The brachiocephalic vein, also known as an innominate vein, is a vein that returns oxygen-depleted blood from the upper limbs, neck, and head to the heart.


There is a brachiocephalic vein on the left side of the neck and one on the right. The brachiocephalic vein on the left side of the neck is approximately 6 to 8 cm in length, while the brachiocephalic vein on the right is approximately two centimeters long.


The two brachiocephalic veins merge together with the azygous vein, which carries deoxygenated blood from the rib cage, to form the superior vena cava. The blood that flows into the heart from the superior vena cava is controlled by the contractions of the heart.


Abnormalities in the neck, such as compression of the trachea (windpipe) by the brachiocephalic vein on either or both sides of the neck, have been associated with apnea in infants. Apnea is a condition where breathing abnormally stops and starts during sleep. Magnetic resonance imaging is used to diagnose this condition. A tracheostomy is sometimes needed to correct the problem. A tracheostomy is surgical cut in the neck, usually made so that the patient can use a breathing tube.