Assessment Of Breathing Patterns Research Articles

Inertial Sensors-Based Assessment of Human Breathing Pattern: A Systematic Literature Review

Breathing pattern assessment holds critical importance in clinical practice for detecting respiratory dysfunctions and their impact on health and wellbeing. This systematic literature review investigates the efficacy of inertial sensors in assessing adult human breathing patterns, exploring various methodologies, challenges, and limitations. Utilizing the PSALSAR framework, incorporating the PICOC method and PRISMA statement for comprehensive research, 22 publications were scrutinized from the Scopus, Web of Science, and PubMed databases. A diverse range of sensor fusion methods, data signal analysis techniques, and classifier performances were investigated. Notably, Madgwick’s algorithm and the Principal Component Analysis showed superior performance in tracking respiratory movements. Classifiers like Long Short-Term Memory Recurrent Neural Networks exhibited high accuracy in detecting breathing events. Motion artifacts, limited sample sizes, and physiological variability posed challenges, highlighting the need for further research. Optimal sensor configurations were explored, suggesting improvements with multiple sensors, especially in different body postures. In conclusion, this systematic literature review elucidates methods, challenges, and potential future developments in using inertial sensors for assessing adult human breathing patterns. Overcoming the challenges related to sensor placement, motion artifacts, and algorithm development is essential for progress. Future research should focus on extending sensor applications to clinical settings and diverse populations, enhancing respiratory health management.

Influence of the breathing pattern on the pulmonary function of endurance-trained athletes

Proper functioning of the respiratory system is one of the most important determinants of human health. According to current knowledge, the diaphragmatic breathing pattern seems to be the most favourable. However, recent reports indicate that athletes often have dysfunctional breathing patterns, which may be associated with an increased risk of musculoskeletal injuries. The influence of the type of breathing pattern on the mechanical airways in athletes has not been investigated. The aim of the present study was to determine the characteristics and relationships between breathing patterns and respiratory function in athletes. This study included 69 Polish elite endurance athletes (♂40, ♀29) in different sports disciplines and 44 (♂17, ♀27) healthy nonathletes as a control group. All participants underwent pulmonary function tests (spirometry, plethysmography, diffusion capacity for carbon monoxide) with assessment of breathing patterns by the Hi–Lo test. Inspiratory and expiratory resistance (R) and reactance (X) of the respiratory system at a given frequency (5 Hz, 11 Hz, and 19 Hz) were measured by a noninvasive forced oscillation technique. In this study, almost half of the athletes (44.92%) had dysfunctional breathing patterns, although at a lower rate than that in the control group. Diaphragmatic breathing patterns were characterized by higher spirometric, plethysmographic and DLCO values compared to thoracic or abdominal breathing patterns. Similarly, lower inspiratory reactance at 5 Hz (X5%pred.) was observed in the diaphragmatic pattern compared to the thoracic pattern. A diaphragmatic breathing pattern is associated with better pulmonary function test results. However, this study revealed a dysfunctional breathing pattern in almost half of the athletes. These results suggest that the assessment of breathing patterns and the implementation of breathing exercises in athletes are essential to promote proper breathing patterns.

Towards a better diagnosis of mouth breathing: validity and reliability of a protocol for assessing the awake breathing pattern in preschool children.

The Awake Breathing Pattern Assessment (ABPA) is a prototypical clinical grid recently designed through an international consensus of Speech and Language Pathologists (SLPs) to categorize the awake and habitual breathing pattern during the orofacial myofunctional assessment. This cross-sectional study aims to explore the psychometric properties of the ABPA in a preschool population. 133 children from 2;11 to 6 years old were assessed with the ABPA. The percentage of time spent breathing through the mouth was objectively measured by a CO2 sensor and used as a baseline measurement. We first performed a multivariate Latent Profile Analysis based on the CO2 measurement and a parental questionnaire to define the number of categories that best characterize the breathing pattern. Subsequently, we assessed the intra- and inter-rater reliability, internal consistency criterion validity, construct validity and sensitivity and specificity. The awake breathing pattern can best be described by two groups: nasal and mouth breathing. The ABPA, initially designed in three groups, was adjusted accordingly. This final version showed excellent intra-rater and inter-rater reliability. There was a significant correlation between the ABPA and the CO2 measurement. The ABPA showed a fair sensitivity and a good specificity. The reference tool based on CO2 data was used in children for the first time and was found to be reliable. The ABPA is a suitable tool for SLPs to confirm the diagnosis of mouth breathing in preschool children if more sensitive screening tools, like parental questionnaires, are used beforehand.

