ATS Pulmonary Function Laboratory Manual

ATS Pulmonary Function Laboratory Management & Procedure Manual | 3rd Edition

6. An adjustment for Hb concentration should be done whenever possible (Appendix 1). 7. Valsalva or Mueller maneuvers during the breath-hold alter Dl CO Dl CO by decreasing capillary blood volume. The Mueller maneuver will increase the Dl CO capillary blood volume. 8. Pregnancy (first trimester) has been reported to be associated with an increased Dl CO (14). However, two other studies have reported no change during pregnancy (15, 16). Thus, it is unclear whether Dl CO changes during early pregnancy. 9. Bronchodilators may affect Dl CO (26). The Dl CO report should note if the test was done before or after bronchodilator administration. 10. The choice of reference equations may affect the final interpretation. Each laboratory should select refer- ence equations that are appropriate for the methods used and the population tested. One approach is to test 30–100 normal subjects over a range of ages and compare their results to currently available prediction using least square techniques. This is a critical element because large differences have been observed among different reference equations and among different laboratories (27). 11. The choice of reference equation for the pediatric population has been particularly challenging. As of 2015, . The Valsalva maneuver will decrease the by increasing References 1. Crapo R, Forster RE. Carbon monoxide diffusing capacity. Clin Chest Med 1989;10:187–198. 2. Krogh M. The diffusion of gases through the lungs of man. J Physiol 1915;49:271–300. 3. Forster RE, Cohn JE, Briscoe WA, et al . A modification of the Krogh carbon monoxide breath- holding technique for estimating the diffusing capacity of the lung: A comparison with three other methods. J Clin Invest 1955;34:1417–1426. 4. Ogilvie CM, Forster RE, Blackemore WS, et al . A standardized breath-holding technique for the measurement of the diffusing capacity of the lung for carbon monoxide. J Clin Invest 1957;36:1–17. 5. McGrath MW, Thomson ML. The effect of age, body size and lung volume change on alveolar-capil- lary permeability and diffusing capacity in man. J Physiol 1959;146:572–582. 6. Huang Y-C, MacIntyre NR. Real-time gas analysis improves the measurement of single-breath dif- fusing capacity. Am Rev Respir Dis 1992;146:946–950. 7. Graham BL, Brusasco V, Burgos F, et al. 2017 ERS/ATS Standards for single-breath carbon monoxide uptake in the lung. Eur Respir J 2017;49:1600016. 8. American Thoracic Society. Single-breath carbon monoxide diffusing capacity (transfer factor); Recom- mendations for a standard technique - 1995 update. Am J Respir Crit Care Med 1995;152:2185–2198. 9. American Thoracic Society. Single-breath carbon monoxide diffusing capacity (transfer factor): rec- ommendations for a standard technique. Am Rev Respir Dis 1987;136:1299–1307. 10. Frey TM, Crapo RO, Jensen RL, Elliott CG. Diurnal variation of the diffusing capacity of the lung: is it real? Am Rev Respir Dis 1987;136:1381–1384. 11. Jones RS, Meade F. A theoretical and experimental analysis of anomalies in the estimation of pulmo- nary diffusing capacity by the single breath method. Q J Exp Physiol 1961;46:131–143. 12. Cotes JE. Lung Function. 5th Ed. London, Blackwell Scientific Publications, 1993. the most rigorous equations are those of Kim and colleagues (28). 12. The Global Lung Function Initiative reference values for Dl CO for ages 6 to 90 years of age will become available in 2017 ( see www.lungfunction.org).

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