Coordination of swallowing and respiration in unconscious subjects

1991 ◽  
Vol 70 (3) ◽  
pp. 988-993 ◽  
Author(s):  
T. Nishino ◽  
K. Hiraga
Keyword(s):  
General Anesthesia ◽  
Tidal Volume ◽  
Endotracheal Tube ◽  
Breathing Pattern ◽  
Recovery Period ◽  
Respiratory Frequency ◽  
Breathing Patterns ◽  
Expiratory Phase ◽  
Unconscious Patients

We investigated the coordination of swallowing and breathing in 11 unconscious patients with an endotracheal tube in place during the recovery period from general anesthesia. Swallows occurred during both the inspiratory and expiratory phases with no preponderant occurrence during either phase. When a swallow occurred during inspiration, the inspiration was interrupted immediately and was followed by expiration, but the durations of both inspiration and expiration were progressively increased as the time from the onset of inspiration to the onset of swallowing was progressively delayed. A swallow coinciding with the expiratory phase progressively prolonged the duration of the expiration that had been interrupted as the timing of swallowing was progressively delayed. Repeated swallows invariably and in a predictable manner caused changes in the breathing pattern. Thus when the frequency of regularly repeated swallows was relatively high, the breathing pattern was characterized by regular, shallow, and rapid breaths. When the frequency of regularly repeated swallows was relatively low, the breathing pattern was characterized by regular, deep, and slow breaths. When the frequency of repeated swallows was irregular, the breathing patterns were characterized by inconsistent changes in tidal volume and respiratory frequency. Our results indicate that, in unconscious subjects, some mechanisms integrating respiration and swallowing are operative and responsible for changes in breathing patterns during swallowing.

Normoxic and hypoxic breathing pattern in newborn grey seals

1989 ◽  
Vol 67 (2) ◽  
pp. 483-487 ◽  
Author(s):  
Jacopo P. Mortola ◽  
Clement Lanthier
Keyword(s):  
Tidal Volume ◽  
Breathing Pattern ◽  
Halichoerus Grypus ◽  
Breathing Rate ◽  
Allometric Relationships ◽  
Breathing Patterns ◽  
Hypoxic Conditions ◽  
Regulation Of Breathing ◽  
Expiratory Flow

We studied the breathing patterns of three newborn grey seals (Halichoerus grypus) at 2 – 3 days of age under normoxic and hypoxic conditions with the barometric technique, which does not require the animal to be restrained. Normoxic tidal volume was deeper and breathing rate slower than expected for newborns of this size on the basis of previously published allometric relationships. In addition, two characteristics were readily apparent: (i) occasional sudden long apneas, often exceeding 30 s in duration, and (ii) consistent brief interruptions of expiratory flow. Neither aspect is common in terrestrial newborns of this age, but both have been previously observed in adult seals. During hypoxia (10 min of 15% O2 and 10 min of 10% O2), ventilation increased markedly and steadily, at variance with what occurs in newborns of other species, indicating a precocial development of the regulation of breathing. This latter result also suggests that the blunted response to hypoxia previously reported in adult seals may be acquired postnatally with diving experience.

scholarly journals Impact of cervical spinal cord contusion on the breathing pattern across the sleep-wake cycle in the rat

2019 ◽  
Vol 126 (1) ◽  
pp. 111-123 ◽  
Author(s):  
Kun-Ze Lee
Keyword(s):  
Spinal Cord ◽  
Tidal Volume ◽  
Spinal Injury ◽  
Cervical Spinal Cord ◽  
Minute Ventilation ◽  
Respiratory Frequency ◽  
Breathing Patterns ◽  
Cord Injury ◽  
Spinal Contusion ◽  
Cervical Spinal Injury

