Internal jugular vein

A major vein that drains blood from the head and neck regions and returns it to the heart.

The internal jugular vein is one of the primary veins responsible for draining deoxygenated blood from the brain, face, and neck. It runs down alongside the carotid arteries and receives blood from several important veins in the head. This vein is crucial for maintaining proper blood circulation and ensuring that waste products are efficiently carried away from the brain.

Terminologia Anatomica

vena jugularis interna

System

Circulatory system

Function

The internal jugular vein plays a pivotal role in the venous system by transporting blood back to the heart after it has delivered oxygen to the brain and other tissues. It works in concert with the external jugular vein, but unlike its counterpart, the internal jugular carries a larger volume of blood and is more directly involved with the brain's drainage system. Upon reaching the base of the neck, the internal jugular vein merges with the subclavian vein, forming the brachiocephalic vein, which then leads to the superior vena cava, ultimately returning blood to the right atrium of the heart. This process is essential in maintaining adequate cerebral perfusion, which is crucial for brain function and homeostasis. Additionally, as part of the body’s waste removal system, the internal jugular vein helps to regulate intracranial pressure, thereby playing an important role in overall brain health.

Location

The internal jugular vein is located within the neck and is positioned laterally to the carotid arteries. It originates at the base of the skull, where it collects blood from the brain via several tributaries. As it descends, it travels down the side of the neck, passing through the carotid sheath, which also houses the vagus nerve and other vital structures. This vein generally runs alongside the anterior border of the sternocleidomastoid muscle, which can be easily palpated when understanding its pathway. By the time it reaches the clavicle region, it angles medially to join the subclavian vein, thus forming the brachiocephalic vein. Its anatomical position is significant for both clinical assessments, such as central venous catheter placements, and for understanding various medical conditions affecting the head and neck.

Did You Know?

The internal jugular vein can vary in size and length between individuals, influencing surgical and medical procedures.
It is possible to see the internal jugular vein pulsating through the skin when a person is at rest, indicating normal venous pressure.
In emergency medical situations, the internal jugular vein is a common site for central venous catheter insertion due to its large diameter and proximity to the heart.