HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Free Full Text (PDF) Free All Versions of this Article: 102/6/2149    most recent 00891.2006v1 Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (2) Citing Articles via Google Scholar Google Scholar Articles by Moreau-Bussière, F. Articles by Praud, J.-P. Search for Related Content PubMed PubMed Citation Articles by Moreau-Bussière, F. Articles by Praud, J.-P.

Laryngeal response to nasal ventilation in nonsedated newborn lambs

Neonatal Respiratory Research Unit, Departments of Pediatrics and Physiology, Université de Sherbrooke, Quebec, Canada

Submitted 11 August 2006 ; accepted in final form 15 February 2007

Although endoscopic studies in adult humans have suggested that laryngeal closure can limit alveolar ventilation during nasal intermittent positive pressure ventilation (nIPPV), there are no available data regarding glottal muscle activity during nIPPV. In addition, laryngeal behavior during nIPPV has not been investigated in neonates. The aim of the present study was to assess laryngeal muscle response to nIPPV in nonsedated newborn lambs. Nine newborn lambs were instrumented for recording states of alertness, electrical activity [electromyograph (EMG)] of glottal constrictor (thyroarytenoid, TA) and dilator (cricothyroid, CT) muscles, EMG of the diaphragm (Dia), and mask and tracheal pressures. nIPPV in pressure support (PS) and volume control (VC) modes was delivered to the lambs via a nasal mask. Results show that increasing nIPPV during wakefulness and quiet sleep led to a progressive disappearance of Dia and CT EMG and to the appearance and subsequent increase in TA EMG during inspiration, together with an increase in trans-upper airway pressure (TUAP). On rare occasions, transmission of nIPPV through the glottis was prevented by complete, active glottal closure, a phenomenon more frequent during active sleep epochs, when irregular bursts of TA EMG were observed. In conclusion, results of the present study suggest that active glottal closure develops with nIPPV in nonsedated lambs, especially in the VC mode. Our observations further suggest that such closure can limit lung ventilation when raising nIPPV in neonates.

thyroarytenoid muscle; cricothyroid muscle; diaphragm; states of alertness; intermittent positive-pressure ventilation

This article has been cited by other articles:

				B. Roy, N. Samson, F. Moreau-Bussiere, A. Ouimet, D. Dorion, S. Mayer, and J.-P. Praud Mechanisms of active laryngeal closure during noninvasive intermittent positive pressure ventilation in nonsedated lambs J Appl Physiol, November 1, 2008; 105(5): 1406 - 1412. [Abstract] [Full Text] [PDF]

				F. H. Andrade Noninvasive ventilation in neonates: the lungs don't like it! J Appl Physiol, November 1, 2008; 105(5): 1385 - 1386. [Full Text] [PDF]

				N. Samson, B. Roy, A. Ouimet, F. Moreau-Bussiere, D. Dorion, S. Mayer, and J.-P. Praud Origins of the inhibiting effects of nasal CPAP on nonnutritive swallowing in newborn lambs J Appl Physiol, October 1, 2008; 105(4): 1083 - 1090. [Abstract] [Full Text] [PDF]