Central Venous Access
A central venous access catheter (CVAC) is a tube that is inserted beneath your skin so there is a simple, pain-free way for doctors or nurses to draw your blood or give you medication or nutrients. When you have a CVAC, you are spared the irritation and discomfort of repeated needle sticks. More than 3.4 million CVACs are placed each year and doctors increasingly recommend their use.
Doctors often recommend CVACs for patients who regularly have:
- Chemotherapy treatments
- Infusions of antibiotics or other medications
- Nutritional supplements
Select from the below to learn more:
Catheter Placement and Removal
CVACs are increasingly used for a variety of indications including hemodialysis, parenteral nutrition, and the long-term administration of chemotherapeutic, antibiotic, or anti-fungal agents. Central venous access can be achieved by interventional radiologists from both peripheral and central veins using a variety of techniques to insert a wide array of catheters and ports. Approximately 3.4 million CVACs are placed in patients in the United States each year.
In many institutions, interventional radiology placement is the method of choice. There are a number of advantages to placing central venous access devices in the interventional radiology suite, including higher technical success rates. The rate of successful placement with image guided techniques approaches 100 percent compared to 44–74 percent for surgical placement via cutdown of the cephalic vein, and 92–100 percent for other surgical techniques.
Modern angiographic materials also provide improved safety and efficacy during access to the venous system compared with historical access procedures.
Use of small needles, better access devices, and ultrasound or contrast-enhanced fluoroscopic guidance techniques that allow accurate visualization of the target vein, lead to improved success.
Interventional radiology techniques also allow for greater precision. With fluoroscopic guidance, the catheter tip can be directed into the optimal position within the venous system. By avoiding surgical cutdown techniques, which are more likely to result in sacrifice of the vein, radiologic placement preserves future access and decreases patient discomfort.
Other advantages include shortened procedure times and decreased costs. Placement in the interventional radiology suite typically requires one-third to one-half the time needed for surgical placement.
Dialysis/pheresis catheters are used to “clean” the blood in patients with kidney failure requiring hemodialysis or patients with immune diseases requiring plasma pheresis. These treatments require rapid flow of blood in and out of the body.
Selecting the appropriate central venous access device depends on the frequency, type, and length of therapy; the patient’s level of activity; and the patient’s ability to perform routine catheter care.
Device types include:
- Non-tunneled catheters, which are designed for short- or intermediate-term access. These include standard, triple lumen CVACs and peripherally inserted central catheter (PICC) lines.
- Externally tunneled catheters, which are designed for at-home or long-term use. These are appropriate when continuous or frequent access is required, when high flow rates are needed, as for hemodialysis or apheresis, and when patients are particularly adverse to frequent needle sticks.
- Subcutaneous ports, which are totally implantable devices. These are implanted in the chest wall or upper extremity for long-term, intermittent use.
Methods of Placement
Percutaneous placement of catheters requires venous access, tunnel or subcutaneous pocket formation, if needed, and positioning of the catheter within the central venous system. Venous access is typically guided with contrast-enhanced fluoroscopy or ultrasound. Conventional central venous access sites include the axillosubclavian, and internal and external jugular veins. Typical peripheral venous access sites include the basilic, cephalic, and brachial veins in the upper extremity.
Unconventional sites include the inferior vena cava, hepatic veins, collateral veins, and occluded venous segments.