Recommendations for a Standardized Pulmonary Function Report. An Official American Thoracic Society Technical Statement

Tolerability and efficacy of switching anti-fibrotic treatment from nintedanib to pirfenidone for idiopathic pulmonary fibrosis

BACKGROUND

In real-world studies, the rate of discontinuation of nintedanib (NT) varies from 4% to 53%. Switching anti-fibrotic treatment in patients with idiopathic pulmonary fibrosis (IPF) has not been adequately investigated, and data on the tolerability and efficacy of changes in anti-fibrotic treatment is limited in clinical practice.

OBJECTIVE

To identify factors associated with poor continuation of NT, efficacy and predictors of deterioration after switching from NT to pirfenidone (PFD) in patients with IPF.

SUBJECTS AND METHODS

One hundred and seventy patients with IPF in whom NT was introduced between April 2017 and March 2022 were included to investigate NT continuation status and the effect of switching to PFD.

RESULTS

A total of 123 patients (72.4%) continued NT for 1 year and had a significantly higher %forced vital capacity (FVC) at NT introduction than those who discontinued within 1 year (80.9% ± 16.3% vs. 71.9% ± 22.1%, P = 0.004). The determinant of poor NT continuation was the high GAP stage. On the other hand, 28 of 36 patients who discontinued NT because of disease progression switched to PFD. Consequently, FVC decline was suppressed before and after the change. The predictor of deterioration after the switch was a lower body mass index.

CONCLUSIONS

In patients with IPF, early NT introduction increased continuation rates, and switching to PFD was effective when patients deteriorated despite initial NT treatment.

Functional trajectories before and after loss of ambulation in Duchenne muscular dystrophy and implications for clinical trials

This study examined functional trajectories of subjects during the transition phase between ambulatory and non-ambulatory Duchenne muscular dystrophy (DMD) to inform clinical trial designs for new therapeutics. Ambulatory, pulmonary, and upper limb function leading up to loss of ambulation (LoA) and non-ambulatory measures following LoA were quantified; time ordering of pulmonary and upper limb milestones relative to LoA were determined; and the 10-second time threshold for 10-meter walk/run (10MWR) as a marker of approaching LOA was explored. Included in this analysis were 51 subjects aged between 7 and 18 years who experienced LoA during follow-up in the PRO-DMD-01 natural history study. Mean age at LoA was 12.7 (7.1-18.6) years. Mean annual rates of decline in forced vital capacity (FVC) <80%-predicted and performance of upper limb (PUL) 1.2 total score were smaller before than after LoA, but not significantly (FVC %-predicted: 5.6% vs. 10.1%, p = 0.21; PUL 1.2 total score: 2.3 vs. 3.8 units, p = 0.20). More than half of patients experienced clinically significant deficits in FVC %-predicted and PUL 1.2 before experiencing LoA. Among subjects with baseline 10MWR >10 s, those with <1 year to LoA had similar mean ages but significantly worse mean ambulatory function at baseline compared to those with ≥1 year to LoA. Enriching DMD clinical trials for patients with declining pulmonary or upper limb function is achievable without restricting enrollment to non-ambulatory patients. The sequencing of LoA and initial deficits in pulmonary and upper limb function varied across patients and highlights the potential for composite outcomes or multi-outcome trial designs to assess disease-modifying therapies more comprehensively.

"Horses for courses" computed tomography or predicted total lung capacity for size matching in lung transplantation

Size-matching donors to recipients in lung transplantation continues to be a clinical challenge. Predicted total lung capacity equations, or more simply, donor and recipient heights, while widely used, are imprecise and may not be representative of the pool of donors and recipients. These inherent limitations may result in size discrepancies. The advent of easily accessible software and the widespread availability of computed tomography (CT) imaging in donor assessments have made it possible to directly measure lung volumes in donors and recipients. As a result, there is a growing interest in adopting personalized CT volumetry as an alternative. This article explores both methods and underscores the potential benefits and precision offered by CT.

