Chapter 1: Basic Anatomy
You are attempting to place a central line in the left internal jugular vein. Which structure is most likely to lie between the common carotid artery and the vertebral artery?
(A) internal jugular vein
(C) transverse process of C6
The answer is E. The internal jugular vein (IJV) lies in the carotid sheath and is most often lateral and anterior to the carotid artery and vagus nerve (Figure 1-1). It originates at the jugular foramen of the skull and terminates behind the clavicle upon joining with the subclavian vein to form the brachiocephalic vein. The IJV overlies much of the carotid artery in a significant number of patients—advancement of the needle inadvertently thought the vein may result in arterial puncture, especially if the needle is directed with a medial angulation.
FIG. 1-1. Anatomy of the neck. Note the relative position of the carotid artery, the internal jugular vein, and the thoracic duct. (Reproduced with permission from Morton DA, Albertine K, Foreman KB: The Big Picture: Gross Anatomy, 1st Ed. New York, NY: McGraw Hill; 2011.)
Posterior to the carotid sheath and its contents lie the transverse processes, scalene muscles, nerve roots, and vertebral artery and vein. Vertebral artery puncture and cannulation resulting from excessively deep needle advancement has been reported during attempted IJV cannulation. This is also a potential risk during interscalene brachial plexus block, as the vertebral vessels lie close to the nerve roots.
The thoracic duct emerges from the thorax between the esophagus and the pleura. It forms an arch posterior to the carotid sheath and in front of the vertebral vessels before traveling inferiorly and opening into the angle of the junction of the internal jugular and subclavian veins. Needle injury to the thoracic duct is a rare but reported complication of left-sided central venous access (both IJ and subclavian veins), which may result in chylothorax or lymphocutaneous fistula.
Ref: Jacob S. Human Anatomy: A Clinically-Orientated Approach. 1st ed. London, UK: Churchill Livingstone; 2007.
Which of the following best describes Chassaignac’s tubercle?
(A) the anterior tubercle of C5 transverse process
(B) the posterior tubercle of C5 transverse process
(C) the anterior tubercle of C6 transverse process
(D) the posterior tubercle of C6 transverse process