Breathing pattern disorder in chronic rhinosinusitis with severe asthma: nasal obstruction and polyps do not increase prevalence

Objectives Chronic rhinosinusitis (CRS) with severe asthma are associated with breathing pattern disorder (BPD). Mouth breathing is a sign of breathing pattern disorder, and nose breathing a fundamental part of breathing pattern retraining for BPD. The prevalence of BPD in relation to CRS subtypes and the relationship of nasal obstruction to BPD in CRS and associated severe asthma is unknown. The breathing pattern assessment tool (BPAT) can identify BPD. Our objective was to thus investigate the prevalence of BPD, nasal airflow obstruction and measures of airway disease severity in CRS with (CRSwNP) and without nasal polyps (CRSsNP) in severe asthma. Methods We determined whether CRS status, peak nasal inspiratory flow (PNIF) or polyp disease increased BPD prevalence. Demographic factors, measures of airway function and breathlessness in relation to BPD status and CRS subtypes were also evaluated. Results 130 Patients were evaluated (n = 69 had BPD). The prevalence of BPD in CRS with severe asthma was 53.1%. There was no difference between BPD occurrence between CRSwNP and CRSsNP. The mean polyp grade and PNIF were not statistically different between the BPD and non-BPD group. The presence of nasal polyps did not increase breathlessness. Conclusions BPD and CRS are commonly co-associated. CRS status and nasal obstruction per se does not increase BPD prevalence.

Assessment of breathing patterns in the context of physical performance in young people

ENWEndNote BIBJabRef, Mendeley RISPapers, Reference Manager, RefWorks, Zotero AMA Kozińska WK, Kuszewski M. Assessment of breathing patterns in the context of physical performance in young people. Physiotherapy Review. 2023;27(1):67-74. doi:10.5114/phr.2023.126012. APA Kozińska, W. K., & Kuszewski, M. (2023). Assessment of breathing patterns in the context of physical performance in young people. Physiotherapy Review, 27(1), 67-74. https://doi.org/10.5114/phr.2023.126012 Chicago Kozińska, Wiktoria K, and Michał Kuszewski. 2023. "Assessment of breathing patterns in the context of physical performance in young people". Physiotherapy Review 27 (1): 67-74. doi:10.5114/phr.2023.126012. Harvard Kozińska, W., and Kuszewski, M. (2023). Assessment of breathing patterns in the context of physical performance in young people. Physiotherapy Review, 27(1), pp.67-74. https://doi.org/10.5114/phr.2023.126012 MLA Kozińska, Wiktoria et al. "Assessment of breathing patterns in the context of physical performance in young people." Physiotherapy Review, vol. 27, no. 1, 2023, pp. 67-74. doi:10.5114/phr.2023.126012. Vancouver Kozińska W, Kuszewski M. Assessment of breathing patterns in the context of physical performance in young people. Physiotherapy Review. 2023;27(1):67-74. doi:10.5114/phr.2023.126012.

Identification of Breathing Pattern Disorder in Athletes With Exercise-Induced Laryngeal Obstruction: A Novel Assessment Tool

To report the diagnostic utility of the novel, high-ventilatory task assessment tool called the Milstein Breathing Pattern Assessment Index (M-BPAI) for evaluation of Breathing Pattern Disorder (BPD) in athletes with and without breathing difficulty, and to evaluate the prevalence of BPD in athletes referred for Exercise Induced Laryngeal Obstruction (EILO). BPD is an abnormal respiratory biomechanical pattern caused from functional or structural factors. The presence of BPD in athletes with EILO is unknown. The current clinical evaluations of dysfunctional breathing patterns are limiting for evaluation of BPD in patients with EILO, as these only evaluate the patients in low ventilatory output tasks of rest breathing. In this prospective study, a total of 77 athletes referred to the clinic for suspected EILO and 58 athletes without any respiratory difficulty underwent M-BPAI assessment. Data collection from the experimental group also included the Dyspnea Index, and laryngeal video endoscopic provocation test. The M-BPAI score was significantly larger in the patient group compared to the control group. An overall M-BPAI score of ≥8 corresponds to the AUC of 0.87 (95% CI: 0.81-0.93) with a sensitivity of 0.862 and specificity of 0.792. A total of 60 (78%) patients had an overall M-BPAI score of ≥8. The M-BPAI has the potential to be a valuable clinical diagnostic marker for identifying BPD in patients with suspected EILO with further research and validation.

