What Is a UAC?
A UAC (Umbilical Arterial Catheter) is a small, flexible tube placed into one of the arteries in a newborn baby's umbilical cord.
It allows the NICU team to monitor blood pressure and collect blood samples without repeatedly sticking your baby with a needle.
UACs are most commonly used for premature or critically ill newborns who need frequent monitoring.
A UAC helps the healthcare team closely monitor your baby's condition while reducing the need for repeated blood draws.
Why Does My Baby Need a UAC?
Some babies require frequent blood tests and continuous blood pressure monitoring during the first days of life.
A UAC can be especially helpful when a baby:
Is born very prematurely
Needs significant breathing support
Requires frequent blood gas measurements
Has unstable blood pressure
Needs close monitoring because of a serious medical condition
The UAC provides a reliable way to collect important information while minimizing repeated needle sticks.
How Is a UAC Placed?
After birth, a small portion of the umbilical cord remains attached to your baby's abdomen.
The umbilical cord contains three blood vessels: two arteries and one vein.
The healthcare provider carefully inserts a thin catheter into one of the umbilical arteries and advances it into the appropriate position.
The procedure is performed using sterile technique to reduce the risk of infection.
After placement, the team confirms the catheter's position, usually with an X-ray.
The catheter is then secured to help prevent movement.
Although the remaining umbilical cord itself does not have pain-sensitive nerves, babies may experience discomfort from handling and other parts of the procedure. The team provides appropriate comfort measures.
What Is a UAC Used For?
A UAC has two primary purposes.
1. Continuous Blood Pressure Monitoring
The catheter can be connected to a monitoring system that measures blood pressure directly from an artery.
This provides continuous information about your baby's blood pressure rather than relying only on occasional measurements from a blood pressure cuff.
2. Blood Sampling
A UAC allows the team to collect blood samples for tests such as:
Blood gases
Blood glucose
Electrolytes
Other laboratory tests when appropriate
Blood gases are especially important for babies receiving respiratory support because they help the team evaluate oxygenation, ventilation, and acid-base balance.
What Does a UAC Look Like?
You may notice a thin tube coming from your baby's umbilical area.
The catheter is connected to tubing containing fluid and may be attached to a blood pressure monitoring system.
The NICU team carefully secures the catheter and tubing to reduce the risk of accidental movement.
A small amount of fluid continuously flows through the system to help keep the catheter open.
The team regularly checks the tubing, connections, and insertion site.
Can I Hold My Baby With a UAC?
This depends on your baby's condition and your NICU's policies.
Some NICUs allow carefully supervised holding or skin-to-skin care with an umbilical arterial catheter in place, while others limit movement because of the risk of catheter displacement or bleeding.
Your baby's overall stability and the security of the line are important considerations.
Always ask your baby's nurse before attempting to reposition, lift, or hold your baby while a UAC is in place.
Even when holding is temporarily limited, you may still be able to participate in comforting your baby through gentle touch, talking, or other developmentally appropriate care.
How Does the NICU Keep My Baby Safe?
Because a UAC is placed inside an artery, it requires careful monitoring.
The NICU team routinely assesses:
The catheter insertion site
Blood flow and circulation to the legs and feet
Skin color and temperature
Blood pressure readings
Signs of bleeding or infection
Catheter position and tubing connections
These checks help identify potential problems early.
Are There Risks Associated With a UAC?
Like any catheter placed into a blood vessel, a UAC has potential risks.
These include:
Infection
Bleeding
Blood clot formation
Reduced blood flow to certain areas of the body
Catheter movement or incorrect positioning
Serious complications are uncommon but can occur.
The healthcare team carefully weighs the benefits of the catheter against these risks and removes it when it is no longer needed.
How Long Will My Baby Need a UAC?
A UAC is generally used for a relatively short period, often during the first several days of life.
The exact length of time depends on your baby's medical condition, how frequently blood samples are needed, and whether continuous blood pressure monitoring remains necessary.
NICUs follow established protocols regarding how long umbilical arterial catheters may remain in place.
Once your baby no longer needs the catheter, the healthcare team removes it.
What Is the Difference Between a UAC and a UVC?
You may hear your baby's healthcare team discuss both a UAC and a UVC.
Although both are placed through the umbilical cord, they serve different purposes.
UAC — Umbilical Arterial Catheter
Placed into an umbilical artery
Used for continuous blood pressure monitoring
Allows frequent blood sampling
UVC — Umbilical Venous Catheter
Placed into the umbilical vein
Used to administer IV fluids and medications
May be used to provide parenteral nutrition
Some babies have both catheters in place at the same time.
What Can Parents Ask?
If your baby has a UAC, consider asking:
Why does my baby need a UAC?
What information are you monitoring through the catheter?
How often are blood samples being collected?
Is my baby able to be held while the line is in place?
How long do you expect the UAC to remain?
What needs to happen before it can be removed?
What Should Parents Know?
A UAC is a specialized catheter that helps the NICU team monitor your baby's blood pressure and obtain important blood tests.
Although seeing a catheter coming from your baby's umbilical area may feel concerning, it can reduce the number of needle sticks your baby needs during a critical period.
A UAC is usually temporary and is removed when your baby no longer requires that level of monitoring.
Your baby's healthcare team will regularly assess whether the catheter is still necessary.
