Effects of the intermittent intrapulmonary deflation technique on expiratory flow limitation: an in vitro study.

INTRODUCTION: The intermittent intrapulmonary deflation (IID) technique is a recent airway clearance technique that intends to delay the onset of expiratory flow limitation (EFL) during exhalation. We showed in a previous study that IID increased the expiratory volume of COPD patients compared to quiet breathing and positive expiratory pressure (PEP) therapy. We hypothesized that it was due to the attenuation of the EFL. OBJECTIVES: To verify the physiologic effects of IID and PEP techniques on EFL with a mechanical lung model. METHODS: A mechanical lung model was created to assess the effects of IID and PEP techniques. The thorax was simulated by a plexiglas box in which an adult test lung was connected. A calibration syringe simulated the inspiratory phase. Later, with activation of the IID, the expiratory phase was driven by the deflation generated by the device. With PEP, the expiration occurred maintaining an expiratory pressure between 5 and 10 cmH2O. A pneumotachograph and a pressure transducer were placed in series for flow, volumes and pressure measurements. RESULTS: The model reproduced physiological characteristics of EFL. However, the deflation of the model was slowed by IID and PEP, and flow remained almost constant, so flow limitation was reduced. CONCLUSION: The IID and PEP attenuate EFL and increase exhaled volume in the in vitro model.

Systems on Top of Nasal Cannula Improve Oxygen Delivery in Patients with COVID-19: a Randomized Controlled Trial.

BACKGROUND: Treating hypoxemia while meeting the soaring demands of oxygen can be a challenge during the COVID-19 pandemic. OBJECTIVE: To determine the efficacy of the surgical facemask and the double-trunk mask on top of the low-flow oxygen nasal cannula on arterial partial pressure of oxygen (PaO2) in hypoxemic COVID-19 patients. DESIGN: Randomized controlled trial. PARTICIPANTS: Hospitalized adults with COVID-19 and hypoxemia treated with the low-flow nasal cannula were enrolled between November 13, 2020, and March 05, 2021. INTERVENTIONS: Patients were randomized in a 1:1:1 ratio to receive either the nasal cannula alone (control) or the nasal cannula covered by the surgical facemask or the double-trunk mask. Arterial blood gases were collected at baseline and 30 min after the use of each system. The oxygen output was adapted afterwards to retrieve the baseline pulse oxygen saturation. The final oxygen output value was recorded after another 30-min period. MAIN MEASURES: The primary outcome was the absolute change in PaO2. Secondary outcomes included changes in oxygen output, arterial partial pressure of carbon dioxide (PaCO2), vital parameters, and breathlessness. KEY RESULTS: Arterial blood samples were successfully collected in 24/27 (8 per group) randomized patients. Compared to the nasal cannula alone, PaO2 increased with the surgical facemask (mean change: 20 mmHg, 95% CI: 0.7-38.8; P = .04) and with the double-trunk mask (mean change: 40 mmHg; 95% CI: 21-59; P < .001). Oxygen output was reduced when adding the surgical facemask (median reduction: 1.5 L/min [95% CI: 0.5-4.5], P < .001) or the double-trunk mask (median reduction: 3.3 L/min [95% CI: 2-5], P < .001). The double-trunk mask was associated with a PaCO2 increase of 2.4 mmHg ([95% CI: 0-4.7], P = .049). Neither mask influenced vital parameters or breathlessness. CONCLUSIONS: The addition of the surgical facemask or the double-trunk mask above the nasal cannula improves arterial oxygenation and reduces oxygen consumption.

European Survey: Dysphagia Management in Patients with Neuromuscular Diseases.