Monitoring COPD patients: systemic and bronchial eosinophilic inflammation in a 2-year follow-up

BACKGROUND

High blood eosinophils seem to predict exacerbations and response to inhaled corticosteroids (ICS) treatment in patients with chronic obstructive pulmonary disease (COPD). The aim of our study was to prospectively evaluate for 2 years, blood and sputum eosinophils in COPD patients treated with bronchodilators only at recruitment.

METHODS

COPD patients in stable condition treated with bronchodilators only underwent monitoring of lung function, blood and sputum eosinophils, exacerbations and comorbidities every 6 months for 2 years. ICS was added during follow-up when symptoms worsened.

RESULTS

63 COPD patients were enrolled: 53 were followed for 1 year, 41 for 2 years, 10 dropped-out. After 2 years, ICS was added in 12/41 patients (29%) without any statistically significant difference at time points considered. Blood and sputum eosinophils did not change during follow-up. Only FEV1/FVC at T0 was predictive of ICS addition during the 2 year-follow-up (OR:0.91; 95% CI: 0.83-0.99, p = 0.03). ICS addition did not impact on delta (T24-T0) FEV1, blood and sputum eosinophils and exacerbations. After 2 years, patients who received ICS had higher blood eosinophils than those in bronchodilator therapy (p = 0.042). Patients with history of ischemic heart disease increased blood eosinophils after 2 years [p = 0.03 for both percentage and counts].

CONCLUSIONS

Blood and sputum eosinophils remained stable during the 2 year follow-up and were not associated with worsened symptoms or exacerbations. Almost 30% of mild/moderate COPD patients in bronchodilator therapy at enrollment, received ICS for worsened symptoms in a 2 year-follow-up and only FEV1/FVC at T0 seems to predict this addition. History of ischemic heart disease seems to be associated with a progressive increase of blood eosinophils.

Phase angle as an indicator of sarcopenia and malnutrition in patients with chronic obstructive pulmonary disease

BACKGROUND

Phase angle (PhA), which is measured using bioelectrical impedance analysis, is an indicator of muscle quality and malnutrition. PhA has been shown to be correlated with sarcopenia and malnutrition; however, studies on patients with chronic obstructive pulmonary disease (COPD) are limited. In this study, we investigated the correlation between PhA and sarcopenia and malnutrition and determined the cutoff values of PhA for those in patients with COPD.

METHODS

This study included 105 male patients with COPD (mean age 75.7 ± 7.7 years, mean forced expiratory volume in 1s % predicted [%FEV1] 57.0 ± 20.1%) and 12 male controls (mean age 74.1 ± 3.8 years) who were outpatients between December 2019 and March 2024. PhA was measured using the InBody S10, and its correlation with sarcopenia and malnutrition was assessed. The cutoff PhA values for sarcopenia and malnutrition were determined using receiver operating characteristic curves.

RESULTS

The prevalence rates of sarcopenia and malnutrition were 31% and 22%, respectively, in patients with COPD. PhA significantly correlated with sarcopenia- and malnutrition-related indicators. Multivariate logistic regression analysis independently correlated PhA with sarcopenia and malnutrition. The cutoff values of the PhA for sarcopenia and malnutrition were 4.75° (AUC = 0.78, 95% CI = 0.68-0.88) and 4.25° (AUC = 0.75, 95% CI = 0.63-0.86), respectively.

CONCLUSIONS

PhA was significantly correlated with sarcopenia and malnutrition in Japanese patients with COPD and may be a useful diagnostic indicator.

Lung function trajectories in a cohort of patients with moderate-to-severe asthma on mepolizumab, omalizumab, or dupilumab

BACKGROUND

Lung function is an independent predictor of mortality. We evaluated the lung function trajectories of a cohort of patients with asthma receiving biologic therapy.

