Lecture 3: Pulmonary system Flashcards
(102 cards)
Functions of the respiratory system:
1) Gas exchange: of O2 and CO2
2) Acid-base balance: removing CO2 in body, which reduces H+ (to reduce acidity)
3) Phonation: production of sound (speech, singing)
4) Pulmonary defense: protection from bacteria, dust, toxic particles
5) Pulmonary metabolism: metabolize substrates for energy and nutrients in lungs
Phonation means
Production of sound
Consists of the nasal cavities, sinuses, pharynx, tonsils, and larynx
Upper airway
Consists of the conducting airways, including the trachea, bronchi, and bronchioles
Lower airway
Where gas exchange happens
Terminal alveoli
What are the 3 components of the right superior lobe of the lung?
1) Apical (top)
2) Posterior
3) Anterior
What are the 2 components of the middle lobe of the right lung?
Lateral
Medial
What are the 5 components of the inferior lobe of the R lung
1) Superior
2) Medial Basal
3) Anterior basal
4) Lateral basal
5) Posterior basal
What are the 4 parts of the superior lobe of the L lung?
1) Apicoposterior
2) Anterior
3) Superior lingular
4) Inferior lingular
What are the 4 parts of the inferior lobe of the left lung?
1) Anteriormedial basal/superior
2) Medial basal
3) Lateral basal
4) Posterior basal
Exchange of gas between external environment and alveoli in lungs
Alveolar ventilation
Flow of blood to the alveolar capllaries and tissues
* Both are needed for movement of O2 and CO2 and for their exchange
Perfusion
Partial pressure of O2 and CO2 in alveoli are determined by a relationship between what two variables?
Ventilation
Perfusion
What do we want our ventilation perfusion ratio to be?
As close to 1 as possible
V/Q = ventilation/perfusion
V = alveolar ventilation rate
Q = perfusion rate
What is normal alveolar ventilation?
4L/min
What is normal pulmonary blood flow?
5L/min
What is a normal ventilation perfusion ratio?
0.8
v/q = 4L/min air / 5L/min blood = 0.8
So slightly more blood than air typically, but we want this ratio as close to 1 as possible
What two things impact the V/Q ratio? (3)
Gravity
Body position
Cardiopulmonary dysfunction
When is perfusion the greatest? (what positions)
Gravity dependent area
* think lower lobes of lungs when sitting
* so more blood flow when gravity is pushing the blood down is what I think this is saying
this is why its harder to breathe when lying down than it is sitting up
V/Q mismatch = inequality in the relationship between ventilation and perfusion