LUNG

Bronchial Tree The right main bronchus The right main bronchus Wider Wider More vertical More vertical

Bronchial Tree Right main bronchus Lobar bronchus Segmental bronchus trachea Left main bronchus Lobar bronchus

Bronchopulmonary Segment

Segmental bronchus and its accompanying pulmonary artery branch Segmental bronchus and its accompanying pulmonary artery branch 10 in each lung (some fuse in the left lobe) 10 in each lung (some fuse in the left lobe)

Bronchopulmonary Segment

Position

Midclavicular line Midaxillary line Scapular line Paravertebral line Inferior border of the lung Rib 6 Rib 8 Rib 10 T10 Inferior border of the pleura Rib 8 Rib 10 Rib 11 T12

Lung Base: the diaphragm Base: the diaphragm Apex: rib I, into the root of the neck Apex: rib I, into the root of the neck Surfaces: costal surface, mediastinal surface Surfaces: costal surface, mediastinal surface Borders: inferior border, anterior border, posterior border Borders: inferior border, anterior border, posterior border

Hilum and Root Root of the lung ( Anterior to posterior) Root of the lung ( Anterior to posterior) superior pulmonary vein superior pulmonary vein pulmonary artery pulmonary artery main bronchus main bronchus inferior pulmonary vein inferior pulmonary vein Pulmonary ligament Pulmonary ligament

Right Lung 2 fissures, 3 lobes 2 fissures, 3 lobes oblique fissure oblique fissure horizontal fissure horizontal fissure superior lobe superior lobe middle lobe middle lobe inferior lobe inferior lobe

Right Lung The root of the lung (superior to inferior) The root of the lung (superior to inferior) bronchus to superior lobe bronchus to superior lobe pulmonary artery pulmonary artery bronchus to middle and inferior lobes bronchus to middle and inferior lobes superior pulmonary vein superior pulmonary vein inferior pulmonary vein inferior pulmonary vein

Right Lung Structures adjacent to the medial surface of the right lung Structures adjacent to the medial surface of the right lung the heart the heart the inferior vena cava the inferior vena cava the superior vena cava the superior vena cava the azygos vein the azygos vein the esophagus the esophagus

Left Lung 1 fissure, 2 lobes 1 fissure, 2 lobes oblique fissure oblique fissure superior lobe superior lobe inferior lobe inferior lobe

Left Lung The root of the lung (superior to inferior) The root of the lung (superior to inferior) pulmonary artery pulmonary artery main bronchus main bronchus superior pulmonary vein superior pulmonary vein inferior pulmonary vein inferior pulmonary vein

Left Lung Structures adjacent to the medial surface of the left lung Structures adjacent to the medial surface of the left lung the heart the heart the aortic arch the aortic arch the thoracic aorta the thoracic aorta the esophagus the esophagus

Lung rightleft

Pulmonary Vessels Pulmonary arteries ← the pulmonary trunk Pulmonary arteries ← the pulmonary trunk Pulmonary veins → back into the left atrium Pulmonary veins → back into the left atrium

Bronchial Vessels Bronchial arteries and veins interconnect within the lung with braches of the pulmonary arteries and veins Bronchial arteries and veins interconnect within the lung with braches of the pulmonary arteries and veins “Nutritive” vascular system “Nutritive” vascular system

Bronchial Vessels Bronchial arteries ← thoracic aorta or one of its branches Bronchial arteries ← thoracic aorta or one of its branches on the posterior surfaces of the bronchi and ramify in the lungs to supply pulmonary tissues. on the posterior surfaces of the bronchi and ramify in the lungs to supply pulmonary tissues.

