Extended NO analysis applied to patients with COPD, allergic asthma and allergic rhinitis.
The recommended method to measure exhaled nitric oxide (NO) cannot reveal the source of NO production. We applied a model based on the classical Fick's first law of diffusion to partition NO in the lungs. The aim was to develop a simple and robust solution algorithm with a data quality control feature, and apply it to patients with known alterations in exhaled NO. Subjects with allergic rhinitis, allergic asthma, chronic obstructive pulmonary disease (COPD) smokers and controls were investigated. NO was measured at three expiratory flow rates. An iteration method was developed to partition NO. The airway tissue content of NO was increased in asthma, 144 +/- 80 ppb (P = 0.04) and decreased in smokers, 56 +/- 36 ppb (P = 0.02). There was no difference between subjects with rhinitis, 98 +/- 40 ppb and controls, 98 +/- 44 ppb. The airway transfer rate was increased in allergic asthma and allergic rhinitis, 12 +/- 4 vs. 12 +/- 5 ml sec(-1), compared to controls, 8 +/- 2 ml sec(-1) (P < 0.001). The alveolar levels were no different from controls, 2 +/- 1 ppb. In COPD the alveolar levels were increased, 4 +/- 2 ppb (P < 0.001). Extended NO analysis reveals from where in the respiratory system NO is generated. Hence, this new test can be added to the tools the physician has for the diagnosis and treatment of patients with respiratory disorders.
Högman
M
M
Department of Medical Sciences, Uppsala University, Sweden. marieann.hogman@medcellbiol.uu.se
Holmkvist
T
T
Wegener
T
T
Emtner
M
M
Andersson
M
M
Hedenström
H
H
Meriläinen
P
P
D000280:Administration, Inhalation; D000328:Adult; D000368:Aged; D000465:Algorithms; D001249:Asthma / Q000188:drug therapy / Q000378:metabolism; D001944:Breath Tests; D016022:Case-Control Studies; D005938:Glucocorticoids / Q000627:therapeutic use; D006801:Humans; D006967:Hypersensitivity / Q000188:drug therapy / Q000378:metabolism*; D008168:Lung / Q000378:metabolism*; D008875:Middle Aged; D008954:Models, Biological; D009569:Nitric Oxide / Q000032:analysis*; D010865:Pilot Projects; D029424:Pulmonary Disease, Chronic Obstructive / Q000188:drug therapy / Q000378:metabolism*; D015203:Reproducibility of Results; D012221:Rhinitis, Allergic, Perennial / Q000188:drug therapy / Q000378:metabolism; D012907:Smoking / Q000378:metabolism
D005938:Glucocorticoids; D009569:Nitric Oxide