Transnasopharyngeal positive pressure ventilation during balloon dilation of severe subglottic stenosis in a low-weight infant: a case report.

BACKGROUND: Acquired subglottic stenosis (ASGS) is a significant cause of pediatric airway obstruction and presents various anesthetic challenges due to the complexities of altered airway anatomy. While balloon dilation serves as a first-line minimally invasive intervention, shared airway management between surgeons and anesthesiologists requires meticulous coordination. This case report demonstrates the successful implementation of nasopharyngeal airway-assisted positive pressure ventilation during balloon dilation in a critically ill infant with grade III ASGS. This approach proposes a new ventilation strategy for complex airway procedures. CASE PRESENTATION: A 3.2 kg, 3-month-old male infant presented with progressive respiratory failure secondary to Cotton-Myer grade III ASGS. Following multidisciplinary consensus, emergency balloon dilation was performed under general anesthesia with tracheostomy contingency planning. Initial ventilation attempts using a laryngeal mask proved inadequate, causing surgical field obstruction. Transitioning to a nasopharyngeal airway connected to the anesthesia machine in pressure-controlled ventilation mode successfully maintained adequate gas exchange (SpO₂ 95 ~ 100%).The procedure was completed successfully without hemodynamic compromise or airway reflexes, ultimately avoiding tracheostomy. Postoperative recovery was uneventful, with the patient returning to pediatric respiratory intensive care unit for continued respiratory support. CONCLUSION: Using a nasopharyngeal airway assisted positive pressure ventilation can effectively maintain oxygenation and surgical access during pediatric ASGS interventions, proposing a novel ventilation strategy for complex airway procedures. While demonstrating procedural feasibility in this critical scenario, larger-scale prospective studies are required to validate its efficacy and safety profile across varying stenosis severities.