Upper airway pressures during breathing: A comparison of normal and nasally incompetent subjects with modeling studies

We recently showed respiratory-related coactivation of both extrinsic and intrinsic tongue muscles in the rat. Here, we test the hypothesis that intrinsic tongue muscles contribute importantly to changes in velopharyngeal airway volume. Spontaneously breathing anesthetized rats were placed in a MRI scanner. A catheter was placed in the hypopharynx and connected to a pressure source. Axial and sagittal images of the velopharyngeal airway were obtained, and the volume of each image was computed at airway pressures ranging from +5.0 to −5.0 cmH2O. We obtained images in the hypoglossal intact animal (i.e., coactivation of intrinsic and extrinsic tongue muscles) and after selective denervation of the intrinsic tongue muscles, with and without electrical stimulation. Denervation of the intrinsic tongue muscles reduced velopharyngeal airway volume at atmospheric and positive airway pressures. Electrical stimulation of the intact hypoglossal nerve increased velopharyngeal airway volume; however, when stimulation was repeated after selective denervation of the intrinsic tongue muscles, the increase in velopharyngeal airway volume was significantly attenuated. These findings support our working hypothesis that intrinsic tongue muscles play a critical role in modulating upper airway patency.

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Genioglossal length and EMG responses to static upper airway pressures during hypercapnia in goats

Respiration Physiology ◽

10.1016/s0034-5687(01)00253-5 ◽

2001 ◽

Vol 127 (2-3) ◽

pp. 227-239 ◽

Cited By ~ 6

Author(s):

Michael J Brennick ◽

Richard A Parisi ◽

Sandra J England

Keyword(s):

Upper Airway ◽

Airway Pressures

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Use of computational fluid dynamics to compare upper airway pressures and airflow resistance in brachycephalic, mesocephalic, and dolichocephalic dogs

The Veterinary Journal ◽

10.1016/j.tvjl.2019.105392 ◽

2019 ◽

Vol 253 ◽

pp. 105392 ◽

Cited By ~ 1

Author(s):

R. Fernández-Parra ◽

P. Pey ◽

L. Zilberstein ◽

M. Malvè

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Upper Airway ◽

Airflow Resistance ◽

Airway Pressures

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Effects of respiratory drive on upper airways in sleep apnea patients and normal subjects

Journal of Applied Physiology ◽

10.1152/jappl.1989.67.3.973 ◽

1989 ◽

Vol 67 (3) ◽

pp. 973-979 ◽

Cited By ~ 32

Author(s):

F. Series ◽

Y. Cormier ◽

M. Desmeules ◽

J. La Forge

Keyword(s):

Sleep Apnea ◽

Airway Resistance ◽

Upper Airway ◽

Normal Subjects ◽

Base Line ◽

Respiratory Drive ◽

Upper Airway Resistance ◽

Co2 Rebreathing ◽

Airway Pressures ◽

Line Level

We compared the changes in nasal and pharyngeal resistance induced by modifications in the central respiratory drive in 8 patients with sleep apnea syndrome (SAS) with the results of 10 normal men. Upper airway pressures were measured with two low-bias flow catheters; one was placed at the tip of the epiglottis and the other above the uvula. Nasal and pharyngeal resistances were calculated at isoflow. During CO2 rebreathing and during the 2 min after maximal voluntary hyperventilation, we continuously recorded upper airway pressures, airflow, end-tidal CO2, and the mean inspiratory flow (VT/TI); inspiratory pressure generated at 0.1 s after the onset of inspiration (P0.1) was measured every 15–20 s. In both groups upper airway resistance decreased as P0.1 increased during CO2 rebreathing. When P0.1 increased by 500%, pharyngeal resistance decreased to 17.8 +/- 3.1% of base-line values in SAS patients and to 34.9 +/- 3.4% in normal subjects (mean +/- SE). During the posthyperventilation period the VT/TI fell below the base-line level in seven SAS patients and in seven normal subjects. The decrease in VT/TI was accompanied by an increase in upper airway resistance. When the VT/TI decreased by 30% of its base-line level, pharyngeal resistance increased to 319.1 +/- 50.9% in SAS and 138.5 +/- 4.7% in normal subjects (P less than 0.05). We conclude that 1) in SAS patients, as in normal subjects, the activation of upper airway dilators is reflected by indexes that quantify the central inspiratory drive and 2) the pharyngeal patency is more sensitive to the decrease of the central respiratory drive in SAS patients than in normal subjects.

