Lectures 1 and 2: Respiratory Flashcards
Most important muscle of inspiration
Diaphragm
Expiration, passive or active process?
Passive
% of N in air
78%
% of O2 in air
20.95%
% of CO2 in air
0.039%
PCO2
Measurement of partial pressure of CO2
PICO2
Partial pressure for inspired air
PACO2
Partial pressure for alveolar air
PaCO2
Partial pressure for systemic arterial blood
PVCO2
Partial pressure for mixed venous blood
Walls of conducting airway contain what kind of muscle?
Smooth muscle
Sympathetic adrenergic neurons activate which receptors on bronchial smooth muscle?
B2 receptors
What effect does B2 receptor activation have on bronchial smooth muscle?
Dilation and relaxation of the airways
Parasympathetic cholinergic neurons active which receptors
Muscarinic receptors
Muscarinic receptor activation leads to what action of bronchial smooth muscle?
Contraction and constriction
Respiratory zone structures are part of this group because
Lined with alveoli and participate and gas exchange
Name 3 areas of the respiratory zone
Respiratory bronchioles
Alveolar ducts
Alveolar sacs
Name components of respiratory bronchioles
Transitional structures
Have cilia and smooth muscle
But considered part of gas exchange because alveoli occasionally bud off their walls
Name components of alveolar ducts
Completely lined with alveoli
Contain no cilia and little smooth muscle
Name alveolar sac components
Lined with alveoli
Alveoli definition
Pouchlike evaginations of the walls of the respiratory bronchioles, alveolar ducts, and alveolar sacs
Exchange of oxygen and carbon dioxide between alveolar gas and pulmonary blood occur across where
Alveoli
Why are alveoli perfect for efficient gas exchange?
Thin and have large surface area for diffusion
Name 2 types of epithelial cells found in alveolar walls
Type I and Type II pneumocytes
What are Type II pneumocytes responsible for?
Synthesizing pulmonary surfactant and also regenerative capacity for Type I and II pneumocytes
What does pulmonary surfactant do?
Reduces surface tension
Name the phagocytic cells contained in the alveoli
Alveolar macrophages
Alveolar macrophage responsibility
Keep alveoli free of dust and debris, because alveoli have no cilia to perform this function
How do macrophages get rid of debris?
Mitigate to bronchioles, cilia carry debris to upper airways and the pharynx, where it can be swallowed or expectorated
What are the components of the conducting zone?
Trachea, bronchi, bronchioles
Trachea, bronchi, bronchioles: Smooth muscle?
No
Trachea, bronchi, bronchioles: Cilia?
Yes
Abnormal lung sounds
Wheezes
Rhonchi
Crackles
Tidal volume (definition and what it includes)
Normal, quiet breathing, includes volume of air that fills alveoli pls the volume of air that fills the airways
Inspiratory reserve volume
When asked to take deep breath at doctor (inspiring above tidal volume)
Expiratory reserve volume
Additional volume that can be expired below tidal volume
Residual volume
Volume of gas remaining in lungs after a maximal forced expiration
Inspiratory capacity composed of
Tidal volume + inspiratory reserve volume
Functional residual capacity composed of
Expiratory reserve volume + residual volume
Vital capacity composed of
Inspiratory capacity + expiratory reserve volume
Vital capacity definition
The volume that can be expired after maximal inspiration
Total lung capacity composed of
All lung volumes, vital capacity + residual volume
Dead space
Volume of the airways and lungs that does not participate in gas exchange
Anatomical dead space: what is included
Volume of conducting airways including the nose and/or mouth, trachea, bronchi, bronchioles
Anatomical dead space: Not included
Respiratory bronchioles and alveoli
Physiologic dead space definition
Total volume of the lungs that does not participate in gasexchange
What is included in physiologic dead space
Anatomic dead space of the conducting airways plus a functional dead space in the alveoli
ectWhy would alveoli not participate in gas exchange?
Usually a ventilation/perfusion defect
