[Pulmonary surfactant and lower airway function]

The effect of pulmonary surfactant on small airway function was evaluated in 32 patients undergoing lobectomy or pneumonectomy due to local lung diseases. Surfactant of lung tissue obtained from the surgical specimens and airway lining surfactant obtained from bronchoalveolar lavage were measured. Before surgery, small airway function testing including CV/VC, CC/TLC, delta N2/L,V50 and V25 were measured in each patient. They were then divided into two groups: group I with normal function and group II abnormal function. The results showed that pulmonary surfactant in bronchoalveolar lavage fluid was statistically less in group II than in group I, whereas that in the lung tissue had no significantly difference between the two groups. It is therefore conceivable that the decrease of small airway function, besides as a result of its structure or pathologic abnormalities, could be due to the decrease in airway surfactant as well.