The present study was designed to investigate breathing patterns across the sleep-wake state following a high cervical spinal injury in rats. The breathing patterns (e.g., respiratory frequency, tidal volume, and minute ventilation), neck electromyogram, and electroencephalography of unanesthetized adult male rats were measured at the acute (i.e., 1 day), subchronic (i.e., 2 wk), and/or chronic (i.e., 6 wk) injured stages after unilateral contusion of the second cervical spinal cord. Cervical spinal cord injury caused a long-term reduction in the tidal volume but did not influence the sleep-wake cycle duration. The minute ventilation during sleep was usually lower than that during the wake period in uninjured animals due to a decrease in respiratory frequency. However, this sleep-induced reduction in respiratory frequency was not observed in contused animals at the acute injured stage. By contrast, the tidal volume was significantly lower during sleep in contused animals but not uninjured animals from the acute to the chronic injured stage. Moreover, the frequency of sigh and postsigh apnea was elevated in acutely contused animals. These results indicated that high cervical spinal contusion is associated with exacerbated sleep-induced attenuation of the tidal volume and higher occurrence of sleep apnea, which may be detrimental to respiratory functional recovery after cervical spinal cord injury. NEW & NOTEWORTHY Cervical spinal injury is usually associated with sleep-disordered breathing. The present study investigated breathing patterns across sleep-wake state following cervical spinal injury in the rat. Unilateral cervical spinal contusion significantly impacted sleep-induced alteration of breathing patterns, showing a blunted frequency response and exacerbated attenuated tidal volume and occurrence of sleep apnea. The result enables us to investigate effects of cervical spinal injury on the pathogenesis of sleep-disordered breathing and evaluate potential therapies to improve respiration.

Effect of respiratory apparatus on respiration

1984 ◽  
Vol 57 (2) ◽  
pp. 475-480 ◽  
Author(s):  
C. Weissman ◽  
J. Askanazi ◽  
J. Milic-Emili ◽  
J. M. Kinney
Keyword(s):  
Tidal Volume ◽  
Duty Cycle ◽  
Breathing Pattern ◽  
Minute Ventilation ◽  
Inspiratory Flow ◽  
Percentage Increase ◽  
Breathing Patterns ◽  
Normal Volunteers ◽  
Abdominal Operation ◽  
Respiratory Apparatus

A mouthpiece plus noseclip (MP & NC) is frequently used in performing measurements of breathing patterns. Although the effects the apparatus exerts on breathing patterns have been studied, the mechanism of the changes it causes remains unclear. The current study examines the effects on respiratory patterns of a standard (17-mm-diam) MP & NC during room air (RA) breathing and the administration of 2 and 4% CO2 in normal volunteers and in patients 2–4 days after abdominal operation. When compared with values obtained with a noninvasive canopy system, the MP & NC induced increases in minute ventilation (VE), tidal volume (VT), and mean inspiratory flow (VT/TI), but not frequency (f) or inspiratory duty cycle, during both RA and CO2 administration. The percentage increase in VE, VT, and VT/TI caused by the MP & NC decreased as the concentration of CO2 increased. During RA breathing, the application of noseclip alone resulted in a decrease in f and an increase in VT, but VE and VT/TI were unchanged. The changes were attenuated during the administration of 2 and 4% CO2. Reducing the diameter of the mouthpiece to 9 mm abolished the alterations in breathing pattern observed with the larger (17-mm) diameter MP.

Relationship between Cr and breathing pattern in mechanically ventilated patients

1994 ◽  
Vol 77 (6) ◽  
pp. 2703-2708 ◽  
Author(s):  
H. Burnet ◽  
M. Bascou-Bussac ◽  
C. Martin ◽  
Y. Jammes
Keyword(s):  
Linear Regression ◽  
Tidal Volume ◽  
Multiple Linear Regression ◽  
Breathing Pattern ◽  
Minute Ventilation ◽  
Respiratory Frequency ◽  
Upper Airways ◽  
Mechanically Ventilated ◽  
Mechanically Ventilated Patients ◽  
Ventilated Patients

In mechanically ventilated patients the natural gas-conditioning process of the upper airways is bypassed by the use of an endotracheal tube or a tracheostomy. We hypothesized that under these conditions the breathing pattern may greatly influence the convective respiratory heat loss (Cr). Cr values were computed from minute ventilation (VE) and inspiratory and expiratory gas temperatures, which were measured in six patients under mechanical ventilation for the management of cranial trauma. In each patient the effects of 11–20 different breathing patterns were investigated. Relationships between Cr and VE and between combined tidal volume and respiratory frequency were obtained by simple and multiple linear regression methods, respectively. Comparison of the standard errors of estimate indicated that multiple linear regression gives the best fit. Thus, Cr was highly dependent on the breathing pattern and was not related only to VE. For the same VE value, Cr was higher when VE was achieved with high tidal volume and low respiratory frequency. These data are consistent with previous studies in which thermal exchanges through the upper airways were taxed by hyperventilation of frigid air.

