Nerve Supply to the Lung

• Receives afferent and efferent (parasympathetic preganglionic) fibers from the vagus nerve, joined by branches (sympathetic postganglionic fibers) from the sympathetic trunk and cardiac plexus.
• Is divided into the anterior pulmonary plexus , which lies in front of the root of the lung, and the posterior pulmonary plexus , which lies behind the root of the lung.
• Has branches that accompany the blood vessels and bronchi into the lung.
• Has sympathetic nerve fibers that dilate the lumina of the bronchi and constrict the pulmonary vessels, whereas parasympathetic fibers constrict the lumina , dilate the pulmonary vessels, and increase glandular secretion.

• Arises from the third through fifth cervical nerves (C3–C5) and lies in front of the anterior scalene muscle.
• Enters the thorax by passing deep to the subclavian vein and superficial to the subclavian arteries.
• Runs anterior to the root of the lung, whereas the vagus nerve runs posterior to the root of the lung.
• Is accompanied by the pericardiophrenic vessels of the internal thoracic vessels and descends between the mediastinal pleura and the pericardium.
• Innervates the fibrous pericardium, the mediastinal and diaphragmatic pleurae, and the diaphragm for motor and its central tendon for sensory.