Material & Methods
Detailing our single-center experience, this study delves into the
implantation of tracheobronchial stents in four pediatric patients with
intricate airway obstructions. From January 2019 to October 2022,
patients aged 2 to 18 who underwent stent implantation at China Medical
University Children’s Hospital were enrolled. We performed spirometry,
impulse oscillometry, and bronchodilator tests before and two weeks
after stent intervention. Our choice of stent was Bonastent (Standard
SciTech Inc.), a self-expanding silicon-covered stent. Impulse
oscillometry was conducted to gauge respiratory parameters, including
airway resistance at 5 Hz (R5), airway resistance at 20 Hz (R20),
R5-R20, alveolar reactance at 5 Hz (X5), and resonance frequency. The
application of impulse oscillometry offers a window into obstructive
lung disease assessment via resistance measurements. A difference
greater than 0.07 kPaA/(L/s) between R5 and R20 hints at small airway
dysfunction (SAD). Further, R5 exceeding 150% of the reference value
signifies obstructive lung disease. A reduction of 30% of R5 value 15
minutes after 200 mcg of albuterol inhalation would be considered as
positive evidence of airway reversibility. (2). Medcalc 20.118b was used
as statistic software for data analysis.