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PhysTest4

QuestionAnswer
Where does gas exchange occur? Alveoli & smallest bronchioles
Branches 1-16 make up the conducting zone (more superior) also called what? Anatomical Dead Space
Branches 17-23 make up the respiratory zone (more inferior) also called what? Exchange Zone Ventilation Volume
This lung structure has smooth m & pulmonary a, but no cartilage which allows for large diameter change. Bronchiole
This lung structure has smooth m, submucosal gland, pulmonary a. and cartilage (which allows for rigidity). Bronchus
What controls airway dilation in smooth m of bronchi? SNS to b2 receptor
What controls airway constriction in smooth m of bronchi? PNS to M receptor
These terminal respiratory units are small airways & alveoli served by a teminal bronchiole. Acinus
Walls of alveolar ducts are made entirely of what? Alveoli
This airway is the only airway which contains no cilia, smooth m or cartilage. Alveoli
This airway only contains some cilia and smooth m, no cartilage. Resp. Bronc.
Pulmonary artery receives all of this to help vascularize alveoli surrounding them completely by pulmonary capillaries. Cardiac Output
Pulmonary Artery pressure of 20cm of water (15mmHg) needed for flow of 6L/min is indicative of what type of pressure? Low pressure in pulmonary circulation
Alveolar Epithelium is what layer of the blood-gas barrier? Outer layer
Interstitial Fluid is what layer of the blood-gas barrier? Middle Layer
Capillary Endothelium is what layer of the blood-gas barrier? Inner Layer
What controls blood acid/base status in the lungs? CO2 and bicarbonate
The kidney regulates these levels in the blood. Bicarbonate
The lungs have short term control to regulate these levels in the blood. CO2
INC ventilation (hyperventilate) DEC PaCO2. Are you more or less acidic? Less Acidic=DEC PaCO2
DEC ventilation (hypoventilate) INC PaCO2. Are you more or less acidic? More Acidic=INC PaCO2
Because the lungs receive all of the body's blood they are good for doing what? Changing blood-borne materials before returned to general circulation.
In the lungs what converts Angiotensin 1 to 2? Angiotensin Converting Enzyme
In the lungs bradykinin and prostaglandins are activated or inactivated? Inactivated
What is removed from circulation for uptake & storage by the lungs? Serotonin
What is released in the lungs that's a blood-borne substance? IgA
VO2 describes what? Oxygen Consumption
VCO2 describes what? Carbon Dioxide Production
The Respiratory quotient(RQ) = Respiratory Exchange ratio. What does it show? Ratio of carbon dioxide production/oxygen consumption
An RER of .7 indicates a diet heavy in what? Fats
An RER of 1 indicates a diet heavy in what? Carbohydrates
An RER of .8 indicates a diet heavy in what? Protein or mixed consumption of fats/carbs (assume this value if one is not given).
The coupling of lungs and chest wall due to intrapleural fluid (cohesion btwn parietal & visceral pleura) and a sealed pleural cavity help determine what? Lung Volume
Intrapleural pressure keeps lungs expanded & chest wall from overexpanding. Is it more or less than atmospheric pressure. Less than atmospheric (4mmGg or 5cm water)
Lung elastic forces favor collapse or expansion? Collapse
Chest wall elastic forces favor collapse or expansion? Expansion
Collagen & elastic fibers in interstitial matrix along with surface tension forces in the alveoli causes what? Lung Elastic (Recoil) Forces
Tendons and muscles between ribs cause elastic forces where? Chest wall
Negative intrapleural pressure is used to counteract elastic forces from where? Chest wall and lung elastic forces
Pneumothorax, air in the pleural cavity, cause what to occur? Lung collapse on damaged side & chest wall will spring away.
Absence of gas from all or part of a lung due to failed expansion is called what? Atelectasias
The diaphragm flattens on contraction, external intercostals elevate ribs & sternum and SCM and scalenes help during this process. Inspiration
An increased volume in the chest cavity during inspiration will do what do intrapleural pressure & lungs? Intrapleural pressure DEC, Lungs EXPAND
During quiet breathing what is sufficient for causing inspiration? Diaphragm only
During exercise what is needed for inspiration? All muscle groups: diaphragm, external intercostals, SCM & Scalenes
During exercise the diaphragm goes from compressing 1 cm to as much as? 10cm
What causes intrapleural pressure to increase and thus cause air out(expiration)? Increased pressure caused by DEC Volume.
