Respiratory 2 Flashcards
Pulmonary circulation has _____ pressures than systemic circulation
Lower
Pulmonary circulation has _____ resistance,
Lower
Pulmonary circulation has ______ compliance than systemic circulation
higher
Pulmonary circulation has _____ volume than systemic circulation
Lower
Do structures in the respiratory zone receive oxygen from bronchial flow?
No; directly from alveolar air
T/F: There are a population of pulmonary capillaries at rest
True
Diameters of pulmonary arteries and arterioles are _____ than systemic arteries and arterioles
larger
Bronchial flow is about ___% of cardiac output of the left ventricle.
2%
Supplies oxygen and nutrients to the tracheobronchial tree down to the terminal bronchioles and also pulmonary blood vessels, visceral pleura, nerves and hilar lymph nodes.
Bronchial circulation
Structures in the _____ Zone receive oxygen directly by diffusion from the alveolar air and receive nutrients from the mixed venous blood in pulmonary circulation.
Respiratory zone
blood in the LA has slightly _____ O2 concentration than blood in the pulmonary capillaries
Lower
What is the pulmonary circulation numerically?
25/8
Is pulmonary capillary pressure a filtration or absorption force?
Filtration force
Pulmonary blood volume accounts for ____ % of blood volume (450ml) but is is highly variable.
~9%
Volume of pulmonary blood flow ____ during inspiration
increases
Lying down _____ the pulmonary blood volume
increases
Disease states (ex. heart failure) can ______ pulmonary blood volume
increase
T/F: Pulmonary vessels are far more distensible (compliant) and able to alter their size and adjust to changing pulmonary volumes.
True
T?F: Even though Cardiac Output increases 4-7 times with heavy exercise, there is only a small increase in pulmonary artery pressure.
True
What will opening more capillaries do to total resistance?
Decrease R
In pulmonary circulation, MAP = ______
CO x PVR
An increase in blood flow leads to a ____ in pulmonary resistance
Decrease
An increase in Flow (CO) to lungs will decrease pulmonary Resistance through what 2 mechanisms?
- Recruitment of pulmonary capillaries
2. Distension of pulmonary capillaries
T/F: The Pulmonary Circulation is not as Prone to Hypertension as the Systemic Circulation.
True
When PAO2 (Alveolar concentration of O2) drops 70% below normal, adjacent blood vessels ______
constrict.
If instead PAO2 is high, adjacent vessels will _____
dilate.
The functional result is that blood is delivered to alveoli where it will be ______ at gas exchange.
most effective
What then would happen throughout the pulmonary circulation at a high altitude where PAO2 is reduced?
Pulmonary hypertension in all vessels
Does the same response happen in the systemic circulation when PaO2 levels drop?
No
___ matches blood flow to well vented alveoli via vasoconstriction
Alveolar Hypoxic Pulmonary vasoconstriction
The following are \_\_\_\_ of pulmonary arterioles: •High O2 in alveoli •Dopamine •Bradykinin •Prostacyclin •Nitric Oxide •Histamine (H2) •Acetylcholine
Vasodilators
The following are \_\_\_\_ of pulmonary arterioles: •Low O2 in alveoli •High CO2 in alveoli •Norepinephrine •Angiotensin II •Endothelin •Vasopressin •Thromboxane A2
Vasoconstrictors
_____ Vessels: Pulmonary capillaries, smallest arterioles & venules
Alveolar
_____ Vessels: All other vessels outside of the Pulmonary capillaries, smallest arterioles & venules
Extra-alveolar
_____ is the the total of Alveolar Vessels + Extra-alveolar Vessel Resistance
PVR
During inspiration, _____ vessels are compressed/elongated
Alveolar vessels
During inspiration, alveolar vessels are compressed/elongated and their resistance _____
increases
During inspiration, Extra-alveolar vessels have _____ resistance
decreased
At low lung volumes, extra-alveolar vessel resistance _______, which _______ total PVR.
increases; increases
At high lung volumes, alveolar vessel resistance _____ which _____ total PVR.
increases; increases
At high lung volumes, ______ vessel resistance increases which increases total PVR.
alveolar
At low lung volumes, _____ vessel resistance increases, which increases total PVR.
extra-alveolar
The volume of air in the lungs after a normal (TV) expiration.