Nurses' role in the management of persons with chronic urogenital pelvic pain syndromes: A scoping review.

Pelvic pain has cognitive, behavioral, sexual, and emotional consequences. Nurses involved in pelvic floor rehabilitation clinics have contacts with patients reporting chronic pain and should know the most appropriate service for patient referral, to submit the problem to professionals capable of correctly assessing and managing the condition. Furthermore, in some countries nurses can use conservative methods to treat the painful symptoms inside a multidisciplinary team such as breathing retraining, biofeedback, and noninvasive neuromodulation. This paper aims to provide an overview of the literature regarding the role of rehabilitation nurses in dealing with patients suffering from chronic urogenital pelvic pain or urogenital painful syndromes, inside a multidisciplinary team. Scoping review on Pubmed, CINAHL, Embase, Scopus, Web of Science including trials, reviews, case studies or series, and other descriptive studies regarding the role of nurses inside the multidisciplinary team in the management of males and females presenting chronic pelvic pain (CPP) or chronic pelvic pain syndrome(CPPS). The 36 papers included in this review allowed answering research questions in four areas of nursing: collecting basic information, referring the person to appropriate services, evidence-based nursing interventions for CPPand CPPS, and proper documentation. Clinical history and assessment of breathing pattern, Muscular assessment and research of trigger points are the main points of data collection. Techniques for muscular relaxation and breathing retraining are important aspects of treatment, as well as biofeedback and noninvasive neuromodulation where the law allows nurses to practice such techniques. The McGill pain questionnaire and the pain inventory of the International Pain Society allow systematic data collection and handover. Rehabilitation nurses work inside multidisciplinary teams when dealing with persons suffering from pelvic pain; further research is needed as our comprehension of the underlying pathophysiological mechanisms of CPPand CPPS evolve.

Real-world use of the Breathing Pattern Assessment Tool in assessment of breathlessness post-COVID-19

Breathing pattern disorders (BPDs) are a common cause of chronic breathlessness, including after acute respiratory illnesses such as COVID pneumonia. BPD is however underdiagnosed, partly as a result of difficulty in clinically assessing breathing pattern. The Breathing Pattern Assessment Tool (BPAT) has been validated for use in diagnosing BPD in patients with asthma but to date has not been validated in other diseases. Patients undergoing face-to-face review in a post-COVID clinic were assessed by a respiratory physician and specialist respiratory physiotherapist. Assessment included a Dyspnoea-12 (D12) questionnaire to assess breathlessness, physiotherapist assessment of breathing pattern including manual assessment of respiratory motion, and BPAT assessment. The sensitivity and specificity of BPAT for diagnosis of BPD in post-COVID patients was assessed. BPAT had a sensitivity of 89.5% and specificity of 78.3% for diagnosing BPD in post-COVID breathlessness. Patients with a BPAT score above the diagnostic cut-off had higher levels of breathlessness than those with lower BPAT scores (D12 score mean average 19.4 vs 13.2). BPAT has high sensitivity and moderate specificity for BPD in patients with long COVID. This would support its use as a screening test in clinic, and as a diagnostic tool for large cohort studies.

To Assess the Effectiveness of Selected Breathing Exercises among Chronic Obstructive Pulmonary Disease Patients

Mortality rate of chronic obstructive pulmonary disease (COPD) is more than 3 million people every year, making it 3rd largest cause of death in the world. It has been estimated that by the year 2030. chronic obstructive pulmonary disease will become the third biggest cause of death. chronic obstructive pulmonary disease (COPD) is a progressive irreversible airway disease characterized by emphysema and chronic bronchitis, resulting in breathlessness, cough and sputum as the disease progresses, subjects with COPD experience increasing deterioration of their health-related quality of life (HRQOL), with greater impairment in their ability to work and declining participation in social and physical activities. Hence practicing pursed lip breathing exercise in their daily routine will improve their breathing pattern and quality of life.
 Objectives:
 
 To assess the breathing pattern of chronic obstructive pulmonary disease patient.
 To assess the effectiveness of selected breathing exercises among the chronic obstructive pulmonary disease patients.
 To associate the effectiveness of selected breathing exercises among chronic obstructive pulmonary disease patient with their demographic variables.
 
