| Literature DB >> 28502893 |
Per Larsson1, Björn Bake2, Anita Wallin3, Oscar Hammar4, Ann-Charlotte Almstrand3, Mona Lärstad3, Evert Ljungström5, Ekaterina Mirgorodskaya3, Anna-Carin Olin3.
Abstract
Exhaled particles constitute a micro-sample of respiratory tract lining fluid. Inhalations from low lung volumes generate particles in small airways by the airway re-opening mechanism. Forced exhalations are assumed to generate particles in central airways by mechanisms associated with high air velocities. To increase knowledge on how and where particles are formed, different breathing manoeuvres were compared in 11 healthy volunteers. Particles in the 0.41-4.55μm diameter range were characterised and sampled. The surfactant lipid dipalmitoylphosphatidylcholine (DPPC) was quantified by mass spectrometry. The mass of exhaled particles increased by 150% (95% CI 10-470) for the forced exhalation and by 470% (95% CI 150-1190) for the airway re-opening manoeuvre, compared to slow exhalations. DPPC weight percent concentration (wt%) in particles was 2.8wt% (95%CI 1.4-4.2) and 9.4wt% (95%CI 8.0-10.8) for the forced and the airway re-opening manoeuvres, respectively. In conclusion, forced exhalation and airway re-opening manoeuvres generate particles from different airway regions having different DPPC concentration.Entities:
Keywords: Airway re-opening; Exhaled particles; Forced expiration; Non-invasive technique; PEx; Pulmonary surfactant
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Year: 2017 PMID： 28502893 DOI： 10.1016/j.resp.2017.05.003
Source DB: PubMed Journal: Respir Physiol Neurobiol ISSN： 1569-9048 Impact factor: 1.931