Overview
Definition:
An implantable port, often referred to as a chemo port or port-a-cath, is a small, self-sealing device surgically placed under the skin, typically in the upper chest, connected to a catheter that extends into a large vein, usually the superior vena cava
It provides long-term, reliable access for intravenous administration of medications, fluids, blood products, and for blood sampling.
Epidemiology:
Implantable ports are widely used in oncology for chemotherapy administration, impacting a significant proportion of cancer patients requiring long-term venous access
Their use extends to other specialties like nephrology, gastroenterology, and for long-term parenteral nutrition
Incidence varies based on disease prevalence requiring such access.
Clinical Significance:
Implantable ports significantly improve patient quality of life by minimizing repeated venipunctures, reducing the risk of phlebitis and infection associated with peripheral lines, and allowing for more comfortable and efficient administration of therapies
Proper insertion and management are crucial to prevent serious complications that can impact patient outcomes and healthcare costs.
Indications
Indications For Insertion:
Long-term chemotherapy administration
Frequent blood sampling
Administration of vesicant or irritant agents
Parenteral nutrition
Long-term antibiotic therapy
Apheresis procedures.
Contraindications:
Active systemic infection
Local skin infection at the insertion site
Patient refusal
Limited venous access due to previous interventions or anatomical abnormalities
Severe coagulopathy without correction.
Patient Selection:
Patients requiring venous access for more than 4-6 weeks
Patients with difficult peripheral venous access
Patients needing frequent blood draws
Patients receiving vesicant chemotherapy
Patients requiring long-term parenteral nutrition.
Preoperative Preparation
Informed Consent:
Detailed discussion of the procedure, risks (infection, bleeding, pneumothorax, thrombosis, device malfunction), benefits, alternatives, and post-operative care
Obtaining written informed consent is mandatory.
Patient Assessment:
Review of medical history, allergies, current medications (especially anticoagulants), and previous surgeries
Physical examination focusing on the intended insertion site and venous anatomy
Assessment of coagulation status.
Premedication:
Prophylactic antibiotics are often administered intravenously prior to insertion, typically a first-generation cephalosporin like cefazolin (1-2g IV).
Patient Positioning:
The patient is positioned supine with the arm on the side of insertion abducted 90 degrees and externally rotated
A small sandbag or roll can be placed under the ipsilateral shoulder to accentuate neck veins
Adequate analgesia is provided, often with local anesthesia and sometimes conscious sedation.
Procedure Steps
Technique Overview:
The procedure involves creating a subcutaneous pocket for the port reservoir and tunneling a catheter into a central vein.
Site Selection:
Typically the subclavian or internal jugular vein is accessed, with the port reservoir placed in the upper chest over the pectoralis major muscle
The contralateral side is preferred if a mastectomy or axillary node dissection has been performed on the side of insertion.
Venous Access:
Ultrasound guidance is highly recommended for optimal venous access
The vein is accessed using a needle and guidewire
A small incision is made over the vein to facilitate guidewire insertion.
Catheter Insertion:
A subcutaneous tunnel is created from the venous access site to the desired port pocket site
The catheter is advanced through the subcutaneous tunnel and into the central vein, with its tip ideally positioned at the cavoatrial junction
Proper tip placement is confirmed radiographically.
Port Placement:
A subcutaneous pocket is dissected over the pectoralis major muscle
The port reservoir is then placed into this pocket and secured
The catheter is connected to the port body, ensuring a secure connection.
Closure:
The skin incisions are closed in layers, and a sterile dressing is applied
The port should be flushed with heparinized saline to confirm patency and prevent clotting.
Postoperative Care
Wound Care:
Keep the insertion site clean and dry
Dressing changes as per hospital protocol
Monitor for signs of infection.
Pain Management:
Analgesics as needed
Local anesthetic infiltration at the site during closure provides significant post-operative pain relief.
Activity Restrictions:
Avoid strenuous activity involving the arm on the side of insertion for the first week to allow for secure healing of the subcutaneous pocket and venous access site.
Monitoring:
Regular assessment for signs of infection, thrombosis, catheter occlusion, or dislodgement
Patient education on port care and recognizing warning signs.
Flushing Protocol:
After each use, the port should be flushed with a minimum of 10-20 mL of saline followed by 5-10 mL of heparinized saline (e.g., 100 units/mL) to maintain patency and prevent clotting, especially when not in regular use.
Complications
Early Complications:
Bleeding and hematoma formation at the insertion site
Infection of the port pocket or catheter
Pneumothorax or hemothorax from attempted venous cannulation
Arterial puncture
Air embolism
Nerve injury.
Late Complications:
Catheter occlusion (fibrin sheath, thrombus, drug precipitate)
Catheter-related bloodstream infection (CRBSI)
Thrombosis of the central vein
Catheter migration or fracture
Port pocket infection/dehiscence
Skin erosion over the port
Allergic reaction to device components.
Management Of Complications:
Infection: Antibiotics, sometimes requiring port removal
Thrombosis: Anticoagulation, potential thrombolysis or thrombectomy
Occlusion: Saline or urokinase flush, or mechanical intervention
Removal is indicated for recurrent infections, significant thrombosis, or device malfunction.
Port Removal
Indications For Removal:
Completion of therapy
Persistent port infection or CRBSI
Symptomatic thrombosis
Catheter malfunction or occlusion not amenable to treatment
Patient preference.
Procedure For Removal:
Port removal is a minor surgical procedure performed under local anesthesia
An incision is made over the port reservoir, and the pocket is dissected
The catheter is then carefully withdrawn from the vein, and the subcutaneous tunnel is cleared of the catheter
Both incisions are closed.
Post Removal Care:
Similar to insertion site care, keeping the wound clean and dry
Monitoring for bleeding or infection
Resumption of normal activities as tolerated.
Key Points
Exam Focus:
Understand indications, contraindications, and common complications of implantable ports
Differentiate between early and late complications
Know the principles of port care and flushing protocols
Recognize imaging findings related to port placement and complications.
Clinical Pearls:
Always confirm venous patency and position with imaging post-insertion
Ultrasound guidance significantly reduces complications during venous access
Meticulous aseptic technique is paramount to prevent infection
Regular flushing with heparinized saline is critical for long-term patency.
Common Mistakes:
Failure to confirm tip placement radiographically
Inadequate flushing leading to occlusion
Over-aggressive manipulation of the catheter
Not considering port-related thrombosis as a cause of upper extremity swelling
Delayed recognition and management of port infections.