part of lung parenchyma which is ventilated with the bronchus
of the 3rd branching and has its own branch of pulmonary
artery. That is why such parts are called bronchopulmonary
segments (segmenta bronchopulmonales). Bronchopulmonary
segment has the form of pyramid. The top of the segment is
directed to the hilum of the lung and its basis – to the external
surface of the lung. Each lung has 10 bronchopulmonary
segments:
The bronchopulmonary segments in the upper part of the
right lung are as follows:
1) apical segment (segmentum apicale [S
I
]);
2) posterior segment (segmentum posterius [S
II
]);
3) anterior segment (segmentum anterius [S
III
]).
In the middle lobe of the right lung:
4) lateral segment (segmentum laterale [S
IV
]);
5) mediastinal segment (segmentum mediale [S
V
]).
In the lower lobe:
6) superior segment (segmentum superius [S
VI
]);
7) mediastinal cardiac segment (segmentum basale mediale
(cardiacum) [S
VII
]);
8) main anterior segment (segmentum basale anterius [S
VIII
]);
9) main lateral segment (segmentum basale laterale [S
IX
]);
30
10) main posterior segment (segmentum basale posterius
[S
X
]).
In the upper lobe of the left lung:
1) – 2) apical-posterior
segment
(segmentum
apicoposterius [S
І
+
ІІ
]);
3) anterior segment (segmentum anterius [S
III
]);
4) upper lingular lobe (segmentum lingulare superius [S
IV
]);
5) lower lingular lobe (segmentum lingulare inferius [S
V
]).
In the lower lobe of the left lung:
6) upper segment (segmentum superius [S
VI
]);
7) mediastinal cardiac segment (segmentum basale mediale
(cardiacum) [C
VII
]);
8) main anterior segment (segmentum basale anterius [S
VIII
]);
9) main lateral segment (segmentum basale laterale [S
IX
]);
10) main posterior segment (segmentum basale posterius
[S
X
]).
The pulmonary tissue is supplied with blood mostly due to
2 – 3 bronchial arteries which depart from the thoracic part of
aorta and go along bronchi.
A. et vv. pulmonales are the vessels of lesser circulation and
have the function of gas exchange between air and blood. The
terminal branches of bronchial arteries of greater circulation
anastomose with pulmonary arteries. Bronchial veins
(vv. bronchiales) go into azygos vein (v. azygos) on the right,
and into hemiazygos vein on the left.
Deep and superior lymphatic vessels drain lymph from the
lungs. The superficial veins make surface vasculature which is
located in visceral pleura. Deep vasculature is located in
connective layers between the lung lobes.
Regional lymph nodes make the following groups:
1. Intrapulmonary lymph nodes (nodi lymphoidei
intrapulmonales) are located in the lung parenchyma,
31
mostly in places of bronchial branching.
2. Bronchopulmonary lymph nodes (nodi lymphoidei
bronchopulmonales) are located in the hilum. Their draining
lymph vessels go to tracheobronchial lymph nodes.
3. The superior and inferior tracheobronchial lymph nodes
(nodi lymphoidei tracheobronchiales superiores et inferiores)
are connected to trachea and superior and inferior primary
bronchi. Their draining lymph vessels go to the nodi
lymphoidei paratracheales.
4. Nodi lymphoidei paratracheales are located along the
trachea.
From the lung the lymph drains to the root of the lung and
before entering lymphatic duct passes through one of these
nodes. Most of the lymph is drained into the right lymphatic
duct (ductus lymphaticus dexter). From the inferior parts of
both lungs the lymph is drained by vessels which go through
lobes of pulmonary ligaments to the lymph nodes of posterior
mediastinum which are located along esophagus (nodi
lymphoidei juxtaoesophageales).
Lung innevation is provided by sympathetic and
parasympathic nerves. Sympathetic nerves cause bronchi
dilatation and vasoconstriction. Parasympathic nerves contract
bronchi, dilatate vessels, and increase secretion of mucous
glands.
The branches of vagus nerves and thoracic pulmonary
branches of sympathetic trunks form the pulmonary plexus
(plexus pulmonalis) in the hila. It is quite important
reflexogenic zone which should be blocked by novocaine
during operations.
Lung nerves are connected with heart nerves by means of
anastomoses.
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