Internal jugular vein
Encyclopedia
The two internal jugular veins collect the blood from the brain
, the superficial parts of the face
, and the neck
.
and the sigmoid sinus
join to form the internal jugular vein
. The internal jugular vein begins in the posterior compartment of the jugular foramen
, at the base of the skull
.
It is somewhat dilated at its origin, and this dilatation is called the superior bulb.
It also has a common trunk into which drains the anterior branch of the retromandibular vein, the facial vein, and the lingual vein.
It runs down the side of the neck in a vertical direction, being at one end lateral to the internal carotid artery
, and then lateral to the common carotid, and at the root of the neck, it unites with the subclavian vein
to form the brachiocephalic vein
(innominate vein); a little above its termination is a second dilatation, the inferior bulb.
Above, it lies upon the rectus capitis lateralis, behind the internal carotid artery and the nerves passing through the jugular foramen
; lower down, the vein and artery lie upon the same plane, the glossopharyngeal and hypoglossal nerves passing forward between them; the vagus descends between and behind the vein
and the artery
in the same sheath (the carotid sheath
), and the accessory
runs obliquely backward, superficial
or deep to the vein.
At the root of the neck, the right internal jugular vein is a little distance from the common carotid artery
, and crosses the first part of the subclavian artery
, while the left internal jugular vein usually overlaps the common carotid artery.
The left vein is generally smaller than the right, and each contains a pair of valves, which are placed about 2.5 cm above the termination of the vessel.
or cartilage
. This makes them susceptible to damage. Due to the large volumes of blood that flow though the jugular veins, damage to the jugulars can quickly cause significant blood loss, which can lead to hypovolæmic shock and then death if not treated.
It should also be noted that cuts or abrasions in the skin near the jugular vein will bleed longer and more profusely (i.e from chewing tobacco or shaving accidents). Since 95% of the body's blood passes through this vein, it takes on average about 30 minutes to fully stop a shaving abrasion on the face.
of the heart and the internal jugular, blood can flow back into the internal jugular when the pressure in the atrium is sufficiently high. This can be seen from the outside, and allows one to estimate the pressure in the atrium. The pulsation seen is called the jugular venous pressure
, or JVP. This is normally viewed with the patient at 45 degrees turning his/her head slightly away from the observer. The JVP can be raised in a number of conditions:
The JVP can also be artificially raised by applying pressure to the liver (the hepatojugular reflux). This method is used to locate the JVP and distinguish it from the carotid pulse. Unlike the carotid pulse, the JVP is impalpable.
. Such a line may be inserted for several reasons, such as to accurately measure the central venous pressure or to administer fluids when a line in a peripheral vein would be unsuitable (such as during resuscitation when peripheral veins are hard to locate).
Because the internal jugular rarely varies in its location, it is easier to find than other veins. However, sometimes when a line is inserted the jugular is missed and other structures such as the carotid artery
or the vagus nerve
(CN X) are punctured, causing damage to those structures.
Brain
The brain is the center of the nervous system in all vertebrate and most invertebrate animals—only a few primitive invertebrates such as sponges, jellyfish, sea squirts and starfishes do not have one. It is located in the head, usually close to primary sensory apparatus such as vision, hearing,...
, the superficial parts of the face
Face
The face is a central sense organ complex, for those animals that have one, normally on the ventral surface of the head, and can, depending on the definition in the human case, include the hair, forehead, eyebrow, eyelashes, eyes, nose, ears, cheeks, mouth, lips, philtrum, temple, teeth, skin, and...
, and the neck
Neck
The neck is the part of the body, on many terrestrial or secondarily aquatic vertebrates, that distinguishes the head from the torso or trunk. The adjective signifying "of the neck" is cervical .-Boner anatomy: The cervical spine:The cervical portion of the human spine comprises seven boney...
.
Path
On both sides and at the base of the brain, the inferior petrosal sinusInferior petrosal sinus
The inferior petrosal sinuses, within the human head, are beneath the brain and allow blood to drain from the center of the head.They drain on either side inferiorly from the cavernous sinus and join with the sigmoid sinus to form the internal jugular vein, which continues inferiorly to drain...
and the sigmoid sinus
Sigmoid sinus
The sigmoid sinuses , within the human head, are two areas beneath the brain which allow blood to drain inferiorly from the posterior center of the head. They drain from the transverse sinuses and converge with the inferior petrosal sinuses to form the internal jugular vein...
join to form the internal jugular vein
Internal jugular vein
The two internal jugular veins collect the blood from the brain, the superficial parts of the face, and the neck.-Path:On both sides and at the base of the brain, the inferior petrosal sinus and the sigmoid sinus join to form the internal jugular vein...
. The internal jugular vein begins in the posterior compartment of the jugular foramen
Jugular foramen
The jugular foramen is a large aperture in the base of the skull. It is located behind the carotid canal and is formed in front by the petrous portion of the temporal, and behind by the occipital; it is generally larger on the right than on the left side....
, at the base of the skull
Human skull
The human skull is a bony structure, skeleton, that is in the human head and which supports the structures of the face and forms a cavity for the brain.In humans, the adult skull is normally made up of 22 bones...
.
It is somewhat dilated at its origin, and this dilatation is called the superior bulb.
It also has a common trunk into which drains the anterior branch of the retromandibular vein, the facial vein, and the lingual vein.
It runs down the side of the neck in a vertical direction, being at one end lateral to the internal carotid artery
Internal carotid artery
In human anatomy, the internal carotid arteries are two major arteries, one on each side of the head and neck. They arise from the common carotid arteries where these bifurcate into the internal and external carotid artery, and they supply the brain....
