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Journal of Voice : Official Journal of... Mar 2021Previous investigations have reported that a chronic cough that is refractory to medical therapies improves with behavioral therapies. However, the treatment parameters...
OBJECTIVE
Previous investigations have reported that a chronic cough that is refractory to medical therapies improves with behavioral therapies. However, the treatment parameters that may account for improvement in cough symptoms have not yet been objectively documented. The purpose of this study was to document changes in chronic refractory cough using a breath training protocol.
METHODS
The charts of 27 patients with a long-term chronic cough (>6 months) refractory to various medical treatments were reviewed. These patients received 2-4 sessions of breath training therapy over a 6-month period. Treatment sessions consisted of breathing modification exercises such as those reported in the literature. Aerodynamic parameters including mean estimated subglottal air pressure, mean airflow rate, laryngeal airway resistance, and maximum phonation time were obtained before treatment and 6 months after therapy. Patients also completed the Cough Severity Index at the first visit and 6 months after treatment.
RESULTS
Twenty four of the 27 patients (M:F = 6:21), with a mean age of 62.4 (range = 28-78, median = 66) had significant Cough Severity Index improvement from 16.74 to 10.04 (P< 0.001) after therapy. Maximum phonation time increased significantly from 12.00 to 16.38 seconds (P= 0.006); mean estimated subglottic air pressure decreased significantly from 7.58 to 6.36 cm HO (P= 0.004); laryngeal airway resistance decreased significantly from 52.97 to 40.64 ppm (P= 0.013).
CONCLUSION
This investigation provides evidence that patients who followed a protocol that focused on a breath training program reduced their chronic cough. Significant relationships between patient self-assessment of chronic cough and aerodynamic measures of subglottic pressure and glottal airway resistance were found in this group.
Topics: Airway Resistance; Cough; Glottis; Humans; Larynx; Phonation; Respiration
PubMed: 31585835
DOI: 10.1016/j.jvoice.2019.08.026 -
Facial Plastic Surgery : FPS Jun 2024Several methods are available for evaluating nasal breathing and nasal airflow, as this evaluation may be made from several different perspectives.Physiologic methods... (Review)
Review
Several methods are available for evaluating nasal breathing and nasal airflow, as this evaluation may be made from several different perspectives.Physiologic methods for nasal airway evaluation directly measure nasal airflow or nasal airway resistance, while anatomical methods measure nasal airway dimensions. Subjective methods evaluate nasal breathing through several validated patient-reported scales assessing nasal breathing. Computational fluid dynamics evaluates nasal airflow through the analysis of several physics' variables of the nasal airway.Being familiar to these methods is of utmost importance for the nasal surgeon to be able to understand data provided by the different methods and to be able to choose the combination of evaluation methods that will provide the information most relevant to each clinical situation.
Topics: Humans; Respiration; Nasal Cavity; Airway Resistance; Nasal Obstruction; Rhinomanometry; Nose; Hydrodynamics
PubMed: 38331036
DOI: 10.1055/s-0044-1779043 -
Critical Reviews in Biomedical... 2015Spirometry is one of the most widely used tests in the assessment and monitoring of asthma. However, spirometry cannot be performed in very young children and some adult... (Review)
Review
Spirometry is one of the most widely used tests in the assessment and monitoring of asthma. However, spirometry cannot be performed in very young children and some adult patients, and is poorly sensitive to small airways, which are primarily involved in the pathophysiology of asthma. The forced oscillation technique (FOT) has emerged as a powerful alternative technique that instead characterizes respiratory mechanics during normal breathing with no forced maneuver. In this review we highlight the current state of the art of the FOT and its utility in the assessment of lung function in asthma. First we briefly discuss the clinical features and characteristics of asthma. This is followed by a discussion of the assessment of airway obstruction and airway hyperresponsiveness using spirometry. We then review the basics of FOT and its application in respiratory diseases. FOT data are particularly amenable to modeling as an aide to physiological interpretation, and we review several common approaches. This is followed by an in-depth discussion of the assessment of airway variability and heterogeneity using FOT in asthma. Finally, we speculate on the potential clinical utility of FOT in asthma.
