Laryngeal muscle response to phasic and tonic upper airway pressure and flow.
Stella, M. H., and S. J. England.
Department of Pediatrics, Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey, New Brunswick 08903; and Department of Biomedical Engineering, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854
APStracts 8:0277A, 2001.
The hypothesis that respiratory modulation due to upper airway (UA) pressure and flow is dependent on stimulus modality and respiratory phase-specific activation was assessed in anesthetized, tracheotomized, spontaneously breathing piglets. Negative pressure and flow applied to the isolated UA at room or body temperature during inspiration only enhanced posterior crycoarytenoid muscle activity from that present without UA pressure and flow (baseline) by 15-20%. Time shifting the onset of UA flow relative to tracheal flow decreased this enhancement. The same enhancement was observed with oscillatory or constant airflow. UA positive pressure and flow at room or body temperature applied during expiration only enhanced thyroarytenoid muscle activity from baseline by 50-160%. The same enhancement was observed with oscillatory or constant airflow at body temperature. Constant positive pressure and flow enhanced thyroarytenoid muscle activity more than oscillatory pressure and flow at room temperature. We conclude that the respiratory modulation of UA afferents is processed in a phase-specific fashion and is dependent on stimulus modality (tonic vs. phasic).
Received 31 August 2000; accepted in final form 3 April 2001
APS Manuscript Number A837-0.
Article publication pending J Appl Physiol
ISSN 1080-4757 Copyright 2001 The American Physiological Society.
Published in APStracts on 18 June 2001