Anatomy and Physiology

• Upper airways - nose, pharynx, epiglottis, larynx
• Upper airways


  Transport gases to and from the lower airways
• Larynx


  Voice box
• Trachea

  
  

  Windpipe
• Epiglottis closes during eating and opens during speaking (to prevent aspiration)
• Lower Airways - trachea, bronchi, bronchioles, terminal bronchioles
• Lower airways 


  Transport gases in and out of the lungs
• Lower airways

  Mucous secretions entrap debris and cilia sweep out these from the respiratory tract.
• • Right bronchus is shorter, more vertical.
  • Left bronchus is longer, more horizontal.
• Lungs

  • right lung has 3 lobes
  • left lang has 2 lobes (to accommodate the heart)
• Pleurae 


  The protective covering of the lungs
• Outer Pleura - Parietal

  Inner Pleura - Visceral
• Respiratory Centers

  • The central chemoreceptors are found in the medulla oblongata. The main chemical stimulus for breathing is high levels of carbon dioxide in the blood.
• Respiratory Centers

  • The peripheral chemoreceptors are found in the aortic and carotid bodies. The main chemical stimulus for peripheral chemoreceptors is low oxygen levels in the blood.
• The main respiratory muscle for inspiration is the diaphragm. The main expiratory muscles are abdominal muscles.
• The thoracic cage is composed of 12 pairs of ribs bounded anteriorly by the sternum and posteriorly by the vertebrae.
• Normal Breath Sounds

  • Vesicular
  • Bronchovesicular
  • Bronchial
• Adventitious Breath Sounds

  • Crackles
  • Wheezing
  • Rhonchi
  • Stridor
  • Pleural Friction Rub
• Vesicular 


  Normal sound at the lung fields
• Vesicular: inspiration longer than expiration
• Bronchovesicular: inspiration equals expiration
• Bronchovesicular 


  Normal sounds auscultated at the mainstem bronchi
• Bronchial


  Harsh, hollow
• Bronchial 


  Auscultated at the trachea
• Bronchial: inspiration shorter than expiration
• Vesicular

  Normal sound at the lung fields
• Bronchial

  Normal sounds auscultated at the trachea
• Bronchovesicular

  Normal sounds auscultated at the mainstem bronchi
• Coarse crackles 


  popping bubbles
• Pleural Friction Rub 


  Creaking, grating
• Fine Crackles 


  hair moving through fingers
• Rhonchi


  Continuous, low pitched musical sound
• Wheezing 


  Continuous, high pitched musical sound
• Stridor


  Inspiratory musical wheeze over trachea