Lectures 1-4 - Intro, Anatomy, MCT, Ventilation, Pleurae Flashcards
What are methods of airway clearance? (4)
•Airway clearance
- Intermittent positive pressure breathing (IPPB)
- Flutter / Acapella
- Positive expiratory pressure (PEP)
- Cough assist device
The NOSE
Function (3)
Important anatomical structures (5)
Function:
• Warming, humidifying, and filtering air.
• Resonating chamber for speech
• Houses olfactory receptors for smell
Anatomy:
Vestibule: Proximal to the nostrils, is lined with vibrissae that filter large particles from inspired air.
Pseudostratified ciliated columnar epithelium (PCCE) – Line the nasal cavity. Contain goblet cells and serous glands that produce mucus and defensins, respectively.
Mucus – Contains antibacterial enzyme lysozyme. High water content to help moisten inhaled air.
Turbinates (Conchae) – Superior, middle, and inferior projections in the lateral wall of the nasal cavity. Functions to slow down airflow to allow the air to be warmed, humidified, and filtered.
THE SINUSES
Name all 4
List their functions (4)
Paranasal Sinuses – 4 air-filled pockets surrounded the nasal cavity. • Sphenoid • Ethmoid • Frontal • Maxillary Function: • Lighten weight of the cranium • Act as resonance chambers for speech • Warm and humidify air • Produce mucus
Nasopharynx:
Location
Epithelia
Structures (2)
Nasopharynx
• Posterior to nasal cavity
• Pseudostratified ciliated epithelium for air
• Cilia inside power stroke downwards towards the larynx to initiate coughs or allow swallowing
Adenoids (pharyngeal tonsils)
• B lymphocytes here help immune function
Eustachian tube – Connects middle ear to the nasopharynx
Oropharynx:
Location:
Epithelia
Structure
Oropharynx
• Posterior to oral cavity, inferior to nasopharynx
• Stratified ciliated epithelium for air and food (needs to be tougher)
Laryngopharynx
Structure
Epithelia
Laryngopharynx
• Point of bifurcation of the common food and air passageways – trachea anteriorly, and oesophagus posteriorly.
Epiglottis – closes in the presence of food to prevent aspiration.
The Larynx
Epithelia
Structures within (2-3)
Larynx
• Anterior bifurcation from laryngopharynx
• Covered by protective epiglottis.
• Houses true vocal cords that produce speech
• Connects to trachea
• Stratified ciliated epithelium
• Cilia inside power stroke upwards towards the larynx (which is consistent all the way down to the lungs).
Vestibular folds (false vocal cords) – open and close glottis to regulate airflow for true vocal cords. Closing the glottis with external pressure creates the Valsalva manoeuvre.
TRACHEA Layers (3) Epithelia Function Structures within (2)
Structure:
Arises in larynx, and passes into the mediastinum
• 3 layer structure – mucosal, submucosal, adventitia.
Inner Mucosal ¬– Pseudostratified ciliated epithelium. Contains goblet cells
Middle Submucosal – Contains seromucus glands
Outer Adventitia – Semi-circle hoops of cartilage incomplete posteriorly.
Functions to prevent trachea collapsing during exhalation and allow bolus of food to pass posteriorly.
Trachealis - Small muscle that reinforces cartilage hoops posteriorly.
Carina – Point of bifurcation of the trachea into the two main bronchi.
The Bronchi
Location”
Composition
Structures within
Bronchi – Begins at T7 – runs obliquely down the mediastinum before entering the lungs at the hilum. Lack cartilage, but abundant in smooth muscle.
• Contraction or relaxation of smooth muscle affects caliber of the airways (resistance to airflow). Controlled by the PNS.
• Right main bronchus is slightly wider, and branches off at 20-30 degrees (more vertical, aspirated things more likely to go here). Branches into 3 lobar (secondary) bronchi.
• Left main bronchus is slightly smaller, and branches off at 45-55 degrees. Branches into 2 lobar (secondary) bronchi.
Lobar bronchi – Supply the lobes of each lung, and subdivide into segmental bronchi and bronchioles
Trachea Main Bronchus Lobar Bronchus Segmental bronchioles Terminal bronchioles Respiratory bronchioles Alveoli
Respiratory bronchioles
• Consist primarily of rudimentary alveoli and connective tissue only.
What is the difference between the conducting zone and the respiratory zone?
The conducting zone carries air from trachea–> terminal bronchioles
Respiratory zone carries air from respiratory bronchioles to alveoli.
What is the definition of respiration?
What is internal vs external respiration?
Respiration
O2 transports from the atmosphere to the body tissues, followed by the subsequent release and transportation of CO2 produced by the tissues to the atmosphere.
Respiration involves 2 processes:
• External respiration (pulmonary gas exchange
• Internal (tissue) respiration
Describe the pleura
The Pleura
• A thin-double layered serous membrane
• Parietal pleura lines the thoracic wall and diaphragm
• Visceral pleura lines the surface of the lungs and fissures
• Double layer creates pleural cavity
• Pleural fluid keeps the 2 layers locked together through surface tension.
• Intercostal and phrenic nerves innervate the pleura.
THORACIC CAGE
Structure
Function
The Thoracic Cage • Cone shaped Posterior border – thoracic vertebrae Lateral border – Ribs Anterior border – Sternum and costal cartilage Primary function: Protection Secondary function: • Movement • Support • Muscle attachment points
THE RIBS
Characteristics (5)
The Ribs
• 12 pairs
• Attach posteriorly to the thoracic vertebra
• Slope inferiorly as curve anteriorly
• True ribs = 1-7 (increase in length)
• False ribs = 8-10 (decrease in length)
• Floating ribs = 11-12 (decrease in length)
RIB joints (2) RIB MOVEMENTS (2)
Costovertebral Joint
Articulation:
Head of the rib and vertebral body level and below (ex. Rib 7 w/ T6 and T7)
Costotransverse Joint
Articulation:
• Between rib tubercle and transverse process (Rib 7 and T7 transverse process)
MOVEMENTS
Ribs 1-5 move in a pump handle fashion to increase AP diameter of thorax.
Ribs 8-10 move in a bucket handle fashion to increase lateral diameter of thorax.
