-
Frontiers in Medicine 2024Sulfur mustard (SM) exposure causes acute and chronic respiratory diseases. The extent of small airway dysfunction (SAD) in individuals exposed to SM is unclear. This...
BACKGROUND
Sulfur mustard (SM) exposure causes acute and chronic respiratory diseases. The extent of small airway dysfunction (SAD) in individuals exposed to SM is unclear. This study evaluated and compared SAD in SM-exposed and SM-unexposed participants using noninvasive lung function tests assessing small airway function.
METHODS
This retrospective cohort study involved SM-exposed ( = 15, mean age: 53 ± 8 years) and SM-unexposed ( = 15, mean age: 53 ± 7 years) Kurdish-Swedish individuals in Sweden. Small airway resistance and reactance were assessed using impulse oscillometry (IOS). Nitrogen (N) multiple breath washout (MBW) was employed to assess lung ventilation heterogeneity. The gas-exchanging capacity of the lungs was assessed using the diffusing capacity of the lungs for the carbon monoxide (DLCO) test. Lung function outcomes were reported as absolute values and -scores. Group comparisons were performed using the Mann-Whitney U test.
RESULTS
No statistically significant differences in age, height, or body mass index were observed between the two groups. IOS showed significantly increased small airway resistance, while NMBW exhibited significantly increased global and acinar ventilation heterogeneity in SM-exposed individuals compared to that in unexposed individuals. SAD was identified in 14 of 15 SM-exposed individuals, defined as at least one abnormal IOS difference between resistance at 5 and 20 Hz (R5-R20) and/or area of reactance (AX) or NMBW lung's acinar zone (S), and DLCO adjusted to the alveolar volume (DLCO/VA) outcome. Of these 14 individuals, only 5 demonstrated concordant findings across the IOS and NMBW tests.
CONCLUSION
Exposure to SM was positively associated with long-term impairment of respiratory tract function in the small airways in the majority of the previously SM-exposed individuals in the present study. Furthermore, both IOS and NMBW should be employed to detect SAD in SM-exposed survivors as they provide complementary information. Identifying and characterizing the remaining pathology of the small airways in survivors of SM exposure is a first step toward improved treatment and follow-up.
PubMed: 38500955
DOI: 10.3389/fmed.2024.1251500 -
Clinics (Sao Paulo, Brazil) 2024Studies suggest peripheral airway abnormalities in Pulmonary Arterial Hypertension (PAH). Impulse Oscillometry (IOS) is a noninvasive and sensitive technique for...
INTRODUCTION
Studies suggest peripheral airway abnormalities in Pulmonary Arterial Hypertension (PAH). Impulse Oscillometry (IOS) is a noninvasive and sensitive technique for assessing the small airways. It evaluates the impedance of the respiratory system ‒ Resistance (R) and reactance (X) ‒ to a pulse of sound waves sent to the lungs, in a range of frequencies (5‒20 Hz).
METHOD
Resistance variables: R5, R20, R5-R20 and reactance variables: AX (reactance area) and Fres (resonance frequency). The aim is to evaluate R and X in patients with idiopathic PAH (IPAH) and to investigate whether there is a correlation between IOS and spirometry.
RESULTS
Thirteen IPAH patients and 11 healthy subjects matched for sex and age underwent IOS and spirometry. IPAH patients had lower FVC and FEV values (p < 0.001), VEF/CVF (p = 0.049) and FEF 25-75 (p = 0.006) than healthy patients. At IOS, IPAH patients showed lower tidal volumes and higher AX (p < 0.05) compared to healthy individuals, and 53.8 of patients had R5-R20 values ≥ 0.07 kPa/L/s. Correlation analysis: X5, AX, R5-R20 and Fres showed moderate correlation with FVC (p = 0.036 r = 0.585, p = 0.001 r = -0.687, p = 0.005 r = -0.726 and p = 0.027 r = -0.610); Fres (p = 0.012 r = -0.669) and AX (p = 0.006 r = -0.711) correlated with FEV; [R5 and R20, (R5-R20)] also correlated with FEV (p < 0.001 r = -0.573, p = 0.020 r = -0.634 and p = 0.010 r = -0.683, respectively) in the IPAH group. There were also moderate correlations of FEF 25-75 % with Z5 (p = 0.041), R5 (p = 0.018), Fres (p = 0.043) and AX (p = 0.023).
DISCUSSION
Patients showed changes suggestive of increased resistance and reactance in the IOS compared to healthy individuals, and the IOS findings showed a good correlation with spirometry variables.
