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Central venous catheter - use
Type of catheter
 Single double or triple lumen.
 Sheaths for insertion of pulmonary artery catheter or pacing
wire
 Tunnelled catheter for long term use.
 Triple lumen catheters allow multiple infusions given
separately + continuous pressure monitoring. Minimizes risk
of accidental bolus
 12Fr
double lumen catheters used for venovenous
dialysis/filtration.
 Common routes are internal Jugular, subclavian and femoral.
 Long catheters can be inserted via medical brachial or axillary
veins though are generally not recommended due to the risk
of thrombosis.
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Uses
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Invasive haemodynamic monitoring.
Infusion of drugs liable to cause peripheral phlebitis or
tissue necrosis if tissue extravasation occurs (e.g. TPN,
dopamine, amiodarone).
Rapid volume infusion, n.b. the rate of flow is inversely
proportional to the length of the cannula.
Access, e.g. for pacing wire insertion.
Emergency access when peripheral circulation is ‘shout
down’.
Renal replacement therapy, plasmapheresis, exchange
transfusion.
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Contraindications / cautions
Coagulopathy
 Undrained pneumothorax on contralateral side
 Agitated, restless patient.
Complications
 Arterial puncture
 Haemorrhage
 Arrhythmias.
 Infection (Usually skin, occasionally sepsis or endocarditis).
 Pneumothorax.
 Air embolism, venous thrombosis, haemothorax, chylothorax (all
rare).
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Central venous pressure measurement
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Use of an electronic pressure transducer is preferable to
manometry which incorporates a three way tap, a fluid
reservoir bag and a fluid filled vertical column, the height
of which corresponds to CVP.
The pressure transducer should be placed and ‘zeroed’
at the level of the left atrium (approximately mid-axillary
line) rather than the sternum which is more affected by
patient position (supine/semi-erect/prone).
Venous pulsation and some respiratory swing should be
seen in the trace but not a RV pressure waveform (i.e.
catheter inserted too far).
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Troubleshooting
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Excessive bleeding at the insertion site is usually
controlled by direct compression.
If not controlled, correct any coagulopathy, If postthrombolysis, consider tranexamic acid.
The incidence of local infection (usually Staph.
Epidermidis or Staph. Aureus) rises > 5 days.
Routine change of catheter at 5 days is not necessary
though change over a wire may be sufficient if patient
develops and unexplained pyrexia or neutrophilia.
However, removal + change of site is needed if site is
cellulitic or blood cultures taken through the catheter are
psoitive.
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Central venous catheter - insertion
Landmarks
Various landmarks have been described. For example :
 Internal jugular : Halfway between mastoid process and sternal
notch, lateral to carotid pulsation and medial to medial border of
sternocleidomastoid. Aim toward ipsilateral nipple, advancing under
body of sternocleidomastoid until vein entered.
 Subclavian : 3cm below junction of lateral third and medial two
thirds of clavicle. Turn head to contralateral side. Aim for point
between jaw and contralateral shoulder tip. Advance needle
subcutaneously to hit clavicle. Scrape needle around clavicle and
advance further until vein entered.
 Formal : Locate femoral artery in groin. Insert needle 3 cm medially
and angled rostrally. Advance until vein entered.
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Insertion technique
The Seldinger technique (described below is safer than
the “catheter-over-needle” technique and should
generally be used in ICU patients.
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Use aseptic technique troughout. Clean area with
antiseptic and surround with sterile drapes.
Anaesthetise local area with 1% lignocaine. Flush
lumen(s) of catheter with saline.
Use metal needle to locate central vein.
Pass wire (with ‘J’ or floppy end leading) through
needle into vein. Only minimal resistance at most
should be felt. If not remove wire and confirm needle
tip is till locate within vein lumen. Monitor for
arrhythmias. If these occure, wire is probably at
tricuspid valve. Usually responds to pulling wire back a
few cm.
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Remove needle leaving wire extruding from skin puncture
site.
Depending on size/type of catheter to be inserted, a rigid
dilator (+ preceded by a scalpel incision to enlarge puncture
site) may be passed over the wire to form a track through
the subcutaneous tissues to the vein. Remove dilator.
Thread catheter over wire. Ensure end of wire extrudes
from catheter to prevent accidental loss of wire in vein.
Insert catheter into vein to depth of 15-20cm. Remove wire.
Check for flashback of blood down each lumen and
respiratory swing, then flush with saline.
Suture catheter to skin. Clean and dry area. Cover with
sterile transparent semi-permeable dressing.
A chest X ray is usually performed to very correct position
of tip (junction of superior vena cava & right atrium ) and to
exclude a pneumothorax. Unless in an emergency situation,
a satisfactory position should generally be confirmed before
use of the catheter.
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