Atelectasis is a significant risk factor for the development of pneumonia, especially in pediatric populations more prone to alveolar collapse or those who may have weakened muscular tone. The Metaneb system is a pneumatic, noninvasive physiotherapy technique that delivers chest high-frequency oscillations. Chest high-frequency oscillations have been shown to enhance mucociliary clearance of secretions and help resolve patchy atelectasis. This report describes the case of a 17-year-old female patient who developed significant left-sided atelectasis after extubation and was effectively managed with complete resolution of her atelectasis with the Metaneb system, obviating the need for reintubation.