Residency · Residency · Interventional Radiology

Venous Access: Central Venous Catheter Placement

Anatomy

Internal Jugular Vein (IJV)

The internal jugular vein forms at the jugular foramen as a continuation of the sigmoid sinus. It runs within the carotid sheath alongside the internal carotid artery (medially) and the vagus nerve (posteriorly). At the level of the thyroid cartilage, the IJV is typically anterolateral to the carotid artery. It joins the subclavian vein to form the brachiocephalic (innominate) vein behind the sternoclavicular joint. The right IJV is preferred for central access because it provides a straight course to the SVC and right atrium.

Subclavian Vein

The subclavian vein is the continuation of the axillary vein at the lateral border of the first rib. It courses anterior to the anterior scalene muscle and posterior to the clavicle, joining the IJV to form the brachiocephalic vein at the venous angle. The anterior scalene muscle separates it from the subclavian artery. The lung apex lies inferiorly, creating a risk of pneumothorax, and the vein is not compressible due to the surrounding bony structures, making hemorrhage difficult to control.

Femoral Vein

The femoral vein lies medial to the common femoral artery in the femoral triangle. It is the continuation of the popliteal vein and becomes the external iliac vein at the inguinal ligament. While it is easily accessible with ultrasound, it carries higher infection rates for indwelling catheters and is therefore reserved for emergent access or when upper extremity sites are unavailable.

Access Site Comparison

Indications

Central venous catheters are indicated for the administration of vasopressors, chemotherapy, total parenteral nutrition, or irritant medications. They are also used for hemodynamic monitoring via central venous pressure, in cases of inadequate peripheral venous access, for hemodialysis access (temporary or tunneled), for rapid volume resuscitation, and for transvenous pacing.

Contraindications

Relative Contraindications

Relative contraindications include coagulopathy (an INR greater than 2.0 or platelets below 50,000 for IJV or subclavian approaches, though this is less critical for femoral access given its compressibility), infection at the insertion site, anatomic distortion from prior surgery, radiation, or thrombosis, and contralateral pneumothorax (which precludes ipsilateral subclavian access).

Ultrasound-Guided Technique

Pre-Procedure

Before beginning, the operator should confirm the indication and review any imaging for venous patency. The patient is positioned in Trendelenburg for IJV and subclavian access to distend the veins and reduce the risk of air embolism. Sterile preparation and draping with full barrier precautions -- including cap, mask, sterile gown, sterile gloves, and a large sterile drape -- are essential for central line bundle compliance.

Internal Jugular Vein Access

A high-frequency linear probe in a sterile sheath is used to visualize the neck vasculature. In the short-axis view, the IJV appears lateral, thin-walled, and compressible, while the carotid artery is medial, pulsatile, and non-compressible. Patency is confirmed with compression and augmentation with Valsalva. The needle enters at the apex of the triangle formed by the two heads of the sternocleidomastoid muscle. A 21-gauge micropuncture needle is advanced under real-time ultrasound guidance at 30 to 45 degrees. Venous blood return is confirmed by its dark, non-pulsatile character. The operator then advances a 0.018-inch wire, confirms its position with ultrasound or fluoroscopy, and upsizes to the appropriate dilator and catheter.

Subclavian Vein Access

The infraclavicular approach involves inserting the needle 1 cm below the junction of the middle and medial thirds of the clavicle, aimed toward the sternal notch. Ultrasound is increasingly used with supraclavicular or infraclavicular approaches. The pneumothorax risk is higher than with IJV access (1-3% versus less than 0.1% with ultrasound-guided IJV). However, the subclavian site has a lower infection rate and is better suited for long-term catheters.

Femoral Vein Access

With the patient supine and the leg slightly abducted and externally rotated, ultrasound-guided access is obtained medial to the common femoral artery using the same micropuncture technique. This site carries higher infection and thrombosis rates, and long-term access through the femoral vein should be avoided.

Catheter Tip Positioning

The ideal tip position is at the cavoatrial junction (CAJ) or lower SVC. A tip that is too high risks vessel wall erosion and malfunction, while one that is too deep into the right atrium risks arrhythmia and cardiac perforation with tamponade. Tip position can be confirmed by several methods: fluoroscopy (the standard in IR, with the tip at or just above the carina on PA view), post-procedure chest radiograph, intracavitary ECG showing P-wave amplitude changes, or point-of-care ultrasound.

