2. TRACHEA (WINDPIPE)
PATENT TUBE FOR PASSAGE OF AIR TO AND FRO FROM LUNGS, ITS
UPPER END IS CONTINOUS WITH LOWER END OF LARYNX.
10 TO 15 CM IN LENGTH; LIES IN MIDLINE OF NECK
EXTERNAL DIAMETER IS 2 CM IN MALE
1.5 CM FEMALE
LUMEN SIZE IS ABOUT 2- 3MM AT 1 YEAR ( ie increases 1mm/yr upto
12yrs of age)
12 MM IN ADULTS
UPPER END LIES AT LEVEL OF CRICOID CARTILAGE (C6 LEVEL)
LOWER END BIFURCATE AT LOWER BORDER OF T4( BIFURCATION IS
CARINA) ; IT SLIGHTLY DEVIATES TO RIGHT
3. STRUCTURE
HAS A FIBROELASTIC WALL SUPPORTED BY
CARTILAGINOUS SKELETON FORMED BY ‘C-
SHAPED’ RINGS (16-20) DEFICIENT POSTERIORLY
POSTERIORLY THERE IS GAP FILLED BY
FIBROELASTIC MEMBRANE AND TRACHEALIS
MUSCLE(transversely arranged)
LUMEN LINED BY CILIATED COLUMNAR EPITHELIUM
NEAR LOWER END IT DEVIATE SLIGHTLY TO RIGHT
SIDE
4. ARTERIAL SUPPLY :INFERIOR THYROID ARTERY
VENOUS SUPPLY : INTO LEFT BRACHIOCEPHALIC VEIN
LYMPHATICS :PRETRACHEAL AND PARATRACHEAL
NODES
NERVE SUPPLY:
PARASYMPHATHATIC
VAGUS AND RECURRENT LARYNGEAL NERVE(sensory
and secretomotor to mucous membrane)
SYMPATHETIC:
FROM MIDDLE CERVICAL GANGLION ALONG INFERIOR
THYROID ARTERY(vasomotor function)
5. Clinical Anatomy
In Radiographs, Trachea is seen as a vertical
translucent shadow due to contained air in
front of cervicothoracic spine.
Tracheostomy: surgical procedure done to
allow direct air entry into trachea; usually
done below the 4th ring .
7. BRONCHI
The trachea divides at lower border of T4 into 2 primary
principal(main) bronchi:
Right main bronchus: (2.5 cm long)
Shorter, wider and more straight ;makes an angle of 25
degree with bifurcation (Increased chance of aspiration
of inhaled particlces or foreign bodies into right lung)
enter lung through the hilum, divides into three
secondary lobar bronchi(upper, middle and lower lobar
bronchi)
8.
9. Left main Bronchus: (5cm)
Longer, narrower, more oblique(angulated);
makes an angle of 45 degree
( decreased drainage of secretions stasis
increased infection destruction and
dilatation of bronchi increased chance
of bronchiectasis in left lung
Divides into two secondary/ lobar bronchi(
upper and lower)
11. Each secondary bronchus divides into tertiary/ segmental
bronchi
One for each bronchopulmonary segment( 10 on right side; 9
on left side)
Tertiary bronchi divides into terminal bronchioles and still
smaller branches are called respiratory bronchioles
Each respiratory bronchiole aerates small part of lung:
pulmonary unit
12. Pulmonary unit
Respiratory bronchiole ends in alveolar ducts,
leads to alveolar sacs and alveoli(pulmonary
unit); surrounded by a network of blood
capillaries for gas exchange
14. BRONCHO PULMONARY
SEGMENTS
Well-defined anatomic, functional and surgical
sectors of lung
Each one is aerated by tertiary
bronchus(segmental)
pyramidal in shape ;apex directed towards root of
lung
Has its own segmental bronchus, segmental
artery, autonomic nerves, lymph vessels
The segmental venules lies in the inter- segmental
connective tissue planes between the adjacent
segments.
A diseased segment can be removed surgically,
because it is a structural unit; surgeon works
along the segmental veins
15.