Breathing pattern of kittens during hypoxia

1984 ◽  
Vol 56 (1) ◽  
pp. 12-17 ◽  
Author(s):  
C. E. Blanco ◽  
M. A. Hanson ◽  
P. Johnson ◽  
H. Rigatto
Keyword(s):  
Arterial Pressure ◽  
Tidal Volume ◽  
Breathing Pattern ◽  
Esophageal Pressure ◽  
Central Mechanism ◽  
Respiratory Frequency ◽  
Low Frequencies ◽  
Pentobarbital Sodium

In 19 pentobarbital sodium-anesthetized kittens aged 5–34 days, inspired O2 was reduced from 21 to 6–512%. Respiratory frequency (f) and tidal volume (VT) increased within 30 s. Over 5 min f fell to about 60% below control; VT usually fell but remained above control. Arterial pressure fell in 80% of trials, sometimes before f fell. Arterial CO2 was below control, but raising inspired CO2 to keep expired CO2 at control did not prevent the fall in f and VT. The relation between VT and esophageal pressure or diaphragm electromyogram (EMG) did not change consistently, nor was the ratio of high to low frequencies in the diaphragm EMG altered. Carotid chemoreceptor discharge increased within 15 s, and at 5 min it was much above control. We conclude that the change in the breathing pattern in hypoxia is probably due to the activation of a central mechanism.

Restraining hamsters alters their breathing pattern

1991 ◽  
Vol 70 (3) ◽  
pp. 1271-1276 ◽  
Author(s):  
T. D. Sweeney ◽  
D. E. Leith ◽  
J. D. Brain
Keyword(s):  
Muscle Strength ◽  
Exercise Training ◽  
Tidal Volume ◽  
Adult Male ◽  
Breathing Pattern ◽  
Minute Volume ◽  
Respiratory Frequency ◽  
Prior Exercise ◽  
Sedentary Group ◽  
Inhaled Aerosols

Does the restraint required for head or nose-only exposure of rodents to inhaled aerosols or gases alter their breathing pattern? And does prior exercise training, which may increase muscle strength, affect this response to restraint? To answer those questions, we measured breathing pattern in 11 adult male hamsters while they were either 1) free to move in small cages or 2) closely restrained in head-out cones. The measurements were repeated after hamsters spent 6 wk either sedentary in standard cages or in cages with exercise wheels. Hamsters were placed in a plethysmograph to measure respiratory frequency (f) and tidal volume (VT). Their product is minute volume (V). When restrained, f and V were 1.9 and 1.7 times, respectively, greater than when hamsters were free, but VT did not change. After 6 wk, the sedentary group responded differently to restraint; f increased 3-fold, VT decreased by one-half, and V increased 1.6-fold. Exercised hamsters increased f 2.3-fold and decreased VT by one-third; V increased by 1.5-fold. In inhalation studies, changes in breathing pattern would significantly influence the amount of material inhaled, the fraction retained, and thus the amount and distribution of material deposited in the lungs.

Breathing pattern of anesthetized humans during pancuronium-induced partial paralysis

1988 ◽  
Vol 64 (1) ◽  
pp. 78-83 ◽  
Author(s):  
T. Nishino ◽  
N. Yokokawa ◽  
K. Hiraga ◽  
Y. Honda ◽  
T. Mizuguchi
Keyword(s):  
Tidal Volume ◽  
Respiratory Muscles ◽  
Respiratory Frequency ◽  
Breathing Patterns ◽  
Inspiratory Time ◽  
Muscle Paralysis ◽  
Airway Occlusion ◽  
Enflurane Anesthesia ◽  
Before And After ◽  
The Face

We investigated the breathing patterns of 17 subjects anesthetized with enflurane before and after partial muscle paralysis produced by pancuronium bromide. In the face of significant muscle weakness produced by pancuronium, breathing patterns are characterized by decreases in both tidal volume and respiratory frequency. The decreased tidal volume corresponded to the decrease in occlusion pressure, indicating that the decreased tidal volume results solely from a decreased contractile force of the respiratory muscles. The decreased respiratory frequency was due to prolongation of both inspiratory and expiratory time without changing the ratio of the inspiratory time to the total breath time. Withdrawal of phasic vagal influence by airway occlusion before partial muscle paralysis revealed that an active Breuer-Hering inflation reflex was operative in only 8 of all 17 subjects. Since the contribution of the Breuer-Hering inflation reflex alone does not seem to account for the consistent decrease in respiratory frequency, some other mechanisms modulating respiratory frequency might be involved in the characteristic breathing patterns during partial muscle paralysis under enflurane anesthesia.

scholarly journals The Interrelationship Between Pulmonary Mechanics and the Spontaneous Breathing Pattern in the Tokay Lizard, Gekko Gecko

