Respiratory Anatomy
What is the nerve that supplies motor supply to the diaphragm?
Phrenic Nerve (C3-5).
Which type of innervation dominates control of bronchial smooth muscle in humans — sympathetic or parasympathetic?
Parasympathetic.
Name one common trigger of asthma.
⚬ Cold and flu
⚬ Cigarette smoke
⚬ Allergens: house dust, mites, mould, pollen, pets
⚬ Exercise
⚬ Weather- cold air, temperature change
⚬ Work-related triggers: wood dust, chemicals
⚬ Certain medications: aspirin
⚬ Stress and high emotions
What survives longer on surfaces, non-enveloped viruses like rhinovirus or enveloped viruses like influenza?
Non-enveloped viruses.
During inhalation, what happens as the diaphragm contracts?
The dome flattens, increasing thoracic volume.
What effect does activation of β2-adrenoceptors have on airway smooth muscle, and what normally activates them?
β2-adrenoceptor activation causes bronchodilation. These receptors are activated mainly by circulating adrenaline and noradrenaline.
What is the key inflammatory cell in atopic asthma?
Eosinophils.
Name the four layers of defence that protect the healthy airway.
Aerodynamic, chemical, mechanical, and cellular.
Which intercostal muscle is responsible for aiding inspiration?
External Intercostal Muscles.
Name the primary defence mechanism of the airways and what type of epithelium lines it.
Mucociliary Escalator.
Pseudostratified Ciliated Columnar Epithelium.
Name the T helper (Th) cell associated with atopic asthma and the three cytokines produced by it.
Th2.
IL-4/IL-5/IL-13.
What is the name of the ring of lymphoid tissue surrounding the pharyngeal entrance?
Waldeyer's Ring.
The superior thoracic aperture is bordered by which structures?
Vertebra T1, Rib I, and the Manubrium.
A patient has reduced surfactant production. What would happen to the alveolar surface tension and lung compliance?
You have a patient who is a known asthmatic. You take a sputum sample. Name at least two pathognomonic things you'd expect to observe in the microscopic image of the sample?
• Curschmann spirals
• Eosinophilia
• Charcot-Leyden crystals
Which virus is the most common cause of the common cold?
Rhinovirus.
What are the vertebral levels of the openings for the IVC, Aorta, and Eosophagus?
IVC - T8
Eosophagus - T10
Aorta - T12
You have a patient who comes in and is diagnosed with pulmonary fibrosis. What spirometry values would you expect to see?
Decreased FVC
Decreased FEV1
FEV1/FVC ratio is often normal or elevated.
Name at least four components of airway remodelling that occur in asthma.
1. Thickening of airway wall
2. Sub–basement membrane fibrosis
3. Increased vascularity
4. Increase in the size of the submucosal glands and number of airway goblet cells
5. Hypertrophy and/or hyperplasia of bronchial wall smooth muscle
What is the main role of secretory IgA in respiratory defence?
It neutralises pathogens and blocks their attachment, entry and colonisation at mucosal surfaces.