 Materials and Methods: The research approach used for the study was interventional evaluatory approach. The study was conducted in respiratory unit at Wardha City Maharashtra, India, using one group pre test post test design without control group. Non probability purposive sampling technique was used for selecting 60 COPD patients. On the first day pre test assessment of breathing pattern with the help of borg rating scale and provided pursed lip breathing exercise for 20 minutes, 2 times in a day and it was continued for 15 days followed by post test on the 15th day. The data collected, tabulated and analysed in terms of objectives of study using descriptive and inferential statistics.
 Results: The mean post test score. The overall comparison of selected breathing exercise among COPD patients at rest pre test score was higher 3.48 with SD of ±1.25 when compare with at rest post test score which was 0.91 with SD of ±0.85.The statistical Student’s paired t test implies that the difference in the selected breathing exercise among COPD patients was found to be 18.98 which is statistically significant at 0.05% level of significance. Also the overall comparison of selected breathing exercise among COPD patients during activity pre test score was higher 7.95 with SD of ±1.50 when compared with during activity post test score which was 2.76 with SD of ±1.02. The statistical Student’s paired t test implies that the difference in the selected breathing exercise among COPD patients was found to be 18.98 which is statistically significant at 0.05% level of significance. Hence it is statistically interpreted that effectiveness of selected breathing exercises among COPD patients at rest and during activity in post test was effective. The tabulated values was much higher than the calculated’ values at 5% level of significance, also the calculated ‘p-value which was much higher than the acceptable level of significance i.e. ‘p’=0.05. Hence the association of effectiveness of selected breathing exercises is statistically not associated with demographic variables.
 Conclusion: According to the results of this study, patients with Chronic Obstructive Pulmonary disease patients who practiced pursed lip breathing exercise 20 minutes, 2 times a day for 15 days had improvement of the breathing pattern which was statistically proved. Hence pursed lip breathing exercise was cost effective, non invasive, and highly feasible. Hence the researcher concluded that pursed lip breathing exercise can be practice as an effective intervention on improving breathing pattern among chronic obstructive pulmonary disease patients.

Automated Classification of Whole Body Plethysmography Waveforms to Quantify Breathing Patterns

Whole body plethysmography (WBP) monitors respiratory rate and depth but conventional analysis fails to capture the diversity of waveforms. Our first purpose was to develop a waveform cluster analysis method for quantifying dynamic changes in respiratory waveforms. WBP data, from adult Sprague-Dawley rats, were sorted into time domains and principle component analysis was used for hierarchical clustering. The clustering method effectively sorted waveforms into categories including sniffing, tidal breaths of varying duration, and augmented breaths (sighs). We next used this clustering method to quantify breathing after opioid (fentanyl) overdose and treatment with ampakine CX1942, an allosteric modulator of AMPA receptors. Fentanyl caused the expected decrease in breathing, but our cluster analysis revealed changes in the temporal appearance of inspiratory efforts. Ampakine CX1942 treatment shifted respiratory waveforms toward baseline values. We conclude that this method allows for rapid assessment of breathing patterns across extended data recordings. Expanding analyses to include larger portions of recorded WBP data may provide insight on how breathing is affected by disease or therapy.

Enhanced Breathing Pattern Detection during Running Using Wearable Sensors.

