RCP 110 Anatomy and Physiology Exam I Study Guide

Upper Airways

• Primary components: nose, oral cavity, larynx, pharynx; essential for speech, smell, humidifying, and temperature control of inhaled air.
• Nasal flaring indicates respiratory distress, linked to conditions like asthma and pneumonia, which increase airway resistance.
• Improper endotracheal tube positioning can result in esophageal placement instead of the trachea.
• The epiglottis prevents aspiration of food and liquids by covering the trachea during swallowing.
• The larynx functions as an airway passage, prevents aspiration, and generates speech sounds.
• Post-extubation laryngeal edema treatment: aerosolized racemic epinephrine, high humidity, voice rest, and cough medications.
• Croup is a viral infection causing inflammation of the trachea and larynx; epiglottitis is a bacterial infection causing epiglottis swelling and airway obstruction.

Lower Airways

• Patients should not suppress the cough reflex, crucial for clearing secretions if the mucociliary mechanism is compromised.
• Respiratory therapies include chest physiotherapy, flutter valves, breathing exercises, and suctioning to aid secretion mobilization.
• Three layers of the tracheobronchial tree: epithelial, lamina propria, cartilaginous layer.
• Lamina propria contains mast cells that release mediators affecting bronchial airway diameter.
• Mucous blanket layers:
  • Gel layer: viscous, near lumen surface.
  • Sol layer: thinner, adjacent to epithelial lining.
• Cilia are absent in terminal bronchioles (16th to 19th generations).
• Factors impairing mucociliary transport: cigarette smoke, dehydration, positive pressure ventilation, endotracheal suctioning, high FiO2 levels.
• The cartilaginous airways are referred to as the conducting zone.
• Right lung has 10 segmental bronchi; left lung has 8 segments.
• Non-cartilaginous airways include bronchioles and terminal bronchioles.
• Bronchial arteries nourish lung structures, including the tracheobronchial tree and parts of the pleura and esophagus.
• Types of alveolar cells:
  • Type 1 pneumocytes: 95% surface area, non-reproducible.
  • Type 2 pneumocytes: produce surfactant and can replicate.
  • Type 3 alveolar macrophages: eliminate pathogens.

Key Structures and Measurements

• Endotracheal tube should sit 2-5 cm above the carina of the trachea.
• Carina: cartilage junction at the lowest trachea, separating the bronchi.

Lymphatic, Vascular, Pleura

• Stimulation of beta-2 receptors leads to bronchodilation via airway muscle relaxation.
• Accessory muscles of inspiration: scalene, sternocleidomastoid, external intercostals, trapezius; expiration: abdominal muscles, internal intercostals.
• Differences between pulmonary and systemic circulation:
  • Pulmonary: heart to lungs (oxygen uptake, CO2 release); returns oxygenated blood to the heart.
  • Systemic: heart to body (oxygen delivery, CO2 collection); returns deoxygenated blood to the heart.
• Elastance reflects lung stiffness; high elastance denotes low compliance (difficult to inflate), while low elastance indicates high compliance (easier to expand).

Ventilation and Pressures

• Ventilation: gas exchange between the external environment and alveoli.
• Barometric pressure at sea level: 760 mm Hg or 1033 cm H2O.
• Pressure changes during respiratory phases:
  • Inspiration: pressure decreases; diaphragm descends.
  • End-inspiration: pressures stabilize; diaphragm movement halts.
  • Expiration: pressure increases; diaphragm ascends.
  • End-expiration: pressure stabilizes; diaphragm movement stops.

Tension Pneumothorax

• Physiologic response: increased heart rate, decreased breath sounds, tracheal deviation, diminished cardiac output, decreased blood pressure, and confusion.

Surface Tension and Surfactant

• Surface tension defined as the resistance of a liquid surface, modified by surfactant produced by type II pneumocytes.
• Surfactant deficiency conditions include infant respiratory distress syndrome and atelectasis.
• LaPlace's Law: describes the relationship between surface tension and radius in maintaining distending pressure within liquid spheres in the lungs.

Labeling

• Able to identify the visceral pleura, parietal pleura, and pleural cavity/space as part of lung anatomy.