Diagnostic and Therapeutic Applications of Laryngeal Point-of-care Ultrasound in Paradoxical Vocal Cord Movement

Paradoxical vocal cord motion (PVCM) in pediatric patients is a cause of stridor and respiratory distress wherein vocal cords adduct (close) with inhalation and, at times, adduct with exhalation, causing pronounced stridor and respiratory distress. Symptoms respond to specialized breathing exercises guided by a speech therapist with expertise in paradoxical vocal cord motion. Frequently, because of poor response to pharmaceutical therapies, children often experience overtreatment in attempts to curtail respiratory symptoms. PVCM can be difficult to distinguish from other etiologies (eg, asthma or croup) without flexible laryngoscopy or pulmonary function tests. However, laryngoscopy is invasive, and both require equipment and specialists not readily available in many pediatric emergency departments. Because of the episodic nature of PVCM, outpatient diagnostic testing can be inconclusive if an exacerbation has resolved by the time of testing. Visualization of the vocal cords at the time of presentation is key to the diagnosis and timely treatment of PVCM. Although there is pediatric literature reporting the utility of laryngeal Point-of-care Ultrasound (POCUS) to noninvasively visualize vocal cord paralysis, there is scant literature examining the utility of POCUS in the diagnosis and monitoring of PVCM. Here, we present 3 cases where we used laryngeal POCUS in the pediatric emergency department to capture PVCM with a video laryngoscopy correlation. Case Presentation.