A central venous catheter (CVC), otherwise called a central line (C-Line), is a catheter that is set into a huge vein. It is usually given for the purpose of accessing the vein. For critically ill patients and for those who require intravenous therapies for a long time, larger catheters are placed.  Where the catheters are put are in the inner jugular vein, subclavian vein, femoral vein, and through the veins in the arms known as a PICC line (incidentally embedded catheters).

The size of Catheters that are most commonly used ranges in size between 15-30 cm in length.  It is made of silicone or polyurethane and has either single or different lumens of implantation.

Why are central lines important for pediatric cancer patients:

For children who have required chemotherapy treatment, maintaining intravenous (IV) access is highly challenging. To make the process easier, there are various devices available and the type of device that is chosen is based on the type of therapy that the child is to undergo and the duration of it. It can also be according to the personal preference of the patient. 

What are the common types of central lines that are available?

External catheters – these catheters are tunneled underneath the skin and are placed in a major blood vessel by surgical means. Most commonly external catheters are placed in the chest. The reason why they are called external catheters is that a portion of these catheters is exposed outside the body for the purpose of allowing its use without a needle stick. In the place where the catheter is placed through the skin, there should be a clean dressing at all times that should be changed regularly as per the advice of your healthcare team. When using this type of catheter, a family member must learn to administer heparin to keep it functioning efficiently and free from infection. The frequency at which it should be administered can be determined by your child’s healthcare specialists. Family members are also taught and trained to change the dressing in between treatments. 

Subcutaneous ports: these are surgically placed devices that are completely implanted into the subcutaneous tissue and are most often placed in the chest. The nested catheter is inserted into a major blood vessel. A special ‘Huber’ needle is what is used for purposes of inserting through the skin and then into the post by the doctor before the part is ready for use. Once the insertion and the placement process are complete, a dressing is required. The dressing should be very clean, sterilized, and changed quite regularly. Both the catheters are used in a similar manner for administering intravenous infusion to the child getting treated for cancer.

What are the risks of catheter use?

Insertion of central lines can have several problems and can even lead to certain complications. But it is to be noted that the benefit of catheter usage always outweighs the risks.

Pneumothorax:

This condition emerges because of the catheterization of the subclavian veins because of its nearby anatomic closeness to the peak of the lung. By making use of the ultrasound guidance, the potential risk of causing a pneumothorax is minimized due to the catheterization being done in the internal jugular vein. Those specialists who have been in the field for so long and are highly experienced have a pneumothorax incidence of about 1- 3%. To minimize the implications that arise due to this procedure, various medical organizations have advised the routine usage of ultrasonography.

If a person is suspected of having pneumothorax, an upright x-ray of the chest should be done and the purpose being this upright position is to migrate the free air to the apex of the lungs that can be visualized easily. This is not possible to be performed in patients who are older or are more critically ill in the ICU. 

Vascular perforation:

This type of catheter insertion is the most feared and rightly so because it is potentially life-threatening even if a slight complication happens. 

However, the frequencies of such occasions are very uncommon because of the lines being set with the direction of an ultrasound. One such potential incident that may occur is the accidental cannulation of the carotid artery in the internal jugular vein, the rate at which this accident occurs is 1% even under the guidance of an ultrasound. Under conditions of the carotid being unintentionally cannulated and a catheter is embedded, don’t attempt to eliminate it as it very well may be deadly. Notify a vascular surgeon. 

Bloodstream infections:

Notwithstanding how profoundly cleaned a catheter might be, it brings microbes into the circulation system while being embedded. The microscopic organisms’ attack can cause genuine diseases that can be deadly in practically 25% of the cases. Bloodstream infection caused due to central line association has gained huge attention in recent times due to it causing a high number of deaths and morbidity that results in increased health care costs. It is to be noted that microbes do not enter the body through contaminated infusions. One possible way for them to gain access to the human body is through the lumen of the catheter. They have break points called the hubs and they migrate along with the position thus reaching the subcutaneous tissue until they reach the vein. Likewise, the microbes present in the blood will likewise connect to the outer layer of the catheter in this manner changing it into a central point of the disease.

On the off chance that there is contamination thought in the individual to whom the ventral lines ought to be given, their blood societies are taken from both the catheter and the vein. Quantitative blood culture is exceptionally exact yet not a technique is generally drilled.

For individuals who are thought to have a catheter-related circulation system disease, anti-toxins are controlled right away. However, these should be done only after conclusive results are drawn from the blood culture else the organism responsible for the infection may not be found. 

