Pulm physiology 1 Flashcards
What is the difference between ventilation and respiration?
Ventilation: movement of air going in and out.
Respiration: cellular metabolism, byproduct/removal of metabolism is CO2
What are the 4 processes that supply the body with O2 and dispose of CO2?
- Pulmonary ventilation (air in and out)
- External respiration (gas exchange at lungs)
- Transport in systemic circulation
- Internal respiration (gas exchange in the tissues)
What are the three zones of the respiratory system and what happens at each?
Conducting zone: “dead space,” just a highway to get gas in and out. Does NOT participate in gas exchange.
*nose, sinuses, and pharynx
Respiratory Zone: site of gas exchange
Respiratory Muscles: promote ventilation.
Name all of your tonsils and where they are located.
Nasopharynx: adenoids
Oropharynx: palantine, lingual
What level of the spine does the trachea bifurcate?
If a person were to aspirate into their lungs which lung is most likely going to collect this fluid?
- bifurcates at T7
- the right main stem bronchus is more vertical, the left main stem bronchus has a sharp angle.
explain the branching system of the lung.
trachea
- right and left main stem bronchi(1ry)
- lobar bronchi(right-3 left-2)(2ndry)(supply each lobe)
- segmental bronchi(3ry)
- bronchioles
- terminal bronchioles
- alveoli
what is the purpose of the smooth muscle around the bronchioles? Elastic fibers on the alveoli?
- Bronchioles: smooth muscle constricts and dilates.
- Elastic fibers maintain compliance, help facilitate air moving in and out.
What structural changes occur as you move downt he bronchial tree?
- cartilage rings diminish
- epithelium changes; cilia and goblet cells are sparse (cleaning crew is mfs and lysosomal proteins)
- smooth muscle decreases
- alveoli composed of single layer of cells, very thin.
What types of cells do you find in alveoli?
- Type 1: squamous epithelial cells
- Type 2: surfactant secreting & antimicrobial protein (lysozymes)secreting
- Mfs
- RBC of capillary
- alveolar pores
Alveoli functions
alveolar pores connect adjacent alveoli
allow air pressure through the lung to be equalized
house mf to keep sterile
gas exchange
Root aka?
hilum! :)
Explain why a wedge resection of the lungs works?
- each segment of the lung has its own blood supply, if you were to do a “wedge resection” you could take one segment of a lobe while maintaining adequate blood supply thereby not damaging any of the adjacent alveoli.
ex. like cutting broccoli
Pulmonary circulation
- describe the pressure and volume
- what kind of blood do the pulmonary arteries and veins carry?
-low pressure, high volume
- pulmonary arteries: systemic venous blood to the lungs
- pulmonary veins: oxygenated blood to the heart.
Systemic circulation
-describe pressure and volume
-high pressure, low volume
What is the pleura?
- thin, double layered serosa
- parietal(thoracic wall) and visceral(lung) pleura
- provides lubrication and surface tension
Describe the innervation of the lungs?
- Parasypathetic= constriction of bronchioles
- sympathetic=dilation of bronchioles
- they work in concert.
Pulmonary ventilation consists of two phases, what are those?
- inspiration: gases flow into the lungs
- expiration: gases exit the lungs
respiratory pressures are described relative to _____.
-atmospheric pressure
negative resp pressure is less than Patm
positive resp pressure is greater than Patm
Zero resp pressure is = Patm.
What is intrapulmonary pressure?
- it is the pressure inside the alveoli that always equalizes with Patm.
What is intrapleural pressure?
What are the forces of intrapleural pressure and how do they work?
-the pressure in the pleural cavity, always negative pressure in relation to atmospheric pressure.
- Two inward forces promote lung collapse
1. ) elastic recoil
2. ) surface tension - one outward force enlarges the lungs
1. ) elasticity of the chest wall pulls the thorax outward.
Which pressure keeps the lungs open?
- transpulmonary pressure.
- the greater the transpulmonary pressure, the larger the lungs.
What happens if Intrapulmonary and intrapleural pressure are equal?
-you have zero transpulmonary pressure, meaning your lungs will collapse.
What happens if the integrity of the pleura is compromised?
-lung collapse, results in equalization of the intrapleural pressure with the intrapulmonary pressure resulting in zero transpulmonary pressure.
Atelectasis
- aka
- cause
aka- lung collapse
cause:
-lack of air delivery d/t plugged bronchioles leading to collapse of alveoli… this it a ventilation problem such as an infection
-lack of integrity of the pleura from a wound that allows air entry into pleural cavity …this is a pleural problem such as a pneumothorax or pleural effusion
Inspiration and expiration are mechanical processes that depend on changes to produce pulmonary ventilation. Explain these changes.
mechanically the body changes the volume which changes the pressure. As the pressure changes, gasses flow to equalize the pressure and produce ventilation
What is boyles law?
pressure is inversely related to volume.
as volume increases pressure decreases.
what are three physical factors influencing pulmonary ventilation that inspiratory muscles must overcome?
-airway resistance: usually insignificant d/t large airway diameter, cross sectional surface area, and alveolar gas diffusion.
- alveolar surface tension
- lung compliance
Which part of the bronchial tree has the greatest and least amount of resistance?
- greatest: medium sized bronchi
- least: terminal bronchioles: there are MANY of them increasing the surface area.
what are three forces at work that increase airway resistance?
- bronchospasm
- mucosal edema
- secretions
name 4 conditions with increased airway resistance?
- COPD (emphysema/chronic bronchitis)
- asthma
- cystic fibrosis
- sleep apnea (upper airway resistance)
what is the purpose of surfactant?
-reduces alveolar fluid surface tension, discourages alveolar collapse
what is lung compliance?
-a measure of the change in lung volume that occurs with a given change in transpulmonary pressure.
- higher compliance = easier to expand the lungs.
- usually high d/t distensibility(stretchy), thoracic cage expansion, reduction of alveolar surface tension 2ndry to surfactant
List conditions that lead to decreased lung compliance.
- non-elastic scar tissue
- reduced production of surfactant
- decreased flexibility of thoracic cage
- deformities of thorax
- ossification of costal cartilage
- paralysis of intercostal muscles
