Respiratory system Flashcards
What does the upper respiratory tract consist of
Larynx, Nasal Passages, Pharynx
What does the Nasal passages consist of
Nasal vestibule, Nasal cavities
Nasal mucosa
- nasal vestibule (skin/hair) (vibrissae)
- Respiratory epithelium (lateral walls)
- olfactory epithelium (roof)
What does the pharynx consist of
Nasopharynx, Oropharynx, Laryngopharynx
Subglottis, glottis, epiglottis
What does the respiratory epithelium have
Respiratory epithelium has Pseudostratified Ciliated Columnar with Goblet cells
What is the purpose of turbinates/conchae
Reduces airflow to enable air conditioning and filtering
What part helps to warm the air
Sub-mucous vessels
What are the cells in the mucous membrane
Goblet cells - secrete mucus
Ciliated cells - move mucus
Sensory cells - sneeze, cough
What is the main function of the larynx
Prevent asphyxiation (choking)
Which part separates airflow and food channels
Epiglottis
What does the larynx consist of
Thyroid and cricoid cartilages bound the cavity
Cartilaginous assembly by ligament and membranes
Muscles to abduct and adduct for voice production
What does the lower respiratory tract consist of
Cricoid cartilage (C6) to Sternal angle (T4)
Smooth muscle (trachealis), tracheal cartilage, respiratory epithelium, mucous glands, lamina propria
Key landmarks of lower respiratory tract
Esophagus
Left recurrent laryngeal nerve
Left vagus nerve
Arch of aorta
What is the carina
Tracheal bifurcation between separating right and left bronchi
What is the difference between right and left lung
Right lung compared to left lung is
- more vertical
- wider in diameter
- shorter in length
Foreign bodies more likely to be aspirated into right side
What innervates the bronchial tree
Mainly autonomous nerves
- sympathetic involved in increasing airway diameter (bronchodilation)
- parasympathetic involved in decreasing airway diameter (bronchoconstriction)
What supplies blood to the bronchial tree
Bronchial arteries branching from thoracic aorta
Bronchial veins draining from azygos system of veins
What are the 2 zones in the functional division
Conducting zone and respiratory zone
Where does the respiratory zone begin
Respiratory bronchioles to alveoli
Where does the conducting zone begin
Nose to terminal bronchioles
What happens in the conducting zone
No gas exchange occurs = anatomical dead zone (150mL)
Primary source of airway resistance which is greater for people with asthma
What is the respiratory zone known as
Acinus
What happens at the respiratory zone
Gas exchange
Where is the pulmonary arteries in the lungs
RALS: Right anterior, Left Superior with reference to bronchus
How many lobes does the right and left lung have
3 lobes in the right lung
2 lobes in the left lung
How many fissures are in the right and left lung
Horizontal and oblique fissure - right lung
oblique fissure - left lung
Where is the cardiac notch and lingula
Anterior of Left lung
What innervates the diaphragm
Phrenic nerves
Origin: Cervical spinal segment (C3, 4, 5)
What are the muscles involved in forced expiration
Internal intercostal
Innermost intercostal
External oblique
Internal oblique
Transversus abdominis
Rectus abdominis
What are the accessory inspiratory muscles
Levator costanum
Erector spinae
Scalene muscles
Sternocleidomastoid
Serratus anterior
Pectoralis major
What muscles are involved in inspiration
Diaphragm and external intercostal
What are the 2 movements of the chest wall for respiration
Pump handle and bucket handle motion
What happens during the ‘pump handle’ motion of the chest wall
increase in anterior to posterior diameter
forward movement of sternal body at manubriosternal joint
involves 2nd - 5th ribs mainly; 1st rib is fixed
increased anteroposterior diameter of thoracic cavity
what happens at the bucket handle motion of the chest wall
increase in transverse diameter of cavity
elevates 6 - 10 ribs at costovertebral and sternocostal joints
What are the 2 intercostal muscles
External and internal intercostal
what is the function of internal intercostal
stiffen chest wall
depress ribs in forced expiration
what is the function of external intercoastal
elevates ribs during inspiration
stiffen chest wall
Why is the diaphragm the principal muscle of inspiration
Causes descent of domes sufficient for quiet inspiration
What are the key relations of the right lung
Superior vena cava
inferior vena cava
heart
subclavian vein
subclavian artery
esophagus
azygos vein
what are the key relations of the left lung
thoracic aorta
left subclavian artery
left brachiocephalic vein
aortic arch
heart
How many brachopulmonary segments are there in each lung
10
What makes the bronchopulmonary segment an independent structural and functional unit
Has its own bronchus (air supply) and artery (blood supply)
What are the 5 types of cells in the alveoli
Type I pneumocyte (40%)
Type II pneumocyte (60%)
Interstitial cells - fibroblast and mast cells
Capillary endothelial cells
Alveolar macrophages
What is the difference between Type I and II pneumocytes
Type I
- 40% of cells in alveolus
- simple squamous epithelium
- involved in gas exchange
Type II
- 60% of cells in alveolus
- produces surfactant which helps lower surface tension in alveoli to prevent collapse
What does a lack of surfactant cause
Respiratory distress syndrome which is seen in premature babies
What is the downstream flow of each BP segment
Segmental bronchus > bronchioles > several generations > terminal bronchioles > respiratory bronchioles > alveoli ducts, sacs and alveoli
Size decreases whereas Surface area increases as we go downstream
Changes along wall of trachobranchial tree
Pseudostratification disappears
Decrease in cell height
Disappearance of goblet cells
What is pleura effusion
Excess of pleural fluid > 15mL
Causes positive intrapleural pressure which decreases lung expansion and thus blunted costophrenic angle
What is pleura cavity
In between visceral and parietal pleura which contains thin film of pleural fluid of 5 - 15mL
Plasma filtered from capillaries
What is the intrapleural pressure
756 mmHg
What is the intra-alveolar pressure
760mmHg
How does breathing occur with reference to pressure present
Diaphragm contracts and chest wall expands which results in negative intrapleural pressure which results in intra-alveolar pressure and thus inspiration occurs
Pneumothorax and chest wall injury
Causes present of air in pleural cavity and hence positive intrapleural pressure
Shifts trachea and mediastinal structures to opposite sides. Along with collapsed lung, it causes decreased alveolar ventilation
Thoracic wall skeletal parts
Associated ligaments
Costal cartilages
Sternum
Vertebrae
Ribs
Thoracic wall musculoaponeurotic parts
Diaphragm, Fasciae, Suprapleural membrane, intercostal muscles
Key landmark lines of thoracic wall
Midclavicular line
Axillary lines (anterior, middle, posterior)
Scapular lines
What are the 3 main holes in the diaphragm
Aortic hiatus
Esophageal hiatus
Caval opening (vein opening)
What are the atypical ribs
1, 11, 12