Coagulase-negative staphylococci, for example, staphylococcus epidermidis are the most widely recognized creature that is liable for causing these diseases. The disease that is brought about by Staphylococcus aureus is bacteremia which requires the expulsion of the catheter from the body and admission of anti-infection agents. Catheter evacuation without giving the right anti-infection agents can make individuals foster endocarditis. Studies have shown that managing anti-infection agents in patients might not have any advantage regardless of whether the treatment includes the use of the drawn-out central venous catheter and it doesn’t forestall gram-positive catheter-related diseases. On the other hand, patients requiring the assistance of a central venous catheter for the long term are more vulnerable to developing infections and can be administered antibiotics based on the recommendation from their doctor.

Rigid cleaning of the catheter addition site is encouraged to diminish contamination. The product generally used for such cleaning processes is the Povidone-iodine solution. Chlorhexidine is also twice as effective as the former.  Supplanting the lines regularly apparently affects keeping such diseases from occurring. Given below are some of the guidelines recommended by the CDC to reduce the risk due to CVCs, 

• The location that is highly preferred for insertion is the subclavian vein to avoid infection happening due to point of view and also to avoid the femoral vein
• On account of a tunneled catheter site, there are no reasonable proposals in the rule
• When choosing a catheter try to pick one that has negligible ports to achieve the clinical objectives.
• Always use sterile gloves when handling such situations
• A full body sterile drape, mask, cap, and gloves are mandatorily required when placing a CVC visual monitoring of the catheter site should be done and palpitation on an irregular basis should be done to assess the possibility of an infection
• While changing the dressing of the catheter insertion site, it is not that important that you wear a full body sterile suit but make sure to use clean and sterile gloves
• The chlorhexidine  cleansers are highly preferred but chlorhexidine  and povidone-iodine usage are also acceptable
• The straightforward dressing for momentary CVC ought to be changed at regular intervals and the cloth dressing ought to be changed like clockwork.
• Long-term catheters require the dressing change to be done something like once every week except if it becomes dirty or loose.
• Do not remove or replace the CVC catheter. 
• Yet, central line catheters ought to be eliminated when they are of no utilization. There is no such thing as scheduled removal and replacement of CVC will avoid the possibility of an infection. 
• If the dressing contains medications, then there are possibilities that the risk of an infection might be reduced
• There is no such thing as regular changing of dressings for central venous access devices that may cause fewer infections and whether the skin cleaning antiseptics reduce the rate of bloodstream infection caused due to catheter placement. 

Occlusion

It is a type of apoplexy where a fibrin sheath structures around the catheter and is a typical reason for catheter deterrent. This is known to be made in venous catheters due to the discharge of blood into the catheter that prompts apoplexy or a mixture of insoluble from the hastens of the prescription taken. Apoplexy is the most widely recognized reason for central line impediment which represents around 25%. On account of CVCs, the gamble factors are very high because of the blood coagulating that prompts the furthest point profound vein apoplexy. The gamble is because of the enactment of the thickening substances and it is higher in disease patients. Reviews show that close to 66% of disease patients show proof of catheter-related apoplexy yet go undetected generally speaking.

Frequently asked questions:

What is the use of a  central venous catheter?

Also known by the name central line, central venous catheters are tubes that are placed by doctors in a large vein, specifically in the chest, or arms to give fluids, blood, or medications into the body. It is even done for the purpose of doing medical tests quickly. The catheters are long and flexible and empty in or near the heart region allowing the necessary treatment to be given within seconds. It is quite different from the normal intravenous lines. The intravenous line is to give medicine near the surface of the skin for a short time while CVCs are venous catheters that are placed in the body for months or weeks through which treatment is provided several times a day. They play a vital role in treating various conditions, especially in the intensive care units. 

What is a central venous catheter used for?

The following are the reason why a CVC is used for, 

• To administer medicines for infection, pain treatments, or other medical issues
• To provide nutritional fluids 
• For the purpose of conducting certain medical tests.

What are the different types of central venous catheters?

There are various types of CVC available. The type that is recommended will be decided by your healthcare provider depending on the condition of each patient, 

• Peripherally inserted central catheter (PICC) line – Placed into the vein in the arm
• A tunneled catheter – Placed into the chest or neck surgically and then passed under the skin. The medicines are given right into the catheter through the end that comes out. 
• An implanted port – is like that of a tunneled catheter however this is set totally under the skin. The medicine is given by a needle placed through the skin. This is not visible as the tunneled catheter does not need daily care and does not cause any discomfort while the patient is going about their regular activities. 

Where are the central venous catheters used?

These are mostly used in hospitals, especially in the intensive care units, special care units, long-term care facilities such as ambulatory surgical clinics, and dialysis centers that have outpatient facilities. CVC can be administered at home for some patients too after they come back from their stay at the hospital, especially when getting treated for conditions like cancer