, and then lateral to the common carotid, and at the root of the neck, it unites with the subclavian vein
Subclavian vein
The subclavian veins are two large veins, one on either side of the body. Their diameter is approximately that of the smallest finger.-Path:Each subclavian vein is a continuation of the axillary vein and runs from the outer border of the first rib to the medial border of anterior scalene muscle...
to form the brachiocephalic vein
Brachiocephalic vein
The left and right brachiocephalic veins in the upper chest are formed by the union of each corresponding internal jugular vein and subclavian vein...
(innominate vein); a little above its termination is a second dilatation, the inferior bulb.
Above, it lies upon the rectus capitis lateralis, behind the internal carotid artery and the nerves passing through the jugular foramen
Jugular foramen
The jugular foramen is a large aperture in the base of the skull. It is located behind the carotid canal and is formed in front by the petrous portion of the temporal, and behind by the occipital; it is generally larger on the right than on the left side....
; lower down, the vein and artery lie upon the same plane, the glossopharyngeal and hypoglossal nerves passing forward between them; the vagus descends between and behind the vein
Vein
In the circulatory system, veins are blood vessels that carry blood towards the heart. Most veins carry deoxygenated blood from the tissues back to the heart; exceptions are the pulmonary and umbilical veins, both of which carry oxygenated blood to the heart...
and the artery
Artery
Arteries are blood vessels that carry blood away from the heart. This blood is normally oxygenated, exceptions made for the pulmonary and umbilical arteries....
in the same sheath (the carotid sheath
Carotid sheath
The carotid sheath is an anatomical term for the fibrous connective tissue that surrounds the vascular compartment of the neck. It is part of the deep cervical fascia of the neck, below the superficial cervical fascia meaning the subcutaneous adipose tissue immediately beneath the skin.The deep...
), and the accessory
Accessory nerve
In anatomy, the accessory nerve is a nerve that controls specific muscles of the shoulder and neck. As part of it was formerly believed to originate in the brain, it is considered a cranial nerve...
runs obliquely backward, superficial
Superficial
Superficial may refer to:*Superficial , an album by Heidi Montag*"Superficial" *The Superficial, a website devoted to celebrity gossip...
or deep to the vein.
At the root of the neck, the right internal jugular vein is a little distance from the common carotid artery
Common carotid artery
In human anatomy, the common carotid artery is an artery that supplies the head and neck with oxygenated blood; it divides in the neck to form the external and internal carotid arteries. - Structure :...
, and crosses the first part of the subclavian artery
Subclavian artery
In human anatomy, the subclavian arteries are two major arteries of the upper thorax , below the clavicle . They receive blood from the top of the aorta...
, while the left internal jugular vein usually overlaps the common carotid artery.
The left vein is generally smaller than the right, and each contains a pair of valves, which are placed about 2.5 cm above the termination of the vessel.
Clinical relevance
The jugular veins are relatively superficial and not protected by tissues such as boneBone
Bones are rigid organs that constitute part of the endoskeleton of vertebrates. They support, and protect the various organs of the body, produce red and white blood cells and store minerals. Bone tissue is a type of dense connective tissue...
or cartilage
Cartilage
Cartilage is a flexible connective tissue found in many areas in the bodies of humans and other animals, including the joints between bones, the rib cage, the ear, the nose, the elbow, the knee, the ankle, the bronchial tubes and the intervertebral discs...
. This makes them susceptible to damage. Due to the large volumes of blood that flow though the jugular veins, damage to the jugulars can quickly cause significant blood loss, which can lead to hypovolæmic shock and then death if not treated.
It should also be noted that cuts or abrasions in the skin near the jugular vein will bleed longer and more profusely (i.e from chewing tobacco or shaving accidents). Since 95% of the body's blood passes through this vein, it takes on average about 30 minutes to fully stop a shaving abrasion on the face.
JVP
As there is one pair of valves between the right atriumRight atrium
The right atrium is one of four chambers in the hearts of mammals and archosaurs...
of the heart and the internal jugular, blood can flow back into the internal jugular when the pressure in the atrium is sufficiently high. This can be seen from the outside, and allows one to estimate the pressure in the atrium. The pulsation seen is called the jugular venous pressure
Jugular venous pressure
The jugular venous pressure is the indirectly observed pressure over the venous system...
, or JVP. This is normally viewed with the patient at 45 degrees turning his/her head slightly away from the observer. The JVP can be raised in a number of conditions:
- right ventricular failure (heart failure),
- tricuspid stenosis
- tricuspid regurgitation
- cardiac tamponadeCardiac tamponadeCardiac tamponade, also known as pericardial tamponade, is an emergency condition in which fluid accumulates in the pericardium ....
The JVP can also be artificially raised by applying pressure to the liver (the hepatojugular reflux). This method is used to locate the JVP and distinguish it from the carotid pulse. Unlike the carotid pulse, the JVP is impalpable.
Catheterization
As the internal jugular is large, central and relatively superficial, it is often used to place venous linesCentral venous catheter
In medicine, a central venous catheter is a catheter placed into a large vein in the neck , chest or groin...
. Such a line may be inserted for several reasons, such as to accurately measure the central venous pressure or to administer fluids when a line in a peripheral vein would be unsuitable (such as during resuscitation when peripheral veins are hard to locate).
Because the internal jugular rarely varies in its location, it is easier to find than other veins. However, sometimes when a line is inserted the jugular is missed and other structures such as the carotid artery
Carotid artery
Carotid artery can refer to:* Common carotid artery* External carotid artery* Internal carotid artery...
or the vagus nerve
Vagus nerve
The vagus nerve , also called pneumogastric nerve or cranial nerve X, is the tenth of twelve paired cranial nerves...
(CN X) are punctured, causing damage to those structures.