Central Venous Catheters

OVERVIEW

• Central venous catheter (CVC) is a cannula placed in a central vein (e.g. subclavian, internal jugular or femoral)

USES/INDICATIONS

• Intravenous (IV) access (especially if difficult peripheral access)
• Central venous pressure (CVP) monitoring
• Central venous oxygen saturation (ScvO2) monitoring/sampling
• Infusions of irritant substances (e.g. vasoactive agents, chemotherapy or parenteral nutrition administration)
• Renal replacement therapy, plasmapheresis and apheresis (using a vascath)
• Transvenous pacing

Large bore peripheral IV lines, RICC lines, Swan sheaths or IO access are preferred for rapid fluid resuscitation.

CONTRAINDICATIONS

• obstructed vein (e.g. thrombus, or tumour)
• overlying skin infection, burn or other disease process
• hemorrhage from target vessel
• uncooperative patient

Femoral access can still be used in the following situations:

• coagulopathy
• respiratory failure
• raised intracranial pressure (ICP) (cannot tilt head down)

DESCRIPTION

• multi-lumen catheter
• brown lumen is the distal lumen (used for CVP monitoring)

METHOD OF INSERTION AND/OR USE

• aseptic technique
• ultrasound guided (if possible)
• head down (IJ, SC)
• head up (femoral)
• Seldinger technique
• ensure control of the guidewire at all times

Internal Jugular

• anatomy:
  • course:
    • origin from jugular foramen
    • joins subclavian vein behind sternal extremity of clavicle
  • medial relations: internal and common carotid arteries, 9th to 12th cranial nerves above common carotid artery and vagus
  • anterolateral relations: skin, superficial fascia, platysma, cervical fascia, sternomastoid, sternohyoid, omohyoid
  • posterior relations: transverse process of the cervical vertebrae, levator scapulae, scalenus medius and anterior, cervical plexus, phrenic nerve, thyrocervical trunk, vertebral vein, 1st part of subclavian artery
  • tributaries:
    • inferior petrosal sinus, facial, pharyngeal, lingual, superior thyroid, middle thyroid, occipital veins

• central approach:
  • insert 1cm above the apex of head of sternocleidomastoid and clavicle
  • advance 60 degrees to skin aiming towards ipsilateral nipple (blood should be obtained within 3cm)
  • lateral/posterior approach:
    • insert 2-3 finger breaths above clavicle along posterior border of SCM
    • direct needle towards jugular notch (blood should be aspirated within 5cm)
  • anterior approach:
    • identify the carotid and mid point of medial SCM border, aim toward ipsilateral nipple

Subclavian

• anatomy:
  • superior relations: midpoint of clavicle
  • anterior relations: skin, external jugular vein, clavicle
  • medial relations: fascia, trachea
  • posterior relations: subclavian artery, first rib, scalenus anterior, phrenic nerve and fascia over pleura

• approaches: supraclaviclar, infraclavicular and lateral

Femoral

• anatomy:
  • “NAVEL”: nerve – artery – vein – empty space – lymph node (lateral to medial)
  • boundaries of the femoral triangle are adductor longus and sartorius

• approach: slight external rotation of hip, palpate pulse, medial to arterial pulsation

Video demonstration of landmark approach to IJV CVC insertion

COMPLICATIONS

Immediate

• pneumothorax (highest for SCV)
• failure to locate vein
• accidental arterial puncture
• haemothorax
• haematoma
• arrhythmia
• thoracic duct injury
• guide wire embolus
• air embolus

Early

• haemopericardium and tamponade
• pneumothorax
• catheter blockage
• chylothorax
• catheter knots

Late

• infection (no difference in the rate of catheter-related bloodstream infections between the IJ, SC and Femoral sites -> 2.5 infections/ 1000 catheter days)
• catheter fracture
• vascular erosion
• vessel stenosis
• thrombosis
• osteomyelitis of clavicle

SITE COMPARISON

Choice of insertion site should be tailored to the needs and status of the patient. In general, the order of preference is subclavian (or axillary), internal jugular, then femoral. There are exceptions, for instance the subclavian route is usually best avoided in patients at risk of longterm dialysis (due to risk of vessel stenosis) or severe lung pathology (where the slightly higher risk of pneumothorax may be catastrophic).

