source that allows immediate access to newborn and sick preemies while maintaining a warm air temperature.

Respiratory distress syndrome (RDS) – A breathing disorder in newborns caused by immature lungs. Symptoms include rapid, shallow breathing and a sharp pulling in of the chest below and between the ribs with each breath.

Reflux – A backward flow of stomach contents, generally referring to a type of spitting up or regurgitation common in premature infants.

Residuals – The contents from a prior feeding left inside the belly at the start of the next feeding.

Retinopathy of prematurity (ROP) – An eye disorder that primarily affects premature infants weighing about 2.75 pounds (1250 grams) or less that are born before 31 weeks of gestation. Characterized by abnormal eye blood vessel growth.

Respiratory syncytial virus (RSV) – A highly contagious virus that affects the respiratory tract. It is most common in the fall and winter months, when colds are more prevalent. In most people RSV presents like a normal cold, but it can be more serious in premature babies, causing infections such as pneumonia or bronchiolitis.



Sepsis – An infection of the blood or other tissue.

Shunt – A hollow tube surgically placed to help drain fluid and redirect it to another location.

Sudden infant death syndrome (SIDS) – The death of an infant during sleep from unknown causes.

Steroid – A drug given to reduce inflammation, especially in the throat, trachea and lungs.

Suctioning – The process of removing secretions from the baby’s nose, mouth or lungs by using either a bulb syringe or suction catheter.

Surfactant – A substance produced by the lung that serves as a coating in the air sacs and keeps the tiny air sacs open between breaths. The lungs of premature infants often do not make enough surfactant, which can lead to poor lung function. Surfactant can be administered through a breathing tube.



Tachycardia – A fast heart rate.

Tachypnea – A fast breathing rate.

Term infant/full term infant – An infant born between 38 and 42 weeks of gestation.

Thrush – A fungal (yeast) infection that can grow in the mouth, throat and other parts of a baby’s body.

Total parenteral nutrition – See Parenteral nutrition

Transfusion – A treatment in which red blood cells are added directly to the baby’s total circulating blood supply through an IV or a catheter. Most commonly, blood is transfused to treat symptoms caused by anemia, such as apnea or bradycardia commonly seen in premature babies.

Twin-to-twin transfusion syndrome (TTTS) – A rare pregnancy condition affecting identical twins in which there is an imbalance in the blood exchange between the twins via the connecting blood vessels in the shared placenta. One twin — the donor twin — gives away more blood than it receives in return and runs the risk of malnourishment and organ failure. The recipient twin receives too much blood and is susceptible to overwork of the heart and other cardiac complications.



Umbilical Artery Catheter/Umbilical Vein Catheter (UAC/UVC ) – A soft plastic tube inserted into an artery or vein in the baby’s navel to give IV fluids or medications, to monitor blood pressure, and to obtain blood for tests.



Ventilator – A breathing machine to which the baby is connected by an endotracheal tube (a plastic tube placed into the windpipe through the mouth or nose). The amount of oxygen, air pressure and number of breaths per minute can be regulated to meet each baby’s needs.

Ventricle – 1. A small chamber, as in the ventricles of the heart; 2. Small chambers in the center of the brain where cerebrospinal fluid is made.

Ventriculo-peritoneal (VP) shunt – A thin plastic tube that helps drain extra cerebrospinal fluid (CSF) from the brain., used for long-term treatment for hydrocephalus.

Wean – To take away gradually. In the NICU, it is often used to describe the process of removing an infant from a ventilator or incubator.


This page was last modified on Oct 19, 2023 @ 4:03 pm. If you see any information that needs to be updated or corrected, please contact