METHODS

We identified 229 monoclonal antibody-naïve adult patients with moderate-to-severe asthma who initiated omalizumab, mepolizumab, or dupilumab between 2010 and 2022 in a large healthcare system in Boston, MA. Generalized additive mixed models were used to estimate the lung function trajectories during the 156 weeks following biologic initiation. Response was defined as an improvement in FEV1 or a decrease of ≤0.5% per year. The Kaplan-Meier estimator was used to assess time to no additional improvement in FEV1 in responders. All models were adjusted for age, sex, body mass index, smoking status, baseline exacerbation rate, and baseline blood eosinophil count.

RESULTS

Eighty-eight patients initiated mepolizumab, 76 omalizumab, and 65 dupilumab. Baseline eosinophil count was highest in the mepolizumab group (405 cells/mcL) and lowest for omalizumab (250 cells/mcL). Both FEV1 and FVC improved in the mepolizumab group (FEV1 + 20 mL/year; FVC +43 mL/year). For omalizumab, there was an initial improvement in the first year followed by decline with an overall FEV1 loss of -44 mL/year and FVC -32 mL/year. For dupilumab, both FEV1 (+61 mL/year) and FVC (+74 mL/year) improved over time. Fifty percent of the mepolizumab group, 58% omalizumab, and 72% of dupilumab were responders. The median time to no additional FEV1 improvement in responders was 24 weeks for omalizumab, 48 weeks for mepolizumab, and 57 weeks for dupilumab.

CONCLUSION

In this clinical cohort, mepolizumab, omalizumab, and dupilumab had beneficial effects on FEV1 and FVC with distinct post-initiation trajectories.

Longitudinal improvements in clinical and functional outcomes following initiation of elexacaftor/tezacaftor/ivacaftor in patients with cystic fibrosis

Background

Use of elexacaftor/tezacaftor/ivacaftor (ETI) for treatment of cystic fibrosis (CF) has resulted in unprecedented clinical improvements necessitating development of outcome measures for monitoring disease course. Intranasal micro-optical coherence tomography (μOCT) has previously helped detect and characterize mucociliary abnormalities in patients with CF. This study was done to determine if μOCT can define the effects of ETI on nasal mucociliary clearance and monitor changes conferred to understand mechanistic effects of CFTR modulators beyond CFTR activation.

Methods

26 subjects, with at least 1 F508del mutation were recruited and followed at baseline (visit 1), +1 month (visit 2) and +6 months (visit 4) following initiation of ETI therapy. Clinical outcomes were computed at visits 1, 2 and 4. Intranasal μOCT imaging and functional metrics analysis including mucociliary transport rate (MCT) estimation were done at visits 1 and 2.

Results

Percent predicted forced expiratory volume in 1 s (ppFEV1) showed a significant increase of +10.9 % at visit 2, which sustained at visit 4 (+10.6 %). Sweat chloride levels significantly decreased by -36.6 mmol/L and -41.3 mmol/L at visits 2 and 4, respectively. μOCT analysis revealed significant improvement in MCT rate (2.8 ± 1.5, visit 1 vs 4.0 ± 1.5 mm/min, visit 2; P = 0.048).

Conclusions

Treatment with ETI resulted in significant and sustained clinical improvements over 6 months. Functional improvements in MCT rate were evident within a month after initiation of ETI therapy indicating that μOCT imaging is sensitive to the treatment effect of HEMT and suggests improved mucociliary transport as a probable mechanism of action underlying the clinical benefits.

Functional analysis of airway remodeling is related with fibrotic mediators in asthmatic children

BACKGROUND

Asthmatic children present variable degrees of airway inflammation, remodeling, and resistance, which correlate with disease control and severity. The chronic inflammatory process of the airway triggers airway remodeling, which reflects the degree of airway resistance. Pro-inflammatory and pro-fibrotic mediators are centrally involved in this process.

OBJECTIVE

To investigate whether the levels of pulmonary and systemic pro-inflammatory and pro-fibrotic mediators present a correlation with the resistance of the respiratory system and of the proximal and distal airways.

