Genioglossus muscle responses to upper airway pressure changes: afferent pathways

1982 ◽  
Vol 52 (2) ◽  
pp. 445-450 ◽  
Author(s):  
O. P. Mathew ◽  
Y. K. Abu-Osba ◽  
B. T. Thach
Keyword(s):  
Airway Pressure ◽  
Upper Airway ◽  
Topical Anesthesia ◽  
Emg Activity ◽  
Afferent Pathway ◽  
Nerve Section ◽  
Primary Afferent ◽  
Genioglossus Muscle ◽  
Airway Reflex ◽  
Pressure Changes

The afferent pathway of an upper airway reflex in which genioglossus muscle electromyographic (GG EMG) activity is influenced by pharyngeal pressure changes was investigated in 20 anesthetized rabbits. We took advantage of the fact that the upper airway was separated into two compartments by pharyngeal closure occurring when the animals breathe through a tracheostomy. This allowed pressure to be delivered selectively either to the nose and nasopharynx or to the larynx and hypopharynx. Midcervical vagotomy did not eliminate the GG EMG response to pressure stimuli. On the other hand high cervical vagotomy or superior laryngeal nerve section eliminated the response in the laryngeal compartment, but not in the nasopharyngeal compartment. Topical anesthesia of the mucosa of the nose, pharynx, and larynx abolished the response in both compartments. Therefore we conclude that more than one afferent pathway exists for this upper airway pressure reflex; the primary afferent pathway from the laryngeal compartment is the superior laryngeal branch of the vagus nerve, whereas the primary afferent pathway for the nasopharynx is nonvagal. Trigeminal nerve, glossopharyngeal nerve, and/or nervus intermedius carry nonvagal afferents from the nasopharynx and nose. The topical anesthetic and nerve section studies suggest that superficial receptors mediate this response. The occurrence of swallowing in response to upper airway pressure changes and its elimination by topical anesthesia or superior mechanoreceptors may mediate both genioglossus respiratory responses and swallowing responses.

Influence of upper airway pressure changes on genioglossus muscle respiratory activity

1982 ◽  
Vol 52 (2) ◽  
pp. 438-444 ◽  
Author(s):  
O. P. Mathew ◽  
Y. K. Abu-Osba ◽  
B. T. Thach
Keyword(s):  
Airway Pressure ◽  
Upper Airway ◽  
Positive Pressure ◽  
Emg Activity ◽  
Airway Patency ◽  
Pharyngeal Airway ◽  
Reflex Pathways ◽  
Inspiratory Activity ◽  
Pressure Changes ◽  
Reflex System

The effects of change in pharyngeal airway pressure on electromyographic (EMG) activity of a pharyngeal dilating muscle (genioglossus) were investigated in 20 anesthetized rabbits. In vagotomized animals, upper airway loading maneuvers (nasal occlusion) increased the peak inspiratory activity of the genioglossus (GG) muscle on the first occluded breath. In contrast, “unloading” maneuvers (switching from nose to tracheostomy breathing) decreased GG activity. To further characterize the GG response, sustained pressure changes were produced within the isolated upper airway. Negative pressure increased GG activity; positive pressure decreased it. A poststimulus effect consisting of increased GG activity compared with control was seen following both negative- and positive-pressure stimuli. Cyclical pressure changes applied to the isolated upper airway increased the GG activity. These observations indicate the presence of reflex pathways that regulate GG muscle activity in response to upper airway pressure loads. This reflex system appears to play a role in regulating GG activity during tidal breathing and could be important in ensuring pharyngeal airway patency.

scholarly journals APNEA INDUCED BY UPPER AIRWAY PRESSURE CHANGES DECREASES WITH MATURATION IN PUPPIES

1984 ◽  
Vol 18 ◽  
pp. 397A-397A
Author(s):  
Oommen P Mathew ◽  
John T Fisher ◽  
Franca B Sant'Ambrogio ◽  
Giuseppe Sant'Ambrogio
Keyword(s):  
Airway Pressure ◽  
Upper Airway ◽  
Pressure Changes

Influence of upper airway pressure changes on respiratory frequency

1982 ◽  
Vol 49 (2) ◽  
pp. 223-233 ◽  
Author(s):  
Oommen P. Mathew ◽  
Yousef K. Abu-Osba ◽  
Bradley T. Thach
Keyword(s):  
Airway Pressure ◽  
Upper Airway ◽  
Respiratory Frequency ◽  
Pressure Changes

An Animal Model for Airway Sensory Deprivation Producing Obstructive Apnea with Postmortem Findings of Sudden Infant Death Syndrome