During quiet breathing, expiration is passive. Does the diaphragm contract or relax? Relax
During exercise, expiration is active. What muscles CONTRACT? Abdominal m. contract forcing diaphragm UP Internal Intercostals contract forcing ribs/sternum down.
During exercise, expiration is active. What will happen to intrapleural pressure? Will become positive (increase pressure).
Expiration against a closed glottis is called this. Valsalva Maneuver
At maximum inspiraiton intrapleural pressure will of from -5cm H20 (at rest) to what? -8cm H20 at max inspiration.
During inspiration will alveolar pressure(airway pressure) be positive or negative? Airway pressure will be Negative pulling air in from high to low.
During expiration will alveolar pressure(airway pressure) be positive or negative? Airway pressure will be Positive pushing air out from high to low.
How can you estimate the amount of anatomical dead space (volume of gas in conducting airways)? 1mL Vd/lb of body weight: example: 150lbs=150mL Vd
What is the normal rate of alveolar ventilation? 5250 mL/min
Humidification of air system, dust removal and decreased velocity of air flow all caused by this. Anatomical Dead Space
Where are pulmonary capillaries NOT all open at a given time (some alveoli ventilated without being prefused)? Alveolar Dead Space
How will a pulmonary emboli effect alveolar dead space? Will increase alveolar dead space
This is equal to the amount of anatomical dead space + alveolar dead space. Physiological Dead Space (in healthy person=anatomical dead space).
This is the volume of air moving in & out of lungs with each breath (typically at rest is 500mL) expressed by Vt=Vd + Va Tidal Volume=Dead Space Volume+Alveolar Ventilation Volume
This is the amount of tidal volume (Vt) NOT available for gas exchange. Dead Space Volume= 1mL/lb of body wt
This is the amount of tidal volume (Vt) available for gas exchange. Alveolar Ventilation Volume (Va)
The total volume moved in/out of lung/min is described as V(dotT)=Tidal Volume * breath/min. This gives you what value? Minute Ventilation
When V(dotA)=Va * breath/min what value are you getting? Functional (alveolar) minute ventilation
What provides a better estimate of gas exchange than minute ventilation? Functional (alveolar) minute venilation= V(dotA)=Va*breath/min
You see oxygen pressure rising quickly and CO2 pressure dropping quickly. Hypoventilation or Hyperventilation? HYPOventilation
You see oxygen pressure rising slowly and CO2 pressure dropping slowly. Hypoventilation or Hyperventilation? HYPERventilation
A decrease in PaO2 caused by hypoxia or hypoxemia is seen when? Decreased Alveolar Ventilation (Hypoventilation)
An increase in PaCO2 caused by hypercapnia is seen when? Decreased Alveolar Ventilation (Hypoventilation)
An increase in PaO2 caused by hyperoxia is seen when? Increased Alveolar Ventilation (Hyperventilation)
An decrease in PaCO2 caused by hypocapnia is seen when? Increased Alveolar Ventilation (Hyperventilation)
During hypoventilation will PaO2 be increased or decreased? Decreased
During hypoventilation will PaCO2 be increased or decreased? Increased
During hyperventilation will PaO2 be increased or decreased? Increased
During hyperventilation will PaCO2 be increased or decreased? Decreased
Hypo- and Hyperventilation can affect what via PaCO2 levels? Acid/Base status
What is typically normal Tidal Volume? 500mL
This volume exhaled after normal expiration is typically 1000mL ERV: Expiratory Reserve Volume
This volume remaining after maximal expiration is typically 1200mL RV: Residual Volume
This volume is found by taking the Total Lung Capacity-Residual Volume (TLC-RV). Typically is 4500mL Vital Capacity
This volume is found by taking the End Residual Volume (ERV) + Residual Volume (RV). Is typically 2200mL Functional Residual Capacity
This volume is found by taking the Vital Capacity (VC) + Residual Volume (RV). Typically 5700 Total Lung Capacity
When the lung or chest wall is less distensible there is (Inc or Dec) Compliance? Decreased Compliance=Restrictive Lung Dz -Pulm Fibrosis -Partial Resp m. Paralysis -Massive Obesity -Rib Fusion
A greater change in intrapleural pressure is needed to produce the same change in volume under these conditions. Decreased Compliance=Restrictive Lung Dz -Pulm Fibrosis -Partial Resp m. Paralysis -Massive Obesity -Rib Fusion
Lung volumes are reduced for a given respiratory effort during these conditions. Decreased Compliance=Restrictive Lung Dz -Pulm Fibrosis -Partial Resp m. Paralysis -Massive Obesity -Rib Fusion
When there is a decreased compliance this is a sign of what? Restrictive Lung Dz
Pulm Fibrosis, Rib Fusion, Massive Obesity & partial respiratory m parlysis are all signs of this disease. Restrictive Lung Disease: -DEC Compliance
A reduction in total lung capacity (TLC) along with a smaller residual volume (RV) is seen during this state. Decreased Compliance=Restrictive Lung Dz -Pulm Fibrosis -Partial Resp m. Paralysis -Massive Obesity -Rib Fusion
During restrictive lung disease (DEC compliance) you see smaller TLC and RV. Will you see an abnormal ratio of RV:TLC? Ratio of RV to TLC will be in the normal range (.2-.3) because all lung volumes decrease.
