Atlas of Human Anatomy by Netter

[Plate 201, Bronchial Arteries and Veins]

page 107

page 108

Each lung is supplied by a pulmonary artery, which carries unoxygenated blood from the pulmonary trunk from the right ventricle of the heart.

Each pulmonary artery gives rise to lobar and segmental arteries.

Intrasegmental veins drain to intersegmental veins in the pulmonary septa, which run a separate course from the pulmonary and

segmental arteries and which drain to two pulmonary veins for each lung.

Pulmonary veins carry oxygenated blood to the left atrium of the heart.

Bronchial arteries from the thoracic aorta carry oxygenated blood to the tissue of the lungs, traveling along the posterior surface of the

bronchi.

The left bronchial arteries come from the thoracic aorta; the single right bronchial artery may also arise from the superior posterior

intercostal or a left superior bronchial artery.

The bronchial arteries anastomose with branches of the pulmonary arteries.

Pulmonary veins drain the blood to the lungs supplied by the bronchial veins and empty into the azygos and accessory hemiazygos veins.

The lungs have a rich, freely connecting network of lymphatic vessels.

Lymph from the lungs drains to

Pulmonary lymph nodes (along the lobar bronchi)

Bronchopulmonary lymph nodes (along the main stem bronchi)

Superior and inferior tracheobronchial lymph nodes (superior and inferior to the bifurcation of the trachea)

Innervation of the lungs

Innervation is via the pulmonary plexuses located anterior and posterior to the lung roots.

The plexuses contain postganglionic sympathetic fibers from the sympathetic trunks that innervate the smooth muscle of the bronchial tree,

pulmonary vessels, and glands of the bronchial tree.

Sympathetic fibers are bronchodilators, vasoconstrictors, and inhibit glandular secretion.

The plexuses contain preganglionic parasympathetic fibers from the vagus nerve (CN X), small parasympathetic ganglia, and

postganglionic parasympathetic nerves that innervate the smooth muscle of the bronchial tree, pulmonary vessels, and glands of the

bronchial tree.

Parasympathetic fibers are bronchoconstrictors, vasodilators, and secretomotor to the glands.

Visceral afferent fibers carry information involved in cough reflexes, stretch reception, blood pressure, chemoreception, and nociception