PEDIATRICS ◽  
1981 ◽  
Vol 68 (6) ◽  
pp. 796-801
Author(s):  
Yousef K. Abu-Osba ◽  
Oommen P. Mathew ◽  
Bradley T. Thach
Keyword(s):  
Sudden Infant Death Syndrome ◽  
Infant Death ◽  
Tracheostomy Tube ◽  
Upper Airway ◽  
Sudden Infant Death ◽  
Topical Anesthesia ◽  
Sudden Infant ◽  
Airway Patency ◽  
Pharyngeal Airway ◽  
Pressure Changes

A series of experiments was performed in rabbits to investigate the effects of airway sensory stimuli on upper airway patency. Pharyngeal airway closure was observed in rabbits breathing through a tracheostomy tube; pharyngeal patency was rapidly restored either by closing the tracheostomy tube, which forced the animals to resume nasal breathing, or by creating cyclical pressure changes in the nose and pharynx to stimulate respiratory tidal airflow. This airway opening effect of pressure fluctuations was eliminated by topical anesthesia of the airway mucosa, an observation suggesting that sensory stimulation from pressure change is needed for airway patency. The observation that dead animals have a patent pharyngeal airway that is resistant to collapse from negative intraluminal pressure, whereas animals breathing via a tracheostomy have a readily collapsible airway that is closed at zero transmural pressure, suggests that airway-constricting muscles close the airway when the animals breathe via the tracheostomy. Loss of electromyographic activity from airway-dilating muscles (genioglossus) was observed during tracheostomal breathing and was restored by cyclical pressure changes applied to the upper airway lumen, an observation further supporting the concept that airway reflexes responding to pressure regulate the activity of airway-dilating and airway-constricting muscles. Topical anesthesia of the upper airway mucous membrane, which eliminated these responses to pressure, was associated with an obstructed pharynegal airway and death from apparent asphyxia in either pentobarbital-anesthetized adult animals or young animals without general anesthetic. Death resulting from airway obstruction in this manner was associated with postmortem findings of sudden infant death syndrome (pulmonary edema and pleural petechiae) in the majority of animals.

Physiological Responses and Perceived Comfort to High Flow Nasal Cannula Therapy in Awake Adults: Effects of Flow Magnitude and Temperature

2021 ◽  
Author(s):  
Indra Narang ◽  
Jayne C. Carberry ◽  
Jane E. Butler ◽  
Simon C. Gandevia ◽  
Alan K.I. Chiang ◽  
...  
Keyword(s):  
Muscle Activity ◽  
Airway Pressure ◽  
Positive Airway Pressure ◽  
Upper Airway ◽  
High Flow ◽  
Nasal Cannula ◽  
Respiratory Support ◽  
High Flow Nasal Cannula ◽  
Genioglossus Muscle ◽  
Obstructive Sleep

Clinical use of heated, high flow nasal cannula (HFNC) for non-invasive respiratory support is increasing and may have a therapeutic role in stabilizing the upper airway in obstructive sleep apnea (OSA). However, physiological mechanisms by which HFNC therapy may improve upper-airway function and effects of different temperature modes are unclear. Accordingly, this study aimed to determine effects of incremental flows and temperature modes (heated and non-heated) of HFNC on upper airway muscle activity (genioglossus), pharyngeal airway pressure, breathing parameters and perceived comfort. Six participants (2 females, aged 35±14 years) were studied during wakefulness in supine position and received HFNC at variable flows (0-60 L/min) during heated (37ºC) and non-heated (21ºC) modes. Breathing parameters via calibrated Respitrace inductance bands (chest and abdomen), upper-airway pressures via airway transducers, and genioglossus muscle activity via intra-muscular bipolar fine wire electrodes were measured. Comfort levels during HFNC were quantified using a visual analogue scale. Increasing HFNC flows did not increase genioglossus muscle activation despite increased negative epiglottic pressure swings (p=0.009). HFNC provided ~7cmH2O positive airway pressure at 60 L/min in non-heated and heated modes. In addition, increasing the magnitude of HFNC flow reduced breathing frequency (p=0.045), increased expiratory time (p=0.040), increased peak inspiratory flow (p=0.002), and increased discomfort (p=0.004). Greater discomfort occurred at higher flows in non-heated versus heated mode (p=0.034). These findings provide novel insight into key physiological changes that occur with HFNC for respiratory support and indicate the primary mechanism for improved upper-airway stability is positive airway pressure, not increased pharyngeal muscle activity.

