Central Venous Access Devices

Central venous access devices (CVADs) are commonly used in interventional radiology procedures for various purposes. CVADs provide long-term access to the central venous system, allowing for the administration of medications, fluids, blood products, and parenteral nutrition. They are also used for hemodynamic monitoring, frequent blood sampling, and hemodialysis.

There are different types of CVADs used in interventional radiology, including:

Peripherally Inserted Central Catheter (PICC): A PICC line is inserted into a peripheral vein (typically in the arm) and advanced until the tip reaches a central vein, such as the superior vena cava or the right atrium. PICC lines are often used for long-term intravenous therapy and can remain in place for weeks to months.

Central Venous Catheter (CVC): A CVC is inserted into the internal jugular vein and positioned in the central vein. This type of catheter is typically used for patients requiring short-term access for venous access.

Portacath: An implanted port consists of a reservoir that is surgically placed under the skin, usually in the chest or upper arm, and connected to a catheter that is threaded into a central vein. The port is accessed using a needle, which is inserted through the skin and into the reservoir. Implanted ports are commonly used in patients who require intermittent long-term access, such as those receiving chemotherapy.

Dialysis Catheter: Dialysis catheters are specialized CVADs used for hemodialysis. They have two lumens, one for blood withdrawal and the other for returning the filtered blood. These catheters are inserted into a central vein, often in the neck or groin, and are used for temporary dialysis access.

Imaging guidance is used, including angiography/fluoroscopy and ultrasound, to ensure the accurate placement of the catheter tip within the desired central vein. Proper care and maintenance of CVADs are essential to minimize complications such as infection, thrombosis, and catheter malfunction.

A&I Protocol

PICC Line Preparation and Exam:

Patient is lying supine on the angiography table with their arm (preferably left arm unless contraindicated, such as cardiac pacemaker, lymphadectomy and poor veins) supported on a sponge and arm board. Right arm is used if contraindicated.
The radiographer marks the arm vein, usually the basilic vein. If thrombosed, blocked or small, followed by marking the brachial vein or cephalic vein.
Sterile preparation of setup and PICC line.
Seldinger technique is used to access the vein under ultrasound guidance.
Under fluoroscopy guidance, the wire is visualised in the thorax and the tip at the cavo-atrial junction.
The PICC line length is measured using the external markers on the wire. Hence, the PICC line is cut and advanced over the wire and through the peel away sheath.
The wire is removed, sheath peeled away and the PICC line secured intravascularly, using fluoroscopy to ensure that the PICC line catheter tip is at the cavo-atrial junction.
A DSA run or fluoroscopy capture with Iodine contrast is used to confirm the PICC line position, with the contrast flowing from the right atrium, to right ventricle and into the pulmonary arteries.
The PICC line insertion site is cleaned and dressed.

Central Venous Catheter Preparation and Exam:

Patient is lying supine on the angiography table, with the patient's head and neck supported by a square sponge and head turned to the left with right internal jugular vein for access.
Sterile preparation of set up and CVC.
Seldinger technique is used to access the right internal jugular vein under ultrasound guidance.
The wire is advanced and directed down the superior vena cava (SVC) and towards the cavo-atrial junction, using fluoroscopy guidance.
The peel away sheath is tracked over the wire, and the wire removed and CVC advanced through the sheath.
Fluoroscopy visualises the CVC tip at the cavo-atrial junction. A DSA run or fluoroscopy capture is used to confirm the CVC final position with Iodinated contrast.
The CVC line insertion site is cleaned and dressed.

Port-a-cath Preparation and Exam:

Patient is lying supine on the angiography table, with the patient's head and neck supported by a square sponge and head turned to the left with right internal jugular vein for access.
Sterile preparation of set up and Port-a-cath.
Seldinger technique is used to access the right internal jugular vein under ultrasound guidance.
The wire is advanced and directed down the superior vena cava (SVC) and towards the cavo-atrial junction, using fluoroscopy guidance.
The right side of the chest wall is prepared for the Port-a-cath insertion and anchoring.
The Port-a-cath is tunnelled from under the chest wall and through to the access point near the right internal jugular vein.
The peel away sheath is tracked over the wire, and the wire removed and Port-a-cath catheter advanced through the sheath.
The sheath is peeled away.
Fluoroscopy is used to visualise the Port-a-cath tip at the cavo-atrial junction. A DSA run or fluoroscopy capture is used to confirm the Port-a-cath final position with Iodinated contrast.
The Port-a-cath insertion sites (chest and neck) are cleaned and dressed.

Dialysis Preparation and Exam:

Patient is lying supine on the angiography table, with the patient's head and neck supported by a square sponge and head turned to the left with right internal jugular vein for access.
Sterile preparation of set up and Port-a-cath.
Seldinger technique is used to access the right internal jugular vein under ultrasound guidance.
The wire is advanced and directed down the superior vena cava (SVC) and towards the cavo-atrial junction, using fluoroscopy guidance.
The right side of the chest wall is prepared for the Dialysis catheter tunnelling from under the chest wall and through to the access point near the right internal jugular vein.
Three levels of dilators are used to dilate the tract of the internal jugular vein.
The peel away sheath is tracked over the wire, and the wire removed and Dialysis catheter advanced through the sheath.
The sheath is peeled away.
Fluoroscopy is used to visualise the Dialysis cathter tip at the cavo-atrial junction. A DSA run or fluoroscopy capture is used to confirm the Dialysis catheter final position with Iodinated contrast.
The Dialysis catheter insertion sites (chest and neck) are cleaned and dressed.

Common central venous access devices including PICC lines, Portacath and CVC.

DSA or Portacathogram showing the flow of contrast through the Portacath and into the right atrium of the heart.

(Left) Transverse ultrasound showing the triad for PICC line access: brachial nerve bundle, brachial artery (pulsatile), and brachial vein underneath (compressible using the probe).

(Right) Longitudinal ultrasound of a basilic vein for PICC line puncture and access.

References

Lockwood J, Desai N. Central venous access. Br J Hosp Med (Lond). 2019 Aug 2;80(8):C114–9.
Saugel B, Scheeren TWL, Teboul JL. Ultrasound-guided central venous catheter placement: a structured review and recommendations for clinical practice. Crit Care. 2017 Aug 28;21(1):225.
Wadełek J. Haemodialysis catheters. Anestezjol Intens Ter. 2010;42(4):213–7.
Sansivero GE. Features and selection of vascular access devices. Semin Oncol Nurs. 2010 May;26(2):88–101.
Moureau N, Chopra V. Indications for peripheral, midline and central catheters: summary of the MAGIC recommendations. Br J Nurs. 2016 May 28;25(8):S15-24.