What is the normal ratio for residual volume to total lung capacity? .2 to .3
When there is an increase in airway resistance this is called what? Obstructive Lung Disease -Asthma -Bronchitis -Emphysema
This disease constricts airways & increases mucus secretion. Called? Example of what type of Dz? Asthma (Obstructive Lung Dz) -INC RV, TLC normal, DEC VC, INC ratio of RV:TLC -INC RV, FRC & TLC (if Chronic)
This disease caused by bronchi inflammation & increased mucus secretion. Hypertophy of mucus glands will occur. Called? Example of? Bronchitis (Obstructive Lung Dz)=COPD -INC RV, TLC normal, DEC VC, INC ratio of RV:TLC -INC RV, FRC & TLC (if Chronic)
This disease is caused by alveolar degeneration, increased compliance & early airway closure on expiration. Called? Example of? Emphysema (Obstructive Lung Dz)=COPD -INC RV, TLC normal, DEC VC, INC ratio of RV:TLC -INC RV, FRC & TLC (if Chronic)
Bronchitis and Emphysema are referred to as what? Example of? COPD (Obstructive Lung Disease) -INC RV, TLC normal, DEC VC, INC ratio of RV:TLC -INC RV, FRC & TLC (if Chronic)
Patient presents with an increased RV to TLC ratio. Dx? Obstructive lung disease -Asthma -COPD (Emphysema or Bronchitis)
The maximum forced expiration beginning at max inspired volume is generally smaller than vital capacity measured normally; called? Forced Vital Capacity: To Assess Lung Fcn
The forced expiratory volume at some set time after beginning expiration, usually 1 is called what? Forced Expiratory Volume (FEV). If at 1 second called (FEV1).
In the normal lung, what is the typical FEV1 (Forced Expiratory Volume @1s)? 80% of the Forced Vital Capacity (FVC)
The maximum forced expiration beginning at max inspired volume is generally smaller than vital capacity measured normally; called? Forced Vital Capacity: To Assess Lung Fcn
The forced expiratory volume at some set time after beginning expiration, usually 1 is called what? Forced Expiratory Volume (FEV). If at 1 second called (FEV1).
In the normal lung, what is the typical FEV1 (Forced Expiratory Volume @1s)? 80% of the Forced Vital Capacity (FVC)
On a spirometer reading would you see the FVC or FEV1 occur first? FEV1 (Forced Expiratory Volume at 1s)
This spirometer value is a function of lung size, lung elasticity & Airway Diameter(Airway Resistance) FEV1 (Forced Expiratory Volume at 1s)
FEV1 is often expressed as a ratio w/FVC why? Corrects for Body Size: FEV1/FVC% aka FEV1%
What's the ideal value for FEV1%, what do you normally see? Ideal=1=100% Normal=.8=80%
During obstructive disease what would you expect your FEV1% to be? Half the size of normal ~42%
During restrictive disease what would you expect your FEV1% to be? Normal to slightly increased ~90%
When airway diameter decreases, where does more reduction occur, the FEV1 or FVC? FEV1
This measure of peak flow during max effort can be measure at home. Quanitifies airflow obstruction. Monitors more than dx. Good for Asthma sufferers to check. Peak Expiratory Flow (PEF)
Compliance on spirometry is a sign of this? Residual volume
Lungs recoil (collapse) with force because of these 2 things? Alveolar Surface Tension Elastic Fibers in Lung
By filling the lung w/saline what would you completely eliminate? Surface Tension Forces
Decrease in Surface Tension Force would do what? Lead to INC Compliance
Comparing inflation v deflation in lung, is surface tension higher at which part? Inflation (Breathing In) _Caused by surfactant redistribution which disrupts the surface tension
Higher lung volume will do what to compliance? DEC
Pulmonary Fibrosis will do what to compliance? DEC because fibrotic tissue makes expansion more difficult.
