The internal jugular vein (IJV) arises at the base of the skull, in the posterior compartment of the jugular foramen, as the continuation of the jugular bulb of the sigmoid sinus. At this point it receives the inferior petrosal sinus and passes down posteriorly and then laterally to the internal and later common carotid artery. In the triangular space between the clavicular and sternal heads of the sternomastoid it joins with the subclavian vein to form the innominate vein.

The most important superficial relationship of the IJV is the sternomastoid which is lateral to the vein in its upper part and covers it in the lower part (Figure 1, Figure 2). Other superficial relations include the posterior belly of the digastric and the superior belly of the omohyoid. The deep cervical lymph nodes lie along the course of the internal jugular vein.

The deep relations include the transverse processes of the cervical vertebrae (and therefore the vertebral artery), scalenus medius and anterior, the cervical plexus, phrenic nerve, sympathetic chain and the dome of the pleura. The internal and common carotid arteries accompany the internal jugular vein medially within the carotid sheath, and the vagus lies behind and between the vein and the arteries. These relationships are shown in a cross-sectional view in Figure 3. An ultrasonic image of the relationship with the carotid is shown in Figure 4. Recent ultrasonic studies suggest that the relationship between the internal jugular vein and the carotid artery is 'typical' in only about 70% of cases ¹ and that in about 15% of cases, the IJV passes in front of the artery.

In a clinical sense, the most crucial relationships are those with the carotid and vertebral arteries and, if a low approach to cannulation is used, the dome of the pleura. - Inadvertent arterial puncture (usually of the internal carotid artery) and, less commonly, pneumothorax are two important complications of the right internal jugular approach.

Unlike the subclavian vein, the internal jugular vein is a relatively unsupported structure and collapses easily if, for example, compressed by a palpating finger or by extreme rotation of the neck ².

The right internal jugular vein (IJV) is the site most commonly chosen for the insertion of a pulmonary artery catheter. In part, this is because most anaesthetists are right-handed and right-sided insertion is technically easier. However, it should also be remembered that on this side, the IJV leads straight into the superior vena cava, the pleural dome is lower and that the risk of thoracic duct injury is non-existent. It has also been recently demonstrated that the left IJV is significantly smaller than the right in about one third of the population ³.

1. Caridi JG, Hawkins IF Jr, Wiechmann BN, Pevarski DJ, Tonkin JC. Sonographic guidance when using the right internal jugular vein for central vein access. Am J Roentgenol 1998 Nov;171(5):1259-63

2. Armstrong PJ, Sutherland R, Scott DH. The effect of position and different manoeuvres on internal jugular vein diameter size. Acta Anaesthesiol Scand, 38:229-31, 1994 Apr

3. Lobato EB, Sulek CA Moody RL et al Cross-sectional area of the right and left internal jugular veins. J Cardiothorac Vasc Anesth 1999 Apr;13(2):136-138

Last edited on: 13/11/2000