Central Venous Access Catheter
What is a central venous access?
What is a central venous access catheter?
What type of patients receive central venous access catheters?
How are these devices inserted?
How do I prepare for central venous access?
What happens after the procedure?
What are the risks of central venous access?
It refers to the placement of a small tube (also known as a catheter), which is placed into a vein either in the neck or upper chest. This vein can be used to administer medications or nutrients or can be used to withdraw blood without the need for frequent venous puncture. Previously, surgery was required to insert these tubes however today these procedures can be done without the need for surgery by an interventional radiologist.
A central venous catheter (CVC) is a tube that is inserted beneath your skin into the veins enabling a simple pain free way for doctors or nurses to withdraw your blood or give you medication or nutrients. When you have a CVC, you are spared the irritation and discomfort of repeated needle sticks. More than 3.4 million CVCs are placed each year and doctors increasingly recommend their use for patients with a large variety of medical conditions. There are several types of CVCs including tunneled catheters (Hickman), peripherally inserted central catheters (also know as PICC lines or long lines), dialysis catheters, and implantable ports. Most CVCs consist of a catheter with a tip located within the large vein in your chest. These catheters can either be inserted via the large vein in the neck (internal jugular vein) or the vein draining one of your arms (subclavian vein). In most cases, the tube will exit onto the skin or may be tunneled under the skin before it exits onto the skins surface. These tubes may remain in situ for up to several months.
Doctors often recommend CVCs for patients who regularly have:
- Chemotherapy treatments
- Infusions of antibiotics or other medications
- Nutritional supplements
- Hemodialysis
How are these devices inserted?
The procedure may take place either as an out patient procedure or after you have been admitted to hospital. Placement of the device takes place in the radiology department. You will be lying on an x-ray table. Your doctors may decide to give you medication to make you sleepy during the procedure. The area chosen for skin puncture will be cleaned and you will be covered with sterile towels.
Your doctors will inject local anaesthetic into the skin at the puncture site. This will sting, although this sensation wears off after a minute or so. After the local anaesthetic has been injected, you should feel little more in terms of discomfort.
In most cases, the doctors will gain access to your veins using ultrasound. This enables the doctor to visualise very clearly the site and course of your veins enabling him to easily pass a needle into the vein through the skin. Once the needle tip has entered the vein, he will pass a wire (known as a guidewire) followed by a small tube. This tube will be advanced into the large vein in the chest (superior vena cava). If the CVC is a tunneled device, the doctor may inject more local anaesthetic under the skin passing away from the entry site into the vein. After this has been done, the doctor will pass the tube that has entered the vein under the skin so that the proximal end of the tube exits from a site in the skin at a distance away from its entry point into the vein. At the end of the procedure, your doctor will probably elect to suture the end of the tube in place. You may be able to go home the same day or your doctors may require you to stay in hospital overnight.
There is no specific preparation required. If you are taking drugs that thin the blood such as Warfarin, your doctors may ask you to stop these tablets a few days before the procedure. On the day of the procedure, you may be allowed a light breakfast. Most physicians require a period of food restriction for 2-4 hours before these devices are placed.
If the doctors have given you medications to make you sleepy during the procedure, you may feel drowsy for a few hours after the device has been placed. Once you are awake, you can eat and drink as normal. You may feel discomfort at the site of the puncture site for a few days after the procedure.
There are few risks associated with this procedure. Very rarely, your doctors may pass needles into structures apart from the veins. This is very unusual because they use ultrasound to visualise the veins to prevent this possibility. In the unlikely event that a needle passes into another organ, worrisome complications arising from this are extremely uncommon.