Dysphagia is common in patients with neuromuscular diseases (NMDs). Its management differs by country and clinical setting. The purpose of this study was to describe current practices in the management of dysphagia in NMDs across Europe. An online survey of sixteen questions was developed, including basic information on facilities, existence of a management protocol, availability of dedicated therapists, tools used during screening, assessment, treatment stages, and treatment strategies. The survey was rolled out to European healthcare facilities providing care for NMDs. A total of 140 facilities across 25 European countries completed the survey. Substantial discrepancies in dysphagia management were identified among respondents. Seventy-two percent of the facilities reported having a protocol for at least one of the three management stages whereas only 39% had one for all. Speech and language therapists were reported as involved throughout the entire management stage while participation of other members from multidisciplinary teams varied depending on the stage. Clinical swallowing assessment was the most frequently reported tool in the assessment and treatment stages. For screening, questionnaires were the most frequently used while instrumental examinations were mainly reported in the assessment stage. For the treatment stage, adaptation strategies (diet, food, and posture) were the most reported approaches. In conclusion, the survey highlighted the absence of a defined protocol concerning the management of dysphagia in most of the surveyed healthcare facilities. Standardized training strategies and guidelines are necessary in the future to familiarize clinicians with each stage of the management of dysphagia.

The effect of tongue elevation muscle training in patients with obstructive sleep apnea: A randomised controlled trial.

BACKGROUND: Oropharyngeal myofunctional therapy is a multi-component therapy effective to reduce the severity of obstructive sleep apnoea (OSA). However, existing protocols are difficult to replicate in the clinical setting. There is a need to isolate the specific effectiveness of each component of the therapy. OBJECTIVE: To assess the effects of a 6 weeks tongue elevation training programme in patients with OSA. METHODS: We conducted a multicentre randomised controlled trial. Eligible participants were adults diagnosed with moderate OSA who presented low adherence to continuous positive airway pressure therapy (mean use <4 h per night). The intervention group completed a 6 weeks tongue elevation training protocol that consisted in anterior tongue elevation strength and endurance tasks with the Iowa Oral Performance Instrument. The control group completed a 6 weeks sham training protocol that involved expiratory muscle training at very low intensity. Polygraphy data, tongue force and endurance, and OSA symptoms were evaluated pre- and post-intervention. The primary outcome was apneoa-hypopnea index (AHI). RESULTS: Twenty-seven patients (55 ± 11 years) were recruited. According to modified intention-to-treat analysis (n = 25), changes in AHI and c did not significantly differ between groups. Daytime sleepiness (Epworth Sleepiness Scale) and tongue endurance significantly improved in the intervention group compared to the control group (p = .015 and .022, respectively). In the intervention group, 75% of participants had a decrease in daytime sleepiness that exceeded the minimal clinically important difference. CONCLUSION: Six weeks of tongue elevation muscle training had no effect on OSA severity.

Screening for oropharyngeal dysphagia in adult patients with neuromuscular diseases using the Sydney Swallow Questionnaire.

INTRODUCTION/AIMS: Oropharyngeal dysphagia is common in patients with neuromuscular diseases (NMDs). Its early recognition is vital for proper management. We tested a large cohort of adult NMD patients for oropharyngeal dysphagia using the Sydney Swallow Questionnaire (SSQ). We also looked for possible differences in characteristics of oropharyngeal dysphagia in various NMD groups and diseases. Finally, we compared results of this screening with those from their corresponding medical records for eventual "clinical history" of dysphagia. METHODS: We asked patients to fill in the SSQ during follow-up outpatient visits at our neuromuscular reference center. A total score above the cutoff score of 118.5 out of 1700 was indicative of oropharyngeal dysphagia. RESULTS: Of the 304 adult patients assessed for eligibility, 201 NMD patients (96 women and 105 men, aged 49.0 ± 16.2 years) were included and tested in this study. Oropharyngeal dysphagia was detected in 45% of all the NMD patients when using the SSQ, whereas only 12% had a positive medical record for dysphagia. The median SSQ scores for patients with myotonic syndromes (including myotonic dystrophy type 1), with amyotrophic lateral sclerosis, and with facioscapulohumeral dystrophy were above the cutoff score. The SSQ scores obtained revealed distinct oropharyngeal dysphagia characteristics in the different NMD groups and diseases. DISCUSSION: The SSQ tests positively for oropharyngeal dysphagia in a higher proportion of NMD patients compared with their medical records. The distinct oropharyngeal dysphagia characteristics we revealed in different NMD groups and diseases may help to elaborate adapted clinical approaches in the management of oropharyngeal dysphagia.

