What are the differential diagnoses for a neck mass that develops after placement of an internal jugular (IJ) central venous catheter?

Differential Diagnosis: Neck Mass Post-IJ Catheter Insertion

The most critical immediate differential diagnoses to consider are hematoma from arterial or venous injury, catheter malposition with thrombosis, and infection/abscess, as these directly impact mortality and require urgent intervention. 1

Life-Threatening Complications (Evaluate First)

Hematoma from Vascular Injury

• Arterial puncture with hematoma formation is the most common mechanical complication of IJ catheterization, occurring in 1.8-6.2% of procedures, and can cause airway compromise if expanding 1, 2
• Look for: rapid onset (minutes to hours), firm/tense mass, ecchymosis, potential airway deviation, history of multiple puncture attempts during insertion 2
• Higher risk with: coagulopathy, thrombocytopenia, multiple insertion attempts, lack of ultrasound guidance 2, 3

Venous Thrombosis

• Internal jugular vein thrombosis presents as a painful, firm neck mass developing days to weeks post-insertion, with potential for pulmonary embolism 4
• Look for: unilateral neck swelling, pain, palpable cord-like structure along the vein, fever if septic thrombophlebitis 4
• Risk factors: prolonged catheterization, catheter malposition or migration, high approach to IJ (mid-neck exit site), left-sided placement 1, 4

Catheter Malposition/Migration

• Spontaneous catheter migration into the IJ vein can cause localized thrombosis and present as a neck mass 4
• Confirm with: chest X-ray showing catheter tip position change, ultrasound demonstrating catheter in IJ rather than SVC 4

Infectious Complications

Catheter-Related Infection/Abscess

• Local exit site infection or abscess formation is more common with IJ catheters than subclavian (higher local infection risk) 1, 5
• Look for: erythema, warmth, purulent drainage, fluctuance, fever, leukocytosis, tenderness at insertion site 1
• Timeline: typically develops after 48-72 hours, but can occur earlier with contamination 5
• High-risk scenarios: mid-neck exit site (high IJ approach), inadequate dressing care, immunocompromised patients 1

Mechanical Complications

Pneumothorax (Delayed Presentation)

• While typically immediate, tension pneumothorax can present with neck swelling due to subcutaneous emphysema tracking from chest 6
• Look for: crepitus on palpation, respiratory distress, decreased breath sounds, hyperresonance 6
• More common with subclavian approach but can occur with low IJ approaches 1, 6

Hemothorax

• Can present with neck swelling if blood tracks into soft tissues, though rare 1

Rare/Benign Considerations

IJV Phlebectasia (Pre-existing, Incidental)

• Fusiform dilation of the IJV that may become more apparent post-catheterization due to increased attention to the area 7
• Characteristics: soft, compressible, increases with Valsalva/coughing, reduces spontaneously, painless 7
• This is a benign finding but should not be assumed without imaging confirmation 7

Immediate Diagnostic Approach

Perform bedside ultrasound immediately to differentiate between hematoma, thrombosis, abscess, and vascular injury 1, 8:

• Assess for fluid collections (hematoma vs. abscess)
• Evaluate IJ vein patency and presence of thrombus
• Confirm catheter position
• Rule out arterial injury or pseudoaneurysm

Obtain chest X-ray to confirm catheter tip position and rule out pneumothorax/hemothorax 1

If infection suspected: blood cultures, local wound cultures, CBC with differential 1

If expanding hematoma with airway compromise: secure airway first, then imaging 1

Critical Pitfalls to Avoid

• Never assume a neck mass is benign without imaging—delayed recognition of expanding hematoma can cause airway loss 1, 2
• Do not attribute all post-catheter neck swelling to technique—spontaneous catheter migration can occur as a late complication 4
• High IJ approaches (mid-neck exit sites) have significantly higher infection and complication rates than low lateral approaches 1
• Left-sided IJ catheters have higher thrombosis rates than right-sided 1, 8
• Patients with coagulopathy or thrombocytopenia are at markedly increased risk for hematoma formation even with successful placement 2, 3