FRC (Functional Residual Capacity):
Zone 3 (at Base) has the highest ____ and thus the highest blood flow per alveolus.
hydrostatic pressure
When in an upright position, there is a _____ difference in pulmonary arterial pressure from the apex to the base of the lung. Due to gravity!
23 mmHg
Which zone of the lung has greatest blood flow?
Zone 3
The hydrostatic pressure of the blood inside of the capillaries (Pa) favors _____ (filtration or absorption); also helps to keep the vessels open
filtration
Is Pa greater in zone 3 or zone 1?
Zone 3
The ______ (largely based on alveolar air pressure–PALV) outside of the capillary opposes filtration and favors vessel collapse.
tissue pressure
Zone ____: Pa is lower than PA. Capillaries are compressed.
Zone 1
If Pa _____ (hemorrhage) or PA _____ (positive pressure breathing), a greater potion of the lung is converted to Zone 1.
drops; increases
Zone ____: Higher Pa (due to gravity) means that Pa is higher than PA during systole. During diastole Pa will drop lower than PA. Thus blood flow is intermittent.
Zone 2
Zone _____:Highest Pa (due to gravity). Region of continuous blood flow because Pa remains higher than PA during both systole and diastole
Zone 3
The majority of healthy lungs use which zones for gas exchange?
Zone 2 and 3
Exercise converts zone ____ to zone ___
2 to 3
When in the supine position, the lungs mostly have zone _____ blood flow
ZOne 2
Normal Whole Lung V/Q is ____
0.8
Do lungs receive more blood or air?
Blood
In a normal individual, the apex of the lung has a ____ V/Q than the rest of the lung.
higher
As one moves from Zone 1 to Zone 3, there is a slower increase in ____ than ______
ventilation than blood flow.
_____ breaths in upright position cause V/Q mismatch because air flows to upper lobes and blood to lower lobes.
Fast, shallow
Alveoli at the ____ of the lungs receives more ventilation than those in the ____
base; apex
The pulmonary capillaries at the ___ on the lungs receive more blood flow than those in the ____
base; apex
In the \_\_\_\_ of the lung; Intrapleural pressure is more negative Greater transmural pressure gradient Alveoli larger and less compliant Less ventilation
Apex
In the \_\_\_\_ of the lung: Intrapleural pressure is less negative Smaller transmural pressure gradient Alveoli smaller and more compliant More ventilation
Base
In the \_\_\_\_ of the lung: Greater vascular pressures More recruitment, distension Lower resistance Greater blood flow
Base
In the \_\_\_\_ of the lung: Lower intravascular pressures Less recruitment, distension Higher resistance Less blood flow
Apex
Apex of Lung: V/Q ratio = ____
> 1.0
If VENTILATION is limited, •V/Q is ____
Decreased
If VENTILATION is limited, Thus O2 is ___ & CO2 is ___
Decrease; Increase
If VENTILATION is limited, Smooth muscles in the ____ constrict
Vasoconstrict
V/Q mismatch responds to ____ feedback
Negative
If PERFUSION is limited, •V/Q is ____
Increased
If PERFUSION is limited,•Thus O2 is ___ & CO2 is ___
Increased; Decreased
If PERFUSION is limited,•Smooth muscles in the ____ constrict
Bronchoconstrict
Blood traverses pulmonary capillaries in ____ seconds and gas exchange must occur during this time frame
0.3 -0.8 seconds
If Pif is negative, it is a _____ pressure
Filtration
The following are ______ pressures
•Capillary Pressure (Pc) = 7 mmHg•Interstitial Fluid Pressure (Pif) = -8 mmHg (use absolute value)
•Interstitial Colloid Osmotic Pressure (if) = 14 mm Hg
Filtration Pressures (29 mmHg)
Fluid that leaves the capillaries is absorbed by _____ circulation and returned to the circulation.
lymphatic
The balance of pulmonary capillary and interstitial hydrostatic and colloid pressures can be disrupted resulting in _____ (large increases in net capillary filtration).
pulmonary edema
______ can occur with left sided heart failure, mitral valve stenosis, damage to pulmonary capillary membranes, etc.
Pulmonary edema
Extra fluid that enters the alveoli will be sucked into the interstitial space due to the slight negative pressure and then picked up by lymphatic capillaries. This keeps the alveoli ____
dry
