PICC Line vs Central Line
PICC line and central line are often mentioned in radiology reports. These medical devices are important in gaining central venous access for administering medications, nutrition and other uses. This article will discuss the difference between central lines and PICC lines.
What Is a PICC Line?
A PICC line is a long, thin catheter inserted into a vein in the upper arm, usually the basilic, brachial, or cephalic vein. The tip extends into a large central vein near the heart, typically the superior vena cava.
PICC lines are used for long-term IV antibiotics, chemotherapy, total parenteral nutrition, and medication administration.
PICC Line on Chest X-ray and CT Scans
Radiologists confirm placement using a chest X-ray or sometimes a CT scan. The catheter appears as a thin, radiopaque line extending from the arm to the superior vena cava.
PICC Line Malposition and Complications on Imaging
A misplaced or kinked PICC line can cause complications. Radiologists check for:
- Malposition – The tip in the wrong vessel, such as the axillary vein instead of the superior vena cava
- Looping or kinking – Twisting inside the vein, potentially obstructing flow
- Thrombosis – Blood clots visible as a lack of blood flow on ultrasound
- Infection signs – Swelling or fluid collections near the insertion site
What Is a Central Line?
A central venous catheter, or central line, is inserted into large central veins. Unlike PICC lines, which are placed in the arm, central lines are inserted into the internal jugular vein in the neck, subclavian vein in the chest, or femoral vein in the groin.
Central lines are used for emergency medication, fluid resuscitation, hemodynamic monitoring, and dialysis when a hemodialysis catheter is required.
Central Line on Chest X-ray and CT Scans
A central line appears as a radiopaque tube leading from the insertion site to a large central vein, usually ending near the right atrium or superior vena cava.
Radiologists evaluate:
- Correct positioning – The tip should be at or just above the right atrium
- Pneumothorax – A collapsed lung due to accidental puncture, visible on X-ray
- Venous placement – A misplaced line in an artery, such as the carotid instead of the jugular vein
- Clot formation – Vessel narrowing or occlusion due to thrombosis
Key Differences Between PICC Line and Central Line on Imaging
PICC lines are inserted in the upper arm, while central lines are placed in the neck, chest, or groin.
Central lines have a higher risk of pneumothorax due to insertion near the lungs. PICC lines avoid this risk since they are placed in the arm.
PICC lines are designed for long-term use, lasting weeks to months. Central lines are used for short-term or critical care but can also be placed for extended use if tunneled or ported.
Common Imaging Findings and What They Mean
PICC Line Tip High
A PICC line tip is too high when it does not reach the cavoatrial junction. This may reduce effectiveness and require repositioning.
Central Line Malposition
A malpositioned central line is either in the wrong vessel or not deep enough. A misplaced line in an artery requires immediate correction.
No Pneumothorax
Since central line insertion risks lung puncture, radiologists check for pneumothorax and document whether it is present or absent.
Catheter-Related Thrombosis
A blood clot around a PICC or central line appears on ultrasound or CT as vessel narrowing or blockage. This may require line removal and anticoagulation therapy.
Radiologist’s Perspective on PICC and Central Lines
In my practice, I frequently assess PICC and central line placements in hospitalized patients.
One common finding is suboptimal catheter positioning. Catheter tip displacement can affect medication delivery. Imaging like chest X-rays are used to confirm the position of the catheter tip.
Another common issue is PICC line migration, where the catheter moves proximally back up the arm over time. This can lead to ineffective treatment and requires repositioning. Patients receiving long-term intravenous therapy should have periodic imaging to check line position.
Conclusion
PICC lines and central lines play an important role in IV therapy and critical care. They differ in insertion site, duration of use, and imaging appearance. Radiologists confirm placement and identify complications like malposition, thrombosis, or pneumothorax. If a radiology report mentions a PICC line or central line, it usually refers to the position of the catheter and any complications. Correct placement and identification of complications is important for patient care.
References
- https://www.ncbi.nlm.nih.gov/books/NBK459338/
- https://cancer.ca/en/treatments/tests-and-procedures/central-venous-catheter
- https://my.clevelandclinic.org/health/treatments/23927-central-venous-catheter