We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Flow dependency and off-line measurement of exhaled NO in children.
- Authors
van Amsterdam, J. G. C.; Zanen, P.; Somer, S.; van Loveren, H.; Opperhuizen, A.; Steerenberg, P. A.
- Abstract
Levels of exhaled nitric oxide (eNO) are flow-dependent, and the choice of an optimal flow rate for off-line and on-line eNO measurement has raised much debate. Recently, a flow rate of 50 ml/s was recommended, but children younger than 5–6 years are not capable of stabilizing their expiratory flow at low flow rates. The power of off-line eNO values to discriminate between normal and atopic children was therefore evaluated at different exhalation flow rates. At flow rates of both 8.3 ml/s and of 350 ml/s, children (8–12 years) sensitive to house dust mite have two-fold higher eNO values (p < 0.001) as compared with children lacking such a sensitivity. The power of eNO to discriminate between normal and atopic subjects was similar at the two flow rates (no difference in AUC of receiver operation curves, p = 0.89). All children from 4.5 to 5 years of age (n = 29) could perform a single off-line exhalation manoeuvre at high (>350 ml/s) but not at low (8.3 ml/s) flow rates. At high exhalation flow rate, eNO was 7.1 ± 2.4 (mean ± SD) median, 6.5 p.p.b. with a mean variation coefficient of 5.5%. Depending on their developmental level, about half of the younger children (35–46 months of age) could perform an off-line exhalation manoeuvre at high flow rate with good reproducibility (mean variation coefficient of 6.6%). It is concluded that an exhalation flow rate of 350 ml/s is feasible to determine off-line eNO-values in children from 3.5 years of age, and that this high flow rate does not compromise the power of eNO to detect allergic disease.
- Subjects
NITRIC oxide; ALLERGIES; STANDARD deviations
- Publication
Pediatric Allergy & Immunology, 2003, Vol 14, Issue 4, p266
- ISSN
0905-6157
- Publication type
Article
- DOI
10.1034/j.1399-3038.2003.00035.x