Trachea, oesopha & thoracic duct r

.Explain the extent, relations, blood supply, nerve supply, lymphatic drainage of the trachea.
3. Explain the applied anatomy of the trachea.
4. Define esophagus, explain the beginning, course, relations, constrictions, termination, nerve supply,
blood supply, and lymphatic drainage of esophagus
5. Explain the applied anatomy of the esophagus
6. Define thoracic duct, explain the origin, course, relations, termination, tributaries, and areas of
drainage of the thoracic duct
7. Explain the applied anatomy of the thoracic duct

1. TRACHEA,OESOPHAGUS &
THORACIC DUCT
All the information, including the images and pics collected from
different sources is strictly for teaching purposes only.
G R N 1

2. Learning objectives
1.Explain the extent, relations, blood supply, nerve supply ,lymphatic drainage of trachea.
3. Explain the applied anatomy of trachea.
4. Define esophagus ,explain the beginning, course, relations, constrictions, termination ,nerve supply,
blood supply and lymphatic drainage of esophagus
5. Explain the applied anatomy of esophagus
6. Define thoracic duct ,explain the origin, course, relations,termination, tributaries and areas of
drainage
of thoracic duct
7. Explain the applied anatomy of the thoracic duct
G R N 2

3. The trachea(Wind pipe)
•10–12 cm long flexible (can rapidly alter in length),non
collapsible tube(kept patent by incomplete C-shaped
tracheal cartilages).
•Descends from the larynx, from the level of the sixth
cervical vertebra into the superior mediastinum, to
the level of disc between 4th and 5th thoracic vertebra
where it divides into right and left principal (pulmonary)
bronchi( note :Tracheal bifurcation and both main
bronchi lie in the middle mediastinum)
•Flattened posteriorly so that in transverse sectionit is
shaped like a letter D
•Formed of cartilage and fibromuscular membrane.
G R N 3

4. G R N 4

5. G R N 5

6. The incomplete C-shaped tracheal cartilages are
connected by Lig. anularia, which comprise elastic
connective tissueand enable the elongation of
the trachea for up to 5 cm during deep
inspiration.
Its external transverse diameter in adults is 20
mm (males) and 15 mm (females) and
The luminal transverse diameter
•in the first postnatal year ≤ 4 mm
•later childhood -equal(in mm) to age in years and
•in adults ~12mm
G R N 6

7. Cervical part of the trachea -anterior relations
1.Skin , Superficial and deep(pretracheal) fasciae,
2.Sternohyoid and sternothyroid(overlap the trachea)
3.Isthmus of the thyroid gland (opposite second to
fourth tracheal cartilages) –crosses and connects
both the lobes.
4.Anastomotic artery (lies above the isthmus and
connects the bilateral superior thyroid arteries)
5.Jugular venous arch (crosses the trachea below)
6.Inferior thyroid veins
G R N 7

8. Thoracic part of the trachea -anterior relations
Manubrium sterni with the
attachments of sternohyoid &
sternothyroid, and thymic remnants
lie anterior to it as it descends
through the superior mediastinum.
At a lower level, the aortic arch, the
brachiocephalic and left common carotid arteries,
left brachiocephalic vein, deep cardiac plexus and
some lymph nodes are all anterior to the trachea.
G R N 8

9. G R N 9
(Note the anterior relations of the thoracic part of trachea)

10. Cervical part of the trachea -lateral relations
1.Paired lobes of the thyroid gland(
descend up to the level of fifth or sixth
tracheal cartilage)
2.Common carotid and inferior thyroid
arteries,
3.Recurrent laryngeal nerves ( ascend on
each side, in or near the groove between
the sides of the trachea and oesophagus-
tracheoesophageal groove)
G R N 10

