What is the ideal position for central line placement in children?

Central Line Tip Position in Children

The central venous catheter tip should be positioned outside the pericardial sac to prevent life-threatening cardiac tamponade, which requires specific anatomic positioning based on the child's size and the insertion site used. 1

Optimal Tip Position by Insertion Site

For Upper Body Access (Jugular/Subclavian)

In small infants (body length 47-57 cm): Position the catheter tip at least 0.5 cm above the carina on chest X-ray to ensure it lies outside the pericardial sac. 1

In larger infants (body length 58-108 cm): Position the catheter tip at least 1.0 cm above the carina on chest X-ray. 1

In children beyond infancy: The carina serves as a reliable landmark, with the tip positioned above the carina to ensure superior vena cava placement outside the pericardial boundaries. 1, 2

• The carina is consistently located 0.5 cm above the pericardial reflection in small children, making it a safe radiographic marker. 2
• Positioning above the carina places the tip in the superior vena cava, outside the pericardial sac. 1

For Femoral Access

Position the catheter tip above the renal veins (at or above the first lumbar vertebra) for long-term use. 1

Critical Safety Considerations

Why This Positioning Matters for Mortality Prevention

Cardiac tamponade risk: Catheter tips positioned within the pericardial sac can erode through the vessel wall, causing pericardial effusion and tamponade—a life-threatening complication. 1

• In preterm neonates, tamponade incidence reaches 1.8% even with modern polyurethane catheters. 1
• All pediatric tamponade cases from central lines occurred in newborns, with an incidence of 1.3%. 1

Thrombosis risk: Positioning the tip too peripherally (away from the right atrium) increases symptomatic venous thrombosis risk in adults, though pediatric data are limited. 1

Verification Requirements

Mandatory chest X-ray confirmation is required when:

• The tip position was not verified during the procedure. 1
• A blind subclavian approach was used. 1
• Any technique carrying pleuropulmonary injury risk was employed. 1

Intraoperative confirmation is strongly preferred, especially with infraclavicular subclavian approaches, to ensure accurate placement before use. 1, 3

Insertion Site Selection for Morbidity Reduction

Internal Jugular Vein (Preferred in Many Situations)

• Lower pneumothorax risk compared to subclavian access. 1
• Easily compressible if bleeding occurs during insertion. 1
• Lower thromboembolism risk compared to femoral and subclavian sites in pediatric cohort studies. 1

Subclavian Vein

• Higher hemothorax risk compared to jugular access. 1
• Acceptable for long-term use when appropriate insertion conditions exist. 1

Femoral Vein (Use with Caution)

• No increased infection risk in large pediatric studies, contrary to adult data. 1
• Higher thromboembolism risk compared to jugular access. 1
• Relatively contraindicated for parenteral nutrition in adults due to infection and thrombosis concerns, though pediatric data show no infection increase. 1

Common Pitfalls to Avoid

Never position the tip within the right atrium in neonates and small infants—this dramatically increases tamponade risk, particularly in the most vulnerable population. 1

Do not use the carina as a landmark in newborns—the pericardial reflection can extend 4 mm above to 5 mm below the carina in this age group, making it unreliable. 1

Avoid routine catheter repositioning—if the catheter is correctly positioned outside the pericardial sac, repositioning increases infection risk without benefit. 1, 3

Do not rely on clinical estimation alone—use height-based formulas or anatomic landmarks to predict insertion depth, as incorrect positioning can remain undetected for hours until the first chest X-ray. 4, 5

Practical Insertion Depth Guidelines

For right internal jugular or subclavian access:

• Patients ≤100 cm height: Insert (height in cm ÷ 10) - 1 cm. 4
• Patients >100 cm height: Insert (height in cm ÷ 10) - 2 cm. 4

For infants <5 kg via right subclavian:

• 2.0-3.0 kg: Insert 40-45 mm depth. 5
• 3.0-3.9 kg: Insert 45-50 mm depth. 5
• ≥4.0 kg: Insert 50-55 mm depth. 5

Alternative landmark for right internal jugular: Insert to a depth of (distance from skin puncture to right third intercostal space) - 1 cm, which positions the tip above the right atrium in 98.8% of children. 6

Technique Recommendations

Use ultrasound guidance for all central line insertions to reduce complications and improve success rates. 1, 3, 7

Use percutaneous, ultrasound-guided insertion rather than surgical cutdown—equally effective with fewer complications. 1

Reposition the catheter whenever necessary if post-insertion imaging shows the tip within the pericardial sac, despite the general recommendation against routine repositioning. 1