Topics: Humans; Pulmonary Arterial Hypertension; Oscillometry; Forced Expiratory Volume; Respiratory Function Tests; Lung; Spirometry
PubMed: 38490138
DOI: 10.1016/j.clinsp.2023.100313 -
International Journal of Chronic... 2024Chronic obstructive pulmonary disease (COPD) phenotypes may introduce different characteristics that need to be known to improve treatment. Respiratory oscillometry...
PURPOSE
Chronic obstructive pulmonary disease (COPD) phenotypes may introduce different characteristics that need to be known to improve treatment. Respiratory oscillometry provides a detailed analysis and may offer insight into the pathophysiology of COPD. In this paper, we used this method to evaluate the differences in respiratory mechanics of COPD phenotypes.
PATIENTS AND METHODS
This study investigated a sample of 83 volunteers, being divided into control group (CG = 20), emphysema (n = 23), CB (n = 20) and asthma-COPD overlap syndrome (ACOS, n = 20). These analyses were performed before and after bronchodilator (BD) use. Functional capacity was evaluated using the Glittre‑ADL test, handgrip strength and respiratory pressures.
RESULTS
Initially it was observed that oscillometry provided a detailed description of the COPD phenotypes, which was consistent with the involved pathophysiology. A correlation between oscillometry and functional capacity was observed (r=-0.541; p = 0.0001), particularly in the emphysema phenotype (r = -0.496, p = 0.031). BD response was different among the studied phenotypes. This resulted in an accurate discrimination of ACOS from CB [area under the receiver operating curve (AUC) = 0.84] and emphysema (AUC = 0.82).
CONCLUSION
These results offer evidence that oscillatory indices may enhance the comprehension and identification of COPD phenotypes, thereby potentially improving the support provided to these patients.
Topics: Humans; Pulmonary Disease, Chronic Obstructive; Lung; Asthma; Oscillometry; Hand Strength; Forced Expiratory Volume; Pulmonary Emphysema; Emphysema; Bronchodilator Agents; Phenotype; Physical Functional Performance
PubMed: 38464561
DOI: 10.2147/COPD.S446085 -
Biomedical Engineering Online Mar 2024Persons with asthma may experience excessive airway narrowing due to exercise or exposure to cold air, worsening their daily functionality. Exercise has several benefits...
BACKGROUND
Persons with asthma may experience excessive airway narrowing due to exercise or exposure to cold air, worsening their daily functionality. Exercise has several benefits for asthma control, but it may induce airway narrowing in some persons with asthma. When combined with cold temperatures, it introduces another layer of challenges. Therefore, managing this interaction is crucial to increase the quality of life in individuals with asthma. The purpose of this study was to develop a reliable experimental protocol to assess the effects of exercise and cold air on airway narrowing in adults with asthma in a controlled and safe environment.
METHODS
This study was a randomized cross-over study in adults with and without asthma. Participants underwent a protocol involving a 10-min seated rest, followed by a 10-min cycling on a stationary bike in different temperatures of 0, 10, or 20 C. The sequence of room temperatures was randomized, and there was a 30-min interval for recovery between each temperature transition. In each temperature, to measure lung function and respiratory symptoms, oscillometry and a questionnaire were used at 0 min (baseline), after 10 min of sitting and before starting biking (pre-exercise), and after 10 min of biking (post-exercise). At each room temperature, the changes in airway mechanics and asthma symptoms among baseline, pre-exercise, and post-exercise were compared with one-way repeated measures ANOVA or Friedman Rank Test. Within each arm, cardiac and thoraco-abdominal motion respiration signals were also measured continuously using electrodes and calibrated respiratory inductance plethysmographs, respectively.
RESULTS
A total of 23 persons with asthma (11 females, age: 56.3 ± 10.9 years, BMI: 27.4 ± 5.7 kg/m) and 6 healthy subjects (3 females, age: 61.8 ± 9.1 years, BMI: 28.5 ± 3.1 kg/m) were enrolled in the study. Cold temperature of 0 C induced airway narrowing in those with and without asthma after 10 and 20 min, respectively. Exercise intervention had significant changes in airway narrowing in participants with asthma in the range of 10-20 C. Our results showed that in asthma, changes in subjective respiratory symptoms were due to both cold temperatures of 0 and 10 C and exercise in the 0-20 C range. Respiratory symptoms were not noticed among the healthy participants.
