Pulmonary Physiology and Pathology Flashcards
three most important structures of resporatory system
- lungs - gas exchange
- muscles of respiration - move air in and out.
- brain - regulates the process
structures of the rest system
upper
* larynx and above - oral cavity, nasopharynx, oropharynx
lower
* trachea and below - primary bonito, lungs
respiratory mucosa
- mucous membranes that line the respiratory tract
- protection: film of mucous that coats and protects underlying cells
- immune support: manually captures debris/traps pathogens, mucins/proteoglycans, bacterial interface
- lubricant: regurgitates stuff stuck in resp tract from aspierations
structures of rest system
nasal cavity pharynx larynx trachea bronchi bronchioles ALVEOLI (gas exchange) Lungs Pleuroa *all others are movement of air
nasal cavity
turbinates warm, moisten and filter air
- breathing through mouth makes you more susceptible to infectons
pharynx
throat, shared by rest and digestive
- naso, oro, laringo
- uvula blocks food into nasal cavity
- epiglottis blocks food into lungs
larynx
vocal chorts
- tighter = high pitch
- looser = lower pitch
trachea
wind pipe
- cartilage rings keep it open
bronchi
- right = wider
and straighter - aspirations happen on the right most of the time
alveoli
gas exchange
- surface area gives lots of areas for gas exchange
- emphysema, destroys alveoli
- SERFACTANT: decreases surface tension. keeps alveoli walls open and from sticking together
lungs
last for form in embryonic process
- right is larger, 3 lobes
- left smaller, 2 lobes
serous membranes
- around heart, lungs and GI
- higs organs, serous fluid, and lines cavity
pleura
- pa = pressure in alveoli
- pb = barometric pressure, outside the body
- pip = intrapleural pressure
- pressure gradient, air flows from high to low
- parietal (outside) and visceral (inside) with serous fluid in between
- Pa = pip –> collapsed lung
- Pb = pip –> collapsed lung
- Pip always needs to be < Pa to keeps lungs inflated. Pip needs to be negative pressure
mechanics of breathing
- alveolar surface tension - surfactant (decreases surface tension)
- elastic properties of the lung and chest wall - elastic recoil (expiration) & compliance (inhilation)
- ariway resistence
* all 4 decrease work to breathe
4 steps - mechanics of breathing
- ventilation - of lungs
- diffusion - of o2 from the alveoli into the capillary blood (air into blood)
- perfusion - of systemic capillaries with oxygenated blood (blood flow)
- diffusion - of o2 from systemic capillaries into the cells
* diffusion of co2 occurs in reverse order
Medulla and Pons
- medulla - normal rest rate
- pons - increase or decreases the rate as needed
PONS
1. apneustic center = increased inspiration - stimulates neurons to promote inspiration via external intercostals and the diagohragm
2. pneumotaxic center = increased expiration - stimualted neurons to promote expiration via the intercostals and rectus abdominous
chemoreceptors
co2
- central chemoreceptors = medulla and measure co2
- peripheral chemoreceptors = aorta and carotid bodies and increase co2
- both detect increased levels in co2 and then stimulate increase in Respiratory rate
ventilation
mechanical movement of air or gas into and out of the lungs
- minute volume = vent rate x volume of air per breath
- alveolar ventilation = how much gas exchange
conducting airways of ventilation
nasopharynx oropharynx larynx trachea bronchi bronchioles (reactive airways)
gas exchange
alveoli
- epithelial cells
1. type 1 alveolar cells = alveolar structure. where diffusion of respiratory gasses occur
2. type II alveolar cells = surfactant production - Dust cells = macrophages that live in alveoli
pulmonary circulation
pulm pressure is lower than systemic circulation
- right side of heart = less pressure
- 1/3 pulmonary vessels filled with blood at any moment
- pulmonary artery divides and entered the lung at the hilus
- each bronchus and bronchiole has an accompanying artery or ateriole