Artificial intelligence outperforms pulmonologists in the interpretation of pulmonary function tests.

The interpretation of pulmonary function tests (PFTs) to diagnose respiratory diseases is built on expert opinion that relies on the recognition of patterns and the clinical context for detection of specific diseases. In this study, we aimed to explore the accuracy and interrater variability of pulmonologists when interpreting PFTs compared with artificial intelligence (AI)-based software that was developed and validated in more than 1500 historical patient cases.120 pulmonologists from 16 European hospitals evaluated 50 cases with PFT and clinical information, resulting in 6000 independent interpretations. The AI software examined the same data. American Thoracic Society/European Respiratory Society guidelines were used as the gold standard for PFT pattern interpretation. The gold standard for diagnosis was derived from clinical history, PFT and all additional tests.The pattern recognition of PFTs by pulmonologists (senior 73%, junior 27%) matched the guidelines in 74.4±5.9% of the cases (range 56-88%). The interrater variability of κ=0.67 pointed to a common agreement. Pulmonologists made correct diagnoses in 44.6±8.7% of the cases (range 24-62%) with a large interrater variability (κ=0.35). The AI-based software perfectly matched the PFT pattern interpretations (100%) and assigned a correct diagnosis in 82% of all cases (p<0.0001 for both measures).The interpretation of PFTs by pulmonologists leads to marked variations and errors. AI-based software provides more accurate interpretations and may serve as a powerful decision support tool to improve clinical practice.

Inspiratory muscle strength training improves lung function in patients with the hypermobile Ehlers-Danlos syndrome: A randomized controlled trial.

As exertional inspiratory dyspnea is a common disabling complaint in hypermobile Ehlers-Danlos syndrome (hEDS) often also known as joint hypermobility syndrome (JHS), we investigated inspiratory muscle (IM) strength in patients with hEDS, and we assessed the effects of IM training (IMT) on IM strength, lung function, and exercise capacity. A prospective evaluation of IM strength followed by a randomized controlled trial of IMT was performed in women with hEDS. Sniff nasal inspiratory pressure (SNIP) was used to routinely measure IM strength and IMT was carried out using a pressure threshold device. IM strength (main outcome), cardiopulmonary function, exercise capacity, and emotional distress of both the treated and control groups were evaluated at the start and at the end of the 6-week training period. IM strength was reduced (<80% of predicted) in 77% of patients (80/104). Lung function was normal, although 24% of patients had a higher forced expiratory vital capacity (FVC) than normal and 12% of patients had a higher total lung capacity (TLC) than normal. Both the IMT and control groups (n = 20) had similar baseline characteristics. Significant changes were noted only in the IMT group after IMT. At the end of the program, IMT improved SNIP (20%) (before: 41 ± 17 cm H2 O [28, 53] vs. after: 49 ± 18 cm H2 O [34;65]), six-minute walking distance (6MWD) (60 m) (455 ± 107 m [379,532] vs. 515 ± 127 m [408, 621]), and forced expiratory volume in one second (FEV1) (285 mL) (94 ± 14% pred [84,104] vs. 103 ± 11% pred [94, 112]). IM strength is significantly reduced in patients with hEDS. IMT improved IM strength, lung function, and exercise capacity. Our findings suggest that IMT should be added to usual care.

Validation and Reliability of the French Version of the Sydney Swallow Questionnaire.