CONCLUSION
In conclusion, our findings suggest that exposure to cold temperatures of 0 C could serve as a reliable method in the experimental protocol for inducing airway narrowing in asthma. The impact of exercise on airway narrowing was more variable among participants. Understanding these triggers in the experimental protocol is essential for the successful management of asthma in future studies.
Topics: Female; Humans; Aged; Middle Aged; Quality of Life; Asthma; Cold Temperature; Respiration; Temperature; Randomized Controlled Trials as Topic
PubMed: 38448963
DOI: 10.1186/s12938-023-01197-6 -
American Journal of Veterinary Research May 2024To investigate whether pulse-wave analysis (PWA) performed by trained evaluators facilitates detection of nonsinus rhythm.
OBJECTIVE
To investigate whether pulse-wave analysis (PWA) performed by trained evaluators facilitates detection of nonsinus rhythm.
ANIMALS
Same-day, high-definition oscillometry pulse-wave data and ECG results of 155 animals (144 dogs and 11 cats) were analyzed.
METHODS
In this cross-sectional study, we enrolled 18 participants from various backgrounds, all of whom received PWA training. The ability to distinguish between sinus and nonsinus rhythms was assessed using receiver operating characteristic curve analysis. The pulse-wave datasets were divided into 5 ECG categories. Agreement between ECG diagnoses and PWA-based arrhythmia detection was evaluated using Cohen κ values, and the correlation between the academic year of veterinary students and their κ values was assessed.
RESULTS
All cardiology researchers demonstrated satisfactory accuracy in distinguishing pathological rhythms using PWA (area under the curve, 0.704 to 0.761), with the highest accuracy in detecting atrial fibrillation (area under the curve, 0.811 to 0.845). Fair agreement with ECG categorization was achieved by all 3 cardiology researchers, 2 of 5 general practitioners, and 3 of 10 veterinary undergraduates. The veterinary undergraduates' years of study were correlated with their diagnostic performance (Spearman ρ = 0.658; P = .019).
CLINICAL RELEVANCE
PWA during routine noninvasive blood pressure measurement showed significant potential for the detection of pathological arrhythmias, notably atrial fibrillation. This approach yielded improved effectiveness when it was used by veterinarians with cardiology experience. Thus, introducing hands-on training courses, particularly those focused on cardiology and interactive workshops, may enable frontline veterinarians to promptly identify arrhythmias using PWA, facilitating timely ECG examinations or referrals.
Topics: Animals; Cross-Sectional Studies; Electrocardiography; Dogs; Cats; Dog Diseases; Pulse Wave Analysis; Arrhythmias, Cardiac; Cat Diseases; Blood Pressure Determination; Humans; Female; Blood Pressure; Male
PubMed: 38422616
DOI: 10.2460/ajvr.23.10.0233 -
Scientific Reports Feb 2024Airborne transmission of pathogens plays a major role in the spread of infectious diseases. Aerosol particle production from the lung is thought to occur in the...
Airborne transmission of pathogens plays a major role in the spread of infectious diseases. Aerosol particle production from the lung is thought to occur in the peripheral airways. In the present study we investigated eighty lung-healthy subjects of two age groups (20-39, 60-76 years) at rest and during exercise whether lung function parameters indicative of peripheral airway function were correlated with individual differences in aerosol particle emission. Lung function comprised spirometry and impulse oscillometry during quiet breathing and an expiratory vital capacity manoeuvre, using resistance (R5) and reactance at 5 Hz (X5) as indicators potentially related to peripheral airway function. The association between emission at different ventilation rates relative to maximum ventilation and lung function was assessed by regression analysis. In multiple regression analyses including age group, only vital capacity manoeuvre R5 at 15% to 50% of end-expiratory vital capacity as well as quiet breathing X5 were independently linked to particle emission at 20% to 50% of maximum ventilation, in addition to age group. The fact that age as predictive factor was still significant, although to a lower degree, points towards further effects of age, potentially involving surface properties not accounted for by impulse oscillometry parameters.
Topics: Humans; Young Adult; Adult; Airway Resistance; Oscillometry; Lung; Respiratory Function Tests; Spirometry; Forced Expiratory Volume
PubMed: 38409397
DOI: 10.1038/s41598-024-55117-2 -
Respiratory Research Feb 2024Intra-breath oscillometry has been proposed as a sensitive means of detecting airway obstruction in young children. We aimed to assess the impact of early life wheezing...
