Tidal breathing lung function analysis of wheezing and non-wheezing infants with pneumonia: A retrospective observational study.

To compare lung function in wheezing and non-wheezing infants with pneumonia through tidal breathing analysis and explore the correlation between tidal breathing lung function and clinical characteristics. This retrospective observational study included infants with pneumonia hospitalized in the Affiliated Hospital of Guizhou Medical University between January 2018 and December 2018. Medical records were used to obtain the demographic characteristics, clinical characteristics, tidal breathing lung function results before and after a bronchodilator test, and positive remission rates after the bronchodilator test for each patient. Eighty-six wheezing infants (64 males, aged 6.5 [4.8, 9] months) and 27 non-wheezing infants (18 males, aged 7 [5, 12] months) were included. Non-wheezing infants were more likely to have normal airway function compared to wheezing infants (44.4% vs 23.3%, P = .033). Peak tidal expiration flow/tidal expiratory flow (TEF)25 in wheezing infants was significantly higher than that in non-wheezing infants (162.4 [141.2, 200.7] vs 143.3 [131, 178.8], P = .037). The positive remission rate of tidal inspiratory flow (TIF50)/TEF50 (53.5% vs 29.6%, P = .03) and TEF50 (58.1% vs 33.3%, P = .024) were significantly higher in the wheezing infants compared to non-wheezing infants (P = .03 and P = .024, respectively). Furthermore, respiratory rate, tidal volume, peak expiration flow, TEF25, TEF50, and TEF75 were significantly correlated to the age, height, weight, and platelet counts of infants in both the wheezing and non-wheezing infants (all P < .05). Wheezing infants with pneumonia were more likely to have worse tidal breathing lung function compared to non-wheezing infants with pneumonia. The tidal breathing lung function parameter (respiratory rate, tidal volume, peak expiration flow, TEF25, TEF50, and TEF75) were correlated to the age, height, weight, and platelet counts of both wheezing and non-wheezing infants.