Case Report: Vocal cord collapse during phrenic nerve-paced respiration in congenital central hypoventilation syndrome [version 1; referees: 2 approved]

Phrenic nerve pacing can be used to treat congenital central Objective: hypoventilation syndrome (CCHS). We report how the lack of normal vocal cord tone during phrenic paced respiration can result in passive vocal cord collapse and produce obstructive symptoms. We describe a case of passive vocal cord collapse during phrenic Methods: nerve paced respiration in a patient with CCHS. As far as we know, this is the first report of this etiology of airway obstruction. The patient, a 7-year-old with CCHS and normal waking vocal cord movement, continued to require nightly continuous positive airway pressure (CPAP) despite successful utilization of phrenic nerve pacers. On direct laryngoscopy, the patient’s larynx was observed while the diaphragmatic pacers were sequentially engaged. No abnormal vocal cord stimulation was witnessed during engaging of Results: either phrenic nerve stimulator. However, the lack of normal inspiratory vocal cord abduction during phrenic nerve-paced respiration resulted in vocal cord collapse and partial obstruction due to passive adduction of the vocal cords through the Bernoulli effect. Bilateral phrenic nerve stimulation resulted in more vocal cord collapse than unilateral stimulation. The lack of vocal cord abduction on inspiration presents a limit Conclusions: to phrenic nerve pacers. Mark C Domanski ( ) Corresponding author: [email protected] Domanski MC and Preciado DA. How to cite this article: Case Report: Vocal cord collapse during phrenic nerve-paced respiration in 2012, :42 (doi: congenital central hypoventilation syndrome [version 1; referees: 2 approved] F1000Research 1 ) 10.12688/f1000research.1-42.v1 © 2012 Domanski MC and Preciado DA. This is an open access article distributed under the terms of the Copyright: Creative Commons , which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Data Attribution Licence associated with the article are available under the terms of the (CC0 1.0 Public domain Creative Commons Zero "No rights reserved" data waiver dedication). The author(s) declared that no grants were involved in supporting this work. Grant information: No competing interests were disclosed. Competing interests: 01 Nov 2012, :42 (doi: ) First published: 1 10.12688/f1000research.1-42.v1 1