Lungs Flashcards
The lungs are a pair of respiratory organs situated in
Thoracic cavity
Right and left lungs are separated by
Mediastinum
What is the colour of the lungs in the young
Brown or Grey
In adults they become
Mottled black because of inhalation of carbon particles
Which lung is heavier
Right lung
Weight of lungs in males
Right 663g ( approximately 700g)
Left 583g
Weight of lungs in females
Right lung 546g
Left lung 467g
Lobes of the right lung
Superior
Middle
Inferior
What fissure seperates superior love from middle lobe
Horizontal fissure
What fissure separates the middle lobe from inferior lobe
Oblique fissure
The left lung has 2 lobes list them
Superior
Inferior
The left lung only has one fissure
Oblique fissure
The lung has 3 surfaces , list them
Costal
Medial( vertebral and mediastinal)
Diaphragmatic
The apex of the lung is located where
At the upper end of the lungs
The base of the lung rests on
The diaphragm
The lung has 3 borders they are
Anterior
Posterior
Inferior
Is the apex blunt or sharp
Blunt
Apex of lung is grooved by what artery
Subclavian artery on the medial side and anteriorly
Apex of lung is covered by
Cervical pleura (suprapleural membrane )
Diaphragm separates right lung from what
Right love of liver
Diaphragm separates left lung from
Left lobe of liver
Fundus of stomach
Spleen
Is the base concave or convex
Concave
Anterior border of left lung has a great impression, what is it called
Cardiac notch and it is below the level of 4th costal cartilage
What forms the cardiac notch
The heart that rests near the left lung
The costal surface is
Large and convex
The costal surface is in contact with what
Costal pleura and overlying thoracic wall
Inferior border separates base from
Costal and Medial surfaces
Medial surface is divided into
Vertebral surface (posterior)
Mediastinal surface (anterior)
Posterior border extends from where
Level of 7th cervical spine to 10th cervical spine
The small lobe on the left lung is called
Lingula
What covers the lungs
Pleura
Pleura is divided into
Parietal pleura (outer)
Visceral pleura(inner)
Structures related to mediastinal surface of right lung
Right atrium and auricle
Right ventricle (small part)
SVC
RIght brachiocephalic vein
Azygos vein
Oesophagus
IVC
Trachea
Right vagus nerve
Right phrenic nerve
Structures related to mediastinal surface of left lung
Left ventricle
Left auricle
Pulmonary trunk
Arch of aorta
Descending thoracic aorta
Left subclavian artery
Thoracic duct
Oesophagus
Left brachiocephalic vein
Left vagus nerve
Left phrenic nerve
Left recurrent laryngeal nerve
What is the root of lung
They are formed by structures which either enters or comes out of the lung at the hilum of the lung
Contents of the root of right lung
Eparterial bronchus (posteriorly)
Hyparterial bronchus with bronchial vessels (posteriorly )
Posterior pulmonary plexus along its posterior wall
Pulmonary artery in between two bronchi (in the middle)
Superior pulmonary vein (anteriorly)
Inferior pulmonary vein (anteriorly )
Anterior pulmonary plexus
Lymph nodes
Lymph vessels
Contents of root of left lung
Single bronchus with bronchial vessels ( posteriorly)
Post pulmonary plexus along post wall
Pulmonary artery above bronchus (in the middle)
Sup pulmonary vein anteriorly
Inf pulmonary vein anteriorly
Ant pulmonary plexus
Lymph nodes
Lymph vessels
Arterial supply to the right lung
Bronchial artery– arises 3rd right PST intercostal artery
Arterial supply to left lung
2 bronchial arteries–arises from descending thoracic aorta
Venous drainage of lungs
Bronchial veins –left and right
Left bronchial vein drains into
Accessory hemiazygos vein
Right bronchial vein drains into
Azygos vein
Explain how deoxygenated blood is brought to the lungs and how oxygenated blood is related to heart
The lungs are supplied with deoxygenated blood by the pairedpulmonary arteries. Once the blood has received oxygenation, it leaves the lungs via fourpulmonary veins(two for each lung).
What kind of anastomosis is between bronchial and pulmonary arteries
Precapillary anastomoses
The precapillary anastomoses enlarges when
Either the bronchial or pulmonary arteries is obstructed in disease
Greater part of Venous blood is drained by
Pulmonary veins
Innervation
Parasympathetic innervation from vagus nerve
Sympathetic innervation from 2nd to 5th sympathetic ganglia
Together the PSF and SF form ant and post pulmonary plexuses
What are bronchopulmonary segments
It describes the division of the lungs into segments based on the tertiary or segmental bronchi.
Bronchopulmonary segments of right lung
They are 10 in number
A – Anterior
P–Posterior
A–Anterior
L–Lateral
M–Medial
S–Medial
M–Medial
A–Anterior
L–Lateral
P– Posterior
3 are in superior lobe
2 are in middle lobe
5 are in posterior lobe
Bronchopulmonary segments of left lung
10 in number
A–Apical
P–Posterior
A–Anterior
S–Superior lingular
I–Inferior lingular
S–Superior
M–Medial basal
A–Anterior basal
L–Lateral basal
P–Posterior basal
Trachea divides at what level into 2 primary principal bronchi
At the level of the lower border of 4th thoracic vertebra
Which primary bronchi is short
Right primary bronchus (2.5cm)
Wide and short
Left principal bronchus is how many centimetres
5cm
Longer and narrower
The principal bronchus enters lung through hilum and divides into
Secondary lobar bronchi
3 on right
2 on left
Each lobar bronchus divides into
Tertiary or Segmental bronchii
Segmental bronchi divide repeatedly to form
Small branches called terminal bronchioles
Terminal bronchioles divide further into
Respiratory bronchioles
Respiratory bronchioles end in
Alveolar ducts
Atria
Air saccules
Pulmonary alveoli
Gaseous exchange takes place in
Alveoli
What divides trachea into 2 primary bronchi
Carina
Clinical questions
…
A young boy with sore throat while playing with
small coins, puts 3 coins in his mouth. When asked
by his mother, he takes out two of them, and is not
able to take out one.
•Where is the third coin likely to pass?
•What can be the dangers to the boy?
Since the boy was having sore throat, it is likely
the coin has been inhaled into his respiratory
passages. The coin would pass down the larynx,
trachea, right principal bronchus, as it is in line with
trachea. The coin further descends into lower lobe
bronchus, and into its posterior basal segment. That
segment of the lung would get blocked, causing
respiratory symptoms.
If the coin goes into oropharynx and oesophagus,
it will comfortably travel down whole of digestive
tract and would come out in the faecal matter next
day.
A 45-year-old man complained of severe cough, loss
of weight, alteration of his voice. He has been
smoking for last 25 years. Radiograph of the chest
followed by biopsy revealed bronchogenic car
cinoma in the left upper lobe of the lung.
•Where did the cancer cells metastasise?
•What caused alteration of his voice?
The bronchogenic carcinoma spreads to the
bronchomediastinal lymph nodes. The left supraclavicular nodes are also enlarged and palpable; so
these are called ‘sentinal nodes’.
The enlarged bronchomediastinal lymph nodes may exert pressure
on the left recurrent laryngeal nerve in the thorax causing alteration of voice.
The cancer of lung is
mostly due to smoking.
What is bronchial asthma
Bronchial asthma is a common disease of respiratory system.
It occurs due to bronchospasm
of smooth muscles in the wall of bronchioles.
Patient has difficulty especially during expiration.
It is accompanied by wheezing. Epinephrine, a sympathomimetic drug, relieves the symptoms.
What is the most commonest lung disease
Tuberculosis
