What you can expectBy Mayo Clinic Staff
To do this test, you'll be seated. Your doctor will have you put in a mouthpiece attached with a tube that leads to an electronic measurement device. Next, you'll breathe in for two or three seconds until your lungs are filled with air. Your doctor will then have you exhale steadily so that the air flows out of your lungs at a steady rate. Your doctor may have you watch a computer monitor that registers how much you're breathing out so that you can maintain a steady exhalation. You'll need to repeat the test a few times to confirm your results. The entire test generally takes five minutes or less.
May 09, 2017
- Dweik RA, et al. An official ATS clinical practice guideline: Interpretation of exhaled nitric oxide levels (FENO) for clinical applications. American Journal of Respiratory and Critical Care Medicine. 2011;184:602.
- Lim KG, et al. The use of fraction of exhaled nitric oxide in pulmonary practice. Chest. 2008;133:1232.
- Deykin A, et al. Exhaled nitric oxide analysis. http://www.uptodate.com/home. Accessed Oct. 14, 2013.
- Silkoff PE, et al. ATS/ERS recommendations for standardized procedures for the online and offline measurement of exhaled lower respiratory nitric oxide and nasal nitric oxide. American Journal of Respiratory and Critical Care Medicine. 2005;171:912.
- Dinakar C. Exhaled nitric oxide in pediatric asthma. Current Allergy and Asthma Reports. 2009;9:30.
- Malinovschi A, et al. Exhaled nitric oxide levels and blood eosinophil counts independently associate with wheeze and asthma events in National Health and Nutrition Examination Survey subjects. Journal of Allergy and Clinical Immunology. 2013;132:821.