Assessing and accessing the small airways; implications for asthma management.
Despite the wealth of experience in the management of asthma, the disease remains inadequately controlled in some patients, who face long-term respiratory impairment and disability. The disease has been characterised as an inflammatory condition affecting first the larger airways and eventually the smaller airways, but there is evidence that peripheral airway involvement defines a particular and more severe phenotype of asthma. For this reason, assessing functional and biological parameters reflective of small airways involvement is important prognostically. No assessment method is universally and directly representative of peripheral airway function, but the traditional spirometric tests, including vital capacity, residual volume and forced vital capacity, are somewhat correlated with this function; useful methods for further assessment include the single-breath nitrogen wash-out test, impulse oscillometry, nitrous oxide and exhaled breath concentrate measurements, as well as computed tomography to reflect air trapping and response to treatment. Formulation advancements have made for easier treatment access to the smaller airways, with the new extrafine formulations resulting in better asthma control compared with non-extrafine formulations.
Biomedical Department of Internal and Specialist Medicine (DIBIMIS), Section of Pneumology, University of Palermo, via Trabucco 180, 90146 Palermo, Italy. nicola.scichilone@unipa.it
Nicola
N
Scichilone
Marco
M
Contoli
Davide
D
Paleari
Pietro
P
Pirina
Andrea
A
Rossi
Claudio Maria
CM
Sanguinetti
Pierachille
P
Santus
Matteo
M
Sofia
Nicola
N
Sverzellati
D001249:Asthma / Q000188:drug therapy* / Q000209:etiology / Q000503:physiopathology*; D001944:Breath Tests; D005541:Forced Expiratory Volume; D006801:Humans; D009569:Nitric Oxide / Q000032:analysis; D012129:Respiratory Function Tests; D014057:Tomography, X-Ray Computed; D014797:Vital Capacity
D009569:Nitric Oxide