finalquiz.pft Flashcards
How do we measure indirect volumes?
Performing a SVC maneuver
respirometers measure _______ & reports the results in ________
flow
volume
Peak flow meters measures flow & reports in _______.
Flow
Name the 5 purposes for PFT testing?
Identification (detect disease) quantification (evaluate need) Epidemiological (identifies pulmonary abnormalities from environment or occupational risk screening Post Op Risk Pulmonary disability Therapeutic Effectiveness
Name 5 volumes that can be measured directly?
Vt, IRV, ERV, IC, VC
T or F: Tidal volume has great variation & may abnormal readings are always indicative of disease.
False, Vt is not indactative of disease due to great variance
What is an average Vt?
500 - 700 mL
This value is part of normal breathing, is consistent at resting, you would exhale maximally to obtain reading of this expiratory level?
ERV
If you tell a patient to take a maximal inspiration followed by a maximal exhalation without force you would be looking to get what type of measurement?
SVC
The SVC will provide important volumes used to determine ________ disease.
Restrictive disease
Maximum volume of air inspired following normal inspiration but is not clinically significant, obtained from SVC
IRV
A normal exhalation, when you inhale maximally is describing:
IC
T or F: there is great variation with IC
True
This value can be measured on inspiration or expiration?
VC
Name 5 things that can be provided with a VC maneuver
VT, IRV, ERV, IC, VC
This evaluates lungs ability to move large volumes quickly?
Pulmonary Mechanics
The FVC will provide important flow rates used to determine ________ disease>
Obstructive
Pulmonary Mechanics uses _____ maneuver to obtain results.
FVC maneuver
When an FVC is performed your exhalation needs to last longer than ______ seconds. If it cannot be completed in ______ seconds this indicates obstruction.
6 seconds, 3 seconds
FVC should equal _______.
SVC
FVC can measure what 5 items?
FVC, FEV1, PEFR, FEF 200-1200, FEF25-75
This measurement is sometimes used to evaluate asthmatic patients pre & post bronchodilation, is seen on flow volume graph as the highest point.
PEFR
What is a normal value for PEFR?
600 l/min
T or F: PEFR may appear normal in abnormal patients & is also effort dependent?
True
Decreased values in this measurement is associated with large airway obstruction?
Forced expiratory flow 200-1200
_______ is the best indicator of obstructive disease.
FEV1
T or F: Largest FEV1 is not always largest FVC
True
This measurement is associated with small airway obstruction?
Small airway obstruction
This value is the FEV for a given interval expressed as a % of a FVC
FEV/FVC ratio
A decreased ratio of FEV1/FVC is indicative of _______ disease.
Obstructive disease
A ratio of less than ______ % is indicative of obstructive disease.
70%
A ratio of greater than 70% is indicative of _______ or ______ lungs
Normal or restrictive
The flow volume loop measures _________ and _______ rates of FVC
Flow Volume Loop
Flow per time is measured on the ______ axis & volume is measured on the ________ axis on a flow volume curve.
Flow per time is measured on vertical axis & volume is measured on horizontal axis.
___________ is measured on top part of line & _________ is measured below the base line.
expiration;
inspiration
If you have a flow volume loop that is scooped out this may represent _______ disease; if you see a skinny and tall loop you may have ________ disease.
Obstructive
Restrictive
Fixed obstruction causes:
A. Decrease in inspiratory flow rates only
B. Decrease in expiratory flow rates only
C. Normal flow rates when measured directly
D. Equal decreases in both expiratory & inspiratory flow rates.
D. Equal decreases in both expiratory & inspiratory flow rates
If you have a flattened flow volume loop on the expiration side this would indicate what type of obstruction?
Intrathoracic variable large airway obstruction or fixed large airway obstruction
If you see a relatively normal expiratory flow curve but a small volume, flattened curve on inspiration you probably have what type of obstruction?
Extrathoracic variable large airway obstruction
If you have a flow volume loop that looks flattened & smaller on both inspiration & expiration you probably have?