Oropharyngeal dysphagia is frequently under-reported and early detection may lead to adapt strategies of rehabilitation and management decisions. The Sydney Swallow Questionnaire (SSQ), a self-reported questionnaire for the detection and quantification of oropharyngeal dysphagia, was previously adapted and validated in other languages but not in French. The purposes of this study were to develop and validate a French version of SSQ (SSQ-f) and to assess its psychometric properties. This SSQ-f, obtained by back-translation and cross-cultural adaptation, was validated in 27 patients with impaired swallowing and 27 healthy controls. After inclusion, patients filled in the SSQ-f and performed a videofluoroscopic swallow study. The penetration aspiration scale (PAS) and Dysphagia outcome and severity scale (DOSS) were assigned to assess construct validity. Sensitivity and specificity of cut-off scores for the SSQ-f were assessed by the receiver operating characteristic (ROC) curves. Moreover, the SSQ-f was repeated after 2 weeks to evaluate its test-retest reliability. The results supported that SSQ-f was considered understandable. Its total score was strongly correlated to the DOSS (r = - 0.873) and to the PAS (r = 0.738). It demonstrated acceptable internal consistency, with Cronbach's alpha values ranging from 0.744 to 0.956. The test-retest reliability was excellent. According to the ROC curve, cut-off scores of 118.5 or 218.5 were proposed for determining oropharyngeal dysphagia using DOSS as a reference and 755.0, using PAS as reference. No ceiling or floor effects were observed. In conclusion, the SSQ-f is a valid and reliable instrument to measure and detect oropharyngeal dysphagia in French-speaking subjects and can be used in a clinical setting.

Sleep-disordered breathing in patients with neuromuscular disease.

Sleep-disordered breathing (SDB) is relatively common in general population as well as in patients with neuromuscular disease. SDB comprises a wide spectrum of disorders varying from simple snoring to complete closure of the upper airway as seen in obstructive sleep apnoea (OSA). It includes also other disorders like prolonged hypoxemia, hypoventilation, and central sleep apnoea (CSA). Neuromuscular diseases (NMD) form a group of disorders that can cause significant reduction in the quality and span of life. The involvement of respiratory system in the context of these disorders is the most serious complication, and it is considered as the leading cause of death in those patients. NMD can affect ventilation, cough, swallowing, and phonation. The involvement of respiratory muscles makes NMD patients vulnerable to sleep-disordered breathing with a significant prevalence of SDB among such patients.

Reliability and Reproducibility of Chest Wall Expansion Measurement in Young Healthy Adults.

OBJECTIVE: The purposes of this study were to (1) evaluate the reliability and reproducibility of chest expansion (CE) measurement on 2 different levels and (2) observe relationships between upper and lower CE measurements and lung function. METHODS: Fifty-three healthy subjects aged between 18 and 39 years were recruited. Chest expansion measurements were taken with a cloth tape measure at 2 levels of the rib cage (upper and lower). Reproducibility of the measurement was measured for 2 physiotherapists and on 2 different days. Lung function (ie, forced expiratory volume in 1 second [FEV1], forced vital capacity (FVC), vital capacity and, inspiratory capacity) was measured for all subjects by a spirometer (MEC Pocket-spiro USB100, Medical Electronic Construction, Brussels, Belgium). RESULTS: Upper CE was less than lower CE (5.4 cm and 6.4 cm, respectively; P < .001). Intrarater and interrater reliability were good for upper and lower CE. Reproducibility between physiotherapists was verified for both CE measurements. Reproducibility between days was only verified for upper CE. Sex influenced lower CE. Upper and lower CE values were correlated (r = 0.747; P < .01). Lower and upper CE were significantly and positively correlated with all lung function parameters and inspiratory muscle strength (moderately and weakly, respectively) except to inspiratory capacity for upper CE (P = .051) and for FEV1/FVC for both CE measurements. CONCLUSION: Upper and lower CE measurements showed good intra- and interrater reliability and reproducibility in healthy subjects. Although both measurements were correlated with lung functions (ie, FEV1, FVC, and vital capacity), the findings of this study showed that upper CE measurements may be more useful in clinical practice to evaluate chest mobility and to give indirect information on lung volume function and inspiratory muscle strength.

