Respiratory - Physio

  1. Cyanosis
    bluish discoloration of skin/membranes due to low oxygen content of BS
  2. Pleural effusion
    accumulation of fluid in the pleural cavity, leading to difficulty w/inspiration
  3. Cause of pleural effusion
  4. Why does inflammation of the central part of diaphragm cause referred pain to the shoulders?
    supplied by phrenic nerve which also supplies to scapula
  5. Parasympathetic innervation
    M3 receptors - causes bronchoconstriction
  6. Sympathetic innervation
    beta-2 receptors - causes bronchodilation
  7. What defines a bronchiole?
    • diameter <1mm
    • alveolar sacs
  8. Respiratory zone
    • exchange of gases
    • consists of respiratory bronchioles, alveolar ducts and alveolar sacs
  9. Conducting zone
    • transports gases
    • consists of trachea, bronchi, bronchial tree
  10. What are type I pneumocytes?
    large, flat cells that form the thin gas diffusion barrier
  11. What are type II pneumocytes?
    produce surfactant to reduce alveolar surface tension and thereby prevent collapse
  12. How does gas exchange occur in the lungs?
    simple diffusion via respiratory membrane
  13. Components of the respiratory membrane
    alveolar and capillary membranes
  14. Fick's Law of Diffusion
    Rate of diffusion = (SA * Partial Pressure difference)/Distance (thickness of membrane)
  15. How does pneumonia effect diffusion?
    membrane thickness increases due to consolidation (filling of alveoli/small airways w/inflammatory exudates) and diffusion decreases
  16. How does emphysema effect gas exchange?
    there is destruction of alveoli, therefore SA is decreased, thereby diffusion of gases is decreased
  17. Dust cells (PAM - pulmonary alveolar macrophages)
    ingest particles <2 micrometers in diameter
  18. Immunity
    • secretions contain IgA to help in resisting infections
    • epithelium also contains prostaglandins protective to epithelial cells
  19. Central airways - trachea and bronchi
    have cartilaginous support - stiffer - greater air velocity - more turbulent flow
  20. Peripheral airways - bronchioles
    have smooth muscles - more compliant - parallel arrangement - lesser resistance - lower velocity - less turbulent flow
Card Set
Respiratory - Physio
Respiratory physiology notes