Fixed large airway obstruction
When you are testing for reversibility of an obstructive pattern you would need to see an increase of more than _______% following application of bronchodilator.
15%
When a PFT test is performed how long should a patient refrain from using their bronchodilator before testing occurs?
8 hours prior to testing
What test is used to look for a reactive airway? It is called _________ or __________
Bronchial provocation or methacholine challenge
What value should be seen in order to see a positive result in the methacholine challenge?
It is a 20% decrease in FEV1
When given this test you would instruct the patient to breathe in & out as fast as possible until told to stop; normally performed in 12-15 seconds often in a panting maneuver?
Maximum voluntary ventilation
What type of measurements is gold standard for diagnosing restrictive condition?
Lung Volume
If you needed to obtain a height on a person who is a double amputee how would you find it?
Measure finger to finger to approximate weight
PD20% represents:
A 20% decrease in FEV1
This measurement can gives us a picture of a patients muscular mechanics?
Max Voluntary ventilation
What method of drug administration is used to administer the methacholine challenge?
Nebulizer or dosimeter
The largest volume & rate that can be breathed per minute by voluntary effort is _____________.
Maximum voluntary ventilation
The predicted values for evaluation of PFT is based on what 3 factors?
Age, height, sex
If you test positive on the PD20% which means you have a decrease of 20% in your fev1 you probably have ___________ airways.
Reactive airways
Pulmonary mechanics is looking at ________ of a person.
Airflow
What are some reasons a person may have poor or decreased MVV measurements? 5 reasons
Obstructive disease Airway resistance muscle weakness decreased compliance poor patient effort
The MVV measures the amount of air moved within _________ seconds.
12-15 seconds
Name 3 things measured in PFT tests.
Lung volumes/capacities
Flow rates
Gas diffusion
What is the scale used to interpret normal vs abnormal results? Measured in percentages
80-100% = normal pft
60-79% of predicted = mild disorder
40-59% of predicted = moderate disorder
40% of predicted = severe disorder
If you have a patient with these values how would you diagnose him/her?
56 year old female
FVC = predicted (5.10); Observed (3.30); % predicted = 64.7%
FEV1 = Predicted (3.83); Observed (3.18); % predicted = 83%
FEV1/FVC % = Predicted 75%; Observed 96%
Volume (FVC) decreased 65% of predicted
FEV1 are normal (83% of predicted)
Since the FEV1 is normal no obstructive problem is identified but since FVC volume is decreased the patient appears to have a mild restrictive problem
DX: Mild Restrictive only
How would you diagnose this patient? 48 year old man: FVC = 81.9% of predicted FEV1= 44.6% of predicted FEV1/FVC % = 41%
Volume (FVC) is normal when above 80% which would indicate no restrictive problem The flows (FEV1) are decreased 44% of predicted so there appears to be a moderate obstructive problem
DX: Moderate obstructive only
If a patient is testing for an obstructive condition what is the next study that should be done?
Post bronchodilator study to see if obstruction is reversible
T or F: RV can be measured directly.
False; RV cannot be directly measured
In order to obtain a measurement for FRC & TLC you also must measure ________
RV
Name 3 tests or ways you can measure FRC?
Helium dilution
Nitrogen Washout
Body Plethysmography
The nitrogen washout method or N2 is a open/closed method of obtaining FRC?
Open Method
How is FRC measured with the Nitrogen Washout method, explain the process & what other gases if any may be used.
FRC is washed out of the lung by having the patient inspire 100% O2; The washout FRC goes into a colleting spirometer & is measured to calculate the FRC
A N2 washout of ________ minutes indicates normal lungs whereas a time that is greater than ________ indicates poor distribution.
2-3 minutes = normal
> 7 minutes = poor distribution
If you have a leak in your system during the N2 or nitrogen washout test what happens to your FRC?
FRC is artificially raised
When performing the \_\_\_\_\_\_\_\_\_\_\_ test for measuring FRC you are looking at the distribution of air trapping in the lungs. A. Nitrogen Washout B. He Dilution C. Body Plethysmography D. Calibration
A. Nitrogen Washout
T or F: When you are calibrating a gas analyzer which is used to confirm standards of PFT testing you must calibrate analyzers on same gas that is used in the test?