Topics: Airway Resistance; Asthma; Humans; Respiration Disorders; Respiratory Function Tests; Respiratory Mechanics; Respiratory System; Spirometry
PubMed: 27278738
DOI: 10.1615/CritRevBiomedEng.v43.i2-3.10 -
Respiratory Physiology & Neurobiology Dec 2021This study aimed to evaluate the accuracy of expiratory time constant (RC) to continuously calculate the airway resistance (R).
BACKGROUND
This study aimed to evaluate the accuracy of expiratory time constant (RC) to continuously calculate the airway resistance (R).
MATERIAL AND METHODS
A Respironics V60 ventilator was connected to a lung simulator for modeling different profiles of respiratory mechanics.
RESULTS
During assisted ventilation, the respiratory system compliance (C) calculation was always overestimated in most lung models. The R estimation using the expiratory resistance (R) method was close to the calculated value with the occlusion method during volume-controlled ventilation (VCV). In expiratory flow limitation (EFL) lung models, similar results were obtained in the estimation of inspiratory resistance (R), but different variations were observed in the calculation of the R. The results estimated with RC and with dynamic signal analysis had significant variation and accuracy (p < 0.001).
CONCLUSION
The RC method is a robust approach to provide real-time assessments of R and R in spontaneously breathing patients during noninvasive ventilation. An underestimation of R was observed in EFL lung models.
Topics: Airway Resistance; Humans; Lung; Models, Biological; Noninvasive Ventilation; Respiratory Mechanics
PubMed: 34242813
DOI: 10.1016/j.resp.2021.103738 -
Respiratory Physiology & Neurobiology Jul 2019Prolonging the therapeutic window for treatment is imperative for survival from a multitude of life-threatening events such as hemorrhage, cardiac arrest, and stroke.... (Review)
Review
Prolonging the therapeutic window for treatment is imperative for survival from a multitude of life-threatening events such as hemorrhage, cardiac arrest, and stroke. Inspiratory resistance breathing is a therapeutic approach that augments the reduction in intrathoracic and intracranial pressure during inspiration, facilitating improvements in vital organ perfusion under conditions of ischemia, such as blood loss and cardiac arrest. In this review a series of studies will be presented assessing the role of inspiratory resistance breathing on responses of cerebral blood flow and cerebral tissue oxygenation under conditions of cardiac arrest and blood loss in animal models, and simulated hemorrhage in humans. Knowledge gaps in this field of investigation will be presented, and future research directions will be discussed.
Topics: Airway Resistance; Animals; Arterial Pressure; Cardiovascular Diseases; Cerebrovascular Circulation; Cerebrum; Hemorrhage; Humans; Intracranial Pressure; Oxygen; Respiration
PubMed: 30340016
DOI: 10.1016/j.resp.2018.10.001 -
The Journal of Laryngology and Otology Jul 2021Electronic cigarettes have been a popular alternative to tobacco smoking. The effect of tobacco smoking on nasal airway resistance has been investigated before; however,...
BACKGROUND
Electronic cigarettes have been a popular alternative to tobacco smoking. The effect of tobacco smoking on nasal airway resistance has been investigated before; however, the effect of the aerosol generated by electronic cigarettes is still unknown. This study aimed to evaluate the short-term effects of e-cigarettes on nasal airway resistance.
METHODS
Sixty-one participants were recruited into a vapers group and a control group. The vapers group was instructed to smoke for 5 minutes, and their nasal resistance was measured pre-procedure and at 1 and 5 minutes post-procedure. The results were compared between both groups.
RESULTS
Repeated measures analysis of variance demonstrated that vaping has no statistically significant effect on total nasal airway resistance.
CONCLUSION
Although the differences between both groups were not statistically significant overall, the vapers group showed a reduction in nasal airway resistance in the short term.
