Healthcare and Medicine Reference
In-Depth Information
CHAPTER 11
Access: Central Venous
Ronan O'Leary 1 and Andrew Quinn 2
1 Yorkshire Deanery, York, UK
2 Department of Anaesthesia, Bradford Royal Infi rmary, Bradford, UK
Contraindications
Given the wide range of indications for central venous access it
is diffi cult to describe any absolute contraindications other than
patient refusal. Relative contraindications depend on the clinical
indication, the skill and experience of the operator, and where the
patient will be nursed after insertion. The most important relative
contraindications:
uncorrected coagulopathy
OVERVIEW
By the end of this chapter you should be able to:
explain both the benefi ts and risks of central venous access
understand the anatomy of the internal jugular, subclavian and
femoral veins
explain both anatomical landmark and ultrasound-guided
techniques for central line insertion
understand the potential complications of this invasive
thrombocytopenia
procedure.
skin infection over the site of access
obscure anatomical landmarks
haemo- or pneumothorax on the contralateral side
recent surgery to other structures nearby such as carotid
Introduction
endartectomy.
Rare contraindications include arteriovenous malformations,
renal cell tumour extension into the right atrium, and fungating
tricuspid valve vegetations.
Central venous access is a frequently performed invasive procedure
which carries a signifi cant risk of morbidity and even mortality.
It is usual for this procedure to be carried out in operating theatre
or high-dependency care areas, always using a fully aseptic tech-
nique. Ultrasound can be used to identify the vessels and to avoid
important nearby structures.
Central venous access refers to lines placed into the large veins of
the neck, chest, or groin. To measure central venous pressure, the
tip must lie within the thoracic cavity and preferably in the supe-
rior vena cava. As such, the femoral route is suboptimal for this
purpose. The device may be inserted directly into a central vein,
tunnelled subcutaneously and then inserted into a central vein or
inserted via a peripheral vein.
Anatomy
It is impossible to understate the importance of knowing the
anatomy relevant to central venous access. A good way to learn
these techniques is to position a colleague in the manner described
in these sections and to identify the landmarks, vessels and
pulsations.
Internal jugular vein (IJV)
The IJV runs from its origin at the jugular foramen to the
sternal margin of the clavicle. Here it terminates by joining the
subclavian vein (SCV) to form the brachiocephalic vein
(Figure 11.1).
The IJV is surrounded by the carotid sheath which also contains
the carotid artery, and the vagus nerve. When the vein forms it
initially lies very superfi cially in the anterior triangle of the neck
and overlies the internal carotid artery. As it descends it moves to
lie laterally to the artery.
Indications
Monitoring (these techniques are discussed in more detail in
Chapter 19).
Infusion of irritant drugs that may damage smaller veins.
Insertion of pacing wires.
Renal replacement therapy.
Emergency venous access.
Parenteral feeding.
Resuscitation of patients who are intravascularly depleted.
Subclavian vein (SCV)
The SCV is a continuation of the axillary vein. It begins at the
outer border of the fi rst rib and ends at the medial border of sca-
lenus anterior, where it joins the internal jugular vein to form the
brachiocephalic vein behind the sternoclavicular joint.
 
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