Pathophysiological mechanisms of resistive breathing

2021 ◽  
Vol 29 (2) ◽  
pp. 219-226
Author(s):  
Yury Yu. Byalovsky ◽  
Irina S. Rakitina
Keyword(s):  
Conditioned Reflex ◽  
External Respiration ◽  
Resistive Load ◽  
External Resistance ◽  
Conditioned Signal ◽  
Pathophysiological Mechanisms ◽  
Resistive Breathing ◽  
Resistive Loads ◽  
Reinforcement Value ◽  
Respiratory Reflex

AIM: This study aimed to explore the pathophysiological mechanisms of resistive breathing by using a model of a conditioned respiratory reflex to external resistance to breathing. MATERIALS AND METHODS: Inspiratory resistive loads were used 11, 28, 54, and 78 cmAq/l/s to model a conditioned respiratory reflex. External respiration was parametrized on the basis of the analysis of motor and ventilatory outputs. Conditioned signals were pure sounds exceeding the threshold of perception by 10 db at 2000 Hz frequency. All the test persons were divided into two groups (large and small groups) according to the initial reinforcement value. (1) In the large group (37 individuals), the conditioned reflex was formed from 11 cmAq/l/s that was subsequently increased stepwise in the load to 76 cmAq/l/s. (2) In the small group (18 individuals), the initial reinforcements were different gradations of resistive loads, with a stepwise transition to the other parameters of an unconditioned stimulus. The period of the isolated application of a conditioned signal (CS) was 20 s, the interval between signals was not fixed, varying from 2 min to 4 min. Six to eight combinations of the conditioned and unconditioned stimuli were used for 1 day of the experiment. RESULTS: The increase in the added respiratory resistance was associated with the pronounced reduction of pulmonary and alveolar ventilation, that is, with the hypoventilation type of resistive load realization. Changes in ventilation during the isolated application of a conditioned signal had an alternative character. In particular, as the reinforcement factor increased, a pronounced shift to hyperventilation was noted. CONCLUSION: The reinforcement value of the conditioned reflex changed stepwise, thereby significantly restructuring the proportion between the effectiveness of the adaptive activity in the realization of external resistance to inspiration (the time of stay under a certain load) and its physiological cost (totalities of the deviations of physiological and energy parameters).

CONDITIONED REFLEX MECHANISMS OF ADAPTATION TO ADDITIONAL BREATHING RESISTANCE

2021 ◽  
pp. 97-105
Author(s):  
Yu.Yu. Byalovskiy ◽  
I.S. Rakitina
Keyword(s):  
Conditioned Reflex ◽  
External Respiration ◽  
Respiratory Resistance ◽  
Conditioned Signal ◽  
Unconditioned Reflex ◽  
Breathing Resistance ◽  
Before And After ◽  
Resistive Loads ◽  
Aversive Behavior ◽  
Respiratory Reflex

