2. Objectives
• Review of chest cavity, mediastinum, pleura, trachea, bronchi
• Review lung fissures and lobes
• Understand the bronchopulmonary segments
• Relate the discussion to the clinic
2Mudoogo Edgar
3. Chest cavity
• bounded by the chest wall and below
by the diaphragm
• extends upward into the root of the
neck about one fingerbreadth above
the clavicle on each side
3Mudoogo Edgar
4. Mediastinum
• though ,thick, movable partition
• Divided by an imaginary line into 2 parts
Structures in superior mediastinum A-P
• Thymus, large veins, large arteries, trachea, esophagus and thoracic
duct, and sympathetic trunks.
Structures in inferior mediastinum A-P
• Thymus, heart within the pericardium with the
phrenic nerves on each side, esophagus and thoracic
duct, descending aorta, sympathetic trunks
4Mudoogo Edgar
8. Trachea
• mobile cartilaginous and membranous tube
• begins in the neck as a continuation of the larynx
• descends in the midline of the neck.
• trachea ends below at the carina by dividing into right and left principal bronchi at the level of the
sternal angle
• During expiration, the bifurcation rises by about one vertebral level, and during deep inspiration may
be lowered as far as the T6
• is about 11.25 cm long , 2.5 cm in diameter
• kept patent by U-shaped bars (rings) of hyaline cartilage
• posterior free ends of the cartilage are connected by smooth muscle, the trachealis muscle.
8Mudoogo Edgar
9. Anteriorly
• The sternum
• the thymus
• the left brachiocephalic vein
• origins of the brachiocephalic left common
carotid arteries,
• arch of the aorta
Posteriorly
• The esophagus
• left recurrent
laryngeal nerve
Right side
• azygos vein
• right vagus nerve
• the pleura
Left side
• arch of the aorta
• left common Carotid
• left subclavian arteries
• left vagus
• left phrenic nerves
• the pleura
9Mudoogo Edgar
11. Bronchi
• right and left principal bronchi
• The right principal(main) bronchus is wider,
Right principal bronchus
• shorter, and more vertical than the left ,about 2.5 cm long.
• Before entering the hilum of the right lung off the superior lobar bronchus.
• On entering the hilum, it divides into a middle and an inferior lobar bronchus.
11Mudoogo Edgar
12. Left main bronchi
• is narrower,
• longer,
• more horizontal than the right
• 5 cm long.
• It passes to the left below the arch of the aorta in front of the esophagus.
• On entering the hilum of L lung, the principal bronchus divides into
superior and inferior lobar bronchus.
12Mudoogo Edgar
14. LUNGS
• Are soft, spongy and elastic
• would immediately shrink to one third or less in volume if thoracic cavity was
opened
• Pink in the child , become dark and mottled .
Why??????
• because of the inhalation of dust particles that become trapped in the phagocytes
of lungs
• Each is conical, covered with pleura & suspended by its root
14Mudoogo Edgar
15. • Apex – The blunt superior end of the lung. It projects upwards, above the level of
the 1st rib and into the floor of the neck.
• Base – The inferior surface of the lung, which sits on the diaphragm.
• Lobes (two or three) – These are separated by fissures within the lung.
• Surfaces (three) – These correspond to the area of the thorax that they face. They
are named costal, mediastinal and diaphragmatic.
• Borders (three) – The edges of the lungs, named the anterior, inferior and posterior
borders.
15Mudoogo Edgar
17. Oblique fissure – Runs from the inferior border of the lung in a superoposterior direction, until it
meets the posterior lung border.
Horizontal fissure– Runs horizontally from the sternum, at the level of the 4th rib, to meet the oblique
fissure.
17Mudoogo Edgar
19. Bronchopulmonary Segments
• are the anatomic, functional, and surgical units of the lungs
• Is pyramid shaped, with the apex at the lung root;
• Is the largest subdivision of a lobe;
• Is surrounded by connective tissue;
• Has separate segmental artery, segmental (tertiary) bronchus, lymph vessels & autonomic
nerves;
• Segmental veins lie in the connective tissue b/w adjacent bronchopulmonary segment;
• Diseased segment can be removed surgically without affecting the function of other segments
•
19Mudoogo Edgar
21. Main characteristics of a bronchopulmonary
segment
• It is a subdivision of a lung lobe.
• It is pyramid shaped, with its apex toward the lung
• root.
• It is surrounded by connective tissue.
• It has a segmental bronchus, a segmental artery, lymph
• vessels, and autonomic nerves.
• The segmental vein lies in the connective tissue between adjacent bronchopulmonary
segments.
• Because it is a structural unit, a diseased segment can be removed surgically
21Mudoogo Edgar
22. RIGHT LUNG BRONCHOPULMONARY
SEGMENTS
Upper lobe Apical
anterior
posterior
Middle lobe medial
lateral
Lower lobe superior
Medial basal
Anterior basal
Lateral basal
Posterior basal
22Mudoogo Edgar
23. LEFT LUNG BRONCHOPULMONARY
SEGMENTS
Upper lobe apical
anterior
posterior
Superior lingular
Inferior lingular
Lower lobe superior
Medial basal
Anterior basal
Lateral basal
Posterior basal
23Mudoogo Edgar
24. R-A PALM Seed Makes Another Little Palm
L-ASIA ALPS
24Mudoogo Edgar
25. Clinical Notes
1. PLEURAL EFFUSION The pleural normally contains 5- 10ml of clear fluid.
The formation results from hydrostatic & osmotic pressures. The pleural fluid is
normally absorbed by the capillaries of visceral pleura. Any condition that
increases the production of fluid result in abnormal accumulation of fluid
2. PLEURISY or PLEURITIS is the inflammation of pleura
3. PNEUMONIA inflammation of lungs
4. PLEURAL RUB pleural surfaces become rough & produce friction & a can be
heard with stethoscope
5. PLEURAL ADHESIONS visceral & parietal pleura adhere to each other
6. PNEUMOTHORAX air in the pleural cavity (from lungs or chest wall)
7. HYDROPNEUMOTHORAX air in pleural cavity associated with serous fluid
8. PYOPNEUMOTHORAX air in pleural cavity associated pus
9. HEMOPNEUMOTHORAX air in pleural cavity associated with blood
25Mudoogo Edgar
27. Clinical Notes
EMPYEMA collection of pus in pleural cavity without air
COMPRESSION OF THE TRACHEA bilateral enlargement
of thyroid gland
AORTIC ARCH ANERYSM dilation of aortic arch
TRACHEITIS OR BRONCHITIS give rise to a raw burning
sensation felt deep to the sternum instead of actual pain
INHALED FOREIGN BODIES common in children, tend to
enter right bronchus instead of left because the right bronchus is
wider & more direct continuation of the trachea
BRONCHOSCOPY examination of interior of trachea through
bronchoscope
TRACHEOSTOMY cutting the trachea 27Mudoogo Edgar