Final: Lecutre 22 Flashcards
Carnia
- Inside trachea at point of branching of primary bronchi
* Sensitive to irritation, produces cough relfex
Trachea
- Pseudostratified ciliated columnar epithelium with goblet cells
- Incomplete cartilaginous rings, trachealis muscles
What Bronchi branshings supply the lungs?
•Primary
Secondary bronchi branches supply?
•Lobes
Tertiary bronchi branches supply?
•Lobules
Bronchioles
- Devoid of cartilage, 1mm or less diameter
- Ciliated columnar epithelium–>simple cuboidal–>simple squamous in smaller branches
- Much smooth muscle, terminal and respiratory branches
What muscles are used for inspiration?
- Respiratory diaphragm
- External intercostal muscles
- Sternomastoids
- Serratus anterior muscles
- Scalene muscles
Expiratory muscles
- Passive at rest
* Forceful expiration: abdominal and internal intercostals
Tidal volume
•500 ml, volume of air that is inspired or expired with each breath at rest
Inspiratory reserve volume
•3000ml, volume of air that can be inspired in addition to tidal with forceful inspiration
Expiratory reserve volume
•1100 ml, additional volume of air that can be expired at end of tidal volume by forceful expiration
Residual volume
•1200 ml, volume of air remaining in lungs after forceful expiration
Vital capacity
•4600 ml, sum of all volumes that can be inspired or exhaled
Total lung capacity
•5800 ml, sum of all the volumes = vital capacity + residual volume
Inspiratory capacity
•3500 ml, sum of volumes above resting capacity = tidal volume + inspiratory reserve
Functional residual capacity
•2300 ml, sum of volumes below resting capacity = expiratory reserve volume + residual volume
Minute ventilation =
•16 breaths/minutes x 500 ml/breath = 8000 ml/min
Alveolar Ventilation
- Total volume of gases entering spaces participating in gas exchange per minute
- Breaths per minute x (tidal volume - dead space) = 5600 ml/min
Anatomic dead space consist of?
•Trachea, bronchi, and bronchioles
Physiological dead space consists of?
- Anatomic dead space + ventilated alveoli with porr or absent perfustion
- Total dead space is .15 L, Respiratory bronchioles + perfused alveoli = .35 L
Pleural pressure
- pressure of the fluid between parietal pleura and the visceral pleura
- During inspiration: -5 to -7.5 cm H2O
- During expiration: -7.5 to -5 cm H2O
Transpulmonary pressure
- difference between the alveolar pressure and the pleural pressure
- Alveolar during inspiration: 0 to -1 cm H2O, expiration 0 to +1
The extent (volume) to which lungs will expand for each unit increase in the transpulmonary pressure is?
- Compliance = increase in volume/ increase in pressure
- expressed in L per cm of water (pressure), normal 200 ml/cm H2O
- Distensibility x Vorig = Vinc/Pinc = Compliance
________ is a measure of the tendency of a hollow viscus to recoil toward its original dimensions upon removal of a distending or collapsing force
•Elastance
The most important components of surfactant are?
- Dipalmitoylphosphatidylcholine (a phospholipid)
* Surfactant apoproteins and Ca ions
Surfactant is produced by?
•Type II alveolar cells
