Protocol - Lung Function - Diffusion Capacity
Protocol Name from Source:This section will be completed when reviewed by an Expert Review Panel.
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 (DLCO) 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 DLCO, 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 [link[www.thoracic.org/statements/pulmonary-function.php|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.
Lung Function Testing: Single-breath carbon monoxide diffusing capacity (DLCO)
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 can be found [link[www.phenx.org/Portals/0/phenx-content/Supplements/SickleCell/WG1/DocumentsForReview/Documents_for_Additional_Information/03_Lung_Function_Diffusion_Capacity.pdf|here]] as well as on the ATS website: [link[www.thoracic.org/statements/resources/pft/pft4.pdf|www.thoracic.org/statements/resources/pft/pft4.pdf]]
Personnel and Training Required
Certified respiratory therapist who is also certified in the proper use of equipment for single-breath carbon monoxide diffusing capacity (DLCO).
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)
|Average time of greater than 15 minutes in an unaffected individual||No|
|Specialized requirements for biospecimen collection||No|
Mode of Administration
Child, Adolescent, Adult, Senior, Pregnancy
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 ([link[www.thoracic.org/|www.thoracic.org/]]) to view other documents in this series that may apply to their area of research.
Also please note, per [link[www.thoracic.org/statements/resources/pft/pft4.pdf|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 (DLCO), the predicted DLCO for the subject, and percent predicted DLCO achieved. Additionally, the alveolar volume (VA) should be obtained and the DLCO/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.
July 30, 2015
DefinitionClinical assessment to determine the capacity of an individual’s lung to exchange gases (e.g., oxygen and carbon dioxide) across the alveolar-capillary interface.
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.
Although there are various methods to measure carbon monoxide diffusing capacity (DLCO) of the lung (such as steady-state, intra-breath, and rebreathing techniques), the single-breath technique is most commonly used worldwide.
|Common Data Elements (CDE)||Lung Function Outcome Score||2806422||CDE Browser|
Process and Review
This section will be completed when reviewed by an Expert Review Panel.
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
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.
|Variable Name||Variable ID||Variable Description||Version||dbGaP Mapping|
|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_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_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_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_Zero_Measurement||PX810301050000||What is the measured gas concentration at zero?||4||N/A|
|PX810301_SingleBreath_CarbonMonoxide_DiffusingCapacity_Concentration_TestGas||PX810301060000||What is the gas concentration of the test gas?||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_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_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_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_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_AlveolarSample||PX810301160100||What is the dead space volume measurement for the alveolar sample?||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_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_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_Quality_Calibration||PX810301200000||Was the calibration test performed with a 'standard subject' (biological control) or simulator?||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_Testing_NewTest||PX810301220000||Was the device tared to zero after the last test?||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_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_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_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_LastCigarette||PX810301270000||What time did the subject smoke his/her last cigarette?||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_SampleGasVolume||PX810301290000||Is the sample gas volume collected between 0.5-1.0L?||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_InspiredCO||PX810301310000||Is the inspired CO around 0.3% of the collected volume?||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_Standardization_Broncodilator||PX810301330000||Was a bronchodilator used?||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_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_Device_CoolGas||PX810301380000||Does the device allow exhaled gases to cool (e.g. volume to contract)?||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_Sex||PX810301400000||What is the sex 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_Race||PX810301420000||What racial/ethnic group does the subject identify with?||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|