Overview of Umbilical Vein Catheterization
Umbilical vein catheterization is a method used by doctors to get quick access to the bloodstream of a newborn baby, for up to 14 days after birth. This technique is used as an emergency route to deliver medications and fluids into the baby’s body, particularly during medical recovery. It is most often used in the delivery room, but a trained healthcare professional can perform the procedure if needed.
While the most preferred method to give medications to a newborn is through a peripheral intravenous line (a tube inserted into a vein in the arm or leg), healthcare providers who take care of newborns should be skilled in multiple techniques for gaining access to a vein. These include using a needle to get into a bone (intraosseous lines), inserting a tube into a larger, central vein (central venous catheters), and accessing the umbilical vein at the belly button.
An intraosseous line often can be placed more quickly than an umbilical vein catheter. However, there can be challenges in placing an intraosseous line in a newborn, and there’s a risk it may accidentally come out during an emergency. That makes umbilical vein catheterization an appealing method, if the medical staff is fully trained to do it.
Anatomy and Physiology of Umbilical Vein Catheterization
The umbilical cord, which connects a baby to its mother while inside the womb, develops from the yolk sac and a part called the allantois about five weeks into pregnancy. Throughout the pregnancy, the umbilical cord remains roughly the same length as the developing baby, from head to bottom. When a baby is born, its umbilical cord is normally around 2 centimeters wide and 50 centimeters long. This cord has to be clamped and cut at birth.
The umbilical cord includes two umbilical arteries and one umbilical vein. You can identify the umbilical arteries by their smaller inner space and thicker walls. The umbilical vein, normally found at the top, has a thicker inner space and a thinner wall than the arteries. If a doctor places a tube, known as a catheter, in the umbilical vein, it should ideally go from the vein to a vessel known as the ductus venosus, and end in a large vein called the inferior vena cava, just underneath the right upper chamber of the heart.
Why do People Need Umbilical Vein Catheterization
A doctor might need to insert a special type of IV, called an umbilical vein catheter, into a newborn baby if the baby needs help like medicine given directly into the vein, help breathing, or needs blood. This kind of IV is usually used when other IVs are hard to place.
On top of this, the experts at McMaster University have found that certain babies can really benefit from these types of IVs. This includes very premature babies who are less than 28 weeks old, babies who are 29 weeks or older and need help breathing or are receiving high levels of oxygen, and babies who are 29 weeks or older but are having problems with their heart and blood flow.
When a Person Should Avoid Umbilical Vein Catheterization
The process of inserting a catheter, which is a thin, flexible tube, into the umbilical vein, should not be done in certain situations. Particularly, it cannot happen if a patient has gastroschisis (an abdominal wall defect where the infant’s intestines are outside of their body), omphalitis (an infection of the umbilical cord stump), omphalocele (a birth defect where an infant’s intestine or other abdominal organs are outside the body at birth), peritonitis (an inflammation or infection of the lining of the inner wall of the abdomen), vascular compromise (a condition affecting the blood circulation), or necrotizing enterocolitis (a serious disease affecting the intestine of premature infants).
Equipment used for Umbilical Vein Catheterization
Here’s what medical professionals use when they’re performing this procedure:
* A radiant warmer: it’s an equipment to help keep the baby’s body temperature stable during the procedure.
* A clean gown, gloves, cap, and mask to ensure everything is sterile when performing the procedure.
* Sterile drapes: these are used to cover the baby while still providing a clean, sterile working area for the procedure.
* Bactericidal solution: a substance used to kill bacteria and make sure the area is as clean as possible.
* An umbilical tape: this is used to secure the catheter once it’s placed.
* Scissors, a scalpel, and different kinds of forceps for cutting and holding tissue.
* Umbilical vein catheter: a small tube that’s inserted into the baby’s umbilical vein to deliver medications, fluids or to draw blood.
* A three-way stopcock and IV tubing: these help control the flow of fluids through the catheter.
* A Needle driver (a tool that holds the needle) and a 3-O silk suture (a very fine thread used for stitching wounds).
* Sterile saline flush: a solution used to clean and rinse the catheter.
Choosing the right size catheter for a baby depends on how much they weigh. If a baby weighs less than 3.5 kg (or about 7.7 pounds), medical professionals will likely use a 3.5 French catheter. For babies who weigh 3.5 kg or more, they’ll probably use a 5 French catheter. After picking the right size, they’ll rinse the catheter with a saline solution and use a 10-cc syringe and a three-way stopcock to control its usage during the procedure.
Who is needed to perform Umbilical Vein Catheterization?
For this procedure – putting in a catheter (a small tube) into an umbilical vein – a specialized doctor, a medical trainee, or a skilled healthcare provider should be the one to perform it. It’s necessary for there to be another person, like a nurse or medic, on hand, too. Their role is to keep a close eye on you during the whole process and to help with making you comfortable and handling the medical supplies.
Preparing for Umbilical Vein Catheterization
Before beginning a medical procedure on a newborn, several important steps need to be checked and completed. All necessary equipment should be gathered and thoroughly inspected to ensure it’s in working condition. Any available medical test results need to be reviewed for better understanding of the baby’s health status.
