Respiratory Anatomy Flashcards
Conducting zone goes down to…
terminal bronchioles
“Anatomic Dead Space”
Conducting zone - warms, humidifies, and filters air but does not participate in gas exchange
Cartilage and goblet cells extend to….
end of bronchi
Pseudostratified ciliated columnar cells extend to
beginning of terminal bronchioles
Cuboidal cells begin at
terminal bronchioles
Airway smooth muscle extend to
end of terminal bronchioles
Respiratory zone consists of:
respiratory bronchioles, alveolar ducts, and alveoli
Participates in gas exchange
Respiratory zone
Cell type in respiratory bronchioles
cuboidal cells
Cell type in alveoli
simple squamous
Clear debris and participate in immune response
Alveolar macrophages
Type I Pneumocytes:
97% of alveolar surface. Squamous, line alveoli, optimal for gas diffusion
Type II Pneumocytes:
Secrete pulmonary surfactant (lecithin)
Cuboidal, clustered.
Serve as precursors to type I cells and other type II cells. Proliferate during lung damage.
Club (Clara) cells
Nonciliated; low-columnar/cuboidal with secretory granules.
Secrete component of surfactant; degrade toxins; act as reserve cells.
Collapsing pressure (P) =
P = 2 (surface tension) / radius
Surfactant (purpose)
Decreases alveolar surface tension and prevents alveolar collapse (atelectasis).
Surfactant (properties)
Complex mix of lecithins, most important of which is dipalmitoylphosphatidylcholine.
Dipalmitoylphosphatidylcholine
Most important lecithin in surfactant
La Place’s Law
Alveoli have increased tendency to collapse on expiration as radius decreases
Fetal surfactant synthesis begins at
26 weeks gestation
Fetal surfactant levels are mature at
35 weeks gestation
Fetal lung maturity is indicated by:
Lecithin-to-sphingomyelin ratio >2.0 in amniotic fluid
Right lung has how many lobes?
3
Left lung has how many lobes?
2
Left has Less Lobes and Lingula (homologue of right middle lobe)
Instead of middle lobe, left lung has space occupied by heart.
Which lung is more common site for inhaled foreign body?
Right
Right main bronchus is wider and more vertical than the left
Aspirate a peanut:
While upright - where does it go?
Lower portion of right inferior lobe
Aspirate a peanut:
While supine - where does it go?
Superior portion of right inferior lobe
Relationship of pulmonary artery to bronchus at each lung hilus:
RALS Right Anterior (pulmonary artery is anterior to bronchus) Left Superior (pulmonary artery is superior to bronchus)
Fissures of Right lung:
Horizontal fissure (separates superior and middle lobes) Oblique fissure (separates middle lobe and inferior lobe anteriorly, inferior and superior lobes posteriorly)
Fissures of Left lung:
Obliqure fissure (separates Superior and Inferior lobes)
Inferior Vena Cava perforates diaphragm at what level?
T8
Esophagus perforates diaphragm at what level?
T10
Vagus nerve perforates diaphragm at what level?
T10 (with esophagus)
CN10; 2 trunks
Aorta perforates diaphragm at what level?
T12
Thoracic duct perforates diaphragm at what level?
T12
Azygos vein perforates diaphragm at what level?
T12
What structures perforate the diaphragm at T12?
aorta (red), throcic duct (white), and azygos vein (blue)
“At T-1-2 it’s the red, white, and blue”
What structures perforate the diaphragm at T10?
Esophagus and Vagus nerve (CN 10)
Diaphragm is innervated by
C 3, 4, and 5 (phrenic nerve)
Pain from diaphragm irritation can be referred to:
shoulder (C5) trapezius ridge (C3, 4)
Common carotid bifurcates at
C4
Trachea bifurcates at
T4
Abdominal aorta bifurcates at
L4
