Thoracic surgery L1.pdf gugugugihigihihih

Yvyv

1. Thoracic
surgery
Dr.Saad Mukhlif
Consultant thoracic surgeon

2. objectives
To understand:
• The anatomy and physiology of the thorax .
• Investigation of chest pathology.
• Surgical oncology as applied to chest surgery

3. Developmental anatomy
The lungs are derived from an out pouching of the
primitive foregut during the fourth week of
intrauterine life. This bud becomes a two-lobed
structure, the ends of which ultimately become the
lungs. The lobar arrangement is defined early and is
fairly constant but anomalies of fissures and segments
are common

4. Anatomy of the lung
The left lung is divided by the oblique fissure,
which lies nearer vertical than horizontal, so the
upper and lower lobes could also be called
anterior and posterior. On the right, the
equivalent of the upper lobe is further divided
to give the middle lobe. Each lobe is composed
of segments.

5. The bronchopulmonaryseg.
anat., fun., & surg. units of lungs.
Each lobar br., gives off seg. Bronchi.
each seg. br. enters a br. seg..
I- sup. lobe: 1) Apical,
2) Ant., & 3) post. seg.
II- Middle lobe:
1) med. & 2) lat. seg.s.
III- Inferior lobe: 1) apical,
2) med. basal, 3) lat. basal
4) ant. basal & 5) post. basal
The bronchopulmonary seg. of Rt. lung:

6. While that of Lt. lung include:
I- sup. lobe:
1) apical, 2) ant., 3) post.,
4) sup. lingular & 5) inf.
lingular.
II- inf. lobe: 1) apical,
2) med. basal, 3) lat. basal,
4) ant. basal & 5) post.
basal.

7. Tracheobronchial tree
The right main
bronchus is shorter,
wider and nearly
vertical compared with
the left. As a
consequence, inhaled
foreign bodies are
more likely to enter
the right main
bronchus than the left.

8. Mechanics of respiration
The intercostal muscles contract, causing the ribs to
move upwards and outwards, thereby increasing the
transverse and antero-posterior dimensions of the
chest wall. The diaphragm contracts simultaneously
and flattens, increasing the vertical dimension of the
chest cavity. As the volume increases, the
intrathoracic pressure falls and air flows in until the
alveolar pressure is the same.

9. Thoracic structures
•1-chest wall.
•2-pleura.
•3-lung.
•4-mediastinum.

10. Shape
•It is conical in shape
It is flattened antero-posteriorly
the floor of thorax is highly convex,domes of diaphragm,so
the volume of thoracic cavity is much less than inspection
would suggest

11. Typical ribs (3-10)
•The inferior border is sharp
and extends inferior to the
costal groove on the
internal surface of the shaft
so that it protects the
intercostal neurovascular
bundle located in the costal
groove

12. A mobile tube about 15cm long.
Has a fibro-cartilaginous wall in which a series
of U-shaped bars of hyaline cartilage are
embedded to keep lumen patent.
Commences below cricoid cartilage of larynx at
C6 body & ends in thorax at sternal angle
slightly to Rt. of midline by dividing into Rt. &
Lt. main bronchi.
Bifurcation is called carina.
Trachea:-

13. The lungs: -
Each lung lies free in its own pleural cavity,
attached only to mediastinum by its root.
has a shape of a half cone.
light, spongy in texture, & highly elastic.
Conforming to outlines of thoracic cage,
each lung has an apex & a base;
costal & med. surfaces;
& ant., inf., and post. borders.

14. Contents of lung root (HILUM) :
1- principle bronchus; transmits air
to & from lung.
2- A pulmonary artery.
3- Sup. & inf. Pul. Vv.; transmit
oxygenated bl. from lung.
4- LN & Vs.; drain lung tis. & pul.
pleura.
5- Bronchial As.; carry bl. to
bronchi.
6- Bronchial Vv.
7- Bs. of vagus n. & sympathetic
trunk; form pul. plexus that
supply all structures in lung.

15. Thoracic cavity :
Mediastinum: - a bulky septum.
Thick; root of neck - diaphragm
& from sternum to vertebral col.
relatively mobile in living subjects.
Divided by imaginary horizontal plane
sternal angle - intervertebral disc T4-5.
sup. mediastinum above this plane.
Below plane inf. mediastinum .
which is further subdivided into:
1- Ant. mediastinum lies between pericardium & sternum.
2- Middle mediastinum consists of heart in pericardial sac with phrenic Ns on each
side.
3- Post. mediastinum between pericardium ant. & vertebral col. post.

17. Lat. parts of thoracic cavity & pleura:
Pleural cavities, almost completely filled by lungs, are situated on each side of
thoracic cavity.
Each lung is covered smooth, glistening layer of pul. pleura except on hilum;
structures in root are continuous with those in mediast.
Here pul. pleura continuous with parietal, mediastinal, pleura that cover lat.
surface of mediast.
Pleura surround root of lung extend inf.
as a narrow fold known as pul lig.
connects pleura on med. surface of lung
below root to adjacent mediast. pleura.
Mediast. pleura continuous with other
parts of parietal pleura as follow:
1- Ant. & post., with costal pleura.
2- Inf., with diaphragmatic pleura.
3- Sup., with dome of pleura.