Breathing pattern (BP) is related to key psychophysiological and performance variables during exercise. Modern wearable sensors and data analysis techniques facilitate BP analysis during running but are lacking crucial validation steps in their deployment. Thus, we sought to evaluate a wearable garment with respiratory inductance plethysmography (RIP) sensors in combination with a custom-built algorithm versus a reference spirometry system to determine its concurrent validity in detecting flow reversals (FR) and BP. Twelve runners completed an incremental running protocol to exhaustion with synchronized spirometry and RIP sensors. An algorithm was developed to filter, segment, and enrich the RIP data for FR and BP estimation. The algorithm successfully identified over 99% of FR with an average time lag of 0.018 s (−0.067,0.104) after the reference system. Breathing rate (BR) estimation had low mean absolute percent error (MAPE = 2.74 [0.00,5.99]), but other BP components had variable accuracy. The proposed system is valid and practically useful for applications of BP assessment in the field, especially when measuring abrupt changes in BR. More studies are needed to improve BP timing estimation and utilize abdominal RIP during running.

Classification and Detection of Breathing Patterns with Wearable Sensors and Deep Learning.

Rapid assessment of breathing patterns is important for several emergency medical situations. In this research, we developed a non-invasive breathing analysis system that automatically detects different types of breathing patterns of clinical significance. Accelerometer and gyroscopic data were collected from light-weight wireless sensors placed on the chest and abdomen of 100 normal volunteers who simulated various breathing events (central sleep apnea, coughing, obstructive sleep apnea, sighing, and yawning). We then constructed synthetic datasets by injecting annotated examples of the various patterns into segments of normal breathing. A one-dimensional convolutional neural network was implemented to detect the location of each event in each synthetic dataset and to classify it as belonging to one of the above event types. We achieved a mean F1 score of 92% for normal breathing, 87% for central sleep apnea, 72% for coughing, 51% for obstructive sleep apnea, 57% for sighing, and 63% for yawning. These results demonstrate that using deep learning to analyze chest and abdomen movement data from wearable sensors provides an unobtrusive means of monitoring the breathing pattern. This could have application in a number of critical medical situations such as detecting apneas during sleep at home and monitoring breathing events in mechanically ventilated patients in the intensive care unit.

The impact of dysfunctional breathing on the level of asthma control in difficult asthma.

Difficult asthma is defined as asthma requiring high dose treatment. However, systematic assessment is required to differentiate severe asthma from difficult-to-treat asthma. Dysfunctional breathing (DB) is a common comorbidity in difficult asthma, which may contribute to symptoms, but how it affects commonly used measures of symptom control is unclear. All adult asthma patients seen in four respiratory clinics over one year were screened prospectively, and patients with possible severe asthma according to ERS/ATS criteria ('Difficult asthma': high-dose inhaled corticosteroids/oral corticosteroids), underwent systematic assessment. Symptoms of DB were assessed utilizing a symptom based subjective tool, Nijmegen questionnaire (NQ), and objective signs of DB with the Breathing Pattern Assessment Tool (BPAT). Asthma control and quality of life were evaluated with the Asthma Control Questionnaire (ACQ) and the mini Asthma Quality of Life Questionnaire (AQLQ). A total of 117 patients were included. Among these, 29.9% (35/117) had DB according to the NQ. Patients with DB had a poorer asthma control (ACQ: Mean (SD) 2.86±1.05 vs. 1.46±0.93) and lower quality of life (AQLQ score: Mean (SD) 4.2±1.04 vs. 5.49±0.85) compared to patients without DB. Similarly, patients with objective signs of DB according to the BPAT score had worse asthma control: BPAT >4 vs<4: (ACQ: Mean (SD) 3.15±0.93 vs 2.03±1.15). DB is common among patients with difficult asthma, and is associated with significantly poorer asthma control and lower quality of life. Assessment and treatment of DB is an important part of the management of difficult asthma.

Effect of continuous positive airway pressure on respiratory drive in patients with obstructive sleep apnea