METHODS

39 Asthmatic children (persistent mild and moderate) and 39 non-asthmatic children (both between 6 and 13 years old) were evaluated for anthropometric characteristics, lung function and mechanics, and pulmonary and systemic immune responses.

RESULTS

Asthmatic children showed an increased number of blood eosinophils (p < 0.04), basophils (p < 0.04), monocytes (p < 0.002) and lymphocytes (p < 0.03). In addition, asthmatic children showed impaired lung function, as demonstrated by FEV1 (p < 0.0005) and FEV1/FVC (p < 0.004), decreased total resistance of the respiratory system (R5Hz; p < 0.009), increased resistance of the proximal airways (R20Hz; p < 0.02), increased elastance (Z5Hz; p < 0.02) and increased reactance (X5Hz; p < 0.002) compared to non-asthmatic children. Moreover, the following inflammatory factors were significantly higher in asthmatic than non-asthmatic children: GM-CSF in the breath condensate (BC) (p < 0.0001) and in the serum (p < 0.0001); TGF-beta in the BC (p < 0.0001) and in the serum (p < 0.004); IL-5 in the BC (p < 0.02) and in the serum (p < 0.01); IL-4 in the serum (p < 0.0002).

CONCLUSIONS

Impulse oscillometry is a sensitive method to detect airway resistance in persistent mild and moderate asthmatic children, an event followed by increased levels of pro-inflammatory and pro-fibrotic mediators.

One-year follow-up of COVID-19 recoverees with impaired pulmonary function: A prospective cohort study

Decreased diffusion capacity for carbon monoxide (DLCO) is the most prevalent pulmonary testing abnormality among COVID-19 recoverees. We prospectively followed 51 individuals with impaired DLCO at an average of ∼3 months following COVID-19 and re-examined them at one year. At follow-up, mean DLCO increased from 68.0 % to 72.6 % (p = 0.002); while 33 % of the cohort experienced a clinically significant rise (>10 points) in DLCO, only 29 % normalized their values. While DLCO change did not correlate with symptoms, lack of improvement was more prevalent among individuals with obesity. Regardless of COVID-19 severity, a substantial proportion continued to exhibit DLCO impairment at 1-year.

Analysis of Endocrine and Inflammatory Markers in Preserved Ratio Impaired Spirometry

Chronic Obstructive Pulmonary Disease (COPD) is a disease of the lungs characterized by chronic airflow obstruction. Individuals with preserved ratio impaired spirometry (PRISm) may be at risk for developing COPD. This study aimed to characterize PRISm and COPD patients in terms of their immune response and endocrine profile to identify differences extending beyond lung function. The participants performed the clinical assessment, pulmonary function test, and blood collection to determine serum hormone levels and concentrations of cytokine. Differences were observed in the nutritional status, lung function, and comorbidity. There were no differences in IL-6, IL-8, IL-10, IL-12, and TNF levels between PRISm and COPD groups. Both PRISm and COPD patients have lower dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEA-S) levels than controls. Correlation analysis of PRISm and COPD patients revealed positive correlations between serum levels of DHEA-S and DHEA, with forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC), which negatively correlated with IL-8 levels. The results indicated that despite differences in lung function parameters, the PRISm and COPD groups exhibited similarities in endocrine profile alterations. This study represents the first attempt to link endocrine with immune markers and lung function in individuals with PRISm.

Long-Term Follow-up of Untreated Adult Patients with Spondylothoracic Dysostosis (Jarcho-Levin Syndrome)

BACKGROUND

Spondylothoracic dysostosis (STD), also known as Jarcho-Levin syndrome (JLS), is a rare autosomal recessive disorder affecting the formation of the spine, characterized by a complete bilateral fusion of the ribs at the costovertebral junction, producing a "crablike" appearance of the thorax. Despite being declared a core indication for a V-osteotomy vertical expandable prosthetic titanium rib (VEPTR) expansion thoracoplasty of the posterior thorax, the natural history of STD in untreated subjects remains poorly documented. In this study, we report radiographic and pulmonary function findings and Patient-Reported Outcomes Measurement Information System (PROMIS) and 24-Item Early Onset Scoliosis Questionnaire (EOSQ-24) scores for untreated adult subjects with STD to gain insights into the natural history.