16. Broncho pulmonary segments
Right side -10 segments
wider, more in line with trachea, shorter than left
Upper lobe Middle lobe Lower lobe
1 apical 1.Lateral 1.superior
2 anterior 2.Medial 2.ant.basal
3 posterior 3.post.basal
4.medialbasal
5.lat.basal
21. Bronchopulomary segment has its own
separate artery
Do not have its own vein; intersegmental veins:
each segment has more than one vein;each vein
will drain more than one segment
Bronchopulmonary segments are not
bronchovascular segment because it does
not have its own vein
22. Clinical anatomy
Usually infection of a bronchopulmonary
segment remains restricted to it except TB
,bronchogenic CA
MC segment involved in aspiration pneumonia
Overall: RT lowerlobe superior > Rt upper lobe
post-basal segment
Sitting/ standing: RT LL post-basal
Supine: RT LL superior segment > RT upper
lobe postbasal
Bending forward: RT middle lobe
23. ROOT OF LUNG
Short, broad pedicle connects medial surface of
lung to mediastinum
Root of lung lie opposite to bodies of T4,T5,T6
It has hilum where structures enter and exit
24. ROOT OF LUNG(structures)
Principal bronchus at left side
Eparterial and hypoarterial bronchus on rt
one Pul.artery
2 pulmonary veins( superior and inferior)
Bronchial arteries 1 on rt side ; 2 on left side
Bronchial veins
Ant. and posterior pulmonary plexus of nerves
Bronchopulmonary LN. and lymphatics
Areolar tissue
25. Arrangements of Structures -
Root of The Lung
1.From anterior to posterior: It is similar on the two sides.
a. Superior pulmonary vein
b. Pulmonary artery
c. Bronchus
2.From above to downwards. It is different on the two sides.
Right side:-
a. Eparterial bronchus
b.Pulmonary artery
c.Hyparterial bronchus
d.Inferior pulmonary vein
Left side:-
a.Pulmonary artery
b.Bronchus
c.Inferior pulmonary vein
26.
27.
28. PLEURA
It is a closed serous sac which surrounds
the lung and invaginated from its medial
side by the root of lung.
It has 2 – layers:
parietal pleura,from somatopleural
layer, pain sensitive which lines the
thoracic cavity. &
visceral pleura which surrounds the lung
,from splenchopleural mesoderm,pain
insensitive , separated by a pleural
cavity.
Pleural cavity:
Contains 5-10 ml. of serous fluid which
lubricates both sufaces and allows the
lungs to move free during respiration.
29. Divisions of parietal pleura
1- Cervical
pleura(cupula)
It is part of parietal
pleura which protrudes
up into the root of the
neck.
2-Costal pleura:
It lines inner surface of
ribs, costal cartilages,
intercostal muscles and
back of the sternum.
3-Diaphragmatic
pleura:
It covers upper surface
of the diaphragm.
4-Mediastinal pleura:
It covers mediastinal
surface of the lung.
30. SURFACE ANATOMY OF PLEURA
Apex:
lies one inch above the medial 1/3 of
the clavicle.
Anterior margin : extend from
sternoclavicular joint to mid point of
sternal angle medially.
Right pleura: upto Midpoint of
xiphisternal joint
Left pleura: at 4th costal cartilage
arches outward and descend along
sternal margin upto 6th costal cartilage.
Inferior margin : passes round chest
wall, on the 8th rib in midclavicular line,
10th rib in mid-axillary line and 12th rib at
the lateral border of sacrospinalis
muscle. Then it passes horizontally a
little below the 12th rib 2 cm lateral to
12th thoracic spine.
Posterior margin : 2 cm lateral to 12th
thoracic spine to 2 cm lateral to 7th
cervical spine
31. Pleural Recesses
Costodiaphragmatic recess:
lies between costal &
diaphragmatic parietal
pleura along the inferior
border.
Extend from 8th to 10th rib in
mid-axillary line
Costomediastinal recess :
lies between costal &
mediastinal parietal pleura
along the anterior border.
The lung reaches these
recesses only in deep
inspiration.
32. Nerve Supply of Pleura
Parietal pleura….
Costal P.P….by
intercostal nerves.
Mediastinal P.P….by
phrenic nerve.
Diaphragmatic P.P.:
1-Medially by phrenic
nerve.
2-Peripheral part.. by
lower 6 intercostal
nerves.
Visceral pleura…
sympathetic N.S. from
pulmonary plexus.
33. LUNGS
Rt lung = 700 gm(50-100g heavier than left
lung)
Lt lung= 600-650 gm, It is conical In shape.
It has an apex,
a base resting on diaphragm
It has 3 borders: anterior, posterior, inferior
2 surfaces:
The costal surface of each lung borders the
ribs (front and back).