ObjectivePatients with obstructive sleep apnea (OSA) have an altered control of breathing during wakefulness. Thus far, whether and how treatment with continuous positive airway pressure (CPAP) may restore these abnormalities has been poorly understood. The aim of this study was to investigate the long-term effects of CPAP on the breathing pattern, ventilatory drive (VDr), and chemoreceptor sensitivity in OSA patients. Patients and methodsThis was a prospective, observational study, carried out in an academic sleep outpatient clinic. A total of 62 patients with OSA (mean age [SD], 51 [11] years) underwent polysomnography (PSG), breathing pattern assessment, mouth occlusion pressure, ventilatory response to hypoxemia (Ve/SaO2), and hypercapnia (Ve/PETCO2) before and after CPAP titration and during 12-month follow-up. A total of 48 age-matched healthy subjects served as controls. Patients with good (≥6 h/night) and poor (<6 h/night) compliance with CPAP were also compared. ResultsAt baseline, VDr as well as thoracic and inspiratory impedances were greater in patients with OSA compared with controls and were reduced by CPAP treatment, starting from the night of titration (P < 0.01), especially in patients with good compliance with CPAP. Baseline Ve/SaO2 was higher in OSA patients (P < 0.05) and was progressively normalized during CPAP treatment (P < 0.001). The pathophysiological changes were mainly due to a reduction in tidal volume. The remaining breathing pattern parameters were unaltered by CPAP treatment and were similar between groups. ConclusionIn OSA patients, the mechanics of breathing are inefficient because of an imbalance of the VDr. Regular CPAP treatment improves the efficiency of the respiratory system and normalizes the hypoxemic stimulus.

Unbiased analysis of plethysmography waveforms during opioid‐induced hypoventilation in rats

Whole body plethysmography chambers enable collection of respiratory waveform data from unrestrained and unanesthetized animals. However, the recorded waveforms are dynamically changing and stochastic. Indeed, awake and freely behaving mammals do not breathe with the metronomic patterns studied under anesthesia or in vitro. Typically, in plethysmography experiments, large portions of recorded data are omitted from analysis in favor of arbitrarily defined periods of “stable breathing”. The goals of the current study are 1) to develop a method for unbiased assessment of all waveforms recorded during whole body plethysmography, and 2) to use this method to comprehensively assess breathing patterns following opioid overdose. The rationale being that opioid overdose is a major public health crisis, and many researchers are using rodent models to study the impact of opioids on breathing. We reasoned that detailed analyses of breathing waveforms (i.e., beyond typical assessment of rate and depth) could provide insights into the impact of opioids on the respiratory neuromuscular system. Plethysmography data were recorded from male Sprague Dawley rats (n = 8; 379±24g) using a Buxco Finepointe system. Following an extended period of baseline breathing, fentanyl was administered intravenously until tidal volume was reduced to 50% of baseline values. The required fentanyl dose varied, and ranged from 60–240μg/kg. MATLAB software was written to detect distinct waveforms. Waveforms which crossed a threshold were grouped into four time domains based on duration: 0–0.2s, 0.2–0.5s, 0.5–1.2s, and 1.2–4s. Principle component analysis reduced the dimensionality, and a hierarchical linkage tree was constructed to group the waveforms into clusters. Within each time domain the linkage tree was restricted to 2, 5, 5, and 3 clusters based on the expected variability of breath shapes within each time domain. These waveforms encompassed respiratory‐related behaviors including sniff, tidal breathing, and sigh. We next quantified the frequency of these 15 waveforms during baseline, the entire period of fentanyl infusion (F‐entire), and during the last 5‐min of the fentanyl exposure when ventilation was at its nadir (F‐end). During F‐end, the larger amplitude, short time scale waveform occurred 8% as often compared to baseline. The occurrence of four of the five 0.2–0.5s duration waveforms was reduced during F‐end; however, we also observed a 209% increase in the occurrence of a distinct low amplitude waveform. Similarly three of the five waveforms in the 0.5–1.2s time domain occurred less often during F‐end, one was unchanged and the incidence of one waveform increased by 4446%. Interestingly, the incidence of this cluster during F‐entire increased by 1938% suggesting the presence of this waveform could indicate oncoming respiratory decline. We conclude that respiratory waveform cluster analysis allows for rapid unbiased assessment of breathing patterns during instances of hypoventilation. This analysis can provide insight into how the neuromotor respiratory system is affected by drugs, disease, or injury.Support or Funding InformationT32‐HD043730 (MDS). SPARC OT2 OD0238541 R01 NS080180‐01A1 (DDF)This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Diagnosis of the Hypopnea syndrome in the early stage

