Port (medicine)
Under the skin, the port has a septum (a silicone membrane) through which drugs can be injected and blood samples can be drawn many times, usually with less discomfort for the patient (and clinician) than a more typical "needle stick".
Brand names include Eco Port, Clip-a-Port, SmartPort, Microport, Bardport, PowerPort, Passport, Port-a-Cath, Infuse-a-Port, Medi-Port, and Bioflo.
Ports were previously adapted for use in hemodialysis patients, but were found to be associated with increased rate of infections and are no longer available in the US.
A port consists of a reservoir compartment (the portal) that has a silicone bubble for needle insertion (the septum), with an attached plastic tube (the catheter).
The septum is made of a special self-sealing silicone; it can be punctured hundreds of times before it weakens significantly.
[a] Due to its design, there is a very low infection risk, as the breach of skin integrity is never larger than the caliber of the needle.
[3] A port is most commonly inserted as an outpatient surgery procedure in a hospital or clinic by an interventional radiologist or surgeon, under moderate sedation.
Implantation is increasingly performed by interventional radiologists due to advancements in techniques and their facile use of imaging technologies.
If there is difficult puncture, micropuncture set can be used to puncuture the vein and later switch to a bigger access system.
Then, a 5 to 6 cm incision is made to create a subcutaneous tissue pouch for the placement of port access site.
A tunnel is made from the port access site until adjacent to the internal jugular neck wound.
After the tip of the port catheter is confirmed at the aortocaval junction, the peel-off sheath is taken-off by peeling away with two hands.
[5] A follow-up on a chest radiograph can immediately detect complications associated with the procedure such as pneumothorax, hemothorax and malpositions of the catheter.
The most common placement is on the upper right portion of the chest, with the catheter itself looping through the right jugular vein, and down towards the patient's heart.
Portals: Catheters: For applications such as CT scan, high pressure infusion allowing ports are needed.
The risk of puncture increases when the artery lies superficial to the vein and for those with short neck and obese people.
Puncture of the carotid artery is significantly more rare, since attempts to access the nearby jugular vein are increasingly done with ultrasound guidance.
The fracture can be due to "pinch-off syndrome" when the vein and the catheter is compressed when passes between the clavicle and first rib before turning 90 degrees into the superior vena cava.
Fractured catheter component can dislodge most commonly into pulmonary arteries (35%), right atrium (27%), right ventricle (22%), and superior vena cava and peripheral veins (15.4%).
[5] Attempts to gain access to the subclavian vein can injure the lung coverings, potentially causing a pneumothorax.
An alternative is the PICC line, despite drawbacks such as external entry point and limited lifespan of the device.
[13] In the 1984 cyberpunk novel Neuromancer, a minor character, Peter Riviera, has a kind of medical port placed in his arm to facilitate his recreational drug use.
[14] Niederhuber et al. first reported the use of totally implantable central venous port system (TICVPS) in 1982.
