Protocol - Lung Function - Diffusion Capacity

Description:

The American Thoracic Society (ATS) and the European Respiratory Society (ERS) Task Force recommendations for standardisation of the single-breath determination of carbon monoxide uptake in the lung outlines principles for performing high-quality single-breath carbon monoxide diffusing capacity (D_LCO) testing. Topics covered include necessary equipment (e.g., gas analyzers), standardization issues associated with single-breath testing technique, and how to evaluate the quality of measurements of D_LCO, calculations, definitions and abbreviations.

These recommendations for the single-breath determination of carbon monoxide uptake in the lung are part of a series of recommendations by the ATS/ERS Task Force for the standardization of lung function testing, which can be found on the ATS website at www.thoracic.org/statements/pulmonary-function.php. Detailed information regarding patient preparation is included in the general considerations section of the recommendations for lung function testing in this series.

Protocol:

Lung Function Testing: Single-breath carbon monoxide diffusing capacity (D_LCO)

Protocol Name from Source:

This section will be completed when reviewed by an Expert Review Panel.

Availability:

Publicly available

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Personnel and Training Required

Certified respiratory therapist who is also certified in the proper use of equipment for single-breath carbon monoxide diffusing capacity (D_LCO).

Equipment Needs

A source of test gas (such as bag-in-box, spirometer, compressed gas cylinder)

A method for measuring inspired and expired volume over time (such as spirometers with kymographs, pneumotachometers near the mouthpiece or near a bag-in-box)

Gas analysers (single-sample analysers or continuous high-speed analysers)

Requirements

Requirement Category	Required
Major equipment	Yes
Specialized training	Yes
Specialized requirements for biospecimen collection	No
Average time of greater than 15 minutes in an unaffected individual	No

Mode of Administration

Clinical assessment

Life Stage:

Child, Adolescent, Adult, Senior, Pregnancy

Participants:

Individuals age 8 years old and older.

Specific Instructions:

A comprehensive evaluation of lung function requires investigation of various aspects of the lung, such as diffusion capacity and lung volume. Hence, the American Thoracic Society (ATS) and the European Respiratory Society (ERS) Task Force have published a series of documents regarding pulmonary function testing. The Sickle Cell Disease: Cardiovascular, Pulmonary, and Renal Working Group recommends researchers access the ATS website (www.thoracic.org/) to view other documents in this series that may apply to their area of research.

Also please note, per www.thoracic.org/statements/resources/pft/pft4.pdf: If clinically acceptable, the subject should not breathe supplemental oxygen for 10 minutes prior to a standard test.

At least 4 minutes should be allowed between tests to allow an adequate elimination of test gas from the lungs. The subject should remain seated during this interval. In patients with obstructive airway disease, a longer period (e.g., 10 minutes) should be considered.

The average of at least two acceptable tests should be reported (i.e., outliers excluded).The report should always include the unadjusted measured carbon monoxide diffusing capacity (D_LCO), the predicted D_LCO for the subject, and percent predicted D_LCO achieved. Additionally, the alveolar volume (VA) should be obtained and the D_LCO/VA (predicted and percent predicted) should be reported. Any adjustments (e.g., for Hb, COHb, PI, or O₂,) should also be reported along with the data used to make the adjustment.

Selection Rationale

Although there are various methods to measure carbon monoxide diffusing capacity (D_LCO) of the lung (such as steady-state, intra-breath, and rebreathing techniques), the single-breath technique is most commonly used worldwide.

Language

English

Standards

Standard	Name	ID	Source
Common Data Elements (CDE)	Lung Function Outcome Score	2806422	CDE Browser

Derived Variables

None

Process and Review

This section will be completed when reviewed by an Expert Review Panel.