The problem of adaptation to additional breathing resistance has recently become more urgent due to the growth of bronchopulmonary diseases. Therefore, there is a natural interest in non-drug strategies compensating resistive breathing in humans. The aim of the study was to assess conditioned reflex changes in the functional state of the subjects under additional breathing resistance. Materials and Methods. The work was carried out on 55 practically healthy subjects of both sexes, aged 18–36. Additional breathing resistance was modeled by inspiratory resistive loads of 40, 60, 70, and 80 % of the maximum intraoral pressure. The conditioned respiratory reflex to resistive respiratory load was developed as a short-delayed conditioned signal with a 30-second period of isolated action. The authors examined behavioral, vegetative, gas and energy indicators of the organism before and after the formation of a conditioned reflex. Results. It was observed that conditioned reflex shifts of physiological parameters in the process of adaptation to additional breathing resistance differ significantly from the corresponding unconditioned reflex changes both in nature and in intensity. Conditioned reflex mechanisms reduce the intensity of shifts in the motor component of the external respiration system, which, apparently, is the main reason to decrease the aversive behavior. Conclusion. Behavioral changes after the formation of a conditioned respiratory reflex to additional respiratory resistance are characterized by a decrease in aversive behavior patterns. The conditioned reflex realization of increasing resistive loads is expressed in a lower physiological cost of adaptation to additional respiratory resistance relative to the unconditioned reflex type of realization. Keywords: adaptation, conditioned respiratory reflex, additional breathing resistance. Проблема приспособления к дополнительному респираторному сопротивлению в последнее время становится все более актуальной в связи с ростом бронхолегочных заболеваний. Поэтому естественен интерес к нелекарственным механизмам компенсации резистивного дыхания человека. Целью исследования являлась оценка условно-рефлекторных изменений функционального состояния испытуемых в условиях дополнительного респираторного сопротивления. Материалы и методы. Работа проведена на 55 практически здоровых испытуемых обоего пола в возрасте от 18 до 36 лет. Дополнительное респираторное сопротивление моделировалось инспираторными резистивными нагрузками величиной 40, 60, 70 и 80 % от максимального внутриротового давления. Условный дыхательный рефлекс на резистивные дыхательные нагрузки вырабатывался по типу короткоотставленного с периодом изолированного действия условного сигнала 30 с. Исследовались поведенческие, вегетативные, газовые и энергетические показатели организма до и после формирования условного рефлекса. Результаты. Показано, что условно-рефлекторные сдвиги физиологических показателей в процессе приспособления к дополнительному респираторному сопротивлению существенно отличаются от соответствующих безусловно-рефлекторных изменений как по характеру, так и по интенсивности. Условно-рефлекторные механизмы уменьшают интенсивность сдвигов моторного компонента системы внешнего дыхания, что, по-видимому, является основной причиной снижения вероятности появления аверсивного поведения. Выводы. Поведенческие изменения после формирования условного дыхательного рефлекса на дополнительное респираторное сопротивление характеризуются снижением вероятности появления аверсивных форм поведения. Условно-рефлекторная реализация возрастающих по интенсивности резистивных нагрузок выражается в меньшей физиологической стоимости приспособления к дополнительному респираторному сопротивлению относительно безусловно-рефлекторного типа реализации. Ключевые слова: приспособление, условный дыхательный рефлекс, дополнительное респираторное сопротивление.

scholarly journals The influence of the initial reinforcement value on physiological parameters of conditioned respiratory reflex

2021 ◽  
Vol 9 (3) ◽  
pp. 377-386
Author(s):  
Yu.Yu. Byalovskiy ◽  
◽  
I.S. Rakitina ◽  
Keyword(s):  
Unconditioned Stimulus ◽  
Conditioned Reflex ◽  
Physiological Parameters ◽  
Resistive Load ◽  
Respiratory Resistance ◽  
Initial Value ◽  
Conditioned Reaction ◽  
Reinforcement Value ◽  
Respiratory Reflex

BACKGROUND: Most of the studies of the role of reinforcement in the formation of adaptive behavior were performed on animals. At the same time, such an experimental model as a conditioned respiratory reflex to resistive load, has not been sufficiently studied, although an unconditioned reflex to additional resistance to breathing, on the basis of which a conditioned one is formed, is a stable reaction that has clear quantitative evaluation criteria, and the conditioned reflex itself is relatively strong, easily normalized, reluctantly extinguished and does not require observance of a number of methodological conditions. AIM: To study the influence of the initial value of reinforcement on the physiological parameters of the conditioned respiratory reflex. MATERIALS AND METHODS: The work was carried out on people of both genders, 16 people, aged 18 to 44, practically healthy. The unconditioned stimulus was applied in four gradations of external respiratory resistance: 11; 28; 54; 76 cm water • l/sec. The conditioned reflex was formed by the classic type, the duration of application of the conditioned stimulus was not fixed and its end coincided with the end of the action of the unconditioned stimulus, the period of the isolated action of the conditioned signal was 10 sec. As physiological parameters, we studied the ventilatory and motor parameters of respiration, the temporal parameters of the conditioned reaction. RESULTS: The influence of the unconditioned stimulus on the value of the tidal volume after the combination in all subjects depended on the absolute reinforcement values used in this combination, and was weakly connected with the initial reinforcement value. The influence of the external resistance on breathing used in this combination was significantly higher on such parameters as intraoral pressure of inspiration and expiration; the role of the initial reinforcement value in the dynamics of the given parameters was not confirmed. CONCLUSIONS: Most “sensitive” to the action of the initial value of the resistive load were the temporal parameters of the conditioned respiratory reflex — the latent period and the time of the conditioned reaction; the parameters of the “ventilatory” and “motor” outputs of the external respiration system changed noticeably, the spirometric parameters showed very little dynamics, and the capnographic parameters practically did not change. The dynamics of the parameters of the conditioned respiratory reflex to increased external respiratory resistance permits to single out groups of signs that have the greatest semantic significance for evaluation of the system-forming and discriminating role of the initial gradation of the reinforcement factor.

