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Introduction
1. Cardiopulmonary system
2. Pulmonary system
2.1 Pathophysiology of pulmonary system
2.2 Auscultation and differential diagnosis of pulmonary system, lines and tubes
2.3 Understanding arterial blood gases
2.4 Interventions for pulmonary system
3. Neuromuscular system
4. Pediatrics
5. Musculoskeletal system
6. Other system
7. Non-systems
Wrapping up
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2.1 Pathophysiology of pulmonary system
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2. Pulmonary system
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Pathophysiology of pulmonary system

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External structures

  • Provide the external borders for the lungs
  • Borders comprised of:
    • Sternum
      • Provides anatomical landmarks for auscultation
    • Rib cage
      • 12 ribs and adjacent intercostal musculature assist with movement of air
      • Provide anatomical landmarks for auscultation
    • Vertebral column
      • Provides posterior border
    • Shoulder girdle
      • Provides attachment for accessory muscles to support in movement of air
Diagram of pulmonary system
Diagram of pulmonary system

Internal structures:

  • Upper airways
    • Entry point for air
    • Comprised of nose, mouth, pharynx, and larynx
  • Lower airways
    • Continue the conduction of air in which air gas exchange occurs
    • Comprised of trachea, bronchioles, alveolar ducts, and alveolar sacs
  • Internal supporting structures
    • Each lung is comprised of lobes
      • Right lobe has 10 segments
      • Left lobe has 8 segments
  • Pleura
    • Parietal pleura located on the outer surface and provides barrier to thoracic cage, diaphragm, and mediastinal border
    • Visceral pleura located on the inner surface and provides barriers to lung
External lungs
External lungs

Muscles and mechanics of ventilation

Ventilation cycle
Ventilation cycle

Primary muscles of inspiration

  • Diaphragm
    • When contracted, muscle is pulled downward- inhalation
      • Leads to protruded abdominal cavity
    • When relaxed, muscle in dome shape- exhalation
      • Takes the natural shape of lower rib cage
  • Intercostals
    • Aid in movement of rib cage
  • Accessory muscles
    • Scalenes
    • Sternocleidomastoid
    • Trapezius
    • Serratus anterior
    • Pectorals muscles

Primary muscles for exhalation

  • Passive recoil of activated inspiratory muscles
  • Accessory muscles that can be utilized during disease state or exercise
    • Quadratus lumborum
    • Abdominal muscles
    • Sections of intercostals

Mechanism of breathing

  • Inspiration
    • Activation of muscles to provide sufficient pressure gradient to allow for air to enter the lungs
    • Causes the movement of bony thorax outward
  • Exhalation
    • Passive recoil of the activated muscle to allow to leave the lungs
    • Causes the movement of bony thorax inward

Pulmonary function test - ventilation

Definitions
Tidal volume (TV)
Volume of air inhaled and exhaled during normal breathing
Inspiratory reserve volume (IRV)
Maximal volume of air that can be inhaled
Expiratory receive volume (ERV)
Maximal amount of air that can be exhaled
Residual volume (RV)
Volume of air that remains in the lungs after maximal exhalation
Inspiratory reserve capacity (IRV + TV)
The amount of air that can be inhaled beginning at normal exhalation and ending at maximal inspiration
Vital capacity (IRV + TV + ERV)
Amount of air that is moved volitionally during inhalation and exhalation;
Functional residual capacity (ERV + RV)
The amount of air left in the lungs after normal exhalation and forced exhalation
Total lung capacity (IRV + TV + ERV + RV)
Total amount of air that can be moved during normal inhalation, forced inhalation, normal exhalation, forced exhalation, and air left in lungs
Forced expiratory volume in 1 second (FEV1)
The amount of air exhaled in the first second during forced exhalation; normal is 70% within the first second
Pulmonary function tests
Pulmonary function tests

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