Bronchial Vessels Bronchial veins Pulmonary veins or left atrium Azygos veins or superior intercostal veins or hemiazygos veins

Innervation

Innervation The vagus nerves constrict the bronchioles The vagus nerves constrict the bronchioles The sympathetic system dilate the bronchioles The sympathetic system dilate the bronchioles

Lymphatic drainage tracheobronchial parasternal brachiocephalic tracheobronchial parasternal brachiocephalic nodes nodes nodes nodes nodes nodes right or left bronchomediastinal trunks deep veins at the base of the neck, or right lymphatic trunk or thoracic duct

The lungs The lung is covered, over most of its surface, by a thin and smooth membrane, the visceral pleura. On the medial surface of the lung, at the hilum (L., a little thing) this smooth membrane reflects away from the surface of the lung and folds back to line the internal surface of the cavity in which the lung is suspended. This latter layer is known as the parietal pleura and covers the inner surface of the chest wall, the superior surface of the diaphragm, and the lateral surface of the mediastinum. Specialized regions of the parietal pleural membrane are named for the structures they cover. The lung is covered, over most of its surface, by a thin and smooth membrane, the visceral pleura. On the medial surface of the lung, at the hilum (L., a little thing) this smooth membrane reflects away from the surface of the lung and folds back to line the internal surface of the cavity in which the lung is suspended. This latter layer is known as the parietal pleura and covers the inner surface of the chest wall, the superior surface of the diaphragm, and the lateral surface of the mediastinum. Specialized regions of the parietal pleural membrane are named for the structures they cover.

The mediastinal pleura covers the lateral surface of the mediastinum. The diaphragmatic pleura covers the superior surface of the diaphragm. The costal pleura lines the internal surface of the ribcage. The most superior portion of the pleural membrane, the cervical pleura, or dome of the pleura, extends 1 to 2 cm into the neck above the level of the clavicle and first rib. All of these portions of the parietal pleura are, of course, continuous with each other. The mediastinal pleura covers the lateral surface of the mediastinum. The diaphragmatic pleura covers the superior surface of the diaphragm. The costal pleura lines the internal surface of the ribcage. The most superior portion of the pleural membrane, the cervical pleura, or dome of the pleura, extends 1 to 2 cm into the neck above the level of the clavicle and first rib. All of these portions of the parietal pleura are, of course, continuous with each other. The visceral and parietal pleurae are continuous with each other at the hilum, where a slightly elongated "collar" of pleura forms. Encircled by this collar are the structures that connect the lung to the mediastinum: the pulmonary and bronchial vessels, the airways, nerves, lymphatics, and the connective tissue. The visceral and parietal pleurae are continuous with each other at the hilum, where a slightly elongated "collar" of pleura forms. Encircled by this collar are the structures that connect the lung to the mediastinum: the pulmonary and bronchial vessels, the airways, nerves, lymphatics, and the connective tissue.

A small inferior extension of this pleural collar is known as the pulmonary ligament, and, in the living, it may be palpated during surgery as a firm shelf of tissue on the medial surface of the lung. The pleural cavity is the potential space between the visceral and parietal pleurae. A small inferior extension of this pleural collar is known as the pulmonary ligament, and, in the living, it may be palpated during surgery as a firm shelf of tissue on the medial surface of the lung. The pleural cavity is the potential space between the visceral and parietal pleurae. Inferolaterally on each side of the chest, where the lateral edge of the diaphragm meets the chest wall, is the costodiaphragmatic (costophrenic) recess. This recess is very lucent (i.e., dark) on an x-ray when the lung expands fully to fill it; at expiration, however, the lung recedes upward and the diaphragm and chest wall move near to each other once again, and the lucency disappears. Inferolaterally on each side of the chest, where the lateral edge of the diaphragm meets the chest wall, is the costodiaphragmatic (costophrenic) recess. This recess is very lucent (i.e., dark) on an x-ray when the lung expands fully to fill it; at expiration, however, the lung recedes upward and the diaphragm and chest wall move near to each other once again, and the lucency disappears.

If, however, a patient has blood or inflammatory fluid in the pleural cavity, the fluid flows down into this recess, and in such a patient's x-ray at inspiration the angle is "blunted" by the accumulated fluid. There is another normally widened area of the pleural cavity anterior to the heart, on the left side, known as the costomediastinal recess. It becomes lucent at inspiration when the lingula of the left lung expands into it. If, however, a patient has blood or inflammatory fluid in the pleural cavity, the fluid flows down into this recess, and in such a patient's x-ray at inspiration the angle is "blunted" by the accumulated fluid. There is another normally widened area of the pleural cavity anterior to the heart, on the left side, known as the costomediastinal recess. It becomes lucent at inspiration when the lingula of the left lung expands into it.