BACKGROUND
Intra-breath oscillometry has been proposed as a sensitive means of detecting airway obstruction in young children. We aimed to assess the impact of early life wheezing and lower respiratory tract illness on lung function, using both standard and intra-breath oscillometry in 3 year old children.
METHODS
History of doctor-diagnosed asthma, wheezing, bronchiolitis and bronchitis and hospitalisation for respiratory problems were assessed by questionnaires in 384 population-based children. Association of respiratory history with standard and intra-breath oscillometry parameters, including resistance at 7 Hz (R), frequency-dependence of resistance (R), reactance at 7 Hz (X), area of the reactance curve (AX), end-inspiratory and end-expiratory R (R, R) and X (X, X), and volume-dependence of resistance (ΔR = R-R) was estimated by linear regression adjusted on confounders.
RESULTS
Among the 320 children who accepted the oscillometry test, 281 (88%) performed 3 technically acceptable and reproducible standard oscillometry measurements and 251 children also performed one intra-breath oscillometry measurement. Asthma was associated with higher R, R, ΔR and R and wheezing was associated with higher ΔR. Bronchiolitis was associated with higher R and AX and lower X and bronchitis with higher R. No statistically significant association was observed for hospitalisation.
CONCLUSIONS
Our findings confirm the good success rate of oscillometry in 3-year-old children and indicate an association between a history of early-life wheezing and lower respiratory tract illness and lower lung function as assessed by both standard and intra-breath oscillometry. Our study supports the relevance of using intra-breath oscillometry parameters as sensitive outcome measures in preschool children in epidemiological cohorts.
Topics: Humans; Child, Preschool; Respiratory Sounds; Spirometry; Respiratory System; Asthma; Respiratory Mechanics; Bronchiolitis; Bronchitis
PubMed: 38402379
DOI: 10.1186/s12931-024-02701-9 -
Academic Radiology Feb 2024Emergent evidence in several respiratory diseases supports translational potential for Phase-Resolved Functional Lung (PREFUL) MRI to spatially quantify ventilation but...
RATIONALE AND OBJECTIVES
Emergent evidence in several respiratory diseases supports translational potential for Phase-Resolved Functional Lung (PREFUL) MRI to spatially quantify ventilation but its feasibility and physiological relevance have not been demonstrated in patients with asthma. This study compares PREFUL-derived ventilation defect percent (VDP) in severe asthma patients to healthy controls and measures its responsiveness to bronchodilator therapy and relation to established measures of airways disease.
MATERIALS AND METHODS
Forty-one adults with severe asthma and seven healthy controls performed same-day free-breathing H MRI, Xe MRI, spirometry, and oscillometry. A subset of participants (n = 23) performed chest CT and another subset of participants with asthma (n = 19) repeated H MRI following the administration of a bronchodilator. VDP was calculated for both PREFUL and Xe MRI. Additionally, the percent of functional small airways disease was determined from CT parametric response maps (PRM).
RESULTS
PREFUL VDP measured pre-bronchodilator (19.1% [7.4-43.3], p = 0.0002) and post-bronchodilator (16.9% [6.1-38.4], p = 0.0007) were significantly greater than that of healthy controls (7.5% [3.7-15.5]) and was significantly decreased post-bronchodilator (from 21.9% [10.1-36.9] to 16.9% [6.1-38.4], p = 0.0053). PREFUL VDP was correlated with spirometry (FEV%: r = -0.46, p = 0.0023; FVC%: r = -0.35, p = 0.024, FEV/FVC: r = -0.46, p = 0.0028), Xe MRI VDP (r = 0.39, p = 0.013), and metrics of small airway disease (CT PRM: r = 0.55, p = 0.021; Xrs: r = -0.44, p = 0.0046, and AX: r = 0.32, p = 0.044).
CONCLUSION
PREFUL-derived VDP is responsive to bronchodilator therapy in asthma and is associated with measures of airflow obstruction and small airway dysfunction. These findings validate PREFUL VDP as a physiologically relevant and accessible ventilation imaging outcome measure in asthma.
PubMed: 38378325
DOI: 10.1016/j.acra.2024.01.039 -
American Journal of Respiratory and... May 2024
Topics: Humans; Oscillometry; Sleep Apnea, Obstructive
PubMed: 38364256
DOI: 10.1164/rccm.202312-2316LE -
American Journal of Respiratory and... May 2024
Topics: Humans; Oscillometry
PubMed: 38364253
DOI: 10.1164/rccm.202312-2222LE