11. On the right are:
1.Right lung and pleura,
2.Brachiocephalic artery &
right brachiocephalic vein,
3.Superior vena cava,
4.Right vagus nerve and
5.Azygos vein.
On the left are:
1.Arch of the aorta,
2.Left common carotid and
3.Left subclavian arteries.
The left recurrent laryngeal nerve at first lies under
the arch , then situated between the trachea and aortic
arch, and then in the groove between the trachea and the
oesophagus.
Thoracic part of the trachea -lateral relations
G R N 11

12. Right lateral view Left lateral view
Note the right and left lateral relations of the thoracic part of trachea

13. G R N
13

14. Trachea -Posterior relations
•Oesophagus lies, and separates it
from the vertebral column.
G R N 14

15. Vascular supply and Innervation of the Trachea
Arterial supply:
Cervical part -mainly by branches from the
inferior thyroid arteries
Thoracic portion -by branches of the
bronchial arteries
•The tracheal veins-drain into the brachiocephalic veins
via the inferior thyroid plexus
•The lymphatic vessels -drain into the pretracheal and
paratracheal nodes.
•Innervation: by the branches from vagi, recurrent
laryngeal nerves and sympathetic trunks.
G R N 15

16. 1.Tracheal compression–enlargement of thyroid, thymus, lymph nodes
2.Tracheal intubation-
3.Tracheostomy-emergency procedure to relieve laryngeal obstruction
in various clinical conditions.
4.Trachea is normally palpated in the supra sternal notch in the midline.
Shift of trachea to any side indicates mediastinal shift.
Applied anatomy
G R N 16

17. Tracheal intubation-
Tracheal intubation-refers to the
insertion of atracheal tubedown the
trachea.
Commonly performed duringsurgery,
for inhalational(general) anaesthesia.
The tube inserted down the trachea is
connected to a machine that monitors
the airflow, oxygenation and several
other metrics.
G R N
17

18. G R N
18

19. Tracheotomy
Tracheotomy consists of making an incision
on the front of the neck and opening a
direct airway through an incision in the
trachea.
The resultingopeningcan serve
independently as an airway or as a site for
a tracheostomy tube to be inserted (allows
a person to breathe without the use of
their nose or mouth).
In order to limit the risk of damage to the
recurrent laryngeal nerves(the nerves that
control thelarynx/voice box), the tracheotomy
is performed as high as in the trachea.
G R N
19

20. OESOPHAGUS
(the gulletor food pipe)
G R N 20

21. OESOPHAGUS
Muscular tube ( 25 cm long), flat in its upper 2/3 &
rounded in lower 1/3.
Connects the pharynx to the stomach.
It beginsin the neck, level with the lower border of
the cricoid cartilage (corresponds to 6
th
CV
posteriorly).
Enters the thorax via its inlet and descends through
the superior and posterior mediastina, in front to the
vert.column following the cervicothoracic curvatures
of the vertebral column;
Narrowest part of the alimentary tract (except for
the vermiform appendix), Collapsed at rest G R N 21

22. G R N 22

23. G R N 23

24. OESOPHAGUS
Shows two shallow curves in
coronal plane(Lateral curvatures)-
Inclines to the left after it’s
beginning ,as far as the root of the
neck, then returns to the median
plane near the 5
th
thoracic V.
Again, deviates to left at the 7
th
thoracic vertebra
(At it’s beginning and near the 5
th
thoracic vertebra it is in the
median plane)
G R N 24

25. Passes through the
diaphragm(aperture
known as esophageal
hiatus) levelwith the 10
th
thoracic vertebra.
Ends at the gastric
cardiac orifice(known as
GE junction) level with
the 11th thoracic vertebra
OESOPHAGUS
G R N 25

26. CONSTRICTIONS OF THE OESOPHAGUS
•It has 4 constrictions(narrowings)-
-at thebeginning (15 cm from the incisor teeth),
-where it is crossed by the aortic arch (22.5 cm from the incisor
teeth),
-where it is crossed by the left principal bronchus (27.5 cm from the
incisors),
-as it passes through the diaphragm (40 cm from the incisors).
•These measurements are important clinically when you pass
instruments along the esophagus
G R N 26