Upper airway dilating forces during wakefulness and sleep in dogs

1986 ◽  
Vol 61 (6) ◽  
pp. 2148-2155 ◽  
Author(s):  
A. S. Goh ◽  
F. G. Issa ◽  
C. E. Sullivan
Keyword(s):  
Rem Sleep ◽  
Airway Pressure ◽  
Slow Wave Sleep ◽  
Upper Airway ◽  
Base Line ◽  
Phasic Change ◽  
Isolated Segment ◽  
The Mean ◽  
Line Level ◽  
Pressure Changes

We measured the pressure within an isolated segment of the upper airway in three dogs during wakefulness (W), slow-wave sleep (SWS) and rapid-eye-movement (REM) sleep. Measurements were taken from a segment of the upper airway between the nares and midtrachea while the dog breathed through a tracheostoma. These pressure changes represented the sum of respiratory-related forces generated by all muscles of the upper airway. The mean base-line level of upper airway pressure (Pua) was -0.5 +/- 0.03 cmH2O during W, increased by a mean of 2.1 +/- 0.2 cmH2O during SWS, and was variable during REM sleep. The mean inspiratory-related phasic change in Pua was -1.2 +/- 0.1 cmH2O during wakefulness. During SWS, this phasic change in Pua decreased significantly to a mean of -0.9 +/- 0.1 cmH2O (P less than 0.05). During REM sleep, the phasic activity was extremely variable with periods in which there were no fluctuations in Pua and others with high swings in Pua. These data indicate that in dogs the sum of forces which dilate the upper airway during W decreases during SWS and REM sleep. The consistent coupling between inspiratory drive and upper airway dilatation during wakefulness persists in SWS, but is frequently uncoupled during REM sleep.

Soft palate muscle responses to negative upper airway pressure

1999 ◽  
Vol 86 (2) ◽  
pp. 523-530 ◽  
Author(s):  
T. C. Amis ◽  
N. O’Neill ◽  
J. R. Wheatley ◽  
T. van der Touw ◽  
E. di Somma ◽  
...  
Keyword(s):  
Soft Palate ◽  
Muscle Activity ◽  
Airway Pressure ◽  
Upper Airway ◽  
Emg Activity ◽  
Afferent Activity ◽  
Afferent Pathways ◽  
Levator Veli Palatini ◽  
Anesthetized Dogs ◽  
Muscle Responses

The afferent pathways and upper airway receptor locations involved in negative upper airway pressure (NUAP) augmentation of soft palate muscle activity have not been defined. We studied the electromyographic (EMG) response to NUAP for the palatinus, tensor veli palatini, and levator veli palatini muscles in 11 adult, supine, tracheostomized, anesthetized dogs. NUAP was applied to the nasal or laryngeal end of the isolated upper airway in six dogs and to four to six serial upper airway sites from the nasal cavity to the subglottis in five dogs. When NUAP was applied at the larynx, peak inspiratory EMG activity for the palatinus and tensor increased significantly ( P< 0.05) and plateaued at a NUAP of −10 cmH2O. Laryngeal NUAP failed to increase levator activity consistently. Nasal NUAP did not increase EMG activity for any muscle. Consistent NUAP reflex recruitment of soft palate muscle activity only occurred when the larynx was exposed to the stimulus and, furthermore, was abolished by bilateral section of the internal branches of the superior laryngeal nerves. We conclude that soft palate muscle activity may be selectively modulated by afferent activity originating in the laryngeal and hypopharyngeal airway.

scholarly journals Upper airway pressure-flow relationships and pharyngeal constrictor EMG activity during prolonged expiration in awake goats

2008 ◽  
Vol 105 (1) ◽  
pp. 100-108
Author(s):  
K. D. O'Halloran ◽  
G. E. Bisgard
Keyword(s):  
Airway Pressure ◽  
Muscle Activation ◽  
Upper Airway ◽  
Systemic Administration ◽  
Emg Activity ◽  
Airway Closure ◽  
Pressure Flow ◽  
Airway Occlusion ◽  
Adductor Muscles ◽  
Tracheal Pressure

We undertook the present investigation to establish whether narrowing/closure of the upper airway occurs during spontaneous and provoked respiratory rhythm disturbances and whether pharyngeal constrictor muscle recruitment occurs coincident with upper airway occlusion during prolonged expiratory periods. Upper airway pressure-flow relationships and middle pharyngeal constrictor (mPC) EMG activities were recorded in 11 adult female goats during spontaneous and provoked prolongations in expiratory time (Te). A total of 213 spontaneous prolongations of expiration were recorded. Additionally, 169 prolonged expiratory events preceded by an augmented breath were included in the analyses. In separate trials on different days, Te was prolonged by systemic administration of dopamine, by raising the inspired fraction of O2 from 0.10 to 1.00 during poikilocapnic conditions or by systemic administration of clonidine. Continuous tonic activation of the mPC EMG was observed during each prolonged Te period regardless of the duration or initiating cause. However, significant increases in subglottic tracheal pressure, with expiratory airflow braking indicative of upper airway narrowing or closure, was only observed during spontaneous events without a preceding augmented breath and during clonidine-induced events. Tonic mPC activation proved an unreliable indicator of airway occlusion. Furthermore, mPC muscle activation alone is not sufficient to induce pharyngeal occlusion during prolonged expiration. Our data suggest that airway closure is not a common occurrence during provoked respiratory disturbances in awake goats. We propose that airway closure, when present during prolonged Te, is more likely dependent on activation of laryngeal adductor muscles with glottic braking independent of pharyngeal narrowing.

