Implantable ports, also known as chemoports, totally implantable central venous access ports or Port-A-Caths, are a type of central venous catheter for patients requiring long-term venous access. They offer long-term central venous access, which is one of the advantages over peripherally inserted central catheters (PICC).

Indications

Similar to peripherally inserted central catheters (PICC), implantable ports are primarily inserted to provide long-term central venous access. This is particularly useful for patients who require:

• long-term intravenous administration of medication (e.g. chemotherapy or antibiotics)

• peripheral access where standard intravenous cannulae insertion is difficult or impossible

• to withdraw blood from the body in patients who require frequent blood tests

In comparison to peripherally inserted central catheters (PICC):

• implantable ports can last up to several years; PICC lines last for several weeks or months

• while PICC lines require daily flushing and dressing, implantable ports require less frequent since they are under the skin

• implantable ports are waterproof while a PICC cannot get wet

Contraindications

Absolute

• clinically in bacteremia or sepsis with and without neutropenia

Relative

• abnormal coagulation profile, prolonged bleeding time

• contrast allergy (can be performed without contrast administration)

Procedure

Technique

There are wide variations in technique. The following steps are an example of a technique:

• antibiotic prophylaxis is not recommended for routine use ^4,5

• preprocedure ultrasound can be performed to identify an appropriately-sized vein and ensure it is clot free

  • the most common vein is the right internal jugular vein

  • other veins include the left internal jugular vein, subclavian veins and inferior vena cava

  • vessel and port pocket should also not be ipsilateral with the breast cancer site or overlap with the proposed radiation therapy field

• the vein is punctured under ultrasound guidance, a guidewire is inserted and the proximal end is secured

  • the distal end of the guidewire is ideally placed in the inferior vena cava

• the port pocket is created under local anesthesia

  • the most common site for the pocket is at the pectoral region approximately 2.5 cm from the clavicle

• the catheter is inserted using a trocar subcutaneously from the pocket to the vein or vice versa

• the peel-away sheath is inserted to facilitate catheter insertion into the venous system

• catheter insertion is done during breath hold or inspiration and pinching of the peel-away sheath to minimize air embolism

• the catheter tip is adjusted to the superior cavoatrial junction

• the distal end of the catheter is attached to the port

• the port is anchored to the underlying muscle with sutures

• fluoroscopy is used to check for kinks and optimal positioning

• aspiration of blood is done to check function

• further contrast injection may be performed to reconfirm the tip position and function

• the port must be flushed with heparinised saline

• the pocket is sutured in two layers and sterile dressings applied

Complications

• infection: catheter- or wound-related (most common) ³

• tip migration

• deep vein thrombosis

• periprocedural

  • hemorrhage

  • arrhythmia

  • arterial puncture: less common with image guidance

• malposition: less common with image guidance

  • beware of anatomical variants such as a left SVC

• line fracture/embolization

• allergic reaction

• pinch off syndrome if a subclavian approach is used

• pneumothorax

• hemothorax

• infusothorax or chemothorax

History and etymology

The first port implantation performed in an angiography unit using interventional radiology techniques was performed in 1992 ².