Validation of the French version of the Leicester Cough Questionnaire in chronic obstructive pulmonary disease.

Cough is one of the three major symptoms reported by chronic obstructive pulmonary disease (COPD) patients. The Leicester Cough Questionnaire (LCQ) is a questionnaire exploring the impact of cough, but it does not exist in French. The aim of this study was to develop a French version of LCQ and to assess its psychometrics properties. A forward-backward translation process was used to develop the French version of the LCQ. COPD patients completed LCQ and Cough and Sputum Assessment Questionnaire (CASA-Q) to determine concurrent validity, content validity and internal consistency. Two weeks later, the LCQ was repeated to evaluate the reproducibility. Seventy-four COPD patients were recruited. The concurrent validity showed highly significant correlations between all scores of LCQ and CASA-Q (p < 0.001). The content validity was good with domain total scores correlations ranging from 0.918 to 0.953. The LCQ domains and total scores showed a very good internal consistency with Cronbach's α coefficients ranging between 0.802 and 0.917. The test-retest reliability was high in COPD patients with no change in cough. In conclusion, The French version of the LCQ is a valid and reliable instrument to measure health status in COPD patients.

Short-Term Effect of Intermittent Intrapulmonary Deflation on Air Trapping in Patients With COPD.

BACKGROUND: Intermittent intrapulmonary deflation is an airway clearance technique that generates negative pressure during expiratory phases. This technology is intended to reduce air trapping by delaying the onset of air-flow limitation during exhalation. The objective of this study was to compare the short-term effect of intermittent intrapulmonary deflation versus positive expiratory pressure (PEP) therapy on trapped gas volume and vital capacity (VC) in patients with COPD. METHODS: We designed a randomized crossover study in which the participants with COPD received a 20-min session of both intermittent intrapulmonary deflation and PEP therapy on separate days and in random order. Lung volumes were measured via body plethysmography and helium dilution techniques, and spirometric outcomes were reviewed before and after each therapy. The trapped gas volume was estimated via functional residual capacity (FRC), residual volume (RV), and by the difference between FRC obtained through body plethysmography and helium dilution. Each participant also performed 3 VC maneuvers, from total lung capacity to RV with both devices. RESULTS: Twenty participants with COPD (mean ± SD ages 67 ± 8 y; FEV1 48.1 ± 17.0%) were recruited. There was no difference between the devices in FRC or trapped gas volume. However, the RV decreased more during intermittent intrapulmonary deflation compared with PEP. The intermittent intrapulmonary deflation mobilized a larger expiratory volume than PEP during the VC maneuver (mean difference 389 mL, 95% CI 128-650 mL; P = .003). CONCLUSIONS: The RV decreased after intermittent intrapulmonary deflation compared with PEP, but this effect was not captured by other estimates of hyperinflation. Although the expiratory volume obtained during the VC maneuver with intermittent intrapulmonary deflation was greater than that obtained with PEP, the clinical importance as well as the long-term effects remain to be determined.(ClinicalTrials.gov registration NCT04157972.).

Differential diagnosis in a primary care population with presumed airway obstruction: a real-life study.