IMPORTANCE OF MOTIVATION IN TOLERABILITY OF INCREASED BREATHING RESISTANCE

2019 ◽  
pp. 72-79
Author(s):  
Yu.Yu. Byalovskiy ◽  
I.S. Rakitina
Keyword(s):  
Functional State ◽  
Maximum Level ◽  
Technological Environment ◽  
Breathing Control ◽  
Aerodynamic Loads ◽  
Breathing Resistance ◽  
Resistive Breathing ◽  
Resistive Loads ◽  
Intraoral Pressure

Cortical mechanisms play an important role in breathing control under increased breathing resistance (resistive loads). Cortical mechanisms determine the level of voluntary motivation, which significantly affects the tolerance of resistive breathing loads. The purpose of the paper is to determine the effect of voluntary motivation on the tolerance of additional breathing resistance. Materials and Methods. The authors formed procedural motivation by means of moral encouragement or financial rewards of the subjects. Simulation of increased breathing resistance was performed using in-creasing values of thresholdless inspiratory aerodynamic loads: 40, 60, 70, and 80 % from the maximum intraoral pressure. Results. The maximum level of tolerance of additional breathing resistance was observed in volunteers with a material and subsidiary procedural motivation of activity. Under respiratory loads, these subjects demonstrated the greatest deviations of the functional state indicators. Undefined motivation based on the mobilization of goal-oriented resources with moral stimulation showed less efficiency. Lack of specially formed procedural motivation led to minimal tolerance of resistive loads. Conclusion. Procedural motivation, aimed at overcoming additional breathing resistance, significantly increases the tolerance of individual protective means of respiratory organs, which maintains health of workers in a polluted technological environment. Keywords: motivation, tolerance, increased breathing resistance. Большую роль в регуляции дыхания при увеличенном сопротивлении дыханию (резистивных нагрузках) играют кортикальные механизмы. Корковые механизмы определяют уровень произвольной мотивации, которая существенно влияет на переносимость резистивных дыхательных нагрузок. Цель исследования – определение влияния произвольной мотивации на переносимость дополнительного респираторного сопротивления. Материалы и методы. Процессуальную мотивацию формировали методом морального или материального поощрения испытуемых. Моделирование увеличенного сопротивления дыханию проводили с помощью предъявления возрастающих значений беспороговых инспираторных аэродинамических нагрузок: 40, 60, 70 и 80 % от максимального внутриротового давления. Результаты. Максимальный уровень переносимости дополнительного респираторного сопротивления наблюдался у добровольцев, у которых была сформирована материально-субсидивная процессуальная мотивация деятельности; у этой категории испытуемых во время действия дыхательных нагрузок отмечались наибольшие отклонения показателей функционального состояния. Произвольная мотивация на основе мобилизации волевых ресурсов при моральном стимулировании характеризовалась меньшей эффективностью, а отсутствие специально сформированной процессуальной мотивации сопровождалось минимальной переносимостью резистивных нагрузок. Выводы. Процессуальная мотивация, сформированная для преодоления дополнительного респираторного сопротивления, существенно повышает переносимость средств индивидуальной защиты органов дыхания, что имеет большое значение для сохранения здоровья работающих в условиях загрязненной производственной среды. Ключевые слова: мотивация, переносимость, увеличенное сопротивление дыханию.

