Respiratory Flashcards
Lung development
1) respiratory tract is derived from ___
2) what first branches from esophagus to form the lungs?
3) does this arise from forgot, Midgut, or hindgut
1) Endoderm
2) Ventral Bud
3) Foregut
Vascular Supply
1) which aortic arch does the pulmonary vasculature form from?
2) where do the bronchial arteries come from? What did they supply?
3) how do pre-Acenar arteries develop? When are they complete?
4) how do intra-Acenar arteries develop? When are they complete?
1) sixth aortic arch
2) aorta to the conducting airways, visceral, pleura, connective tissue
3) angiogenesis (16 weeks)
4) vasculogenesis (alveolar development to 8-10 years)
Alveolarization
1) what phase does this occur? (Timeline)
2) how many alveoli at term? Adult?
3) what enhances alveolarization?
4) what delays alveolarization?
1) alveolar phase (36 weeks to 8 years)
2) 50 – 150million -> 200–600 million
3) vitamin a and thyroxine
4) postnasal steroids, oxygen, malnutrition, ventilation, insulin, inflammation
Lung development
List the stages of lung development and gestational age
Embryonic (0–5)
pseudoglanular (5–15)
canalicular (15–25)
Sacular (25–35)
Alveolar (36+)
Embryonic
1.) structures?
2.) developmental abnormalities?
-Ventral bud, bronchi, five branches/lobes (“5 branches by 5 weeks”)
-Pulmonary vasculature from 6th aortic arch
-laryngeal cleft, tracheostenosis, tracheoesophageal fistula, bronchogenic cyst
Pseudoglandular
1) structures?
2) developmental abnormalities
Branching up to terminal bronchi
Bronchopulmonary epithelium -> amniotic fluid
Pneumocyte precursors
Vasculature (artery/veins)
Separation of thorax/peritoneal (7wk)
Branching abnormalities, CDH, CLE, CPAM, pulmonary lymphangiectasia
Cannulicular
1) structures?
2) developmental abnormalities?
-Terminal bronchioles/respiratory bronchioles
-Type two-> type one pneumocytes
-Viable lung at 25 weeks
Pulmonary hypoplasia, surfactant deficiency, alveolar capillary dysplasia
SACCULAR
1) structures?
2) developmental abnormalities?
-alveolar ducts
-Complete bronchial division
-Gas exchange = alveolar/capillary membrane
2) pulmonary hyperplasia, surfactant deficiency
ALVEOLAR
1) structures?
2) developmental abnormalities?
1) alveoli
-Microvasculature
2) surfactant deficiency, CLE, PHTN
PNEUMOCYTES
1) percent surface area of alveoli?
2) which secrete surfactant?
3) which is progenitor cell?
1) I = 90% II = 10%
2) type 2
3) type 2
FETAL LUNG FLUID
1) how much volume? Equal to what on PFT?
2) production rate near term?
3) how is Cl- transported and pulmonary epithelia?
4) what inhibits fetal lung fluid production?
1) 20–30 ML/KG; FRC
2) 4–5, ML/KG/HR
3) actively on basal side
4) Epi (delivery stress), B-adrenergic agonists
ABSORPTION OF FLF
1) prior to birth, function of respiratory epithelium changes from _____ secreting to _____ absorbing.
2) FLS decreases by ___, prenatally, ___ during active labor and ___ postnatal.
3) why is it helpful to have fluid in lungs at birth?
1) chloride, sodium
2) 1/3
3) P~T/r ⬆️ radius of airways allows for a lower pressure to overcome surface tension
SURFACTANT
1) what is the largest composition?
2) what percentage is surfactant proteins
1) 50% disaturated Phosphatidylcholine
2) 8%
SURFACTANT
1) chromosome for SP-A
2) chromosome for SP-B
3) chromosome for SP-C
4) chromosome for SP-D
1) 10
2) 2
3) 8
4) 10
SURFACTANT
1) which is the most abundant?
2) hydrophobic?
3) express last (early third trimester)
4) assist w/ tubular myelin formation?
5) promotes surface absorption of phospholipid?
6) aids in host defense?
1) SP-A
2) SP-B, C
3) SP-D
4) SP-A, B
5) SP-B, C
6) SP-A, D
SURFACTANT
1) which SP has no known mutations?
2) which homozygotes deficiency is autosomal recessive? Timeline of symptoms?
3) which is autosomal dominant? Timeline?
1) SP-A, D
2) SP-B @birth
3) SP-C months ➡️ interstitial lung disease
SURFACTANT
1) what is the most common known genetic cause of surfactant deficiency? Inheritance?
2) mechanism of action of this protein?
3) timeline?
1) ATP-binding Cassatt member A3 deficiency (ABCA3 deficiency); autosomal recessive
2) assist with transport of lipids; deficiency lacks DPPG, and PG. Decreased lamellar bodies.
3) soon after birth to childhood
SURFACTANT
1) ___ % of secreted surfactant is recycled
2) what is the turnover time?
1) 95%
2) 10 hours
SURFACTANT
what is Survanta made from and what does it contain?
Minced bovine long
SP-B and C (small amounts.)
No SP -A
SURFACTANT
What is infasurf and what does it contain?
Bovine lung lavage
SP-B, C
No SP -A
SURFACTANT
What is Curosurf made from and what does it contain?
Minced porcine lungs
SP-B, C
No SP-A
SURFACTANT
What is Alveofact made from and what does it contain?
Bovine lung lavage
SP-B, C
No SP-A
SURFACTANT
Laplace’s Law
P=2T/r
“LaPressure’s Law”
Pressure is directly proportional to ST and indirectly to radius.
CONTROL OF BREATHING
Boyles Law
P1V1=P2V2