METHODS

We identified 11 skeletally mature, untreated subjects with STD. Findings on medical evaluation, demographics, radiographic parameters, pulmonary function, genetic testing results, PROMIS measures, and EOSQ-24 scores were assessed.

RESULTS

Five male and 6 female subjects (mean age, 32.3 years [range, 15 to 70 years]) with a confirmed STD diagnosis based on radiographs and genetic testing were evaluated. Mean body mass index (BMI) was 24.4 kg/m 2 (range, 18 to 38.9 kg/m 2 ), and mean thoracic height was 16 cm (range, 12 to 17 cm). Pulmonary function tests (PFTs) showed a mean forced vital capacity (FVC) of 22% of predicted, mean forced expiratory volume in 1 second (FEV1) of 24% of predicted, and FEV1/FVC ratio of 107% of predicted. The mean PROMIS dyspnea score was 40 ± 8 points (range, 27.7 to 52.1 points). The mean total EOSQ-24 score was 77.3 ± 18 points (range, 43.9 to 93.2 points).

CONCLUSIONS

Our study characterizes the natural history of STD in untreated subjects. We confirmed the expected restrictive pattern in pulmonary function, but interestingly, our subjects exhibited better EOSQ scores compared with those reported in neuromuscular populations. PFT results and thoracic height did not correspond to PROMIS and EOSQ scores, questioning the use of those parameters as a surgical indication. We therefore suggest that the STD diagnosis as an absolute indication for VEPTR expansion thoracoplasty surgery be reconsidered.

LEVEL OF EVIDENCE

Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.

Reactance inversion in moderate to severe persistent asthma: low birth weight, prematurity effect, and bronchodilator response

INTRODUCTION

Reactance inversion (RI) has been associated with impaired peripheral airway function in persistent asthma. However, there is little to no data about the difference between asthmatic children with and without RI. This study aimed to detect clinical and lung function differences in moderate-severe asthmatic children with and without RI.

METHODS

This study was conducted between 2021 and 2022 in asthmatic school-age children. Impulse oscillometry (IOS) and spirometry were performed according to ATS/ERS standards.

RESULTS

A total of 62 patients, with a mean age of 8.4 years, 54.8% were males and were divided into three groups: group 1 (32.3%) with no RI, group 2 (27.4%) with RI but disappearing after bronchodilator test and group 3 (40.3%) with persistent RI after bronchodilator test. Children in groups 2 and 3 had significantly lower birth weights than in group 1. Group 2 had lower gestational age compared to group 1. FEV1 and FEF25-75 of forced vital capacity were significantly lower in groups 2 and 3. In group 3, R5, AX, R5-20, and R5-R20/R5 ratios were significantly higher. Bronchodilator responses (BDR) in X5c, AX, and R5-R20 were significantly different between groups and lower in group 3.

CONCLUSION

RI is frequently found in children with moderate-severe persistent asthma, particularly in those with a history of prematurity or low birth weight. In some patients, RI disappears after the bronchodilator test; however, it, persists in those with the worst pulmonary function. RI could be a small airway dysfunction marker.