Mechanisms contributing to the response of upper-airway muscles to changes in airway pressure

2015 ◽  
Vol 118 (10) ◽  
pp. 1221-1228 ◽  
Author(s):  
Jayne C. Carberry ◽  
Hanna Hensen ◽  
Lauren P. Fisher ◽  
Julian P. Saboisky ◽  
Jane E. Butler ◽  
...  
Keyword(s):  
Negative Pressure ◽  
Airway Pressure ◽  
Upper Airway ◽  
Nasal Breathing ◽  
Quiet Breathing ◽  
Surface Receptors ◽  
Reflex Responses ◽  
Airway Collapsibility ◽  
Upper Airway Collapsibility ◽  
Pressure Changes

This study assessed the effects of inhaled lignocaine to reduce upper airway surface mechanoreceptor activity on 1) basal genioglossus and tensor palatini EMG, 2) genioglossus reflex responses to large pulses (∼10 cmH2O) of negative airway pressure, and 3) upper airway collapsibility in 15 awake individuals. Genioglossus and tensor palatini muscle EMG and airway pressures were recorded during quiet nasal breathing and during brief pulses (250 ms) of negative upper-airway pressure. Lignocaine reduced peak inspiratory (5.6 ± 1.5 vs. 3.8 ± 1.1% maximum; mean ± SE, P < 0.01) and tonic (2.8 ± 0.8 vs. 2.1 ± 0.7% maximum; P < 0.05) genioglossus EMG during quiet breathing but had no effect on tensor palatini EMG (5.0 ± 0.8 vs. 5.0 ± 0.5% maximum; P = 0.97). Genioglossus reflex excitation to negative pressure pulses decreased after anesthesia (60.9 ± 20.7 vs. 23.6 ± 5.2 μV; P < 0.05), but not when expressed as a percentage of the immediate prestimulus baseline. Reflex excitation was closely related to the change in baseline EMG following lignocaine ( r2 = 0.98). A short-latency genioglossus reflex to rapid increases from negative to atmospheric pressure was also observed. The upper airway collapsibility index (%difference) between nadir choanal and epiglottic pressure increased after lignocaine (17.8 ± 3.7 vs. 28.8 ± 7.5%; P < 0.05). These findings indicate that surface receptors modulate genioglossus but not tensor palatini activity during quiet breathing. However, removal of input from surface mechanoreceptors has minimal effect on genioglossus reflex responses to large (∼10 cmH2O), sudden changes in airway pressure. Changes in pressure rather than negative pressure per se can elicit genioglossus reflex responses. These findings challenge previous views and have important implications for upper airway muscle control.

Dilating forces on the upper airway of anesthetized dogs

1985 ◽  
Vol 58 (2) ◽  
pp. 452-458 ◽  
Author(s):  
K. P. Strohl ◽  
J. M. Fouke
Keyword(s):  
Muscle Activation ◽  
Moving Average ◽  
Upper Airway ◽  
Pressure Change ◽  
Emg Activity ◽  
Lung Inflation ◽  
Anesthetized Dogs ◽  
Cervical Trachea ◽  
Pressure Changes ◽  
Spontaneously Breathing

We reasoned that in an isolated sealed upper airway a pressure change would be caused by a change in airway volume. In eight spontaneously breathing anesthetized dogs, we isolated the upper airway by transecting the cervical trachea and sealing it from the lung and from the atmosphere. Pressure changes in this isolated upper airway were studied in relation to respiratory phase as evidenced by alae nasi electromyographic (EMG) activation and tidal volume measured at the distal trachea. A fall in pressure, indicating airway dilation, occurred with each spontaneous respiratory effort. Like the moving average of the alae nasi EMG, the pressure drop reached a peak value early in inspiration, was inhibited by further lung inflation, and was absent during passive mechanical ventilation. End-expiratory tracheal occlusion or vagotomy prolonged and augmented EMG activity and also the inspiratory fall in upper airway pressure. Increased levels of CO2 increased the magnitude of change in pressure during inspiration. An inhibiting effect of lung inflation was present to an equal extent at low and high levels of chemical drive. We show that dilation of the airway is concurrent with upper airway muscle activation during early inspiration, that this dilation increases with increasing chemical drive, and that vagal reflexes during lung inflation inhibit this dilation during the latter half of inspiration.

Sign in / Sign up

Export Citation Format

Share Document