Pulmonary Congestion will do what to compliance? DEC
Surfactant Deficiency will do what to compliance? DEC
Edema will do what to compliance? DEC
Low Lung Volumes do what to compliance? INC
Emphysema does what to compliance? INC because elastic fibers are destroyed by proteases & elastases.
Old age does what to compliance? INC
Functional Residual Capacity (FRC=ERV+RV) is the volume of lungs at rest during normal expiration (open airway). What DEC it? Restrictive diseases (fibrosis) which decrease compliance of lung/chest wall
Functional Residual Capacity (FRC=ERV+RV) is the volume of lungs at rest during normal expiration (open airway). What INC it? Emphysema which allows the chest wall to expand the lung leading to a barrel-shaped chest.
Water in alveolar walls generate this that minimizes alveolar size & resists inflation. Upon increasing radius, this decreases. Collapsing Force
Collapsing Force can be explained by Laplace's Law. What is it? P=2T/r P=Collapsing (inward) Pressure T=Surface Tension r=radius
Do small alveoli tend to empty into larger or smaller alveoli? Larger going from high collapsing pressure to low.
Atalectasias The tendency of alveoli to collapse
Atalectasias is opposed by two things? Alveolar Surfactant & Interdependence of Alveoli
How does alveolar surfactant effect atalectasias (tendency of alveoli to collapse) Opposes by interrupting interactions btwn water and thus decreasing tension forces. INC Compliance and DEC work of breathing
Surfactant will do this to Compliance & Breathing Increase compliance-->Easier to breathe(less work)
The balance of forces between alveoli (interdependence) helps to do what? Increase compliance by canceling out eachother's collapsible forces-->Easier to breathe(less work)
What is surfactant made of? DPPC(phospholipid), Lipids & Protein
What makes surfactant? Type 2 Alveolar Epithelial Cells
Infants born prematurely before 24wks have how much surfactant? None therefore lungs may collapse completely when breathing out because hard to reinflate w/small radius & weak inspiratory mm.
Infants born prematurely between 24-35 wks have how much surfactant? Some
Infants born prematurely >35 wks have how much surfactant? Sufficient
In heart surgery, smokers what is the level of surfactant? DEC
How much of your metabolic rate is needed to breathe. 2-3%.
In emphysema how much resting metabolic rate do you need to breathe? 30%
Total work for breathing equals? Elastic work+Resistance Work
The work needed to expand the lung due to surface tension & elastic elements is dependent on Lung Volume. Called Elastic Work _During quiet breathing=65% of total
The work needed to move air through airways is primarily dependent on airway diameter and flow velocity. Called Resistance Work _During quiet breathing=35% of total
Increasing flow velocity will do what to resistance work? Increase air turbulence and thus increase work.
Large lung volumes will cause what changes? Decrease airway resistance bc of radial traction forces expanding the airways. Increase conductance Increase elastic work Increase Radial Traction Force
Radial Traction force is reduced in this condition? Emphysema
Radial Traction force is increased in this condition? Fibrosis
During inspiration: Airway resistance decreases
During expiration: Airway resistance increases
During COPD when examining flow rate you would see this in COPD(Chronic Bronchitis,Emphysema) Decrease flow & scooped out appearance. Lower than expected flows in middle volumes.
During forced expiration are the airways dilated or compressed? Compressed limiting flow
This helps emphysema patient exhale by increasing airway pressure. Controls shortness of breath. Pursed Lip Breathing
When lips are in this position transmural pressure gradients cause closure of small airways during exhalation. Lips open
When lips are in this position there is higher airway pressure minimizing premature airway collapse (like pinching a garden hose) thus improving flow by creating a back pressure in the airways. Lips pursed -Pts w/emphysema often do it.