Identification of clinical factors impacting outcome in patients undergoing autologous hematopoietic cell transplantation after BEAM and TEAM conditioning

Organ dysfunction, including pulmonary function impairment, plays a key role in the choice of conditioning chemotherapy before autologous hematopoietic stem cell transplantation (auto-HSCT). Replacement of BCNU/carmustine as part of BEAM (BCNU/carmustine, etoposide, cytarabine, and melphalan) conditioning protocol by thiotepa (TEAM) reduces pulmonary toxicity while maintaining efficacy. We retrospectively analyzed the association of clinical characteristics, comorbidities, and organ function with outcomes after conditioning with BEAM or TEAM. Three hundred ninety-six patients undergoing auto-HSCT (n = 333 with BEAM; n = 63 with TEAM) at our institution between 2008 and 2021 were included in this study. In the multivariate analysis, CO-diffusion capacity corrected for hemoglobin (DLCOcSB) ≤ 60% of predicted, progressive disease (PD) before auto-HSCT, Karnofsky performance score (KPS) ≤ 80%, HCT-CI score ≥ 4, and cardiac disease before auto-HSCT were associated with decreased overall survival (OS) in patients treated with BEAM. In contrast, only PD before auto-HSCT was identified in patients treated with TEAM. Patients conditioned with BEAM and DLCOcSB ≤ 60% had higher non-relapse mortality, including pulmonary cause of death. In summary, we have identified clinical and pulmonary risk factors associated with worse outcomes in patients conditioned with BEAM compared to TEAM. Our data suggest TEAM conditioning as a valid alternative for patients with comorbidities, including pulmonary dysfunction and/or poorer performance scores, before auto-HSCT.

Pulmonary rehabilitation improves exercise capacity, health-related quality of life, and cardiopulmonary function in patients with non-small cell lung cancer

BACKGROUND

Lung cancer significantly impairs exercise capacity and health-related quality of life (HRQL). Pulmonary rehabilitation (PR) has demonstrated positive effects on exercise capacity and HRQL in lung cancer patients. However, its impact on cardiopulmonary function needs further exploration. The aim of this study was to explore the effects of PR on cardiopulmonary function, exercise capacity and HRQL in patients with lung cancer.

METHODS

Patients with lung cancer were enrolled in a 12-week PR program. Each participant underwent a thorough evaluation, which included spirometry, cardiopulmonary exercise testing, respiratory muscle strength test, and evaluation of HRQL using the Chronic Obstructive Pulmonary Disease Assessment Test (CAT).

RESULTS

Fifty-six patients completed the PR program. Following PR, exercise capacity significantly improved, as evidenced by increased peak oxygen uptake and work rate (both p < 0.05). Exertional symptoms were notably reduced, including leg soreness and dyspnea at peak exercise, accompanied by a decrease in the CAT score (all p < 0.05). Furthermore, improvements in cardiopulmonary function were observed, encompassing respiratory muscle strength, ventilatory equivalent, tidal volume, stroke volume index, and cardiac index at peak exercise (all p < 0.05).

CONCLUSIONS

PR demonstrated notable enhancements in cardiopulmonary function, exertional symptoms, exercise capacity, and HRQL in patients with lung cancer.

Long-term outcomes of pulmonary embolism in children and adolescents

ABSTRACT

Knowledge regarding the long-term consequences of pulmonary embolism (PE) in children is limited. This cohort study describes the long-term outcomes of PE in children who were followed-up at a single-center institution using a local protocol that included clinical evaluation, chest imaging, echocardiography, pulmonary function tests, and cardiopulmonary exercise tests at follow-up, starting 3 to 6 months after acute PE. Children objectively diagnosed with PE at age 0 to 18 years, who had ≥6 months of follow-up were included. Study outcomes consisted of PE resolution, PE recurrence, death, and functional outcomes (dyspnea, impaired pulmonary or cardiac function, impaired aerobic capacity, and post-PE syndrome). The frequency of outcomes was compared between patients with/without underlying conditions. In total, 150 patients were included; median age at PE was 16 years (25th-75th percentile, 14-17 years); 61% had underlying conditions. PE did not resolve in 29%, recurrence happened in 9%, and death in 5%. One-third of patients had at least 1 documented abnormal functional finding at follow-up (ventilatory impairments, 31%; impaired aerobic capacity, 31%; dyspnea, 26%; and abnormal diffusing capacity of the lungs to carbon monoxide, 22%). Most abnormalities were transient. When alternative explanations for the impairments were considered, the frequency of post-PE syndrome was lower, ranging between 0.7% and 8.5%. Patients with underlying conditions had significantly higher recurrence, more pulmonary function and ventilatory impairments, and poorer exercise capacity. Exercise intolerance was, in turn, most frequently because of deconditioning than to respiratory or cardiac limitation, highlighting the importance of physical activity promotion in children with PE.

