A central venous catheter (CVC), also known as a central line (c-line), central venous line, or central venous access catheter, is a catheter placed into a large vein. It is a form of venous access. Placement of larger catheters in more centrally located veins is often needed in critically ill patients, or in those requiring prolonged intravenous therapies, for more reliable vascular access. These catheters are commonly placed in veins in the neck (internal jugular vein), chest (subclavian vein or axillary vein), groin (femoral vein), or through veins in the arms (also known as a PICC line, or peripherally inserted central catheters).
Central lines are used to administer medication or fluids that are unable to be taken by mouth or would harm a smaller peripheral vein, obtain blood tests (specifically the "central venous oxygen saturation"), administer fluid or blood products for large volume resuscitation, and measure central venous pressure. The catheters used are commonly 15–30 cm in length, made of silicone or polyurethane, and have single or multiple lumens for infusion.
The following are the major indications for the use of central venous catheters:
Difficult peripheral venous access – central venous catheters may be placed when it is difficult to gain or maintain venous access peripherally (e.g. obesity, scarred veins from prior cannulations, agitated patient).
Delivery of certain medications or fluids – medications such as vasopressors (e.g., norepinephrine, vasopressin, phenylephrine etc.), chemotherapeutic agents, or hypertonic solutions are damaging to peripheral veins and often require placement of a central line. Additionally, catheters with multiple lumens can facilitate the delivery of several parenteral medications simultaneously.
Prolonged intravenous therapies – parenteral medications that must be delivered for extended periods of time (more than a few days) such as long-term parenteral nutrition, or intravenous antibiotics are administered through a central line.
Specialized treatment – interventions such as hemodialysis, plasmapheresis, transvenous cardiac pacing, and invasive hemodynamic monitoring (e.g. pulmonary artery catheterization) require central venous access.
There are no absolute contraindications to the use of central venous catheters.Relative contraindications include: coagulopathy, trauma or local infection at the placement site, or suspected proximal vascular injury.However, there are risks and complications associated with the placement of central lines, which are addressed below.
What should I pay attention to during the CVC insertion process?
Infection control: Prior to CVC insertion, healthcare providers should practice proper hand hygiene and adhere to strict infection control measures. This includes wearing sterile gloves, masks, caps, and gowns, using sterile drapes to cover the patient, and maintaining sterile technique throughout the insertion process.
Appropriate site selection: Selecting the appropriate insertion site, such as subclavian vein, internal jugular vein, or femoral vein, based on the patient's specific condition and needs. Proper site selection can improve the success rate of catheter insertion and reduce the risk of complications.
Local anesthesia: Local anesthesia is typically administered prior to CVC insertion to minimize patient discomfort and pain. Anesthetic agents are commonly used through local injection or topical anesthesia.
Implement sterile technique: During CVC insertion, healthcare providers should adhere to sterile technique, including using sterile puncture needles and guidewires, avoiding contamination of the insertion site, and ensuring all instruments and materials used are sterile.
Monitoring and guidance: Real-time monitoring devices, such as ultrasound, can aid in determining the correct insertion position. Guidewires are used to navigate the catheter through the blood vessels.
Ensure patency and securement: After CVC insertion, ensure proper blood return and perform an X-ray to confirm the correct position of the catheter. Additionally, use appropriate securement devices, such as sutures or transparent dressings, to secure the CVC in place and prevent dislodgement.
Infection prevention: Once the CVC is inserted, take appropriate infection prevention measures, such as regular dressing changes, maintaining cleanliness and dryness at the insertion site, and adhering to the recommended time frame for CVC replacement.