Hypopnea syndrome is a chronic respiratory disease that is characterized by repetitive episodes of breathing disruptions during sleep. Hypopnea syndrome is a systemic disease that manifests respiratory problems; however, more than 80% of Hypopnea syndrome patients remain undiagnosed due to complicated polysomnography. Objective assessment of breathing patterns of an individual can provide useful insight into the respiratory function unearthing severity of Hypopnea syndrome. This paper explores a novel approach to detect incognito Hypopnea syndrome as well as provide a contactless alternative to traditional medical tests. The proposed method is based on S-Band sensing technique (including a spectrum analyzer, vector network analyzer, antennas, software-defined radio, RF generator, etc.), peak detection algorithm and Sine function fitting for the observation of breathing patterns and characterization of normal or disruptive breathing patterns for Hypopnea syndrome detection. The proposed system observes the human subject and changes in the channel frequency response caused by Hypopnea syndrome utilizing a wireless link between two monopole antennas, placed 3 m apart. Commercial respiratory sensors were used to verify the experimental results. By comparing the results, it is found that for both cases, the pause time is more than 10 s with 14 peaks. The experimental results show that this technique has the potential to open up new clinical opportunities for contactless and accurate Hypopnea syndrome monitoring in a patient-friendly and flexible environment.

Novel assessment tool to detect breathing pattern disorder in patients with refractory asthma.

Breathing pattern disorder (BPD) can co-exist with and mimic asthma, acting to amplify symptoms and confound assessment of disease control, resulting in inappropriate treatment escalation. The aim of this research was to report the utility of a novel breathing pattern assessment tool (BPAT) to detect BPD in treatment-refractory asthma. As a component of a multidisciplinary assessment, adult patients referred with treatment-refractory asthma underwent respiratory physiotherapy assessment to diagnose BPD. Based on this assessment, patients were classified as having asthma, asthma + BPD or BPD alone. BPAT data were collected in addition to questionnaire data (Asthma Quality of Life Questionnaire (AQLQ) and Nijmegen Questionnaire (NQ)), pulmonary function and an assessment of exercise capacity. Data were retrospectively analysed for 150 (female; 69%) patients, mean (SD) age of 43 (14) years; characterized as asthma-only (n = 54, 36%), asthma + BPD (n = 63, 42%) and BPD-only (n = 33, 22%). Of the total population, 113 (76%) had an NQ score ≥23, but of these only 68% had physiotherapy evidence of BPD. Exercise capacity and AQLQ were lower in the asthma + BPD group than in the asthma-only group (P < 0.05), whilst lung function was similar between groups. Sensitivity analysis indicated that a BPAT score of ≥4 corresponded to a sensitivity of 0.92 and a specificity of 0.75 for diagnosis of BPD in this cohort. Breathing pattern irregularities are highly prevalent in individuals referred with treatment-refractory asthma and can be characterized using the BPAT. Further work is needed to determine inter-observer and within-subject variability and ensure the BPAT is a robust clinical tool. Watch the video abstract.

Measuring Ventilatory Activity with Structured Light Plethysmography (SLP) Reduces Instrumental Observer Effect and Preserves Tidal Breathing Variability in Healthy and COPD.

The use of a mouthpiece to measure ventilatory flow with a pneumotachograph (PNT) introduces a major perturbation to breathing (“instrumental/observer effect”) and suffices to modify the respiratory behavior. Structured light plethysmography (SLP) is a non-contact method of assessment of breathing pattern during tidal breathing. Firstly, we validated the SLP measurements by comparing timing components of the ventilatory pattern obtained by SLP vs. PNT under the same condition; secondly, we compared SLP to SLP+PNT measurements of breathing pattern to evaluate the disruption of breathing pattern and breathing variability in healthy and COPD subjects. Measurements were taken during tidal breathing with SLP alone and SLP+PNT recording in 30 COPD and healthy subjects. Measurements included: respiratory frequency (Rf), inspiratory, expiratory, and total breath time/duration (Ti, Te, and Tt). Passing-Bablok regression analysis was used to evaluate the interchangeability of timing components of the ventilatory pattern (Rf, Ti, Te, and Tt) between measurements performed under the following experimental conditions: SLP vs. PNT, SLP+PNT vs. SLP, and SLP+PNT vs. PNT. The variability of different ventilatory variables was assessed through their coefficients of variation (CVs). In healthy: according to Passing-Bablok regression, Rf, TI, TE and TT were interchangeable between measurements obtained under the three experimental conditions (SLP vs. PNT, SLP+PNT vs. SLP, and SLP+PNT vs. PNT). All the CVs describing “traditional” ventilatory variables (Rf, Ti, Te, Ti/Te, and Ti/Tt) were significantly smaller in SLP+PNT condition. This was not the case for more “specific” SLP-derived variables. In COPD: according to Passing-Bablok regression, Rf, TI, TE, and TT were interchangeable between measurements obtained under SLP vs. PNT and SLP+PNT vs. PNT, whereas only Rf, TE, and TT were interchangeable between measurements obtained under SLP+PNT vs. SLP. However, most discrete variables were significantly different between the SLP and SLP+PNT conditions and CVs were significantly lower when COPD patients were assessed in the SLP+PNT condition. Measuring ventilatory activity with SLP preserves resting tidal breathing variability, reduces instrumental observer effect and avoids any disruptions in breathing pattern induced by the use of PNT-mouthpiece-nose-clip combination.

