Respiratory Physiology Flashcards
How thin are alveolar walls?
< 1 micrometer
What are alveolar walls made of?
Simple Squamous Epithelium
What is the surface area of the alveoli?
35 times the surface area of the body
What is the bifurcation of the trachea called?
Carina
How many lobes and BP does the left lung have?
2 lobes
9 BP
How many lobes and BP does the right lung have?
3 lobes
10 BP
What do autonomics do?
Control bronchoconstriction/dilation
What does the pulmonary plexus include?
Sympathetic
Parasympathetic
Sensory innervation
What is does the Vagus nerve do?
parasympathetics
bronchocontriction
What does the sympathetic trunk do?
Sympathetics
bronchodilator
What is the role of acetylcholine in autonomics?
Pre and post-ganglionic cholinergic receptors that react to acetylcholine
What regulates respiration?
PNC Pneumotaxis center Pons
DRG/VRG Medulla
What are chemoreceptors sensitive to?
Pco2 and Po2 and pH of blood/cerebrospinal fluid
Baroreceptors role?
Blood pressure change detection
Respiratory centers influences?
Glossopharyngeal IX
Vagus X
Where are the chemoreceptors of the Glossopharyngeal nerve?
Carotid bodies
Where are the chemoreceptors of the Vagus nerve?
Aortic body
Where are the baroreceptors of the Vagus nerve?
Carotid sinus
Where are the baroreceptors of the Glossopharyngeal nerve?
Aortic Sinus
What is the Hering-Breuer reflex?
Inflation, prevents over expansion
Deflation, inhibits over expiration
What is hypercapnia?
High blood carbon dioxide
What is hypocapnia?
Low blood carbon dioxide
What are the most important respiratory muscles?
Diaphragm
External intercostal
What does the internal intercostal muscle do?
Depress the ribs
What is Boyle’s law?
Defines the relationship between gas pressure and volume P= 1/V
What is surfactant and what does it do?
Oily secretion, contains phospholipids and proteins that coat the alveoli and reduce surface tension
What are the three layers of the alveolar wall?
1 Squamous epithelium of alveolus
2 Endothelial cells of the capillary
3 Fused basal laminae between the two
How many bronchial arteries?
2 on left
1 on right
What is the blood pressure in the pulmonary circuit?
30 mm Hg
What is compliance of the lung?
Indicator of expandability, low compliance means more breathing force needed
What affects compliance?
1 Connective-tissue structure
2 Level of surfactant
3 Mobility of thoracic cage
What is atmospheric pressure at sea level?
1 atm = 760 mm Hg
What is intrapulmonary pressure?
Slightly different from Patm
+/- 1 mm Hg
What is intrapleural pressure?
-4 mm Hg Avg.
Max of -18
Has to remain below Patm to keep the lungs from collapsing
What is tidal volume?
Volume of air moved per breath
How does fetal hemoglobin differ?
Binds Hb better
What are pulmonary vessels and lungs doing before birth?
Collapsed
What is pneumothorax?
Allows air into pleural cavity
What is atelectasis?
Collapsed lung, result of pneumonia thorax
Which neurotransmitter is released by the post ganglionic neurons of the parasympathetic nervous system innervating the bronchial tubes?
acetylcholine
Which type of neurotransmitter receptor is between the post ganglionic neurons of the sympathetic nervous system and the bronchial tubes?
adrenergic
Which specific nerve carries the parasympathetics to the bronchial tubes?
vagus (or cyon)
The chemoreceptors in the carotid body send information to the brainstem via which nerve?
glossopharyngeal CN IX
The baroreceptors in the aortic body send information to the brainstem via which nerve?
vagus CN X
Which neurotransmitter receptor is between the post ganglionic neurons of the parasympathetic nervous system and the bronchial tubes?
cholinergic muscarinic
Which type of neurotransmitter is released by the post ganglionic neurons of the sympathetic nervous system and the bronchial tubes?
norepinephrine/noradrenaline
