Abstract â–¡ 174

Infantile airway closure is mediated through the Laryngeal Adductor Reflex (LAR). This reflex is the result of a complex sequence of neurologic events. It results in glottic closure with or without a swallow and protects the airway from aspiration of feeds and secretions. Dysfunction of the LAR has been implicated in apnea and apparent life threatening events. Alteration of the LAR may result from change in the sensory stimulus that induces the LAR. Laryngopharyngeal Sensory Stimulation (LPSS) is an objective evaluation of the afferent limb of the laryngeal adductor reflex. During awake flexible laryngoscopy, a calibrated air pulse ranging in intensity from 2.0-10.0 mm Hg is delivered through a flexible laryngoscope (Pentax) to the aryepiglottic fold region of the larynx to induce the laryngeal adductor reflex (LAR). This technique was used in 15 infants and children under 6 months of age with symptoms of upper airway obstruction or apnea with a diagnosis of gastroesophageal reflux (GER) or laryngomalacia. Endoscopic findings demonstrated posterior glottic edema and redundant tissue with erythema. The air pulse intensity required to induce the laryngeal adductor reflex was higher in patients with GER (4.5-10 mm Hg) compared to patients without GER (<4.0 mm Hg) and compared to previously published studies in normal adults (<4.0mm Hg). We have demonstrated that there is an alteration in the afferent limb of the LAR in infants with GER. A plausible mechanism of apnea and airway obstruction in these patients is a functional anesthesia of the larynx with inability to clear a stimulus resulting in tissue edema and airway obstruction. LPSS testing should be considered in the evaluation of all infants with a history of apnea and upper airway obstruction.