Before the procedure starts, parents or guardians will need to give their formal written consent. This is after the doctor has explained to them the potential risks and benefits as well as other alternative treatments that might be possible instead of this procedure. Of course, if there’s a medical emergency, the procedure may have to be carried out immediately regardless.
Before starting the procedure, the medical team typically has a ‘time-out’. This is not a break or rest, but a final, careful verification step to confirm the identity of the correct patient and to double-check whether there are any reasons why the procedure shouldn’t be done.
This procedure is performed inside a piece of equipment called a ‘radiant warmer’, which is like a baby-friendly incubator. This helps to maintain a stable, warm environment for the baby so they don’t get too cold while the procedure is taking place.
Before the catheter (a small, flexible tube used for medical procedures) is used, it is flushed with saline (salt water solution) mixed with a substance called heparin. This helps to remove any air bubbles and also prevents the blood from clotting and blocking the catheter.
Finally, a device called a ‘three-way stop-cock’ is attached to the catheter. This useful tool allows doctors to control the flow of fluids during the procedure.
How is Umbilical Vein Catheterization performed
Firstly, the surrounding skin of your baby’s umbilical stump will be cleaned with a germ-killing solution. A special kind of surgical tape is then positioned at the spot where the skin meets the umbilical stump. Sterile drapes will be used to keep the area clean. Using non-sharp forceps, the doctor will then take hold of the umbilical stump and lift it in order to straighten it out.
To make accurate identification and cannulation (insertion of flexible tube) of the umbilical vein easier, a horizontal cut will be made through the umbilical stump, about 1 to 2 cm from the skin. This helps unveil the not dried part of the umbilical cord.
There are two umbilical arteries and one umbilical vein present in the cord, the arteries can be recognized by their thicker walls and the vein is usually positioned at 12 o’clock and has thinner, larger walls. To control any bleeding, the surgical tape can be tightened. Gentle use of iris forceps (small pair of tweezers) can help open and widen the umbilical vein and also clear any blood clots inside it.
A catheter will then be gently inserted into the umbilical vein. The umbilical vein catheter (UVC) will be held firmly at the base of the umbilicus with the left hand. The catheter will be filled with saline (salt solution) before being inserted into the vein. Depending on the baby’s maturity, the insertion depth may differ, typically 3 to 5 cm for a full-term baby and 2 to 4 cm for a premature baby. Blood return will also be checked.
If the doctor meets any resistance, they will loosen the surgical tape and try to gently insert the catheter again. If resistance is still felt, the procedure will be stopped and another method of placing a catheter will be sought. However, if the line placement is for emergency access, the catheter is usually inserted about 1 to 2 cm past the point where blood return was initially noticed.
In cases where the line placement is for long-term access, the line is usually extended to be just beneath the heart’s right atrium. Usually, this is about 10 to 12 cm in a full-term baby. This catheter would be considered a “central venous catheter” and is suitable for monitoring pressure in the large veins or for infusing special medications. If this is the case, an X-ray will be taken to make sure that the catheter is positioned correctly. Standardized guides and formulas based on the baby’s birth weight and other factors, can help estimate how far the catheter should be inserted.
Once the catheter is in place, it can only be withdrawn – not advanced further. Secure the catheter using a suture through the cord. The umbilical stump and catheter will then be covered with a clear dressing for extra protection against movement. To confirm the correct positioning of the catheter, a thoracoabdominal x-ray or abdominal sonography may be performed, usually the latter is preferred.
Possible Complications of Umbilical Vein Catheterization
As with all procedures involving central veins (the large veins that carry blood directly to your heart), there can be complications. These can include severe bleeding, infection, damage to nearby areas, blood clots, and accidentally placing the tube in an artery instead of a vein. Specifically for tubes called umbilical vein catheters, one risk is that the tube might be inserted into the portal venous system. This network of veins carries blood to the liver and if concentrated solutions leak out here, it might cause liver tissue death.
In some cases, liver abscess (a pocket of pus), blood clots in the portal vein, and cavernoma (abnormal blood vessels) formation have been reported. Given the small volume of a newborn’s veins, these tubes must be carefully flushed with a saline solution to ensure there is no air inside them. This is because any trapped air could travel up the tube into the bloodstream leading to an air embolism (a blockage), a life-threatening condition.
If the tube is accidentally inserted into the umbilical artery, it can block the blood supply to a limb or form a clot, causing the tissues of the limb to not get enough blood (limb ischemia). If the catheter goes too far and enters the right atrium of the heart, it can cause a hole and leak fluid into the sac that surrounds your heart.
A baby whose circulation becomes unstable after placement of an umbilical vein catheter should be checked for cardiac tamponade (a serious condition where fluid builds up around the heart), which could restrict the heart’s function. However, these risks are similar to other tubes placed via the skin directly into a vein. Reports indicate that umbilical vein catheters carry a lower risk of blood clots and blocked iliofemoral veins (a condition where the main veins in your legs get blocked) compared to femoral central venous catheters, another type of tube that’s placed in the vein in your leg.
What Else Should I Know About Umbilical Vein Catheterization?
Placing a catheter (a small, flexible tube) into the umbilical vein is a trusted method for quickly gaining access to the bloodstream in newborns up to 14 days old. This procedure can help in administering medications or treatments during an emergency.
