Central line placement is a procedure in which a thin, flexible catheter is inserted into a large vein, typically in the neck, chest, or groin, with the tip positioned near the heart. It gives medical teams direct access to the central bloodstream, which is essential when standard IVs in the arm or hand aren’t enough to deliver the fluids, medications, or monitoring a patient needs. Central lines are a routine part of critical care, and tens of thousands are placed in hospitals every day.
Why a Central Line Is Needed
A regular IV works well for simple tasks like delivering saline or antibiotics. But some situations demand a bigger, more reliable route into the bloodstream. Central lines are placed when patients need powerful medications that would damage smaller veins, when multiple incompatible drugs must run simultaneously, or when peripheral veins are simply too difficult to access.
The most common reasons include:
- Blood pressure support: Medications that raise dangerously low blood pressure (vasopressors) are too caustic for small arm veins and must go through a central line.
- Dialysis and blood filtering: Hemodialysis and similar therapies require high-flow access that only a large central vein can provide.
- Nutrition delivered by vein: Total parenteral nutrition, used when the gut can’t absorb food, is too concentrated for peripheral IVs.
- Chemotherapy: Many cancer drugs would scar or destroy smaller veins.
- Monitoring: Central lines can measure pressure inside the veins near the heart, helping guide fluid and medication decisions in critically ill patients.
- Failed or inadequate IVs: In emergencies, or when a patient’s veins are difficult to access, a central line provides reliable access fast.
- Mass blood transfusions: Trauma patients who need rapid, large-volume transfusions may require central access.
Where the Catheter Goes
Three veins are used most often, each with trade-offs depending on the clinical situation.
The internal jugular vein runs along the side of the neck, just beneath a muscle you can see when you turn your head. It’s the most commonly chosen site, partly because ultrasound gives a clear view of the vein and the nearby carotid artery. During placement, the bed is tilted so the head sits lower than the feet (a position called Trendelenburg), which enlarges the vein and makes it easier to access. The vein itself sits surprisingly close to the surface, often just 10 to 12 millimeters beneath the skin.
The subclavian vein passes just beneath the collarbone. This site is often preferred when the line needs to stay in for more than a few days, because it’s easier to keep clean and secure. The main risk is puncturing the top of the lung, which sits nearby.
The femoral vein runs through the groin. It’s the fastest to access in an emergency and carries no risk of lung injury, but the groin location makes infection more likely with prolonged use.
Regardless of which vein is used, the catheter tip ends up in the same place: the lower third of the superior vena cava, the large vein that empties into the heart’s right upper chamber. This position allows medications to mix quickly with a high volume of blood, reducing the risk of vein irritation.
How the Procedure Works
Central line placement uses a technique called the Seldinger method, which involves threading the catheter over a thin guidewire rather than pushing it directly into the vein. The process typically takes 15 to 30 minutes, though it can be faster in experienced hands or slower in difficult cases.
The skin is first cleaned with antiseptic and covered with sterile drapes. The provider numbs the area with a local anesthetic, usually injecting about 5 milliliters beneath the skin. You’ll feel a sting and some pressure during this step, but it significantly reduces pain for the rest of the procedure. Some patients also receive a mild sedative beforehand.
Once the area is numb, a needle is advanced into the vein while the provider watches on ultrasound. When blood flows back through the needle, confirming it’s in the vein, a flexible guidewire is threaded through the needle and into the vessel. The needle is then removed, leaving just the wire in place. A dilator (a firm, tapered tube) is slid over the wire to widen the opening in the skin and tissue, then removed. Finally, the catheter itself is threaded over the wire, the wire is pulled out, and the catheter is sutured to the skin and covered with a sterile dressing.
Most central line catheters have two or three separate channels (called lumens), each with its own port. This allows multiple medications to run at the same time without mixing.
Confirming Correct Placement
After a central line is placed in the neck or chest, a chest X-ray is taken before the line is used. The X-ray confirms that the catheter tip is sitting in the correct spot near the junction of the superior vena cava and the right atrium. It also checks for complications like a collapsed lung. Some newer technologies can verify tip position during the procedure itself, but a post-placement X-ray remains standard practice in most hospitals.
Risks and Complication Rates
Central line placement is generally safe, but it does carry real risks. A large meta-analysis pooling data from tens of thousands of catheters found the following complication rates per 1,000 lines placed:
- Arterial puncture: about 16 per 1,000 (the needle accidentally hits a nearby artery instead of the vein)
- Pneumothorax: about 4 per 1,000 (a small puncture in the lung, most relevant for neck and chest sites)
- Arterial cannulation: about 3 per 1,000 (the catheter is mistakenly placed into an artery, requiring removal)
Less common but serious complications include nerve injury, abnormal heart rhythms triggered by the guidewire touching the heart, and bleeding that requires intervention. These events are rare enough that pooled data is limited.
Ultrasound guidance has significantly improved safety. Compared to the older landmark technique (feeling for bones and muscles to estimate vein location), ultrasound-guided placement succeeds on the first needle pass far more often and requires fewer total attempts. One study of subclavian vein access found first-attempt success in 64 out of 75 patients with ultrasound versus just 30 out of 75 using landmarks. Ultrasound is now considered the standard of care for internal jugular and femoral vein access.
Infection Prevention
The most significant long-term risk of a central line is bloodstream infection, known clinically as CLABSI (central line-associated bloodstream infection). Bacteria can travel along the catheter and enter the blood, causing a potentially life-threatening infection. Hospitals follow strict prevention bundles to minimize this risk: hand hygiene before any contact with the line, full sterile barrier precautions during insertion, antiseptic skin preparation, careful site selection, and daily assessment of whether the line is still needed.
If you have a central line, you can reduce your own risk by avoiding touching the tubing or the site where it exits the skin. Ask your care team how long the line is expected to stay in place. The sooner it comes out, the lower the infection risk.
PICC Lines: A Related but Different Option
A PICC (peripherally inserted central catheter) is a type of central line that enters through a vein in the upper arm rather than the neck, chest, or groin. The catheter is much longer, traveling from the arm all the way to the same endpoint near the heart. PICCs are typically used for medium-term needs, such as weeks of IV antibiotics or chemotherapy, and can often be placed at the bedside by specially trained nurses.
Compared to standard central lines, PICCs tend to have lower rates of bacterial colonization even with longer use. However, they carry a higher risk of blood clots in the arm vein. The choice between a PICC and a standard central line depends on how long access is needed, what medications are being given, and the patient’s underlying health.