Source

MacIntyre, N., Crapo, R. O., Viegi, G., Johnson, D.C., van der Grinten, C.P.M., Brusasco, V., Burgos, F., Casaburi, R., Coates, A., Enright, P., Gustafsson, P., Hankinson, J., Jensen, R., McKay, R., Miller, M.R., Navajas, D., Pedersen, O.F., Pellegrino, R. & Wanger, J. (2005). Standardisation of the single-breath determination of carbon monoxide uptake in the lung. European Respiratory Journal, 26, 720-735. doi:10.1183/09031936.05.00034905

General References

Arteta, M., Campbell, A., Nouraie, M., Rana, S., Onyekwere, O. C., Ensing, G., Sable, C., Dham, N., Darbari, D., Luchtman-Jones, L., Kato, G. J., Gladwin, M. T., Castro, O. L., Minniti, C. P., & Gordeuk, V. R. (2014). Abnormal pulmonary function and associated risk factors in children and adolescents with sickle cell anemia. Journal of Pediatric Hematology/Oncology, 36(3), 185-189.

Lunt, A., Desai, S. R., Wells, A. U., Hansell, D. M., Mushemi, S., Melikian, N., Shah, A. M., Thein, S. L., & Greenough, A. (2014). Pulmonary function, CT and echocardiographic abnormalities in sickle cell disease, Thorax 69(8), 746-751.

Protocol ID:

810301

Variables:

Export Variables

Variable Name	Variable ID	Variable Description	Version	dbGaP Mapping
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Concentration_TestGas	PX810301060000	What is the gas concentration of the test gas?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_DeadSpace_Adult	PX810301170000	For adults, is the dead space volume consisting of the volume from the valve, filter, and mouthpiece under 0.35 Liters?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_DeadSpace_AlveolarSample	PX810301160100	What is the dead space volume measurement for the alveolar sample?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_DeadSpace_Volume	PX810301150100	What is the dead space volume measurement for the inspired test gas?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_DeadSpace_VolumeMetric	PX810301150200	How is this metric used in the data-computation above?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_DeadSpace_VolumeMetric2	PX810301160200	How is this metric used in the data-computation above?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Device_CoolGas	PX810301380000	Does the device allow exhaled gases to cool (e.g. volume to contract)?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Device_RemoveCo2	PX810301360000	Does the device remove CO2 from the exhaled gas?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Device_RemoveH2o	PX810301370000	Does the device remove H20 from the exhaled gas?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Equipment_CalibratedAccuracy	PX810301040100	Is the device calibrated to accurately detect the exhaled carbon monoxide and the tracer gas concentrations, which is calculated between the inhaled (test gas concentrations) and zero measurement (no CO or tracer gas present in the device)?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Equipment_CalibratedDeviations	PX810301040200	If so, are the deviations from the true measurement within 0.5% of the full scale? (for example, if 0.3% CO is used for the test gas, then the maximum error on any dilution should be no more than +/- 0.0015%)	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Equipment_CalibratedVolume	PX810301030000	Regardless of the method being used, does the device maintain the required volume accuracy, regardless of the gas mixture, direction of gas flow (e.g. inhaled or exhaled), or pulsatile flow pattern?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Equipment_Method	PX810301020100	Which of the following best describes the method for measuring inspired and expired volumes over time?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Equipment_Method_Other	PX810301020200	Which of the following best describes the method for measuring inspired and expired volumes over time? Other	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Equipment_Regulator	PX810301110100	Is a demand-flow regulator being used on a compressed test gas cylinder?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Equipment_Resistance	PX810301110200	If no, is the circuit resistance of the device <1.5 cm*H20/L/s at 6 L/s flow?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Equipment_Resistance2	PX810301110300	If yes, is the circuit resistance of the device <10cm H20 at 6L/s inspiratory flow?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Equipment_Timing	PX810301120000	Is the timing device accurate to within 1% (100ms over 10s)?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Equipment_TimingTechnique	PX810301130000	What timing technique was used for calibration and/or testing?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_InspiredCO	PX810301310000	Is the inspired CO around 0.3% of the collected volume?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_MeasuredConcentration_TestGas	PX810301070000	What is the measured gas concentration of the test gas?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Observed_Drift	PX810301080000	Is significant drift observed over the time scale of the test (~30 sec)?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Quality_Accuracy	PX810301210100	Within the last 3 months, was the accuracy of the measured gas readings assessed?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Quality_AccuracyDate	PX810301210200	If no, what is today's date (test date)?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Quality_Calibration	PX810301200000	Was the calibration test performed with a 'standard subject' (biological control) or simulator?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Quality_Leaks	PX810301180000	Within the last week, was the device tested to be leak-free?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Quality_VolumeCalibration	PX810301190000	Was the volume calibration test with the 3L syringe performed?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_ReadingStability_CO	PX810301090000	Is the reading stable +/- 0.001% absolute for CO?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_ReadingStability_Tracer	PX810301100000	Is the reading stable +/- 0.5% of the full scale reading for the tracer gas?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Results_Carboxyhemoglobin	PX810301430000	Are carboxyhemoglobin levels < 2%? If not, needs to be considered in interpretation	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Standardization	PX810301230000	Did the subject breathe supplemental oxygen for 10 min prior to this test?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Standardization_Broncodilator	PX810301330000	Was a bronchodilator used?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Standardization_Exercise	PX810301240100	Was the subject involved in any exercise prior to this test?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Standardization_ExerciseIntensity	PX810301240200	If so, please describe the intensity level of the exercise.	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Standardization_LastCigarette	PX810301270000	What time did the subject smoke his/her last cigarette?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Standardization_SampleGasVolume	PX810301290000	Is the sample gas volume collected between 0.5-1.0L?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Standardization_SubjectDemonstration	PX810301260000	Has a demonstration of the manuevers involved in the test and instructions been provided to the subject?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Standardization_Supine	PX810301250100	Was the subject in a supine position prior to this test?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Standardization_SupineDuration	PX810301250200	If so, please provide the duration of the patient in the supine position?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Standardization_TotalExhalation	PX810301280100	What length of time did the subject need for total exhalation?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Standardization_TotalExhalationPlus	PX810301280200	If total exhalation time > 4sec, please note the expiratory time in seconds	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Standardization_TracerType	PX810301300100	What type of tracer gas was used?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Standardization_TracerTypeOther	PX810301300200	What type of tracer gas was used? Other	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Subject_Age	PX810301390000	What is the age of the subject?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Subject_Height	PX810301410000	What is the height of the subject?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Subject_Oad	PX810301320100	Does the subject have obstructive airway disease?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Subject_OadRest	PX810301320200	If so, were at least 10 minutes allowed between tests?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Subject_Race	PX810301420000	What racial/ethnic group does the subject identify with?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Subject_Rest	PX810301340000	Were at least 4 minutes allowed between tests?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Subject_Seated	PX810301350000	Did the subject remain seated during that interval?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Subject_Sex	PX810301400000	What is the sex of the subject?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_TestGas	PX810301010100	Which of the following best describes the source of test gas?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_TestGasOther	PX810301010200	Which of the following best describes the source of test gas? Other	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Testing_NewTest	PX810301220000	Was the device tared to zero after the last test?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Timing_AutomatedComputation	PX810301140100	Does the timing equipment rely on automated data computation?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Timing_AutomatedComputationAccuracy	PX810301140200	If so, how accurate is the breath-hold time computation?	4	N/A
PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Zero_Measurement	PX810301050000	What is the measured gas concentration at zero?	4	N/A

Research Domain Information

Measure Name:

Lung Function - Diffusion Capacity

Release Date:

July 30, 2015

Definition

Clinical assessment to determine the capacity of an individual’s lung to exchange gases (e.g., oxygen and carbon dioxide) across the alveolar-capillary interface.

Purpose

This measure is used to assess the structural and functional properties of the lung and can detect and quantify symptoms associated with conditions that impact the lung, such as sickle cell disease, cystic fibrosis, and obstructive airways disease.

Keywords

Lung function, lung volume, lung physiology, diffusion capacity, D_LCO, functional residual capacity, FRC, sickle cell disease, SCD, emphysema, cystic fibrosis, CF, asbestosis, lupus, arthritis, smoking, sarcoidosis, carbon monoxide, obstructive airway disease, pulmonary, asthma, sleep apnea, breathing