True
This is the resting volume left in the lungs when you do not inhale or exhale; it can be the volume left after a quiet exhale
FRC
T or F: Weight never affects a predicted value in PFT testing
True
T or F: Lung size may change if a patient is profoundly obese due to the restrictive area left in the cavity.
False
What is normal value for FEV1/FVC?
Our value is 72%
T or F: The FEF 200-1200 is a vital component of the PFT testing for us to measure flow and thus obstruction.
False, Peak flow will tell us same thing so don’t really need; it is an indicator for large airways
What measurement may be good for classification for pulmonary and/or occupational purposes?
FVC
During PFT testing what is the maximum parameter or time that can be measured during exhalation.
15 seconds
When performing PFT testing for SVC & VC the tests should start within _______ ml of each other.
.2mL
If you increase FRC what will happen to the alveoli in the lungs?
The alveoli will stay open longer period of time so the IC & Vt will lower
T or F: The values of RV & FRC cannot be manipulated or changed in lungs.
False, RV & FRC can be raised in certain lungs
What type of maneuver can be done to improve oxygenation?
Peep maneuver
What flow level must be met in order for an MDI to work effectively?
60 lpm
Name the 6 characteristics or principles that must be applied to flow or volume equipment.
Capacity Accuracy Error Linearity Output
Name 3 examples of volume measuring devices.
- Water sealed spirometers/stead wells that measure volume & time (Stead Wells, Water Sealed Collins)
- Dry Rolling Seal (pistons with rolling diaphragm)
- Bellows spirometer
Flow measuring devices are known as _______.
Pneumotachometers
Name 5 types of pneumotachometers or flow measuring devices.
Turbine device - Wright Respirometer (turbinometers);
Fleisch which measures pressure differential or resistance
Thermal- flow cooled
ultra sonic-signal disrupted by change
Peak Flow Meters
What is the formula to find Vt if you have I time & flow?
Vt= Flow X I time
T or F: Flow can be converted to volume when using some flow measuring equipment
True
What is a normal value on the Peak Flow Meter
600 lpm
When using _________ to measure flow repeatability is more important than accuracy and its reproducibility should be within 0.67 l/sec or 40 lpm
Peak Flow Meters
What do you call a principle of pulmonary function testing in which the accuracy of the measurement exists over its entire range of measurement?
linearity
A principle of PFT equipment that represents how much the equipment can measure?
Capacity
Reliability of PFT equipment is called ______.
Precision
The specific measurement made is called _____.
Output
If you have only spirometry values to analyze as you do not have a complete PFT test but the FVC = SVC but you notice the values are low this would imply what type of condition?
Restrictive
This is the gold standard of identifying obstructive conditions?
FEV1 values
Name 2 types of problems you may experience when measuring for FRC?
Patient problem
Leaks or problem with equipment
When measuring for FRC this type of test is done when the patient is panting against an open & closed shutter?
Body Box
What must occur to obtain a valid measurement of FRC for helium or Nitrogen testing?
Equilibration
When performing Plethysmography what gas law is used to determine total thoracic gas volume
Boyles Law
Intrapulmonary volume is abbreviated as
VTG or TGV
T or F: In normal patients VTG = FRC
True
When using body box because air flow is not possible against a closed shutter mouth airway pressure = ___________.
Alveolar pressure change
When using the body box or plethysmography a graph is created which shows ________ & ________ changes?
Pressure & Time changes
T or F: When utilizing the plethysmograph the cabin the patients sits in must be pressurized & internal pressure is monitored & compared to external atm pressure
True
What is Boyles Law?
P1V1=P2V2
HE dilution for measuring FRC is considered an open or closed system?
Closed Method
T or F: After equilibrium occurs the changed level of O2 is used to determine FRC once He is diluted & equilibrium occurs.
