The Biomechanical Mechanism of Upper Airway Collapse in OSAHS Patients Using Clinical Monitoring Data during Natural Sleep.

Obstructive sleep apnea hypopnea syndrome (OSAHS) is a common sleep disorder characterized by repeated pharyngeal collapse with partial or complete obstruction of the upper airway. This study investigates the biomechanics of upper airway collapse of OSASH patients during natural sleep. Computerized tomography (CT) scans and data obtained from a device installed on OSASH patients, which is comprised of micro pressure sensors and temperature sensors, are used to develop a pseudo three-dimensional (3D) finite element (FE) model of the upper airway. With consideration of the gravity effect on the soft palate while patients are in a supine position, a fluid-solid coupling analysis is performed using the FE model for the two respiratory modes, eupnea and apnea. The results of this study show that the FE simulations can provide a satisfactory representation of a patient's actual respiratory physiological processes during natural sleep. The one-way valve effect of the soft palate is one of the important mechanical factors causing upper airway collapse. The monitoring data and FE simulation results obtained in this study provide a comprehensive understanding of the occurrence of OSAHS and a theoretical basis for the individualized treatment of patients. The study demonstrates that biomechanical simulation is a powerful supplementation to clinical monitoring and evaluation.

Congenital Hairy Polyp Causing Severe Upper Airway Obstruction in a Newborn: A Case Report.

BACKGROUND Hairy polyps are rare tumors mainly comprising fatty tissues covered by skin and hair follicles, with varied localizations and sizes. Early excision of the polyps by surgery is an effective treatment resulting in a permanent cure. We present a case of successful management of severe obstruction of the oropharynx in a newborn who presented with a large mass of congenital hairy polyp. CASE REPORT A vaginally delivered infant, weighing 3 kg, presented immediately after birth with cyanosis symptoms, failure of the first cry, and respiratory distress signs. The newborn was born to a mother with an uneventful pregnancy. Screening tests during the pregnancy reported no congenital anomalies. The newborn's hematological and biochemical test results were normal. After presenting these symptoms, the newborn was immediately intubated and put on a nasogastric feeding tube, which revealed a small portion of a polyp-like mass. A computed tomography (CT) scan further confirmed a large pedunculated mass, measuring 3×2 cm, arising from the soft palate, and obstructing the oropharynx. Histopathological examination confirmed the presence of a hairy polyp. The polyp was wholly removed transorally using the Covidien LigaSure device without the need for endoscopy. This procedure allowed safe extubation, and the baby was discharged home without symptoms 4 days after birth. CONCLUSIONS This case sheds light on the importance of considering hairy polyp in the differential diagnosis of pharyngeal mass with respiratory distress in pediatric patients. This report also describes our experience using the LigaSure surgical device without needing endoscopic visualization to successfully resect the hairy polyp without complications.