BACKGROUND: Asthma and chronic obstructive pulmonary disease (COPD) have major symptoms in common. However, the mode of the underlying chronic airway inflammation is different. There is still no single diagnostic test that can be considered a gold standard to distinguish asthma from COPD. OBJECTIVES: To determine the diagnostic accuracy for asthma and COPD of a series of diagnostic steps in a population older than 40 years with probable obstructive airway disease (OAD) in primary care. METHODS: In this prospective cohort study, patients without a certain diagnosis underwent a work-up, including office spirometry by their general practitioner (GP). They were then referred to a pulmonologist, and they had control visits with their GP. The diagnostic gain of subsequent steps was calculated for 2 endpoints, namely the specialist's opinion and the GP's final opinion. RESULTS: Up to 60% of the patients failed to consult with the pulmonologist. For this subgroup, the office spirometry induced significantly more diagnostic congruency than any other diagnostic step. The specialists rejected 44.5% of the diagnoses made by the GPs, including spirometry. High values of diagnostic gain were found after the office spirometry and after the specialist's advice. Up to 25% of the population taking bronchodilators were judged not to suffer from OAD. CONCLUSIONS: Office spirometry added significantly more to the diagnostic certainty of the GPs than questionnaires, history and clinical examination. A pulmonologist's advice contributed more to diagnostic certainty than any other diagnostic step. Nevertheless, 26% of the diagnoses made by the chest physicians were reconsidered by the GPs.

Technical assessment of spirometers connected in series.

BACKGROUND: Office spirometers are now widely used to detect obstructive lung diseases. To test the technical characteristics of these devices, simulation of different forced expiratory maneuvers is performed, using computer generated waveforms. However, the tests with human subjects are also useful to detect technical flaws. The procedure used by some authors to test the accuracy of office spirometers is to compare measurements made by 2 spirometers connected in series. OBJECTIVE: The aim of this study was to evaluate the accuracy of this latter procedure. METHODS: Two sets of 2 spirometers connected in series were used: the PocketSpiro with the MicroLoop, and the PocketSpiro with the SpiroScout. Different standard American Thoracic Society curves were selected for both ambient temperature and pressure (ATP) and body temperature and pressure saturated (BTPS) conditions and generated with a waveform simulator. We compared lung function indices (FVC, peak expiratory flow, and FEV(1)) recorded by the PocketSpiro when it was placed respectively upstream or downstream in the assembly. RESULTS: In ATP conditions, lung function indices were generally higher when the spirometer was placed downstream rather than upstream. The observed deviations reached up to 10%. In BTPS conditions, lung function indices were underestimated when the spirometer was placed downstream, as compared to the ATP procedure. The modification of the flow characteristics and the temperature drop are the 2 mechanisms that could explain our results. CONCLUSIONS: Connecting the spirometers in series gives variable results, depending on the position of the spirometer in the assembly. Individual tests are therefore essential, as results are not interchangeable.

An increase in endogenous erythropoietin concentrations has no cardioprotective effects in patients undergoing coronary artery bypass graft surgery.

OBJECTIVE: Preliminary data showed an increase in endogenous erythropoietin (EPO) concentrations after acute normovolemic hemodilution (ANH) in patients undergoing coronary artery bypass graft (CABG) surgery. Numerous studies have shown the organ protective properties of EPO. The aim of this study was to investigate the cardioprotective effects of these increased EPO concentrations that resulted from ANH during cardiac surgery. DESIGN: A prospective, randomized, blind study. SETTING: A university hospital. PARTICIPANTS: A total of 93 patients undergoing isolated CABG surgery with or without cardiopulmonary bypass (CPB). INTERVENTIONS: Subjects with CPB were randomized into the control (C) or ANH group. Those in the off-pump coronary artery bypass group underwent no treatment. In the ANH group, a precalculated amount of blood was withdrawn and replaced by colloids after the induction of anesthesia. MEASUREMENTS AND MAIN RESULTS: Hemodynamic parameters were recorded intra- and postoperatively. Troponin concentrations were measured as a routine parameter postoperatively. Upon intensive care unit arrival, the EPO levels were higher in the ANH group than in the C group. There was no significant difference between the troponin values of the C and the ANH groups at 4 hours postoperatively. CONCLUSIONS: In patients undergoing CABG surgery on CPB, an increase in endogenous EPO concentrations in the physiologic range has no cardioprotective effects.

Telerehabilitation as a Form of Pulmonary Rehabilitation in Chronic Lung Disease: A Systematic Review.