False; The change in He? is used to determine FRC because there is no helium in lungs normally; measurement occurs after equilibrium occurs
T or F: Helium is an inert gas
True
In order to have a valid test your extrapolated volume for flow rates should be less than _______.
Less than 5% or .150 l
If your FVC , SVC your patient may have what type of condition?
Obstructive
When you are measuring FEV1 the result is reported as __________ but is actually ________ value.
FEV1 reported as volume but is actually flow
This is the volume exhaled before zero time point, no more than 5% of VC is allowed.
Extrapolated value
T or F: The larges FEV1 will always lead to the largest FVC
FALSE; the largest FEV1 does not always = largest FVC
This is the average air flow during mid portion of FVC.
FEF 25-75
If you have a reduced value of FEF 200-1200 then you may have large or small airway obstruction.
Large airway obstruction
This value is located on the highest point on volume flow graph & sometimes shows normal in abnormal patients.
PEFR
When ______ value is decreased this is a symptom of small airway obstruction
PEF 25-75
If you see an increased MVV value you have an increase in __________. If you see a decrease in MVV then you have _________ condition.
Increased Raw
Decreased = obstructive condition
A method of measuring FRC (RV & TLC) in which gases are measured that are in communication with obstructed airways & does not take into account all airways.
He or Nitrogen washout
When using the Nitrogen Washout method how do you remove the patients nitrogen?
Have them inspire 100% O2 for 2-5 minutes
What happens to the patients Nitrogen once it is removed?
A. It is released into atmosphere as it is inert
B. It is recycled back to lungs after exhale
C. FRC washout goes to a collecting site to be measured
D. It is converted to a liquid for proper measurement
C. FRC washout goes to a collecting site to be measured
This type of test for FRC can measure gases trapped. A. Helium Dilution B. Nitrogen Washout C. Body Plethysmography D. Both A & B E. All of the above
C. Body Plethysmography
Besides measuring FRC another value that can be provided by use of body box includes?
Airway Resistance
What is the scale of Severity of Raw
2.8 to 4.5 cmH2o/L/Sec = Mild
4.5 - 8 = moderate
> 8.0 = severe
What is a normal resistance value?
0.6 - 2.8 cmH2O/l/Sec
What test is used to find airway resistance?
Body Box test
Compliance is found by _______ change per unit of _______ change
Volume change per unit of pressure change
What two parameters must be calibrated in order to determine accuracy of body box?
Pressure & Flows
_______ is determined by volume change per unit of pressure change?
Compliance
________ is determined by measuring changes in pressure vs. flow.
Airway Resistance
When calibrating the pressure of a body box what is used to verify pressure against?
Mercury or water manometer
Flows are verified with what device?
Rotameter
Name 3 advantages of using a body box? Name 3 disadvantages?
VTG not affected by lung ventilation
Test is quicker
Easily repeatable
Disadv: Patient may not be able to physically enter the body box, Claustrophobia, Patient may not be able to pant
Name 3 methods of Calibration when analyzing a gas for FRC or D1CO & quality control?
Utilize known gas value
Mechanical lung analog
Test known subjects
What is the name of a gas analyzer?
Clark Electrode (which is polargraphic) or galvanic fuel cell
What is the name of the He analyzer?
Wheatstone bridge which measures thermal conductivity
What is the name of the analyzer for N2?
Geisler tube ionizer
What is the name of the analyzer for gases of stress testing?
Mass Spectrometer
What analyzes for DLCO testing?
Chromatograph or infrared absorption
Gas analyzers are calibrated by calibrating to zero and by adding a gas::
A. Running a gas that is a mixture of the gas that the device normally measures with an inert gas
B. A gas that is free of that particular gas the device tests for
C. Removing all gas & adding liquid
D. Adding O2 only as this is a major gas we have in lungs that must be tested for.
B. A gas that is free of that particular gas the device tests
When measuring for airway resistance raw is calculated from two curves, what do they represent?
The first curve is produced when the shutter in the box is open and flow is plotted against box pressure which produces an S-Shaped curve.
The second curve is created after the shutter is closed that plots mouth pressure against box pressure
When you see an increase in Raw during exhalation this is indicative of what type of abnormality?