Topics: Adolescent; Adult; Airway Resistance; Case-Control Studies; Cross-Sectional Studies; Electronic Nicotine Delivery Systems; Female; Humans; Male; Middle Aged; Nasal Cavity; Rhinomanometry; Vaping; Young Adult
PubMed: 34078481
DOI: 10.1017/S0022215121001432 -
Medicine Sep 2020Airway compliance is an important index in the surgery of pediatric patients. This study aimed to explore factors affecting dynamic airway compliance (Cdyn) and airway... (Observational Study)
Observational Study
Airway compliance is an important index in the surgery of pediatric patients. This study aimed to explore factors affecting dynamic airway compliance (Cdyn) and airway resistance (Raw) after general anesthesia endotracheal intubation for adenotonsillectomy of pediatric patients.A prospective study was undertaken of 107 children who underwent adenotonsillectomy in Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine between January and June 2018. The values of Cdyn and Raw were recorded at 5, 10, and 15 minute during general anesthesia endotracheal intubation. Univariate analysis and multiple linear regression analysis were performed for factors that affected Cdyn and Raw.Of the 107 patients aged 56.67 ± 18.28 months, 69 (64%) patients were male, and 26 (24%) and 12 (11%) had an upper respiratory infection in the past week and 1 to 2 weeks, respectively. During anesthesia, Cdyn showed a decreasing trend (P < .001) while Raw showed an increasing trend (P < .001). Multivariate analysis revealed that height (β=0.177-0.193) had the strongest correlation with Cdyn; rales during pulmonary auscultation (β= -2.727 to -1.363) and sputum suction (β= -1.670 to -0.949) were also associated with Cdyn (all P < .05). Height was the factor with the strongest negative correlation with Raw (β= -0.382 to -0.305). Rales during pulmonary auscultation (β=10.063-11.326) and sputum suction (β=3.863-9.003) were also associated with Raw (All P < .05).Height, rales during preoperative auscultation and sputum suction were all associated with intraoperative Cydn and Raw for pediatric patients undergoing adenotonsillectomy and should be considered before the surgery.
Topics: Adenoidectomy; Airway Resistance; Anesthesia, General; Auscultation; Body Height; Child; Child, Preschool; Female; Humans; Intubation, Intratracheal; Lung Compliance; Male; Prospective Studies; Respiratory Tract Infections; Tonsillectomy
PubMed: 32899092
DOI: 10.1097/MD.0000000000022101 -
PloS One 2022Obesity can increase the airways resistance, mainly in the periphery, leading to dyspnea perception that can impair the functional capacity. This study aimed to analyze...
BACKGROUND AND OBJECTIVE
Obesity can increase the airways resistance, mainly in the periphery, leading to dyspnea perception that can impair the functional capacity. This study aimed to analyze if airways resistance could be related to the walking capacity of women with morbid obesity.
METHODS
Thirty-seven women with grade III obesity in preoperative bariatric surgery were evaluated using the spirometry test, impulse oscillometry system (IOS), and six-minute walk test (6MWT). Additionally, data about their daily dyspnea perception and physical activity level were collected.
RESULTS
Variables of the spirometry test did not detect ventilator disorders. Compared to the predicted values, the IOS identified significant increase in airways resistance (kPa/L/s) (R5: 0.36 (0.34; 0.36) and 0.53 (0.47; 0.61); R20: 0.30 (0.28; 0.30) and 0.41 (0.35; 0.45); R5-20: 0.06 (0.06; 0.06) and 0.14 (0.10; 0.15); X5: -0.03 (-0.04; -0.01) and -0.20 (-0.27; -0.18), respectively). The distance walked in the 6MWT, 491.4±60.4m was significantly correlated to R5 (rho = -0.41, p = 0.01), R5-20 (rho = -0.52, p = 0.001), and X5 (rho = 0.54, p = 0.0006).