Prediction of the Chemoreflex Gain by Common Clinical Variables in Heart Failure.

BackgroundPeripheral and central chemoreflex sensitivity, assessed by the hypoxic or hypercapnic ventilatory response (HVR and HCVR, respectively), is enhanced in heart failure (HF) patients, is involved in the pathophysiology of the disease, and is under investigation as a potential therapeutic target. Chemoreflex sensitivity assessment is however demanding and, therefore, not easily applicable in the clinical setting. We aimed at evaluating whether common clinical variables, broadly obtained by routine clinical and instrumental evaluation, could predict increased HVR and HCVR.Methods and results191 patients with systolic HF (left ventricular ejection fraction—LVEF—<50%) underwent chemoreflex assessment by rebreathing technique to assess HVR and HCVR. All patients underwent clinical and neurohormonal evaluation, comprising: echocardiogram, cardiopulmonary exercise test (CPET), daytime cardiorespiratory monitoring for breathing pattern evaluation. Regarding HVR, multivariate penalized logistic regression, Bayesian Model Averaging (BMA) logistic regression and random forest analysis identified, as predictors, the presence of periodic breathing and increased slope of the relation between ventilation and carbon dioxide production (VE/VCO2) during exercise. Again, the above-mentioned statistical tools identified as HCVR predictors plasma levels of N-terminal fragment of proBNP and VE/VCO2 slope.ConclusionsIn HF patients, the simple assessment of breathing pattern, alongside with ventilatory efficiency during exercise and natriuretic peptides levels identifies a subset of patients presenting with increased chemoreflex sensitivity to either hypoxia or hypercapnia.

Age Effects on Blood Gas, Spirometry, Airway Reactivity, and Bronchoalveolar Lavage Fluid Cytology in Clinically Healthy Horses

BackgroundDespite the increasing number of geriatric horses attended by veterinarians, there is a lack of understanding of aging‐related changes on the respiratory system of horses.ObjectiveTo identify aging‐related changes on the respiratory function and bronchoalveolar lavage fluid (BALF) cytology of horses.AnimalsFifteen healthy young adult (2–11 years) and 16 healthy aged (≥20 years) horses.MethodsThe respiratory system was examined by measurement of arterial blood gases (ABG), use of respiratory inductive plethysmography (RIP) for assessment of breathing pattern and ventilatory parameters, histamine bronchoprovocation, and BALF cytology.ResultsNo significant differences were detected with regard to values obtained by ABG or bronchoprovocation of young adult and aged healthy horses. In aged horses, there were significant differences in mean ± SD of the following parameters when compared to young horses: prolonged expiratory time (Te) measured by RIP (3.9 ± 1.5 s versus 3.0 ± 0.6 s), decreased percentage of alveolar macrophages (40.6 ± 11.3% versus 53.5 ± 9.6%), and increased percentage of lymphocytes (53.4 ± 9.5% versus 43.9 ± 11.0%). No correlations between airway reactivity and ventilatory parameters, ABG, or BALF cytology were found in this asymptomatic population.ConclusionsThese results suggest that aging does not cause changes in the results obtained by ABG, most RIP‐derived variables, and bronchoprovocation in the horse. A decreased percentage of macrophage and an increased percentage of lymphocytes in the BALF cytology may be expected in the asymptomatic geriatric horse and may be a result of aging.