Effects of expiratory loading on respiration in humans

1980 ◽  
Vol 49 (4) ◽  
pp. 601-608 ◽  
Author(s):  
B. Gothe ◽  
N. S. Cherniack
Keyword(s):  
Muscle Activity ◽  
Healthy Subjects ◽  
Respiratory Muscle ◽  
Resistive Load ◽  
Similar Magnitude ◽  
Occlusion Pressure ◽  
Ventilatory Responses ◽  
Residual Capacity ◽  
Resistive Loads ◽  
The Difference

We examined the effects of expiratory resistive loads of 10 and 18 cmH2O.l-1.s in healthy subjects on ventilation and occlusion pressure responses to CO2, respiratory muscle electromyogram, pattern of breathing, and thoracoabdominal movements. In addition, we compared ventilation and occlusion pressure responses to CO2 breathing elicited by breathing through an inspiratory resistive load of 10 cmH2O.l-1.s to those produced by an expiratory load of similar magnitude. Both inspiratory and expiratory loads decreased ventilatory responses to CO2 and increased the tidal volume achieved at any given level of ventilation. Depression of ventilatory responses to Co2 was greater with the larger than with the smaller expiratory load, but the decrease was in proportion to the difference in the severity of the loads. Occlusion pressure responses were increased significantly by the inspiratory resistive load but not by the smaller expiratory load. However, occlusion pressure responses to CO2 were significantly larger with the greater expiratory load than control. Increase in occlusion pressure observed could not be explained by changes in functional residual capacity or chemical drive. The larger expiratory load also produced significant increases in electrical activity measured during both inspiration and expiration. These results suggest that sufficiently severe impediments to breathing, even when they are exclusively expiratory, can enhance inspiratory muscle activity in conscious humans.

Inspiratory resistive load detection in conscious dogs

1991 ◽  
Vol 70 (3) ◽  
pp. 1284-1289 ◽  
Author(s):  
P. W. Davenport ◽  
D. J. Dalziel ◽  
B. Webb ◽  
J. R. Bellah ◽  
C. J. Vierck
Keyword(s):  
Training Stimulus ◽  
Detection Threshold ◽  
Resistive Load ◽  
Initial Training ◽  
Breathing Patterns ◽  
Physiological Mechanisms ◽  
Mechanical Loads ◽  
Load Detection ◽  
Resistive Loads ◽  
Tracheal Stoma

The physiological mechanisms mediating the detection of mechanical loads are unknown. This is, in part, due to the lack of an animal model of load detection that could be used to investigate specific sensory systems. We used American Foxhounds with tracheal stomata to behaviorally condition the detection of inspiratory occlusion and graded resistive loads. The resistive loads were presented with a loading manifold connected to the inspiratory port of a non-rebreathing valve. The dogs signaled detection of the load by lifting their front paw off a lever. Inspiratory occlusion was used as the initial training stimulus, and the dogs could reliably respond within the first or second inspiratory effort to 100% of the occlusion presentations after 13 trials. Graded resistances that spanned the 50% detection threshold were then presented. The detection threshold resistances (delta R50) were 0.96 and 1.70 cmH2O.l-1.s. Ratios of delta R50 to background resistance were 0.15 and 0.30. The near-threshold resistive loads did not significantly change expired PCO2 or breathing patterns. These results demonstrate that dogs can be conditioned to reliably and specifically signal the detection of graded inspiratory mechanical loads. Inspiration through the tracheal stoma excludes afferents in the upper extrathoracic trachea, larynx, pharynx, nasal passages, and mouth from mediating load detection in these dogs. It is unknown which remaining afferents (vagal or respiratory muscle) are responsible for load detection.

Relationship between resistive loads and P1 peak of respiratory-related evoked potential

1997 ◽  
Vol 83 (3) ◽  
pp. 918-926 ◽  
Author(s):  
Marie Knafelc ◽  
Paul W. Davenport
Keyword(s):  
Linear Relationship ◽  
Magnitude Estimation ◽  
Evoked Potential ◽  
Neural Activation ◽  
Resistive Load ◽  
Physical Magnitude ◽  
Series Of Experiments ◽  
Positive Peak ◽  
Resistive Loads ◽  
The Relationship

