1&2 Anatomy of the Respiratory System Flashcards
Where would you find the upper respiratory tract and what does it consist of?
Nostrils–> lower border of _cricoid cartilag_e of larynx
Contains:
- Nose
- Paranasal sinuses
- Pharynx (acts as 3 way valve)
- Larynx
The nasal cavity contains 4 paranasal sinuses. Identify the names of them on the following diagram:
- Frontal sinus
- Ethmoid sinuses
- Spenoid simuses
- Maxillary sinuses
What type of epithelial cells line the sinuses?
Pseudo stratified ciliated columnar epithelium
What is the function of vascular mucosa lining the paranasal sinuses (and turbinates)?
Warm and moiste air
What is the glottis?
Vocal cords and aperture between cords in larynx (connects pharynx to trachea)
Vocal cords aka vocal folds, vocal ligaments
How is the entrance to the trachea closed off during swallowing?
Laryngeal inlet narrows, epiglottis folds down- like lid
Suprahyoids lift larynx- close of trachea
Vocal cords adduct
Which muscles cause the vocal cords to move and what are they innervated by?
Intrinsic laryngeal muscles
Recurrent laryngeal nerve
Why does intra thoracic disease sometimes cause a hoarse voice?
(eg aortic aneurysm)
Recurrent laryngeal nerve on LEFT has long course- down into thoracic cavity
Nerve= compressed or infiltated
Paralysis of left vocal cord= hoarse voice
If the larynx and vocal cords are dysfunctional, what might there be an increased risk of?
Food and liquid aspiration (inhalation)
Trachea may not be properly closed off
What is the cough reflex and what is its function?
What?:
Ability to close vocal cords- build up intrathoracic pressure
Then sudden opening of vocal cords- air expelled quickly
Function?:
Protective mechanism–> expel inhaled particles
Clearance mechanism for excessive secretions
What components make up the ‘bony thorax’?
Sternum
Ribs
Thoracic vertebrae
Costovertebral joints
Rib movements
Which costal cartilage (rib) articulates with the sternum at the level of the sternal angle?
2nd
What forms the floor of the thoracic cavity?
Diaphragm
How many joints do thoracic vertebrae have?
12
Fill in the missing labels on the ‘typical’ rib (3-9)
Name the 3 muscles contained in the intercostal space, superficial to deep.
External intercostals
Internal intercostals
Innermost intercostals
Describe the external intercostal muscles and the movement they create.
Fibres run downwards and anteriorly
Responsible for 30% of chest expansion during QUIET RESPIRATION
Bucket handle movement
Describe the internal intercostal muscles.
Run downwards and posteriorly
Pull ribs down from postive chest expansion
Forced expiration
(Innermost intercostal muscles- similar to internal, act along them)
Which muscle is responsible for >70% of chest expansion in quiet respiration?
Diaphragm
The peripheral muscular fibres of the diaphragm arise from the lower margin of the thoracic cavity. What makes up the lower margin of the thoracic cavity?
- Inner aspect of xiphisternum
- Inner aspect of 7-12 costal cartilages
- Arcuate ligaments
- Crura of diaphragm
The diaphragm is innervated by which nerves?
Right and left phrenic nerves (C3,4,5)
If one of the phrenic nerves is damaged, how with the chest x-ray appear?
Elevated hemidiaphragm on affected side
At which spinal level does the diaphragm have openings for:
- Vena cava
- Oesophagus
- Aortic Hiatus
- Vena cava T8
- Oesophagus T10
- Aortic Hiatus T12
(count letters)
Where do the left and right domes of the diaphragm lie? (vertically)
Right: 5th Rib
Left: 5th Intercostal space
What is the costodiaphragmatic recess?
Peripheral gutter around edge of diaphragm
Space where lungs don’t fill thoracic cavity
How do the bronchi divide to eventually form bronchioles?
Where does the trachea begin and where does it end (divides into right and left main bronchi)?
Begins: Lower border of cricoid cartilage (of larynx) (C6)
Ends: Sternal angle (T4/T5)
What is the angle between the right and left bronchi known as?
Carina
What is a bronchopulmonary segment?
(important clinically: can be removed without much bleeding, air leakage or interfering other segments)
Area of lung supplied by:
- segmental bronchus
- accompanying branch of pulmonary artery
- drained by segmental pulmonary vein
=pyramid shaped, apex faces towards segmental bronchus
What parts of the respiratory system can be viewed when a bronchoscopy is done?
(used in diagnosis of bronchial carcinoma)
- Inner trachea
- Carina
- Main bronchu
- Lobar bronchi
- Origin of segmented bronchi
What is the conducting zone? (with relation to the lungs)
Zone between trachea and alveolar sacs where no gas exchange takes place
Conducting zone: divisions 1-16
Airway divides 23 times between trachea and alveoli
What is the respiratory zone?
Part of airway from trachea to alveoli where gas exchange occurs
Divisions 17-23 (out of 23)
Made up of:
- Respiratory bronchioles- have occasional alveoli
- Alveolar ducts
Describe the division of the lobes of the lungs.
LEFT LUNG: 2 lobes
Upper
Oblique fissure
Lower
RIGHT LUNG: 3 lobes
Upper
Horizontal fissure
Middle
Oblique fissure
Lower
Why is it that tumours of the apex of the lung can cause neurological and vascular problems in the upper limb?
Apex extends above level of 1st rib in neck
Apex closely related to subclavian vessels and brachial plexus
What is a pneumothorax?