This technique improves ventilation and releases trapped air in the lungs keeping the airways open longer and decreasing the work of breathing. Creates a back pressure in the airways. Pursed lip breathing
Gas exchange occurs by Fick's Law which states? Will diffuse down partial pressure gradient. _Dependent on Membrane Area, Membrane Thickness & Solubulity
Increasing the Membrane Area will do what to diffusion? Increase diffusion
Increasing the Membrane Thickness will do what to diffusion? Decrease diffusion
Increasing solubility will do what to diffusion? Increase diffusion
Which is 10x larger, the CO2 gradient or O2 gradient O2 Gradient Larger
Even though this gradient is larger, it diffuses slower than CO2 why? CO2 is 20x more soluble therefore flows at a faster rate
The CO2 pressure in the Alveoli is greater,equal or less than in the arteries? Equal because of rapid diffusion
The O2 pressure in the Alveoli is greater,equal or less than in the arteries? Increased usually by 5-20mmHg
This equation is used to calculate what? VA = VT * VD Alveolar Ventilation (Va) Vt=Tidal Volume Vd=Dead Space=1ml/lb
This equation is used to calculate what? VdotA = VA * BR Alveolar Minute Ventilation VA=Alveolar Ventilation BR=Breathing Rate
Vital Capacity + Residual Volume give you what? Total Lung Capacity
End Residual Volume + Residual Volume gives you what? Functional Residual Capacity
This equation is used to calculate what? PIox= FIox(PB-47) usually PIox=.21(PB-47) Partial Pressure of oxygen in inspired air(PIox) _PB=Barometric Pressure _Pwater=47 _FIOx=.Fractional Concen of Oxygen in inspired air=.21, will change if supplemental O2 is used or if pt breathes and O2 depleted atmosphere
This equation is used to calculate what? PAox=PIox * [(PaCO2)/.8] PAox=PIox * [(PaCO2)/RQ] Alveolar Gas PIox=Partiral P of oxygen in inspired aire PaCO2=Partial pressure of CO2 in arterial blood RQ=Respiratory Exchange Quotient=.8
By taking the partial pressure of Oxygen in the alveoli (PAox) * partial pressure of Oxygen in arteries (Pa:ox) you find what? A-a Gradient=PAox * Pa:ox
CaO2 = (gm Hb/dL)(ml O2/gm Hb)(SaO2/100) CaO2 = (gm Hb/dL)(1.34)(SaO2/100) Gives you the oxygen concentration. _SaO2= %Saturation of blood Hb (from O2 dissoc cruve) _Gm Hb/dL will be given. _CaO2= # mLO2/100mL blood=mLO2/dL blood=Volume %
The rate of CO2 production/O2 consumption gives you what? Respiratory Exchange Quotion=R, RQ, RER RQ= Vdot CO2/Vdot O2 _May also be given in volumes instead of rates
Change in V/Change in P= what? Compliance
What equals solubility/(square root of MW) Diffusion=solubil/squareroot MW
Increasing surface tension will do what to collapsing force? Increase (P=2T/r)
Increasing alveolar radius will do what to collapsing force? Decrease (P=2T/r)
Decreasing surface tension will do what to collapsing force? Decrease (P=2T/R)
Decreasing alveolar radius will do what to collapsing force? Increase (P=2T/R)
During an obstructive disease what will happen to VC(Vital Capacity)? Decrease. Also happens w/restrictive disease.
What is the only function test that decreases with both obstructive & restrictive disease? Vital Capacity
During obstructive disease state, what will happen to residual volume? Increase
During restrictive disease state, what will happen to residual volume? Decrease
During obstructive disease state, what will happen to functional residual capacity? Increase
During restrictive disease state, what will happen to functional residual capacity? Decrease
During obstructive disease state, what will happen to total lung capacity? No change or increase
During restrictive disease state, what will happen to total lung capacity? Decrease
During obstructive disease state, what is the typical change in FEV1% ? Less than 70%
During restrictive disease state, what is the typical change in FEV1% ? No change or increase
During this disease state VC, RV, FRC & TLC will ALL decrease. The only value that may increase/no change is FEV1% Restrictive Lung
During this step air will become saturated with water, the water vapor will DEC partial pressure of gas in air. At body temp will usually equal 47mmHg. Humidification of Inspired Air (During Inspiration): Step #1
During this step oxygen is extracted from inspired (humid) air gas in alveoli. Partial pressure of Oxygen (PAO2) is fairly stable from breath to breath because the volume in Alveoli(350ml) is much smaller than the FRC (2200ml). Depletion of Oxygen in Alveolar Gas (Step #2)
To describe the relationship between PAO2 (alveolar air) and PAco2 you must find? PAO2=PIO2-(PAco2/RQ)
The calculated PAO2 shows you what? Average value for entire lung