INTRODUCTION: Tele-rehabilitation is increasingly used to deliver pulmonary rehabilitation. The aim of this systematic review was to compare the effect between tele-pulmonary rehabilitation and classical supervised pulmonary rehabilitation. METHOD: Three databases were analysed (PubMed, PEDro, Scopus). The selection and evaluation of studies followed the PRISMA guidelines. The risk of bias was evaluated using the PEDro Scale. RESULTS: From the initial selection (n = 245), ten studies were retrieved, including from 10 to 67 patients. All but two (IPF) included patients with COPD. Based on the FEV1, patients with COPD were mainly categorised as moderate and severe. The teleactivities were heterogenous in terms of proposed exercises and way of settings and often not in agreement with the guidelines about pulmonary rehabilitation. Despite this, the effects of the interventions were globally positive on functional exercise capacity, quality of life, anxiety and depression, and impact of COPD on personal life but not on dyspnoea. The PEDro scores varied from 4 to 8. The adherence was higher than 80% when supervision during the exercise was included. CONCLUSION: This review demonstrated that the telerehabilitation is safe and well accepted by the patients, and could be considered as one option of classical pulmonary rehabilitation to improve the functional exercise capacity, quality of life, anxiety and depression, and the impact of COPD on personal's life. This conclusion cannot be extrapolated to the other chronic lung diseases due to the lack of data.

Effect of N-acetyl-cysteine and hyperoxia on erythropoietin production.

Previous studies in healthy subjects have shown an increase in erythropoietin (EPO) production after administration of N-acetyl-cysteine (NAC). These authors hypothesized that NAC increases intracellular reduced glutathione, decreasing reactive oxygen species and enabling EPO production. We investigated if EPO production could be stimulated with a single dose of NAC, after 90 min of pure oxygen breathing. Thirty-eight healthy volunteers were randomized into either the control (C) group or the NAC group, which received 600 mg NAC PO dissolved in a glass of orange juice, 60 min before breathing 15 L/min of 100% normobaric oxygen. Orange juice was administered to both groups. Blood samples for EPO measurement were taken at T0, before the orange juice administration, and T1, T2, T3 and T4, respectively, 8, 24, 32 and 48 h after the orange juice. The EPO concentrations of the NAC group decreased significantly at T1, followed by a significant increase compared to baseline, which was obvious until T4. The EPO concentrations of the C group did not show any significant variations. In this study, a significant increase of EPO production was observed after a short-term hyperoxic stimulus only when preceded with the administration of a single dose of NAC.

Chest Expansion and Lung Function for Healthy Subjects and Individuals With Pulmonary Disease.

BACKGROUND: The purposes of this study were to verify the correlation between chest expansion and lung function within a larger sample of subjects composed of both healthy subjects and subjects affected by pulmonary disease, and to verify the influence of age, body mass index, and gender on chest expansion. METHODS: Adults were recruited prospectively when they visited the lung function lab. Chest expansion was measured with a measuring tape at 2 different levels of the rib cage by 1 blinded examiner. Spirometry was performed for each subject. RESULTS: Data from 251 subjects between 18 and 88 y old were collected and analyzed. Among the analyzed subjects, mean upper and lower chest expansion were 4.82 ± 1.84 cm and 3.99 ± 2.15 cm, respectively. A significant but poor correlation was found between both chest expansion and all lung function parameters (total lung capacity, FVC, and FEV1) (P = .01). Negative significant correlations were found between chest expansion and age as well as body mass index. The difference in upper chest expansion between obese and nonobese subjects was not statistically significant, but the difference in lower chest expansion was significant for these 2 groups. Finally, upper and lower chest expansion were not different between males and females. CONCLUSIONS: Based on these results, one cannot validate the use of chest expansion measurement to define lung function. In centers that have easy access to more precise and complete methods to measure lung function, the measurement of chest expansion for diagnostic purposes seems to be archaic. Additionally, age and body mass index are 2 parameters that can influence chest expansion.