The following is a summary of “Oscillatory Mechanics Response to Inhaled Bronchodilators in Very Preterm Infants: A Retrospective Study,” published in the December 2022 issue of Pediatrics by Rigotti, et al.


For a study, researchers sought to determine the forced oscillation technique’s (FOT) short-term repeatability, evaluate the lung function response to bronchodilators (BDs) using FOT, and support the idea that only a small percentage of extremely preterm newborns exhibit a change in lung mechanics in response to BD.

A retrospective analysis of FOT-measured respiratory system reactance and resistance was conducted (Fabian HFOi). BD responsiveness was evaluated using a separate data set, which included 38 measures in 18 newborns, and the measurement of short-term repeatability was examined using 43 patients 60 times. The difference between two measurements taken 15 minutes apart was used to compute the coefficient of repeatability. They could evaluate the BD responsiveness by monitoring respiratory system resistance and reactance before and 15 minutes after giving 200 mcg/kg of nebulized salbutamol. A rise in respiratory system reactance or resistance that was more than the determined coefficient of repeatability was considered a positive response.

For respiratory system reactance, the coefficient of repeatability was 6.3 cmH2O∗s/L (21%), whereas it was 7.5 cmH2O∗s/L (21%). Respiratory system reactance increased considerably (from −32.0 [−50.2, −24.4] to −27.9 [−38.1, −22.0] cmH2O∗s/L, P< .001), although overall respiratory system resistance did not alter much after BD administration. On 13 (34%) occasions, changes in respiratory system reactance or resistance after BD were bigger than the determined coefficient of repeatability in 8 babies (44%) than on the baseline.

They established a threshold to evaluate preterm infants’ BD response using FOT. Finally, they hypothesized that FOT might be used to evaluate and tailor therapy with BD.

Reference: jpeds.com/article/S0022-3476(22)00708-9/fulltext