Introduction: The structure and the neural control of the upper airway have evolved to serve four important physiological functions: 1) respiration 2) deglutition 3) speech and 4) local immunity. The upper airway is collapsible in order to accommodate these functions. During wakefulness, upper airway collapse can be prevented by an increase in pharyngeal neuromuscular tone (1). However, this me...

To determine the combined effect of increased subatmospheric upper airway pressure and withdrawal of phasic volume feedback from the lung on genioglossus muscle activity, the response of this muscle to intermittent nasal airway occlusion was studied in 12 normal adult males during sleep. Nasal occlusion at end expiration was achieved by inflating balloon-tipped catheters located within the port...

BACKGROUND Knowledge regarding normal upper airway anatomy is essential for airway management and is required to prevent malpositioning of endotracheal tubes. We evaluated the length of the upper airway in Korean children and adults who had no abnormality of the upper airway using a fiberoptic bronchoscope. METHODS Eighty seven patients aged 5 to 81 years undergoing noninvasive elective surge...

Clinical signs of upper airway obstruction provide valuable information regarding the degree of airway compromise and the anatomic compartment involved but are not specific to any disease process. The purpose of the diagnostic workup is to determine the extent and nature of the condition. The extent of the physical examination depends on the degree of upper airway obstruction, and complete eval...

BACKGROUND This study investigated the effect of varying concentrations of propofol on upper airway collapsibility and the mechanisms responsible for it. METHODS Upper airway collapsibility was determined from pressure-flow relations at three concentrations of propofol anesthesia (effect site concentration = 2.5, 4.0, and 6.0 mug/ml) in 12 subjects spontaneously breathing on continuous positi...

Laryngomalacia is the most common cause of neonatal stridor, accounting for up to 60% of cases [1]. Less common causes of neonatal stridor include subglottic or tracheal stenosis, or congenital masses of the upper airway. Neonates with an identified congenital etiology of symptomatic upper airway obstruction often have synchronous airway lesions leading to multilevel airway obstruction. These i...