Knafelc, Marie, and Paul W. Davenport. Relationship between resistive loads and P1peak of respiratory-related evoked potential. J. Appl. Physiol. 83(3): 918–926, 1997.—This study investigated the relationship between resistive-load (ΔR) magnitude, the first positive peak (P1) amplitude of the respiratory-related evoked potential (RREP), and load-magnitude estimation (ME). The first experiments determined the subject’s ( n = 9) ME of five ΔR magnitudes randomly presented at the onset of an inspiration or by interrupting an inspiration. No significant differences were found in the slopes of the two different presentations, but the subjects estimated the interrupted inspiratory loads to be of lesser magnitude than loads presented at the onset of the breath. In the second series of experiments, the subject’s ( n = 6) RREPs were recorded in response to three ΔR magnitudes. The amplitude of the short-latency P1 peak of the RREP significantly increased with increases in the ΔR magnitude. A log-log plot of the group-averaged P1 amplitudes showed a linear relationship with ΔR. These results were consistent with the hypothesis that the perceptual magnitude of the respiratory load was related to the P1 amplitude of the RREP, suggesting the physical magnitude of the load-related stimulus was correlated with the amplitude of the cortical neural activation.

Thoracoabdominal asynchrony failed to grade airway obstructions in foals

2000 ◽  
Vol 88 (6) ◽  
pp. 2081-2087 ◽  
Author(s):  
Carrie Miller ◽  
Andrew M. Hoffman ◽  
Janice Hunter
Keyword(s):  
Phase Angle ◽  
Upper Airway ◽  
Clinical Feature ◽  
Resistive Load ◽  
Respiratory Inductive Plethysmography ◽  
Resistive Loading ◽  
Airway Obstructions ◽  
Airway Opening ◽  
Resistive Loads ◽  
Thoracoabdominal Asynchrony

Respiratory inductive plethysmography (RIP) can be used to obtain a valid measure of tidal volume in humans. This device also compares the contributions to ventilation of the thorax and abdomen. Although thoracoabdominal asynchrony is a prominent clinical feature for patients with airway obstruction, the accuracy of the RIP device to assess the severity of obstruction is unclear. This study analyzes how well RIP variables reflect the degree of a fixed external inspiratory plus expiratory resistive load in foals. Foals were employed because the species and age group are commonly afflicted with respiratory disease. Eight conscious, sedated (xylazine 1.25 mg/kg body wt) foals were subjected to randomly ordered resistive loads at the airway opening and, on a separate day, to histamine aerosol challenge. During resistive loading, phase angle changed significantly, as did phase relation ( P ≤ 0.05). However, no significant correlation was found between the degree of change in resistive load and the degree to which phase angle or relation was altered ( r s = 0.41 and 0.25, respectively). In addition, neither phase angle nor relation changed significantly with histamine challenge. We conclude that, although RIP variables changed markedly with fixed upper airway resistive loading, the degree to which they changed was erratic and therefore not useful for grading these obstructions. Furthermore, RIP variables were insensitive measures of histamine-induced bronchoconstriction.

Effect of ventilatory drive on the perceived magnitude of added loads to breathing

1982 ◽  
Vol 53 (4) ◽  
pp. 901-907 ◽  
Author(s):  
J. G. Burdon ◽  
K. J. Killian ◽  
E. J. Campbell
Keyword(s):  
Power Function ◽  
Muscle Force ◽  
Peak Inspiratory Pressure ◽  
Normal Subjects ◽  
Inspiratory Pressure ◽  
Resistive Load ◽  
Sensory Magnitude ◽  
Magnitude Scaling ◽  
Ventilatory Drive ◽  
Resistive Loads

Using open-magnitude scaling we studied the importance of ventilatory drive on the perceived magnitude of respiratory loads by applying a range of externally added resistances (2.1–77.1 cmH2O X l-1 X s) to normal subjects at rest and at three increasing levels of ventilatory drive induced by exercise, CO2-stimulated breathing, and hypoxia. Under all conditions studied the perceived magnitude of the added loads increased with the magnitude of the resistive load and as the underlying level of ventilatory drive increased. When the results were expressed in terms of peak inspiratory pressure, the perceived magnitude was related to the magnitude of the peak inspiratory pressure by a power function (mean r = 0.97). These results suggest that the perceived magnitude of added resistive loads increased with increasing ventilatory drive, in such a manner that the increase in sensory magnitude is proportional to the increase in the inspiratory muscle force developed and suggests that something dependent on this force mediates the sensation.

