What are the risks of placing a central line on the left side?

Problems with Left-Sided Central Line Placement

Left-sided central venous access should be avoided when possible due to increased risk of thrombotic complications compared to right-sided placement. 1

Primary Concern: Increased Thrombosis Risk

The main problem with left-sided central line placement is the higher incidence of catheter-related venous thrombosis compared to right-sided access. 1 This occurs because:

• The left-sided approach creates a longer, more angulated catheter course to reach the superior vena cava-right atrium junction 2
• The anatomical path from the left internal jugular or subclavian vein requires the catheter to traverse a less direct route, increasing vessel wall trauma 1
• Right-sided access provides a straighter, more direct course to the SVC, resulting in easier catheter positioning and fewer complications 2

Evidence Strength and Guideline Recommendations

While the 2009 ESPEN guidelines noted that "some reports suggest that central venous catheters positioned on the left side may be associated with a higher risk of thrombosis," they stated there was "not enough evidence to give recommendations" at that time. 1 However, more recent 2021 and 2023 ESPEN guidelines have strengthened this recommendation, explicitly stating that right-sided access is preferable to left-sided approach with respect to risk for thrombotic complications. 1

Additional Left-Sided Complications

Beyond thrombosis, left-sided placement carries these specific risks:

Thoracic Duct Injury

• The thoracic duct terminates in the left neck at the jugulo-subclavian junction in 75-92% of cases 3
• Injury during left internal jugular or subclavian line placement can cause chylothorax, a serious complication requiring conservative management (successful in 20-80% of cases) or surgical/interventional treatment 4, 3
• This anatomical structure is absent on the right side, making right-sided access safer in this regard 3

Technical Considerations

• Tip malposition is more common with left-sided catheters due to the angulated course 1
• Higher risk of catheter dysfunction and potential for embolization during insertion 2

Clinical Algorithm for Site Selection

For all central line placements requiring upper body access:

1. First choice: Right internal jugular vein with ultrasound guidance 1

   • Provides optimal straight path to SVC-right atrial junction
   • Lowest thrombosis risk
   • Avoids thoracic duct

2. Second choice: Right subclavian vein (avoid in advanced kidney disease/hemodialysis patients) 5

   • Still maintains right-sided advantage
   • Higher pneumothorax risk than internal jugular

3. Consider left-sided access only when:

   • Right-sided vessels are thrombosed or stenotic 5, 2
   • Previous right-sided infection or trauma 5, 2
   • Right-sided pacemaker/ICD present 2
   • Anatomical abnormalities prevent right access 5, 2

Critical Pitfall to Avoid

Do not default to left-sided placement simply based on operator handedness or convenience. The increased thrombosis risk with left-sided catheters directly impacts patient morbidity through catheter dysfunction, need for anticoagulation, and potential line loss. 1 Always attempt right-sided access first unless specific contraindications exist. 1