27. G R N 27

28. Anterior Relations of the oesophagus:
Cervical part:
1.Trachea -attached to it by
loose connective tissue
Thoracic part
1.Trachea ,
2.Left main bronchus,
3.Right pulmonary artery,
4.Pericardium (separating it
from the left atrium) and
5.Diaphragm
G R N 28

29. Lateral relations of cervical part of oesophagus
on each side
1.Recurrent laryngeal nerves ascend in
or near the tracheo-oesophageal
groove.
Further Laterally
2.Posterior part of the thyroid lobe.
3.Common carotid arteries (in carotid
sheath)
4.Thoracic duct ( for a short distance
along its left side) .
G R N 29

30. G R N 30

31. Thoracic part of oesophagus
Left lateralrelations
In the superior mediastinum
1.Recurrent laryng. nerve,
2.Thoracic duct,
3.Left subclavian artery,
4.Terminal part of aortic arch
5.Left pleura
In the posterior mediastinum
1.Descending thoracic aorta
2.Left pleura.
G R N 31

32. Thoracic part of oesophagus
Right lateral
1.Azygos vein (as it arches
forwards above the right
main bronchus to join the
SVC)
2.Right pleura,
G R N 32

33. Posterior relations in thorax
1.Vertebral column, Longus
colli muscle and prevertebral
layer of deep cervical fascia.
2.Right posterior intercostal
arteries,
3.Thoracic duct,
4.Terminal parts of the
accessory hemiazygos and
hemiazygos veins
5.Aorta(near the diaphragm).
G R N 33

34. Oesophagus seen from behind
G R N 34

35. THORACIC DUCT RELATION TO THE
OESOPHAGUS
In the lower part of the posterior
mediastinum,
thoracic duct is to the right and
behind the oesophagus
as it ascends, it becomes posterior
to the oesophagus
and at the level of the fifth
thoracic vertebra crosses to the
left of the oesophagus and
ascends on the left.
G R N 35

36. VAGUS NERVES RELATION TO
THE OESOPHAGUS:
Below to the
pulmonary(lung) roots,
the Vagus nerves
descend in contact with
the oesophagus,
the left vagus comes in
front and
the right behind (LARP).
The vagi subsequently
unite to form a plexus
around the oesophagus.
G R N 36

37. INNERVATION
G R N 37

38. The cervical oesophagus-
supplied by the inferior thyroid arteries
The thoracic oesophagus-
1.Bronchial arteries
Left side-2 bronchial arteries arising from
descending thoracic aorta.
Right side-One bronchial artery arising from 3
rd
posterior intercostal artery.
2.Oesophageal branchesof the descending
thoracic aorta(four to five).
3.Branches from the left phrenic and left gastric
arteries
VASCULAR SUPPLY
G R N 38

39. Arterial supply
G R N 39

40. Venous drainage
G R N 40

41. Applied anatomical aspects
•Congenital anomalies-oesophageal atresia and tracheoesophageal
fistula
•Esophageal webs and rings (Schatzki ring)
•Esophageal diverticula
•Achalasia or cardio spasm
•Gastroesophageal reflux disease(GERD/GORD)
•Carcinoma of esophagus
•Hiatus hernia
•Esophageal stenosis
G R N 41

42. Congenital anomalies-Tracheoesophageal fistulas

43. Esophageal web stenosis
in barium swallow
examination frontal view
Endoscopic image of Schatzki
ring, seen in the esophagus with
the gastro-esophageal junction
in the background.
Esophageal web
Schatzki ring (red arrow)
at the distal oesophagus
Oesophageal webs and rings (Schatzki ring)

44. Achalasia cardiae, cardiospasm, or esophageal aperistalsis
•An esophageal motility disorder involving the smooth muscle layer of the
esophagus and the lower esophageal sphincter (LES) due to imbalance in excitatory
and inhibitory neurotransmission.
•It is characterized by incomplete LES relaxation, increased LES tone, and lack of
peristalsis of the esophagus (inability of smooth muscle to move food down the
esophagus) in the absence of other explanations like cancer or fibrosis
•The main symptoms of achalasia are dysphagia (difficulty in swallowing),
regurgitation of undigested food, chest pain behind the sternum
•Manometry :Pressure of LES <26mm Hg is normal,>100 is considered as achlasia, >
200 is nutcracker achlasia.