1984 ◽  
Vol 113 (1) ◽  
pp. 203-214 ◽  
Author(s):  
WILLIAM K. MILSOM
Keyword(s):  
Tidal Volume ◽  
Spontaneous Breathing ◽  
Breathing Pattern ◽  
Pulmonary Ventilation ◽  
Periodic Breathing ◽  
Breath Holding ◽  
Pulmonary Mechanics ◽  
Respiratory Drive ◽  
Breathing Patterns ◽  
Gekko Gecko

The normal breathing pattern of the Tokay gecko (Gekko gecko) consists of single breaths or bursts of a few breaths separated by periods of breath holding. Increases in pulmonary ventilation that accompany rises in body temperature are caused by increases in respiratory frequency due to shortening of the periods of breath holding. Tidal volume and breath duration remain relatively constant. Measurements of the mechanical work associated with spontaneous breathing yielded values that were similar to those calculated for breaths of the same size and duration based on work curves generated during pump ventilation of anaesthetized animals. In this species, the pattern of periodic breathing and the ventilatory responses to changes in respiratory drive correspond with predictions of optimal breathing patterns based on calculations of the mechanical cost of ventilation. Bilateral vagotomy drastically alters the breathing pattern producing an elevation in tidal volume, a slowing of breathing frequency, and a prolongation of the breath duration. These alterations greatly increase the mechanical cost of ventilation. These data suggest that periodic breathing in this species may represent an adaptive strategy which is under vagal afferent control and which serves to minimize the cost of breathing.

scholarly journals Central histamine contributed to temperature-induced polypnea in mice

2000 ◽  
Vol 89 (2) ◽  
pp. 770-776 ◽  
Author(s):  
Masahiko Izumizaki ◽  
Michiko Iwase ◽  
Hiroshi Kimura ◽  
Takayuki Kuriyama ◽  
Ikuo Homma
Keyword(s):  
Body Temperature ◽  
Breathing Pattern ◽  
Histidine Decarboxylase ◽  
Specific Inhibitor ◽  
Respiratory Frequency ◽  
The Other ◽  
Body Temperatures ◽  
Breathing Patterns ◽  
Expiratory Time ◽  
Behavioral Studies

Breathing pattern is influenced by body temperature. However, the central mechanism for changing breathing patterns is unknown. Central histamine is involved in heat loss mechanisms in behavioral studies, but little is known about its effect on breathing patterns. We examined first the effect of body temperature on breathing patterns with increasing hypercapnia in conscious mice and then that of the depletion of central histamine by S(+)-α-fluoromethylhistidine hydrochloride (α-FMH) (100 mg/kg ip), a specific inhibitor of histidine decarboxylase, at normal and raised body temperatures. A raised body temperature increased respiratory frequency with reductions in both inspiratory and expiratory time and decreased tidal volume. On the other hand, α-FMH lowered respiratory frequency with a prolongation of expiratory time at the raised temperature; however, this was not observed at a normal temperature. These results indicate that central histamine contributes to an increase in respiratory frequency as a result of a reduction in expiratory time when body temperature is raised.

Human breathing patterns on mouthpiece or face mask during air, CO2, or low O2

1982 ◽  
Vol 53 (5) ◽  
pp. 1281-1290 ◽  
Author(s):  
J. A. Hirsch ◽  
B. Bishop
Keyword(s):  
Steady State ◽  
Tidal Volume ◽  
Elevated Co2 ◽  
Breathing Pattern ◽  
Face Mask ◽  
Simple Consequence ◽  
Breathing Patterns ◽  
Oral Breathing ◽  
Ventilatory Responses ◽  
Breathing Apparatus

Steady-state breathing patterns on mouthpiece and noseclip (MP) and face mask (MASK) during air and chemostimulated breathing were obtained from pneumotachometer flow. On air, all 10 subjects decreased frequency (f) and increased tidal volume (VT) on MP relative to that on MASK without changing ventilation (VE), mean inspiratory flow (VT/TI), or mean expiratory flow (VT/TE). On elevated CO2 and low O2, MP exaggerated the increase in VE, f, and VT/TE due to profoundly shortened TE. On elevated CO2, MASK exaggerated VT increase with little change in f. Increased VE and VT/TI were thus due to increased VT. During low O2 on MASK, both VT and f increased. During isocapnia, shortened TE accounted for increased f; during hypocapnia, increased f was related primarily to shortened TI. Thus the choice of a mouthpiece or face mask differentially alters breathing pattern on air and all components of ventilatory responses to chemostimuli. In addition, breathing apparatus effects are not a simple consequence of a shift from oronasal to oral breathing, since a noseclip under the mask did not change breathing pattern from that on mask alone.

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