Obstructive airways disease such as emphysema
An increase in resistance is represented in what way on the s-curve?
The curve will change from a skinny narrow double line to showing a wide type on the expiration side of the graph.
What 3 items must be calibrated on the Body Box?
Mouth pressure transducer
Flow transducer
Cabinet pressure transducer
T or F: Biological testing is a common component of quality control
True
When measuring gas distribution on the single breath N2 elimination test two things are measured, what are they?
Evenness of distribution of inspired gas
Closing volume/closing capacity
When you are using an O2 analyzer which side of equipment should be used if an aerosol is provided?
Always calibrate from dry side
The gold standard in calibration is to analyze where?
As close to patient as possible
What is the name of a pH analyzer?
Sans
This describes what test: Patient first exhales to RV & then inspired 100% O2; The patient then exhales this gas slowly; exhaled gas passes through a N2 analyzer (geisler tube ionizer) to record changes in N2% & the volume of gas is exhaled into a spirometer
Single breath N2 elimination
What are the 4 phases of the SB N2 elimination?
Phase I = Deadspace, 100% O2, no N2
Phase II= combination of deadspace & alveolar gases–N2 begins to increase
Phase III= alveolar gas; evenness of gas distribution is shown by how flat the mid-portion of the test is (poor distribution slants up more)
Phase IV: Shows the sudden rise of N2% & occurs during airway closure, called the closing volume when airway closure occurs
When you add the closing volume to RV you have ________ ___________.
Closing capacity
The sudden rise of N2% that occurs at airway closure is?
Closing volume
What causes closure of the airways?
Compression of lower airways
Name 2 other test methods besides the SBN2 elimination method used to measure gas distribution?
7 minute N2 washout test
Ventilation scans that can also measure distribution of gases
With the onset of obstructive disease what measurement shows initially, often before symptoms experienced? A. Spirometry B. FEV1 C. Peak Flow D. Closing volume
D. Closing volume may show up before spirometry changes in obstructive conditions
What happens to the value of closing volume during obstructive disease?
2 things
Closing volume is elevated
Slope of Phase III is increased
DLCO will measure the diffusion of \_\_\_\_\_\_\_\_\_\_\_ (gas) across the Alveolar capillary membrane. A. Carbon Monoxide B. CO2 C. O2 D. N2
A. Carbon Monoxide
Which gas has an affinity with Hgb that is 210x greater than O2 & diffuses rapidly into pulmonary blood?
Carbon monoxide
When performing a Single breath DLCO test the patient inhales a VC of gas from RV containing a known amount of?
0.3& CO, 10% He, and air
The DLCO test requires a breath hold of _____ seconds?
10 seconds
What is a normal value for DLCO and what is it measured from?
Normal DLco = 25 mL/min/mmHg in STPD
Name 5 factors that affect Dlco?
HB, HCT Body position Breath holding time Lung volume Smoking
What conditions may cause a decreased DLco value?
Pulmonary fibrosis
Sarcoidosis
Ards
Edema
When might you expect to see an increase in DLCO?
Polycythemia Exercise Asthma Obesity Intralveolar hemorrhage, left to right intracardiac shunts
If you see a reduction in DLCO you can have normal lungs if it is caused by what?
Small lungs, a pure reduction in DLCO can represent small lungs
When evaluating alveolar capillary membrane abnormalities which arise from decreased DLCO you must compare DLCO to _______ ______.
alveolar volume
A minimum of ______ procedures must be performed to meet ATS standards.
3 acceptable tests
When evaluating patient performance standards against ATS guidelines name some important rules to identify if you have good results (4)
No false starts
Test should not differ by more than 5%
The “best test” should be determined & used
Best test means = highest FVC & FEV1
What are 4 measurement principles you must evaluate?
Specificity
Sensitivity
Validity
Reliability
To comply with standards of infection control is it necessary to routinely clean interior?
No, you do not have to routinely clean the interior; A clean mouthpiece & tubing is required & low resistance bacteria filter
There is a direct/inverse relationship with volume & compliance
Direct
When you see a reduced diffusion capacity this implies what abnormality?