CONCLUSION
The IOS is able to identify changes in airway resistance even before the onset of symptoms. When evaluated by IOS women with severe obesity and normal spirometry exhibited central and peripheral airways obstruction. The correlations between the IOS and six-minute walk distance suggest that increased peripheral airways resistance could be related to worsening functional capacity.
Topics: Airway Resistance; Dyspnea; Female; Forced Expiratory Volume; Humans; Lung; Obesity; Oscillometry; Pulmonary Disease, Chronic Obstructive; Spirometry
PubMed: 35671283
DOI: 10.1371/journal.pone.0267546 -
The Laryngoscope Jan 2022Nasal diseases are among the main motives for the early discontinuation of continuous positive airway pressure therapy and for long-term therapeutic compliance with... (Meta-Analysis)
Meta-Analysis
OBJECTIVE
Nasal diseases are among the main motives for the early discontinuation of continuous positive airway pressure therapy and for long-term therapeutic compliance with mandibular advancement device. Although our clinical experience leads us to the belief that recumbency impacts nasal airflow in some patient populations, there is no consensus regarding the magnitude of this effect and the specific group of patients who are the most affected by this condition. In this study, we conducted a meta-analysis to assess the effect of the recumbent position on nasal resistance and nasal airflow.
REVIEW METHODS
PubMed (Medline), Cochrane Library, EMBASE, Scopus, and SciELO databases were checked for relevant studies by two members of the YO-IFOS study group. The two authors extracted the data. The main outcome was expressed as the difference between nasal resistance and nasal airflow before and after recumbency.
RESULTS
Nine studies with a total population of 291 individuals were included in the meta-analysis for nasal resistance after recumbency. We found a statistically significant difference in nasal airway resistance of -0.18 Pa sec/cm as compared to before and after recumbency through rhinomanometry (RMM) analysis. A subgroup analysis revealed a variation of -0.20 Pa sec/cm for patients with snoring or sleep apnea and - 0.10 Pa sec/cm for healthy individuals. Regarding nasal airflow measured with RMM, three studies (n = 32) in asymptomatic controls revealed a statistically significant difference of 47.33 ml/sec.
CONCLUSIONS
Recumbency increases nasal resistance and diminishes nasal airflow. This finding is of utmost importance in snorers and sleep apnea patients. Laryngoscope, 132:6-16, 2022.
Topics: Airway Resistance; Humans; Nasal Cavity; Supine Position
PubMed: 33720430
DOI: 10.1002/lary.29509 -
Pediatric Pulmonology Nov 2015The forced oscillation technique (FOT) may be affected by the upper airway artifact in children with airway obstruction. The aim was to test the impact of the artifact...
BACKGROUND
The forced oscillation technique (FOT) may be affected by the upper airway artifact in children with airway obstruction. The aim was to test the impact of the artifact on FOT ability to diagnose asthma in children as recommended by current guidelines.
METHODS
The FOT was performed in 58 asthmatics and 27 controls before and after salbutamol. Respiratory resistance (Rrs) was measured at 8 Hz with a standard generator (SG), and a head generator (HG) that minimizes the upper airway artifact. The response to salbutamol was computed as change in respiratory resistance (Δ%Rrs) and admittance (Δ%Ars) that almost cancels the effect of the upper airway artifact.
RESULTS
Rrs and Δ%Rrs were significantly larger in patients than controls by HG (respectively P < 0.001 and P = 0.002) but not SG, while Δ%Ars was larger in asthma than control by both (P < 0.04). Best discriminators between patients and controls were Rrs or Δ%Rrs by HG and Δ%Ars by SG.
CONCLUSION
In asthmatic children, the upper airway artifact significantly impacts FOT measurements. The diagnostic value may be improved by minimization of the shunt, such as the computation of Δ%Ars.
Topics: Airway Obstruction; Airway Resistance; Albuterol; Asthma; Bronchodilator Agents; Child; Female; Humans; Male; Treatment Outcome
PubMed: 25384559
DOI: 10.1002/ppul.23131