Air leaks into pleural cavity
(eg caused by stab wound to lower neck/cannulation of subclavian vein)
On which surface of the lung can the hilum be found?
Mediastinal surface
What passes through the hilum of the lung?
- Main bronchi
- Branches of pulmonary artery
- Pulmonary veins
- Lymphatics
- Pulmonary plexuses
The mediastinal surfaces of the lung lie adjacent to important structures within the mediastinum. What are these structures?
Left (6)
Right (6)
Left
- Heart
- Aortic arch
- Descending aorta
- Oesophagus
-
Nerves
- Phrenic
-
Vagus
- Recurrent laryngeal branches (curves around arch of aorta- return to larynx)
- Sympathetic trunk
Right
- Superior vena cava
- Azygous vein
- Right atrium
- Oesophagus
-
Nerves
- Phrenic
- Vagus
- Sympathetic trunk
Italics if same L&R
The lungs have a dual blood supply: the bronchial arteries and the pulmonary arteries. Where do each of these arteries supply blood to?
Bronchial arteries
Blood from LEFT heart
Supplies: Bronchial tree and Viceral pleura
Pulmonary arteries
Blood from RIGHT heart - entire output of right ventricle- for gas exchange
Supplies: Aveoli
What is the lung parenchyma?
Portion of the lungs involved in gas exchange. The most prominent structure in this region is the alveolus
How does the majority of the blood from the lungs return to the heart. How else does blood return to the heart?
- Via pulmonary veins to left heart
- Via brochial veins drain via AZYGOUS VEIN into superior vena cava
In some patients with a pulmonary embolism, blood supply to the alveoli can be maintained. How is this possible?
There are some anastamoses between the bronchial and pulmonary arteries at precapillary and capillary level
Describe the route taken by the pulmonary veins.
DO NOT closely follow bronchi
2 pulmonary veins- leave each hilum- draining upper and lower lobes
Run in intersegmental septa
Describe the lymphatic drainage of the lungs.
(where do they drain to)
Drain to:
- Hilar nodes (bronchopulmonary nodes)
- Tracheobronchial nodes
The enlargement of which lymph nodes can cause the widening of the (angle of) carina?
Tracheobronchial nodes
Describe the nerve supply to the lungs in terms of:
- Vagus nerves (R&L)
- Sympathetic trunk
-
Vagus nerves
- Parasympathetic efferent fibres
- Motor to bronchial smooth muscle (bronchoconstrictor)
- Secretomotor to mucous glands
- Vagal afferent fibres
- Cough reflex
- Some subserving pain
- Parasympathetic efferent fibres
-
Sympathetic trunk
- Bronchodilator
- Vasoconstrictor
To identify where the oblique fissure of the lung runs in a patient, what landmarks can we use?
Extends from:
Spinous process T2
to
6th costal cartilage
To identify where the horizontal fissure of the lung runs in a patient, what landmarks can we use?
(Only on right side)
Extends from:
Mid axillary line anteriorly
along 4th rib to
anterior edge of lung
Where does the lower edge of the lung lie? Where does the pleural cavity therefore extend to?
In:
- Mid clavicular line
- Mid axillary line
- Scapular line
Lungs
- Mid clavicular line- Rib 6
- Mid axillary line- Rib 8
- Scapular line- Rib 10
Pleural cavity lies 2 ribs lower
(Diaphragm lies at 5th rib on right and 5th intercostal space on left)
Identify which area of the lung is being examined in the following images:
Upon percussion of areas of the thorax, how does the liver sound compared to the lung?
Liver sounds dull
From 5th intercostal space downwards
In condition eg COPD, lungs= overinflated
-dullness= below 5th
Why should a needle/tube be inserted into the upper border of the rib?
Avoid damaging the neurovascular bundle in costal groove
If a patient is in the upright position and and has a pleural effusion, where will the fluid collect?
Costo-diaphragmatic space
Where does the respiratory system develop from?
Outpouch of primitive gut tube
Why is the cartilage in the trachea horse shoe shaped?
Better for swallowing- space for oesophagus
What are the nerve roots for innervation of the diaphragm?
C3, 4, 5 keep the diaphragm alive
Phrenic nerves from cervical plexus
(motor and sensory to pericardium too)
Which muscles is this lady using to aid ventilation?
Pectoral muscles
Which muscles is this man using to aid ventilation?
Sternocleidomastoid
What does azygous mean (azygos vein)?
Vein= unpaired to artery
Which lung is an inhaled foreign body most likely to end up in?
With what rib does the horizontal fissure in the lung correspond with?
4th rib
Where would you oscultate the lower lobe of the right lung?
Posteriorly and to the side
Why do you need to do an x-ray of the lung following the insertion of a line into the subclavian vein?
Check lung hasn’t been punctured (apex of lung)
At what anatomical landmark does the trachea bifurcate?
At angle of louis
When percusing during a respiratory examination, in which intercostal space would you start to hear dullness (due to the presence of the liver on the right)? Where would the dullness be heard if the patient has COPD?
4th intercostal space
Dullness heard lower down in COPD
Why is the diaphragm on an x-ray found at the level of the 6th rib?
Patient asked to breath in
Diaphragm flattened- so lower down
What innnervates the diaphragm?
Phrenic nerve C3,4,5 keeps the diaphragm alive
When would you use your internal intercostal muscles?
Forced expiration
(quiet expiration is passive process)
What keeps the lungs against the thoracic wall?
Pleural seal
Whats the difference between atelectasis and a pneumothorax?