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Laryngeal Manifestations of Autoimmune Diseases

Perspectives of the ASHA Special Interest Groups ◽

10.1044/2020_persp-19-00168 ◽

2020 ◽

Vol 5 (2) ◽

pp. 439-456

Author(s):

Jenny L. Pierce

Keyword(s):

Autoimmune Disease ◽

Autoimmune Diseases ◽

Patient Outcomes ◽

Correct Diagnosis ◽

Upper Airway ◽

Clinical Implications ◽

Laryngeal Function ◽

The Past ◽

Referral Practices ◽

Timely Referral

Purpose This review article provides an overview of autoimmune diseases and their effects on voice and laryngeal function. Method A literature review was conducted in PubMed. Combinations of the following keywords were used: “autoimmune disease and upper airway,” “larynx,” “cough,” “voice,” “dysphonia,” and “dyspnea.” Precedence was given to articles published in the past 10 years due to recent advances in this area and to review articles. Ultimately, 115 articles were included for review. Results Approximately 81 autoimmune diseases exist, with 18 of those highlighted in the literature as having laryngeal involvement. The general and laryngeal manifestations of these 18 are discussed in detail, in addition to the clinical implications for a laryngeal expert. Conclusions Voice, breathing, and cough symptoms may be an indication of underlying autoimmune disease. However, these symptoms are often similar to those in the general population. Appropriate differential diagnosis and timely referral practices maximize patient outcomes. Guidelines are provided to facilitate correct diagnosis when an autoimmune disease is suspected.

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Distraction Osteogenesis in the Treatment of Craniofacial Anomalies: Applications and Outcomes

Perspectives of the ASHA Special Interest Groups ◽

10.1044/2020_persp-20-00055 ◽

2020 ◽

Vol 5 (6) ◽

pp. 1469-1481 ◽

Cited By ~ 1

Author(s):

Joseph A. Napoli ◽

Carrie E. Zimmerman ◽

Linda D. Vallino

Keyword(s):

Distraction Osteogenesis ◽

Bone Growth ◽

Upper Airway ◽

Craniofacial Anomalies ◽

Craniofacial Skeleton ◽

Facial Skeleton ◽

Psychosocial Impairment ◽

And Function ◽

Correct Structure

Purpose Craniofacial anomalies (CFA) often result in growth abnormalities of the facial skeleton adversely affecting function and appearance. The functional problems caused by the structural anomalies include upper airway obstruction, speech abnormalities, feeding difficulty, hearing deficits, dental/occlusal defects, and cognitive and psychosocial impairment. Managing disorders of the craniofacial skeleton has been improved by the technique known as distraction osteogenesis (DO). In DO, new bone growth is stimulated allowing bones to be lengthened without need for bone graft. The purpose of this clinical focus article is to describe the technique and clinical applications and outcomes of DO in CFA. Conclusion Distraction can be applied to various regions of the craniofacial skeleton to correct structure and function. The benefits of this procedure include improved airway, feeding, occlusion, speech, and appearance, resulting in a better quality of life for patients with CFA.

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Swallow Pattern Generator Reconfiguration of the Respiratory Neural Network

Perspectives on Swallowing and Swallowing Disorders (Dysphagia) ◽

10.1044/sasd18.1.3 ◽

2009 ◽

Vol 18 (1) ◽

pp. 3-12

Author(s):

Andrea Vovka ◽

Paul W. Davenport ◽

Karen Wheeler-Hegland ◽

Kendall F. Morris ◽

Christine M. Sapienza ◽

...

Keyword(s):

Behavioral Control ◽

Upper Airway ◽

Pattern Generator ◽

Breathing Patterns ◽

Motor Patterns ◽

Control Assembly ◽

Pharyngeal Swallow ◽

Laryngeal Vestibule ◽

Lower Airways ◽

Swallow Apnea

Abstract When the nasal and oral passages converge and a bolus enters the pharynx, it is critical that breathing and swallow motor patterns become integrated to allow safe passage of the bolus through the pharynx. Breathing patterns must be reconfigured to inhibit inspiration, and upper airway muscle activity must be recruited and reconfigured to close the glottis and laryngeal vestibule, invert the epiglottis, and ultimately protect the lower airways. Failure to close and protect the glottal opening to the lower airways, or loss of the integration and coordination of swallow and breathing, increases the risk of penetration or aspiration. A neural swallow central pattern generator (CPG) controls the pharyngeal swallow phase and is located in the medulla. We propose that this swallow CPG is functionally organized in a holarchical behavioral control assembly (BCA) and is recruited with pharyngeal swallow. The swallow BCA holon reconfigures the respiratory CPG to produce the stereotypical swallow breathing pattern, consisting of swallow apnea during swallowing followed by prolongation of expiration following swallow. The timing of swallow apnea and the duration of expiration is a function of the presence of the bolus in the pharynx, size of the bolus, bolus consistency, breath cycle, ventilatory state and disease.

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