45. BARIUM SWALLOW SHOWING ACHALASIA "Bird's beak" appearance,
typical in achalasia
(cardiospasm).

46. Nasogastric intubationis a medical process involving the insertion of a plastic tube
(nasogastric tubeor Ryle's tube ) through the nose, past the pharynx, oesophagus and down
into the stomach.

47. Thoracic duct
G R N 47

48. ▪45 cm in length , begins in front of
L1 vertebra in the abdominal cavity
as a dilated sac-the cisterna chyli.
▪Drains lymph from lower limbs,
pelvic cavity, abdominal cavity, left
side of thorax, and left side of the
head, neck and left upper limb.
▪Enters the thoracic cavity through
aortic opening of the diaphragm
along with the aorta and azygos
vein.
Thoracic duct
G R N 48

49. Upper end of Chysterna chyli is the beginning
of thoracic duct. At its origin, the thoracic
duct is usually 5 mm in diameter,
diminishing in calibre as it ascends.
It may divide in its mid course into two
unequal vessels that soon reunite, or into
several small branches that form a plexus
before continuing as a single duct.
The thoracic duct has several valves(hence
beaded appearance) corresponding to sites
exposed to pressure.
At its termination, a bicuspid valve faces into
the vein to prevent or reduce reflux of blood.
G R N 49

50. 50
THORACIC DUCT…..
▪In the thoracic cavity runs in the posterior
mediastinum lying between the aorta and
azygos vein
▪As it ascends upward it crosses to the left at the
level of disc between T4 and T5
▪At the root of the neck, it turns laterally at the
level of the transverse process of the 7
th
cervical vertebra anterior to the vertebral
artery and vein, the left sympathetic trunk,
thyrocervical trunk, left phrenic nerve and the
medial border of scalenus anteriorbut
posterior to the left common carotid artery,
vagus nerve and internal jugular vein. G R N 50

51. Thoracic duct
▪It then arches forwards and descends to
enter the left venous angle(junction of
internal jugular and subclavian veins)
▪Before termination, it receives the left
jugular, subclavian and broncho-mediastinal
trunks
•The lymph in the thoracic duct has milky
appearance because of fat droplets that
enter after the absorption from GUT.
G R N 51

52. TRIBUTARIES
Bilateral descending thoracic lymph
trunks from intercostal lymph nodes of
the lower six or seven intercostal
spaces of both sides traverse the
retrocrural space and join the lateral
aspects of the thoracic duct in the
abdomen immediately after its origin.
Bilateral ascending lumbar lymph
trunks from the upper lateral aortic
nodes join thoracic duct at a variable
level
The upper intercostal trunks draining
the intercostal nodes in the upper five
or six left intercostal spaces.
G R N 52

53. The thoracic duct injury
•The variable course of the thoracic duct, coupled with failure to identify it at surgery, may lead to its inadvertent
incision or transection.
•The incidence is between 0.2% and 3% , during esophageal surgery particularly with trans hiatal and
thoracoscopic procedures.
•Thoracic duct laceration is a potentially life-threatening complication: mortality rates are more than 50% with
conservative management and as high as 10–16% even after early surgical duct ligation.
•Rupture of the thoracic duct leads to leakage of chyle(Chylothorax)
•Injury should be suspected in the postoperative period if there is an enlarging mediastinal silhouette on serial
chest radiographs, or if there is significant drainage of a cream-colored liquid from the chest or abdominal
drains.
•In cases of uncertainty, an electrophoretic confirmation for the presence of chylomicrons in the pleural fluid is
diagnostic.
G R N 53

54. G R N 54