The following table compares the common CVC insertion sites, which each having pros and cons:

	Internal jugular	Subclavian / axillary	Femoral
Access and insertion	Head-of-bed access   Tredelenberg position required   Difficult access during airway management   Collapsible vein if hypovolemia	Side-of-bed access   Trendelenberg position required   Accessible during airway management   Longer path from skin to vessel	Side-of-bed access   Trendelenburg position not required   Does not interfere with airway management   Most accessible site during CPR
Position of CVC tip	SVC (at level of carina)	SVC (at level of carina)	IVC (less likely to correlate with RAP)
Insertion success rate	Higher success rate with novice operator with ultrasound guidance	Decreased success rate with inexperience	Rapid access with high success rate
Risk of pneumothorax	Low (0.5%)	Highest (1.5%)	No risk
Bleeding and arterial injury	Compressible site   Risk of carotid artery puncture	Non compressible site (contraindicated if bleeding diathesis)	Compressible site   Highest rate of unintended arterial cannulation
Thrombosis and venous drainage	Potential to impede cerebral venous drainage and increase intracranial pressure	Lowest rates of thrombosis   Higher rate of stenosis (concern for long term dialysis)	Increased risk of iliofemoral thrombosis
Risk of infection	Moderate (3.6 per 1000 catheter days)	Lowest (1.5 per 1000 catheter days)	Highest (4.6 per 1000 catheter days)*
Comfort and mobility	Uncomfortable and not suited for prolonged access	Comfortable	Impedes patient mobility
Maintenance	Dressings more difficult to maintain (especially if patient has a tracheostomy)	Easy to maintain dressings	More difficult to keep site sterile
Other considerations	Risk of thoracic duct injury on left   Poor landmarks in patients with obesity/ neck oedema	Catheter malposition more common (especially right SCV)	Caution in patients with IVC filter   Delayed circulation of drugs during CPR

OTHER INFORMATION

Insertion length

Formulas for Catheter Insertion Length Based on Patient Height and Approach

Site	Formula (Height in cm)	In SVC (%)	In RA (%)
Right Subclavian (RSCV)	(Height/10) – 2 cm	96	4
Left Subclavian (LSCV)	(Height/10) + 2 cm	97	2
Right Internal jugular (RIJV)	Height/10	90	10
Left Internal jugular (LIJV)	(Height/10) + 4 cm	94	5

In practice, I tend to estimate the length based on patient height and body habitus and the CVC insertion location.

Confirmation of position

• ultrasound visualisation of needle insertion, guidewire placement and CVC
• pressure measurement
• assess for CVP trace
• inject agitated saline and observe rapid appearance of bubbles on bedside echo
• CXR

Handy tips

• Do not shave hair at insertion site unless it interferes with dressing adhesive, as it may increase the risk of infection from disruption of the epidermal barrier by skin lacerations.
• Draw up normal saline in a 10-mL syringe and lignocaine in a 5-mL syringe to ensure these two agents are not mixed up during the procedure.
• Use ECG monitoring during insertion of IJV and subclavian lines to detect transient dysrhythmia caused by guidewire irritation of the myocardium.
• CVC insertion is not necessary, or even optimal, for fluid resuscitation. A short wide-bore cannula is better.
• Ultrasound guidance is virtually the standard of care, where available and time permits. However the proceduralist must have adequate training.
• Abdominal compression or valsalva can increase the diameter of the internal jugular vein.
• Before inserting a CVL anticipate the future management of the patient, e.g. avoid IJV if PAC likely to be required, avoid SVC if likely to need fistula formation for hemodialysis, etc.
• Access to the SCV during CVC insertion may be facilitated by caudal traction (5 cm extension) on the ipsilateral upper limb, or by placing a roll under the ipsilateral shoulder.
• The chance of a complication escalates with repeated attempts, especially for SCV CVC insertion.
• Avoid placing a CVC in to shallow a depth — if in too the CVC can be pulled back, if too shallow CVC needs to be replaced by railroading a guidewire

References and Links

Journal articles

• Czepizak CA, O’Callaghan JM, Venus B. Evaluation of formulas for optimal positioning of central venous catheters. Chest. 1995 Jun;107(6):1662-4 PMID: 7781364.
• Kujur R, Rao MS, Mrinal M. How correct is the correct length for central venous catheter insertion. Indian J Crit Care Med. 2009 Jul-Sep;13(3):159-62. PMC2823099. (external validity is questionable!)
• Marik PE, Flemmer M, Harrison W. The risk of catheter-related bloodstream infection with femoral venous catheters as compared to subclavian and internal jugular venous catheters: a systematic review of the literature and meta-analysis. Crit Care Med. 2012 Aug;40(8):2479-85. PMID: 22809915.

FOAM and web resources

• Phillippe Le Favre — Central Venous Cather Insertion Guide (video guide, written guide, self test questions)