[Studies of pulmonary function in the post-virosis period].

The pulmonary function was studied in 21 patients with viral diseases of the lungs 10 to 18 days after the acute episode. In 14 cases all the parameters tested were normal; in 7 cases the alterations found led to a diagnosis of obstructive syndrome of the smaller airways (increased intrapulmonary helium mixture time, increased expired CO2 alveolar slope and residual volume). The alterations were again found on repeating the tests after 6--10 months. The various mechanisms that might cause obstruction are discussed (persistent inflammation, increased tonus of the bronchiolar musculature, hypersecretion in the smaller airways, alteration of the surfactant). In conclusion the authors raise the question of whether the obstructive alterations following pulmonary viral diseases might not be one of the etiopathogenic factors of chronic, obstructive bronchopneumopathy.