scholarly journals Repeatability of the Evaluation of Perception of Dyspnea in Normal Subjects Assessed Through Inspiratory Resistive Loads

2014 ◽  
Vol 8 (1) ◽  
pp. 41-47 ◽  
Author(s):  
Andréia K Fernandes ◽  
Bruna Ziegler ◽  
Glauco L Konzen ◽  
Paulo R.S Sanches ◽  
André F Müller ◽  
...  
Keyword(s):  
Normal Subjects ◽  
Cross Sectional Study ◽  
Resistive Load ◽  
Cross Sectional ◽  
Intra Class Correlation ◽  
Significant Difference ◽  
Loading System ◽  
Resistive Loads ◽  
The Brain ◽  
Intra Class Correlation Coefficient

Purpose: Study the repeatability of the evaluation of the perception of dyspnea using an inspiratory resistive loading system in healthy subjects. Methods: We designed a cross sectional study conducted in individuals aged 18 years and older. Perception of dyspnea was assessed using an inspiratory resistive load system. Dyspnea was assessed during ventilation at rest and at increasing resistive loads (0.6, 6.7, 15, 25, 46.7, 67, 78 and returning to 0.6 cm H2O/L/s). After breathing in at each level of resistive load for two minutes, the subject rated the dyspnea using the Borg scale. Subjects were tested twice (intervals from 2 to 7 days). Results: Testing included 16 Caucasian individuals (8 male and 8 female, mean age: 36 years). The median scores for dyspnea rating in the first test were 0 at resting ventilation and 0, 2, 3, 4, 5, 7, 7 and 1 point, respectively, with increasing loads. The median scores in the second test were 0 at resting and 0, 0, 2, 2, 3, 4, 4 and 0.5 points, respectively. The intra-class correlation coefficient was 0.57, 0.80, 0.74, 0.80, 0.83, 0.86, 0.91, and 0.92 for each resistive load, respectively. In a generalized linear model analysis, there was a statistically significant difference between the levels of resistive loads (p<0.001) and between tests (p=0.003). Dyspnea scores were significantly lower in the second test. Conclusion: The agreement between the two tests of the perception of dyspnea was only moderate and dyspnea scores were lower in the second test. These findings suggest a learning effect or an effect that could be at least partly attributed to desensitization of dyspnea sensation in the brain.

Effect of ethanol and naloxone on control of ventilation and load perception

1983 ◽  
Vol 55 (3) ◽  
pp. 929-934 ◽  
Author(s):  
T. M. Michiels ◽  
R. W. Light ◽  
C. K. Mahutte
Keyword(s):  
Normal Subjects ◽  
Ethanol Ingestion ◽  
Resistive Load ◽  
Load Compensation ◽  
Ventilatory Responses ◽  
Resistive Loading ◽  
Resistive Loads ◽  
Mouth Occlusion Pressure ◽  
Load Perception ◽  
Respiratory Depressant

The respiratory depressant effects of ethanol and their potential reversibility by naloxone were studied in 10 normal subjects. Ventilatory and mouth occlusion pressure (P0.1) responses to hypercapnia and hypoxia without and with an inspiratory resistive load (13 cmH2O X 1(-1) X S) were measured. The resistive load detected with 50% probability (delta R50) and the exponent (n) in Stevens' psychophysical law for magnitude estimation of resistive loads were studied using standard psychophysical techniques. Each of these studies was performed before ethanol ingestion, after ethanol ingestion (1.5 ml/kg, by mouth), and then again after naloxone (0.8 mg iv). Ethanol increased delta R50 (P less than 0.05) and decreased n (P less than 0.05). Naloxone caused no further change in these parameters. The load compensation (Lc), defined as the ratio of loaded to unloaded response slopes, was not significantly changed after ethanol and naloxone. No correlation was found between the Lc and delta R50 or n. The ventilatory and P0.1 responses to hypercapnia and hypoxia with and without inspiratory resistive loading decreased after ethanol (P less than 0.05, hypercapnia; NS, hypoxia). After naloxone the hypercapnic ventilatory responses increased (P less than 0.05). This suggests that the respiratory depressant effects of ethanol may be mediated via endorphins.

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