On the medial (mediastinal) surface, the
bronchi, blood vessels, and lymphatic vessels
enter the lung at the hilum.
34. Apex:
Blunt, lies above level of ant end of first rib.
projects into root of the neck (one inch above the medial 1/3 of the
clavicle). It is covered by cervical pleura, suprapleural membrane
It is grooved anteriorly and medially by subclavian vessels.
Base: (inferior= diaphragmatic surface)
Semilunar, concave, rests on diaphragm
35. Borders: Anterior & Posterior
Anterior border :
sharp, thin and overlaps the heart.
Anterior border of left lung presents a cardiac notch at its lower end, at 5
costal cartilage level + thin projection called the lingula below the cardiac
notch.
Posterior border :
rounded, thick and lies beside the vertebral column c7 to t10.
Inferior border: sharp, separate base from costal and medial surface
36. Surfaces: Costal & Mediastinal
Costal surface:
Convex.
Covered by costal pleura
which separates lung from:
ribs, costal cartilages &
intercostal muscles.
Medial surface:
Anterior (mediastinal) part:
Contains a hilum in the middle
(it is a depression in which
bronchi, vessels, & nerves
forming the root of lung).
Posterior (vertebral) part:
It is related to: bodies of
thoracic vertebrae,
intervertebral discs, posterior
intercostal vessels &
sympathetic trunk.
Lateral & medial surfaces of right lung
37. Mediastinal surface of right lung
Azygos vein and its arch
(posterior and over the
root of the lung).
Vagus nerve posterior to
the root.
Esophagus above and
posterior to the root.
Phrenic nerve anterior to
the root.
Cardiac impression:
related to right atrium.
Below hilum :
Groove for I.V.C.
Cardiac
impression
38. Mediastinal surface of left lung
Descending aorta &
Vagus nerve posterior to
the root.
Arch of the aorta over the
root.
Groove for left common
carotid artery & left
subclavian artery.
Phrenic nerve anterior to
the root.
Cardiac impression :
related to left ventricle.
Cardiac
impression
39. Differences b/w RT and LT
lung
RIGHT LUNG
Has 2 fissures ( oblique
and horizontal) and 3
lobes(
upper,middle,lower)
Anterior border is
straight
Larger heavier, wt=700g
Shorter and broader
LEFT LUNG
Has one fissure(
horizontal) and 2
lobes(upper and
lower)
Anterior border is
interrupted by the
cardiac notch
Smaller and lighter,
wt=600g
Longer and narrower
41. Fissures
Oblique/ major fissure: line drawn from T2
spine to 5th rib in mid axillary line to 6th rib
in mid clavicular line ( 6-7cm lateral to
median plane)
Horizontal/ minor fissure: runs horizontally
from mid sternal line at level of 4th costal
cartilage to meet oblique fissure at mid
axillary line at 5th rib and separates a wedge
shaped middle lobe from upper lobe
42.
43. Blood supply of lung
Bronchial arteries (on rt side - 1 artery branch from
intercostal artery and lt – 2 art from descending thoracic
aorta)….. supply oxygenated blood to bronchi , lung tissue
& visceral pleura.
Bronchial veins : drain into azygos (rt) & hemiazygos
veins(lt).
Pulmonary artery which carries non-oxygenated blood from
right ventricle to the lung alveoli.
2 pulmonary veins : carry oxygenated blood from lung
alveoli to the left atrium.
44. Nerve Supply of the lung
Pulmonary plexus :
at the root of lung….is formed of autonomic N.S. from sympathetic &
parasympathetic fibres.
1- Sympathetic from ..2nd to 5th sympathetic trunk - broncho-dilatation and
vasoconstriction.
2- Parasympathetic from….Vagus nerve …. Broncho-constriction and
secretomotor to bronchial glands /and vasodilatation.
45. Lymph drainage of the lungs
Superficial plexus (subpleural):
lies under the visceral pleura
and drain to bronchopulmonary
nodes in the hilum of lung having
multiple valves.
Deep plexus:
Lies along the bronchial tree &
pulmonary blood vessels and drain
into the pulmonary nodes within
the lung substance >
bronchopulmonary nodes (hilum)
>tracheo-bronchial nodes
(bifurcation of trachea) >broncho-
mediastinal lymph trunks to end in
thoracic duct (left) or in right
lymphatic duct (right).