What can show you how altitude(barometric pressure) & fractional oxygen (FIO2) affect aveolar PO2 Calculated PAO2
What shows you that PAO2 and PACO2 are inversely related? The calculated PAO2
PAO2 is more or less than PaO2? More even in normal individuals. Comparing the two=A-a gradient
Diffusion of O2 across alveolar membranes & shunting of blood to non-respiratory areas of lungs effects what? A-a gradient
Do diseases tend to increase or decrease the A-a (Alveolar-artery) gradient? Increase
Step 1 of the Oxygen Cascade Humidification of Inspired Air
Step 2 of the Oxygen Cascade Depletion of oxygen in Alveolar Gas
Step 3 of the Oxygen Cascade Alveolar-Arterial (A-a) Gradient
Diffusion Capacity Dl=AD/T and normally stays constant so pressure gradient is the primary determinant of rate of gas exchange. What can positively change it? Exercise: INC Dl by up to 3x by INC Surface A & DEC Thickness
During exercise more capillary are open to ventilated areas & deep breathing will stretch alveoli. What does this change that will overall effect Diffusion Capacity(Dl) Surface Area (A) increases which will increase diffusion capacity (Dl)
During exercise deeper breathing will stretch alveoli and thin the membrane. What does this change and how will this effect Diffusion capacity (Dl)? Thickness (T) will decrease which will increase diffusion capacity (Dl)
Diffusion Capacity Dl=AD/T and normally stays constant so pressure gradient is the primary determinant of rate of gas exchange. What can negatively change it? Emphysema, Pulm Fibrosis, Pneumonia, CHF
The breakdown of alveolar walls in this disease state leads to decreased surface area & thus decreased diffusion capacity (Dl) Emphysema
Increase in interstital fibrous tissue which increases diffusion distance & thus decreased diffusion capacity (Dl) Pulmonary Fibrosis
Fluid or pus in alveoli which increases diffusion distance & thus decreased diffusion capacity (Dl) Pneumonia
Lung Edema which increases diffusion distance & thus decreased diffusion capacity (Dl) Congestive Heart Failure
what will decrease diffusion capacity? Decrease in surface area (emphysema) or increase in diffusion distance
Single-Breath CO tests are used to determine what? Diffusion Capacity
Max rate at which blood can be delivered to lungs by heart (CO) limits amt of O2 that can be taken up by the lungs states this hypothesis Perfusion Limitation Hypothesis (MORE LIKELY in healthy indiv) _Diffusion is NOT a factor in normal ppl but can become impt under some circumstances
The physics of diffusion across alveolar membranes ultimately limits the amt of O2 that can be taken up by the lungs states this hypothersis Diffusion Limitation Hypothesis (Less Likely in healthy ppl)
An abnormal curve comparing PO2 of blood passing through a capillary will be when? When Blood PO2 NEVER becomes equal to PAO2
An normal curve comparing PO2 of blood passing through a capillary will be when? When Blood PO2 becomes equal to PAO2
There is insufficient time for equilibrium to occur btwn the blood & alveolar gas. Will O2 become diffusion limited? Yes
If Diffusion capacity (Dl) is abnormally low, what happens to oxygen? Becomes diffusion limited
If the PAO2 is abnormally low what happens to oxygen? Becomes diffusion limited
What's the normal time for PO2 to equilibriate? How long does it usually spend in capillary? Takes .25s to equilibriate and spends .75s in the capillary (at rest) so should have enough time.
During exercise CO increases, what would happen to the transit time of oxygen through capillaries? Can go by as quickly as .25s (yet still enough time for PAO2 and blood PO2 to equilibriate)
If diffusion capacity (dl) decreases because of disease what will happen to the oxygen through the capillaries? Will not be able to equilibriate blood PO2 with PAO2 and oxygen transport will become diffusion limited.
Does exercise improve or make worse reduced oxxygenation in disease states(where Dl is abnormally low)? Makes worse, and further reduces oxygenation.
Hypoventilation, Rebreathing, High altitude can all cause what? Low PAO2 where it takes longer for blood PO2 to equilibriate with PAO2.
Severe exercise at high altitude will cause what in normal ppl? Oxygen Diffusion Limited since have decreased capillary transit time(takes longer to equilib) and low PAO2(at high altitude). Will overall not have enough time to equilibriate.
Person traveling to Colorado with emphysema (DEC Dl). Will there conditions get better or worse? Will have more diffusion limited oxygen at higher altitudes, worse.
Created by: glittershined