Loss of pulmonary vascular bed/or parenchyma
This principle of equipment measurement looks at ratio of all patients & looks at positive test results.
Sensitivity
Deals with equipment results that are truly negative?
Specificity
When you have airtrapping what type of change if any will it have on your FRC & RV
both will increase from hyperinflation or obstructive conditions
This measurement is very good for looking at purely restrictive condition but with combined problem this value may not change at all?
TLC
If you have poor distribution like in the case of COPD what happens when looking at distribution of gas?
The closing volume will be different
During emphysema what normally happens to your DLCO value?
It will decrease due to loss of integrity of surface area; it becomes so loose it looses its ability to transfer
When measuring DLCO you are given a ____________ ___________ measurement but it must be converted to __________ __________.
Absolute value;
Relative value
Name a restrictive condition that does not cause a decrease in DLCO?
ALS
Neuromuscular
Exhaled nitric evaluates the activity of ___________ activity which is an indictor of reactive airway.
Eosonophils
What type of condition may cause problems with PFT testing and prevent equilibration or cause pain.
Ear infection
When assessing abnormal lung conditions, when you are looking at obstructive conditions you are looking at _______; with restrictive you are looking at _______.
Obstructive - flows
restrictive- volumes
Normal PFT machines allow for exhalation of up to _____ seconds; Patient should have _______ seconds of exhale.
15 seconds
6 seconds
T or F: PFT tests can be used to diagnose conditions such as COPD or asthma?
False they can only show patterns such as obstruction or restriction
Name two things which are vital to accurate PFT tests?
Patient cooperation, good instructions from RT
When you measure your VC is this a direct or indirect measurement?
Direct
What can a FVC imply if results are abnormal?
It would be used to determine if obstructive condition present
In a normal lung what 2 values should match: If they do not match what could the patient have?
SVC = FVC; airway obstruction
When we refer to pulmonary mechanics this is speaking to ______ of air/
Flow of air; airflow
Two major things that can affect outcomes when measuring FRC are ______ & _________.
Obstruction or leaks
T or F: a restrictive disease always shows a decrease of DlCO
False, some restrictive diseases do not affect or cause a decrease in DLCO
What is normally given for pulmonary hypertension?
Nitrics
T or F: the number of patients with CF is under estimated?
True
T or F: it’s unusual for post surgery patients to experience decreased lung volumes which mimick restrictive conditions
False
Name a couple of conditions causing decreased lung volumes?
Inflammatory diseases Cardiac disease Neurological neuromuscular Pleural disease Thoracic deformities Fibrotic disease
These types of abnormalities are characterized by decreased compliance, decreased thoracic compliance?
Restrictive disease
T or F: Increased volume = decreased compliance
F; direct relationship exists
Name some common causes of obstruction (6)?
Bronchoconstriction excessive swelling tumors bronchiole collapse increased Raw & decreased flow
If you have a FEV1 value decreased or 44% of predicted how would you classify this patient with no other data?
Obstructive only, moderate
If you patient has an FEV1 of 81? how would they be classified?
Normal
When evaluating pulmonary function test analysis they are based on _________.
Predicted normal values
In order to meet ATS qualifications for acceptable performance standards when performing more than 1 tests they should not differ by more than ______%.
5%
What type of equipment may be used to validate other PFT equipment & it uses volume & time measurements.
Water Sealed Collins
The gold standard of rotor spirometers which measures air flow as it passes through a motor or turbine?
Wrights respirometer
In order to calibrate volume what do you do?
Measure against a 3.0 syringe
When a patient exhales to RV and then inspires 100% O2 they are probably receiving what type of test?
SB N2
What are some factors that may give false results when looking at DLCO? 6 total
Alcohol measurements will decrease DlCO HB, HCT Body position Breath hold time, will increase if not held long enough Patients lung volumes Smoking
When performing tests for DLCO a patient who is a smoker should be instructed not to smoke _________ hrs before the testing.
24 hours