18. true
costal cartilages articulate directly with the sternum
rib 1-7
articulate indirectly with the sternum
rib 8-10
floating
do not articulate with the sternum
rib 11 &12
false
costal cartilages do not articulate directly with the sternum
rib 8-12
ribs

19. Bulges up; root of neck through sup. aperture.
Its apex reaches level of neck of 1
st
rib.
Rt. & Lt. domes separated by midline structures.
Subclavian Vs. arch over ant. surface of dome,
Art. near its highest point, V. anteroinferior
Int. thoracic art. descends on front of dome
from subclavian art. to back of 1
st
cartilage.
Between subclavian art & 1
st
cartilage ant. & dome
of pleura post.a layer of dense fascia,
suprapleural memb., spread from transverse
process of C 7 to int. margin of 1
st
rib.
Memb. may contain some m. f. (scalenus minimus)
which tighten it & help to maintain dome
despite changes in intrapleural pr.
Dome of pleura: -

20. Margins of the pleural cavity: - parietal pleural sac has: -
1- Ant.: 2 parietal sacs converge as they descend from dome post. to
sternoclavicular j. They touch each other at sternal angle,below this
remain in apposition to 4
th
cartilage.
At 4
th
cartilage ant. Margin of Lt. pleura deviates to Lt. descends post.
to 5
th
& 6
th
cartilages close to sternum That of Rt. pleura continues
its vertical descent. Each ant. margin becomes continuous with inf.
margin at level of xiphosternal joint.
2- Inf.: passes posteroinferiorly deep to 7
th
cartilage to cross 10
th
rib in
mid-axillary line. passes deep to 11
th
& 12
th
ribs reaching side of
vertebral col. at level of 12
th
thoracic vertebral spine
3- Post.: extends along vertebral col. from dome to the end of inf.
margin. Thus it is rounded in shape. inf. margin of lung does not
extend deep into costodiaphragmatic recess in quiet respiration. It
follows a course from a point lat. to xiphosternal j. to cross 8
th
rib in
mid-axillary line & reach level of 10
th
thoracic vertebral spine at
vertebral col.

21. mechanism of GAS EXCHANGE
At the cellular level, and in very simple
organisms, oxygen is provided by
simple diffusion. In more complex
organisms, a more complex delivery
system is necessary. The human
respiratory system supplies oxygen
through the combined processes of
convection (bulk flow) and diffusion.

22. The muscles of the chest wall and
the conducting airways bring large
volumes of gas into the alveolar
space. The alveolar surface, on the
order of 50 to 100 square meters,
provides a large area for diffusion
of gas into the blood.

23. FACTORS
DETERMINING GAS
EXCHANGE IN THE
NORMAL LUNG

24. Atmospheric Gases .The composition
of Earth's atmosphere is assumed to
be constant at 79% nitrogen and 21%
oxygen (dry), with a negligible amount
of carbon dioxide present (0.03%).
Atmospheric pressure varies according
to altitude and meteorologic
conditions.

25. Alveolar Gas
The partial pressure of gas in the
alveolus represents a critical
junction point in gas exchange.
Because the mammalian
respiratory system operates in a to-
and-fro fashion, blood and tissue
Po
2 approach, but can never
exceed, alveolar Po
2.

26. Diffusion Across the
Alveolar–Capillary Membrane
The alveolar–capillary membrane
is perfectly designed for diffusion,
with a combined surface area
somewhere between 50 and 100
square meters and a membrane
thickness on the order of 0.005
mm. In the normal lung.

27. ETIOLOGY AND DIAGNOSIS OF
IMPAIRED GAS EXCHANGE

28. Change in Inspired Gas
Decreased inspired Po
2 will cause a
decrease in alveolar Po
2

29. 1-Hypoventilation
Decreased ventilation disrupts the
equilibrium between gas exchange
by the lung and the tissues, causing
carbon dioxide to accumulate and
oxygen to fall.

30. 2-Diffusion Block
The flux of gas from the alveolar
space into the red blood cell
involves diffusion between
different phases and across various
membranes.

31. The following factors will result in an increased
Dlco:DLCO = (Diffusing lung capacity for carbon monoxide >30%)
-Increased distance between alveolus and red
blood cell
-Decreased total surface area
-Anemia
-Low oxygen saturation
-Decreased blood volume
-Low Cardiac Output

33. Radiographic
Evaluation of the Lungs
and Chest

34. ROUTINE EXAMINATION
Two views of the thorax are needed to provide a three-dimensional view of the chest:
posteroanterior (PA) and lateral projections.

35. COMPUTED TOMOGRAPHY

36. •Magnetic resonance (MRI)
imaging uses radio waves modified by a
magnetic field to produce images that contain
somewhat different information than that
obtained in the standard radiograph or CT
scan. Intravenous contrast is also not required.
MR imaging in the chest is particularly useful
in studying mediastinal structures. Lymph
nodes are distinguished easily from
mediastinal fat

37. FLUOROSCOPY
Air trapping is readily identified using
fluoroscopy. Limitation or absence of
diaphragmatic motion can be evaluated with
fluoroscopy when an elevated hemi diaphragm
is seen on routine chest radiography

38. SPIROMETRY
• MEASURES EXPIRATORY AIRFLOW VOLUME OVER TIME.
• ‘NORMAL’ REFERENCE VALUES ARE BASED ON AGE, GENDER, AND
HEIGHT.
Pulmonary function tests (marked variation with age, height, and sex)
FVC = Forced vital capacity 3.5–5L
FEV1 = Forced
expiratory volume
in 1 second >2.0L
FEV1 / FVC 70–80%
PEFR = Peak expiratory
fl ow rate 450–600l/min
DLCO = Diffusing lung capacity for carbon monoxide >30%

40. ENDOSCOPY
Bronchoscopy
Esophagoscopy
Mediastinoscopy
thoracoscopy

41. TTFNA :-
Trans
Thoracic
Fine
Needle
Aspiration

42. Thank
you