inner layer which covers the lung & lines its fissures
Pariatal
lines thoracic wall from inside & lines chest wall
& covers the mediastinum.
The visceral and parietal pleurae are continuous together around
the root of the lung.
Pulmonary Ligament
The pleura extends downwards as a fold below the root called the pulmonary ligament.
Functions : Provides DEAD SPACE
into which the :
Lung root descends with descent of the diaphragm.
Pulmonary veins can expand (exercise).
Pleural Cavity
The closed cavity
between the visceral and
parietal pleurae
contains a thin film of fluid (PLEURAL
FLUID) and encloses the lung.
Lubricates the pleural surfaces and allows
the layers of pleura to slide smoothly over
each other during respiration
Inflammation of the pleura makes
the pleural surfaces rough. The
resulting friction (pleural rub) is
detectable with a stethoscope.
Visceral Pleura
Absent in :
Hilum of the Lung
Between the 2 layers of
pulmonary ligament
Pariatal
Costal Pleura
Lining the :
Sternum
Ribs
Costal Cartilages
Intercostal spaces
Sides of vertebral column
Diaphragmatic pleura
Cervical Pleura
covers the apex of
the lung.
It is attached above by the
suprapleural membrane
Mediastinal Pleura
which covers the sides of the mediastinum.
Relations: as mediastinal surface of the lungs.
Pleural Recesses
They are narrow extensions of the pleural cavity.
Allows the lungs to expand during deep inspiration.
Sites
Costodiaphragmatic
recess {Costophrenic
angle}
lies between the costal & diaphragmatic pleura
along the INFERIOR MARGIN of the pleura
Accumulation of fluid in the pleural cavity , the fluid tends to gravitate
towards the recesses >> obliterates the costophrenic angle will cause an
opacity which obliterates the angle. Pleural Effusion { HYDROTHORAX }
In thoracocentesis, inserting the needle into the 9th intercostal space in the
mid-axillary line during expiration will avoid the inferior border of the lung.
Costomediastinal
recess
lies between the costal and mediastinal pleura
along the anterior margin of the pleura
Overlies the heart.
Lies at the anterior ends of the left
4th and 5th intercostal spaces.
During full inspiration it becomes
occupied by the lingula of the left lung.