Respiratory Disorders Flashcards
What are the respiratory systems primary functions?
Gas exchange between atmosphere and blood, protection from inhaled pathogens and irritants, regulation of body pH, also vocalization/phonation
What structures make up the upper airways?
Nasal cavity, pharynx, larynx (above the vocal cords)
What structures make up the lower airways?
Larynx (portion below vocal cords), trachea, bronchi, bronchioles, alveoli
What is the mucociliary apparatus?
Located on larger airway portions, cilia on epithelium function to move mucus secreted by goblet cells up towards larynx to be removed
What is surfactant?
Phospholipid substance secreted by type II alveolar cells, lines alveoli to decrease surface tension, make it easier to inflate the lungs
What are the four steps of gas exchange?
Ventilation of the lungs, diffusion of oxygen from the alveoli into the capillary bed, perfusion of systemic capillaries with oxygenated blood, diffusion of oxygen from systemic capillaries into the cells
Is expiration a passive or active process?
Passive- but can become active when there is resistance or someone is trying to breathe at maximum capacity
What is the average V/Q ratio for lungs?
0.8, indicates the rate of blood flow across the alveoli is greater than the rate of ventilation
What would a high V/Q ratio indicate?
Not enough perfusion of a well-ventilated area, can occur in the apex of the lung or when pulmonary vessels are occluded
What would a low V/Q ratio indicate?
Not enough ventilation of a well-perfused area, can occur in base of lung, or with airway narrowing or obstruction
What is the role of the pulmonary aterioles?
Try to relax/constrict to direct blood to the ventilated areas
What is obstructive lung disease?
Causes difficulty on expiration, results in air trapping/dyspnea/SOB
What disorders are examples of obstructive lung disease?
Asthma, COPD, cystic fibrosis
What is restrictive lung disease?
Prevents lungs from fully expanding and interferes with proper inspiration
Which disorders are examples of restrictive lung disease?
Intrinsic (interstitial lung disease, adverse drug reaction) or extrinsic mechanisms (chest wall and neuromuscular disorders such as ALS, myasthenia gravis), interstitial lung disease (pneumonia, fibrosis, etc.) or injuries (obesity, scoliosis)
What differentiates asthma from other obstructive lung diseases?
Reversibility of obstruction (spontaneous or with treatment)
In general, what type of hypersensitivity reaction is asthma?
Type 1
Which interleukins do Th2 cells secrete in asthma?
IL-4, IL-5, IL-8, and IL-14
What is the role of IL-4?
Helps B cells differentiate into plasma cells, promotes class switching from IgG to IgE
What is the role of IL-5 in asthma?
Aids in recruitment of eosinophils
What is the role of IL-13 in asthma?
Enhances the secretion of fibroblasts, contributes to bronchoconstriction, works with IL-4 to cause IgE class switch
What type of response do Th1 cells cause?
Cell-mediated response (T cells)