Complications

Immediate

Pneumothorax occurs primarily with the subclavian approach, and a post-procedure chest X-ray is obtained to evaluate for it. A small pneumothorax may be observed while a larger one requires a chest tube. Arterial puncture -- of the carotid with IJV access or the subclavian artery with subclavian access -- can usually be managed with compression if a small-gauge needle was used. Larger bore arterial cannulation may require surgical or endovascular repair.

Air embolism can occur from an open catheter hub or during wire exchanges and is prevented by Trendelenburg positioning, occluding the hub, and having the patient perform a Valsalva maneuver. Arrhythmia from a wire or catheter tip in the right ventricle is managed by withdrawing to the SVC or CAJ. Malposition into the contralateral brachiocephalic vein, azygos vein, or internal jugular vein should always be excluded with fluoroscopy.

Delayed

Central line-associated bloodstream infection (CLABSI) is minimized through bundle compliance, chlorhexidine dressings, and daily assessment of continued need. Catheter-related DVT, particularly with femoral and subclavian lines, is a recognized complication. Catheter malfunction from fibrin sheath formation or positional dysfunction can develop over time. Vessel stenosis, especially with subclavian catheters, is an important consideration -- subclavian access should be avoided in dialysis patients to preserve future arteriovenous fistula sites.

<image>Anatomical illustration of the right neck showing the internal jugular vein, common carotid artery, and vagus nerve within the carotid sheath. The sternocleidomastoid muscle is partially transparent to reveal the underlying structures. The ideal needle entry point at the apex of the triangle formed by the two heads of the SCM is marked. The subclavian vein is visible joining the IJV to form the brachiocephalic vein behind the sternoclavicular joint.</image>

<image>Ultrasound image illustration showing a short-axis (transverse) view of the right neck at the level of the thyroid cartilage. The internal jugular vein is shown as a larger, thin-walled, compressible oval structure anterolateral to the round, thick-walled, pulsatile common carotid artery. A micropuncture needle is shown entering from the lateral aspect under real-time guidance, with the needle tip within the IJV lumen.</image>

<image>Fluoroscopic illustration of proper central venous catheter tip positioning on a posteroanterior chest radiograph. The catheter enters via the right internal jugular vein, courses through the right brachiocephalic vein and SVC, with the tip positioned at the cavoatrial junction, approximately at the level of the carina. Key anatomical landmarks (carina, right mainstem bronchus, cardiac silhouette) are labeled.</image>

Clinical Pearls

Ultrasound guidance should always be used for central venous access. Evidence strongly supports reduced complications, and landmark-based technique is no longer an acceptable standard of care. The right IJV is the preferred site for most central venous access because of its straight course to the SVC.

Subclavian vein access should be avoided in patients with end-stage renal disease or an anticipated need for dialysis access in order to preserve upper extremity veins. Full barrier precautions and central line bundle compliance reduce CLABSI rates by up to 70 percent. Catheter tip position at the cavoatrial junction should be confirmed fluoroscopically before securing the catheter, and all lumens should be aspirated and flushed before use to confirm function and exclude air.

If an arterial puncture occurs with a large-bore needle or dilator, the device should not be removed -- vascular surgery or endovascular consultation should be obtained. Trendelenburg positioning is essential for IJV and subclavian access to prevent air embolism.

References

• Defined Practice Standards for Central Venous Access, SIR Practice Guidelines, 2020
• Defined by Defined Practice Standards from the CDC for Prevention of Intravascular Catheter-Related Infections, 2011 (updated 2017)
• Defined by Defined Practice Standards from Defined by Defined Practice Standards from AHRQ Central Line Insertion Practices (CLIP) Bundle
• Defined by Defined by the Defined by Defined by Defined by Defined by Defined by Defined by Defined by landmark meta-analysis by Defined by Defined by Defined by Hind et al., BMJ 2003 -- ultrasound-guided IJV access reduces complications
• Defined by Defined by Defined by Defined by the 2020 ASA Practice Guidelines for Central Venous Access

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