Indications, contraindications and complications of CVC insertion

Just because this material has never shown up in the past papers does not mean it can safely be neglected. Many questions approach this indirectly. When asked about the disadvantages to the use of any intravascular indwelling device, the CVC complications can be brought up. Never previously seen in the exams, the existence of this chapter was vindicated when Question 15 from the second paper of 2015 had asked about the potential complications of CVC insertion, as well as the various ways one can tell the difference between neck vessels on ultrasound.

Indications for use of the central line:

There are only a few strong reasons for the insertion of a central venous access device:

  • IV access
  • Infusion of irritant substances
  • CVP monitoring
  • Advanced haemodynamic monitoring (PICCO, PA catheter)
  • Central venous oxygenation monitoring

Extended indications also include:

  • Inadequate peripheral access
  • Extracorporeal therapies (ECMO, CRRT)
  • IVC filter placement
  • Venous stenting
  • Transvenous pacing
  • Catheter-guided thrombolysis

 Contraindications to central veno

Contraindication for central venous cannulation

  • Obstructed vein (eg. clot)
  • Stenosis of the vein
  • Raised ICP (IJ line)
  • Severe coagulopathy
  • Respiratory failure with high FiO2
  • Contaminated site
  • Traumatised site (eg. clavicle fracture and subclavian line)
  • Burned site
  • Uncooperative awake patient
  • No absolute contraindications

Complications of central venous cannulation

This was asked about specifically in Question 15 from the second paper of 2015. The college only felt this issue merits 30% of the total question marks (the rest went into the question about using ultrasound to distinguish the carotid artery from the IJ vein)

  • Immediate
    • Failure of procedure
    • Pneumothorax
    • Haemothorax
    • Retroperitoneal haematoma
    • Arterial puncture
    • Local haematoma
    • Guidewire-induced arrhythmia
    • Thoracic duct injury
    • Guide wire embolism
    • Air embolism
  • Early
    • catheter blockage
    • chylothorax
    • catheter knots
  • Late
    • Infection : 2.5 infections/ 1000 catheter days
    • catheter fracture
    • vascular erosion
    • vessel stenosis
    • thrombosis
    • osteomyelitis of clavicle (subclavian access)

Ultrasonographic features which distinguish the internal jugular vein from the carotid artery

Question 15 from the second paper of 2015 asked for these features. For most of us, the two vessels are fairly easy to tell apart, but... if one were asked to articulate exactly how they differ, one might come to trouble. "Squishy" and "roundly pulsatey" are probably inappropriately loose terms to use in this context. Instead, please find the table below:

Ultrasonographic features
of the Internal Jugular Vein and the Carotid Artery
Features Internal Jugular Vein Carotid Artery
Shape Elliptical Circular
Size Larger Smaller
Wall thickness Thin Thick
Pulsatility Occasionally, might pulsate (eg. in severe TR) Always (should be ) pulsatile
Compressibility Compressible Non-compressible
Response to Valsalva Increases in diameter Remains unchanged with Valsalva
Colour Dopper May demonstrate pulsatile blood flow Should demonstrate pulsatile blood flow
Flow direction Flow should be laminar and present during both systole and diastole Flow should be laminar and present only during systole
Nyquist scale Low scale required (i.e. low velocity flow) High scale required (or, aliasing occurs)

This table comes in part from the college answer, and in part from Vascular ultrasound of the neck: an interpretive atlas.


Williams, William M. Vascular ultrasound of the neck: an interpretive atlas. Lippincott Williams & Wilkins, 2001.