Pleura, Lungs,. Trachea And Bronchi

Front 1

Parietal

Back 1

- cervical (copula)
- costal
- diaphragmatic
- mediastinal

Front 2

pulmonary ligament

Back 2

- double layer of pleura extending from hilus to diaphragmatic surface
- formed as parietal pleura is reflected onto the lung as visceral pleura
- supports lung in pleural sac (holding lung in place)
- “dead space” for distension of pulmonary veins

Front 3

pleural sac

Back 3

- consists of the visceral pleura, parietal pleura and pleural cavity

Front 4

pleural cavity

Back 4

- potential space between visceral and parietal pleura
- contains thin film of serous fluid
- right and left pleural cavities are closed and do not communicate
- the lungs are not in the pleural cavity
- pressure within pleural cavity lower than atmospheric pressure
- this pressure can be increased by letting air into the cavity (pneumothorax) causing the
lung to collapse
- visceral and parietal pleurae are continuous around root of lung
- adhesion between visceral and parietal pleurae occurs in pleurisy (inflammation)

Front 5

pleural recesses

Back 5

- potential spaces found at regions of pleural reflection where parietal pleura is apposed
to parietal pleura
- allow for lung expansion during inspiration
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a. Left and Right Costodiaphragmatic Recesses
- space between costal pleura and diaphragmatic pleura(between 8th and 10th
intercostals spaces laterally). The left costodiaphragmatic recesses extends
down to the spleen which is related to ribs 9, 10 and 11
b. Costomediastinal Recess
- space between costal pleura and mediastinal pleura due to cardiac notch (from rib 4 to 6)

Front 6

inferior border of lung

Back 6

- inferior border of lung is at ribs 6, 8 and 10 (i.e. 6th rib at midclavicular line,
8th rib at midaxillary line and 10th rib at paravertebral line)
- inferior limit of costodiaphragmatic recess (pleural reflection) is at ribs 8, 10
and 12

Front 7

thoracocentesis

Back 7

- insert needle just above superior margin of rib (to avoid injury to intercostals
neurovascular bundle), usually, in the 7th IS posterior to the midaxillary line
- the layers traversed in a pleural tap, from superficial to deep, are as follows:
skin, superficial fascia, deep fascia, external intercostals muscle, internal
intercostals muscle, innermost intercostals muscle, endothoracic fascia, parietal pleura and (finally) the pleural cavity.

Front 8

endothoracic fascia

Back 8

- internally lines thorax
- plane of
cleavage for the surgical separation of costal pleura from the thoracic wall.
- this endothoracic fascia is continuous with others such as the prevertebral
fascia and transversalis fascia of the abdomen (through openings of the
diaphragm).

Front 9

diaphragm movement

Back 9

bulges up into the pleural cavity, reaching as high as the 4th
intercostals space on the right and the 5th intercostals space on the left

Front 10

blood supply of pleura

Back 10

- visceral pleura is supplied by bronchial arteries
- venous and lymphatic drainage of visceral pleura is similar to that of the lungs
- parietal pleura is supplied by the intercostals, internal thoracic, superior
phrenic and musculophrenic arteries (i.e. by vessels of the thoracic wall,
diaphragm and mediastinum)

Front 11

innervation of pleura

Back 11

- visceral pleura receives sensory innervation via the pulmonary plexus
(autonomics) and is insensitive to pain and touch (but sensitive to stretch)
- sensory supply to parietal pleura is from intercostals and phrenic nerves. It
is extremely sensitive to pain.
- specifically, costal pleura is innervated by intercostals nerves (stimulation of
costal pleura causes local pain)
- the peripheral part of the diaphragmatic pleura is innervated by lower
intercostals nerves (pain referred to lower thoracic wall and anterior
abdominal wall – that is, to areas of skin with the same segmental innervation)
- the central diaphragmatic pleura is supplied by the phrenic nerve (pain
referred to shoulder and neck–distribution of the supraclavicular nerves: C3,
C4)
- the mediastinal pleura is also supplied by the phrenic nerve (pain referred as
above)

Front 12

Surface of lung

Back 12

- costal, ediastinal (medial) and diaphragmatic (basal)
- features of the mediastinal surface of the right lung (due to closely related
structures) include: hilus, cardiac impression and grooves for the esophagus,
azygos vein and SVC
- features of the mediastinal surface of the left lung include: hilus, cardiac
impression and grooves for the aortic arch, descending aorta, subclavian artery
and left branchiocephalic

Front 13

Borders of lung

Back 13

- anterior, posterior and inferior
- anterior border separates costal and mediastinal surfaces; that of the left lung has cardiac notch

Front 14

Lobes of lung

Back 14

- 3 in right lung (upper. middle, lower)
- 2 in left lung (upper and lower)
- lingula of the left lung corresponds to middle lobe of right lung and is formed
by the cardiac notch (due to protrusion of apex of heart to left side) located at
approximately 4th costal cartilage
- secondary (lobar bronchus supplies each lobe

Front 15

fissures of lung

Back 15

a. Oblique
- separates superior and inferior lobes
- follows a line from the third thoracic vertebra posterior to the 6th
costochondral junction anteriorly (curves downward following line of 6th rib)
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b. Horizontal (right lung only)
- separates upper and middle lobes
- follows a horizontal line from the oblique fissure, in the midaxillary line, to the
4th right costal cartilage anteriorly
5. Apex (in copula)
- lies behind middle third of clavicular projecting about 1 in. (2.5 cm) above
anterior portion of first rib into base of neck
- grooved by subclavian artery and separated from structures in neck by
suprapleural membrane (Sibson’s Fascia)