Pleura & Lungs

PAA 1015

الرحيم الرحمن الله بسم

THE PLEURA

• Definition : Is a serous membrane formed of two layers

1. Parietal layer: outer layer lines the inner

surface of the chest wall.

2. Visceral layer: inner layer adherent to the lung tissues and dips at the fissures of the lung.

3. Pleural sac (cavity): is the sac between the two layers .

Parts of the pleura

• Parts :

1. costal pleura

2. mediastinal.

3. diaphragmatic

4. cervical pleura

( Apex)

Pleura

• Parts of the pleura

SURFACES OF THE PLEURA 1. Apex : extend above the clavicle covered by

suprapleural membrane from Transverse process of 7th cervical vertebra to inner border of first rib.

2. Base (diaphragmatic surface): related to the diaphragm that separates it from the abdominal organs (stomach fundus, spleen and left lobe of the liver at left side and the right lobe of the liver at right side).

3. Medial surface (mediastinal): related to mediastinum contents.

4. Sternocostal surface: related to sternum, ribs and intercostal muscles.

SURFACE ANATOMY OF THE PLEURA

1) Apex (cervical pleura): present 1inch (2.5cm) above the medial 1/3 of the clavicle (it is covered by suprapleural membrane).

2) Anterior border: from the apex descend behind the

sternoclavicular joint then : A) At left side descend to 2 costal cartilage then to 4 C.C.

Then makes curve to the left 1 inch forming cardiac notch to reach 6th costal cartilage.

B) At the right side: descend direct from 2 costal. Cartilage to the 6th costal cartilage (no cardiac notch).

Surface anatomy of the pleura

3) Inferior border: common for both sides from 6th costal cartilage to 8th rib at midclavicular line then to the 10th rib at midaxillary line then to the 12th rib (12th vertebral spine).

4)Posterior border: for both lungs from 12th rib to

the apex it ascend along the vertebral column (vertebral border).

N.B: The only difference at the anterior border.

Pleural reflections

Are places where the pleura reflected (changes)

From visceral into parietal layer, it occurs at two sites:

1)Around the hilum of the lung.

2)At the pulmonary ligament extend from below the hilum to Diaphragm.

Pleural recesses

• Are spaces OR parts of the pleural sac that occupied by the lung only in deep inspiration

• They are two (reserve space):1) Costodiaphragmatic recess: along the inferior

border of the pleura here the lung separated from the pleura by two spaces at the midaxillary

line. This recesses used clinically for drainage of the Pleural effusion as water in hydrothorax or excess air as in Pneumothorax.

Pleural recesses

2) Costomediastinal recess: is present along the anterior border of the lung.

It is not important clinically for pleural tapping ( parasenthesis) .

Nerve supply of the pleura

1) visceral layer is non sensitive for PAIN and supplied by autonomic (sympathetic nerves and vagus

parasymp.). 2) Parietal layer : is sensitive for pain supplied by

– Phrenic nerve That supplies the medial surface and the central part of the base.

– Intercostal nerves: supply the sternocostal surface and the Peripheral part of the base diaphragmatic surface.

Blood supply: intercostal arteries.

THE LUNG

Pyramidal shape and has the following:

A) BORDERS: (surface anatomy) a) Apex: same as the pleura.b) Anterior border: same as the pleura

c) Inferior border: Begin at 6th costal cartilage, and crosses 6th rib at midclavicular line then cross the

a) 8th rib at midaxillary line to end at 10th rib posterior

b) (10th thoracic spine) two ribs above the pleura.

d) Posterior border: from 10th rib ascend to the apex.

lung1)Lung 2)Horizontal fissure of right lung 3)Heart 4)Acute margin 5)Obtuse margin 6)Brachiocephalic trunk 7)Trachea 8)Left common carotid artery 9)Left subclavian artery

Lung • FISSURES:

Surface anatomy of the fissures:

1) Oblique fissure for both lungs start at 3rd thoracic spine (at the level of spine of scapula) then cross the 5th rib at midaxillary line and descend to 6th costal cartilage (costochondral junction) near the inferior border of the lung.

2) Horizontal fissure for the right lung only : start at 4th costal cartilageThen pass posterior to meet the oblique fissure at midaxillary Line .

Lung

• Right lung Left lung

Lung

• Right lung Left lung

• Shorter and wider . loner

• Has three lobes (600-700gm) . 500 gm of

• No cardiac notch . two lobes

• has notch

• Has two fissures . only one

Lung

B) SURFACES OF THE LUNG: a) Costal Surface: related to chest wall.b) Base (diaphragmatic surface): related to the

diaphragm separate it from stomach , spleen ,left lobe of liver at left side , and the right lobe of liver at right side.

c) Medial (mediastinal) surface related to the mediastinum and contain the hilum.

RELATION OF THE MEDIASTNAL (MEDIAL) SURFACE

A) RIGHT LUNG :

1) ANTERIOR TO THE HILUM: cardiac impression for right atrium, Right phrenic nerve and pericardium. Then superior vena cava and Right brachiocephalic vein above the cardiac

impression.

Right Lung 2) BELOW THE HILUM: groove for Inferior vena cava .

3) POSTERIOR TO THE HILUM: esophagus and Azygos vein posterior to the right border of the esophagus

4) ABOVE THE HILUM: groove for arch of Azygos vein, above this groove there is impression for trachea right vagus and esophagus.

• N.B: The arch of Azygos separates the trachea and esophagus from the lung

Right lung

Relation to medial surface of left lung

1) ANTERIOR TO THE HILUM: cardiac impression for left ventricle, Left auricle, phrenic nerve and pericardium.

2) POSTERIOR TO THE HILUM: groove for descending thoracic

aorta

3) ABOVE THE HILUM: groove for arch of aorta above it there are Two grooves for left common carotid and left subclavian arteries.

Esophagus, thoracic duct and left recurrent laryngeal nerve

posterior to the Grooves related to the branches of the aortic arch .

4) Below the hilum : groove for esophagus .

Left lung

HILUM OF THE LUNG

A) THE HILUM OF THE RIGHT LUNG CONTAINS:

1) Major structures:

a) Eparterial and Hyparterial ----------- bronchus.b) Pulmonary artery in between and in front of the

bronchi.c) Superior and inferior pulmonary veins below the

artery

Hilum of right Lung 2) Minor contents: a) Bronchopulmonary lymph nodes .

b) Bronchial artery from the 3rd posterior intercostal

artery (First aortic posterior intercostal) or from upper left bronchial

Bronchial veins that end at Azygos vein.

c) Pulmonary nerve plexuses: Anterior and posterior plexus to the bronchi formed of sympathetic and parasympathetic (vagus).

Hilum of the right lung

THE HILUM OF THE LEFT LUNG

• 1) Major contents:

a) left bronchus ----- 1 b) Pulmonary artery above the bronchus.

c) Superior and inferior pulmonary vein below the artery.

Hilum of the left lung

Minor contents:

a) lymph nodes (bronchopulmonary)--------------------- b) Pulmonary nerve plexuses: One anterior and one

posterior to the Main bronchus

c) Bronchial arteries are two arise from the descending aorta (they are superior and inferior)

d) The bronchial Veins end at Hemiazygos veins in the left side.

Hilum of the left lung