Butyrate supplementation reduces sarcopenia by repairing neuromuscular junction in patients with chronic obstructive pulmonary disease

INTRODUCTION

Chronic obstructive pulmonary disease (COPD) is associated with an intestinal leak and neuromuscular junction (NMJ) degradation, which contributes to physical compromise and accelerated age-related muscle loss, called sarcopenia. However, the relevant interventions partly remain ineffective. We investigated the effects of exogenous butyrate on sarcopenia and physical capacity with relevance to intestinal permeability and NMJ integrity in COPD patients.

METHODS

COPD patients were randomized into placebo (n = 67) and butyrate (n = 64) groups in a double-blind manner. The patients in the butyrate group received one 300 mg capsule a day for 12 weeks. We measured circulating markers of intestinal leak (zonulin), systemic bacterial load (LBP), and NMJ loss (CAF22), along with handgrip strength (HGS), and short physical performance battery (SPPB) at baseline and 12 weeks.

RESULTS

Butyrate supplementation improved HGS and gait speed in COPD patients. Among SPPB indices, butyrate improved the ability to maintain postural balance and walking and prevented a decline in the ability to rise from a chair. Butyrate also reduced the plasma levels of zonulin, LBP, and CAF22 levels in COPD patients (all p < 0.05). Regression analysis revealed significant associations of plasma zonulin and CAF22 with HGS, gait speed, and cumulative SPPB scores in butyrate group. These changes were associated with reduced markers of inflammation and muscle damage.

CONCLUSION

Butyrate may provide a therapeutic approach to sarcopenia and physical dependency in COPD by repairing intestinal leak and NMJ loss.

Echocardiography and pulmonary hypertension in patients with chronic obstructive pulmonary disease undergoing lung transplantation evaluation

BACKGROUND

The use of echocardiography in pulmonary hypertension (PH) in advanced chronic obstructive pulmonary disease (COPD) is understudied. We aimed to compare the performance of echocardiography with right heart catheterization (RHC) in the diagnosis of PH in COPD patients undergoing lung transplant evaluation.

METHODS

We included 111 patients with severe COPD who underwent RHC in a single center as part of lung transplantation evaluation. COPD-PH and severe COPD-PH were defined based on RHC per the 6th world symposium on pulmonary hypertension. Echocardiographic probability of PH was described according to the European Society of Cardiology guidelines. Summary and univariate analyses were performed.

RESULTS

The mean age (±SD) was 62 (8) and 47% (n=52) were men. A total of 82 patients (74 %) had COPD-PH. The sensitivity, specificity, positive predictive, and negative predictive values of echocardiography in diagnosing COPD-PH were 43 %, 83 %, 88 %, and 34 % respectively and for severe COPD-PH were 67 %, 75 %, 50 %, and 86 % respectively. Echocardiography was consistent with RHC in ruling in/out PH in 53% (n=59) of patients. After controlling for age, sex. BMI, pack year, echocardiography-RHC time difference, GOLD class, FVC, and CT finding of emphysema, higher TLC decreased consistency (parameter estimate=-0.031; odds ratio: 0.97, 95%CI 0.94-0.99; p=0.037) and higher DLCO increased consistency (parameter estimate=0.070; odds ratio: 1.07, 95%CI 0.94-0.99; p=0.026).

CONCLUSIONS

Echocardiography has high specificity but low sensitivity for the diagnosis of PH in advanced COPD. Its performance improves when ruling out severe COPD-PH. This performance correlates inversely with lung hyperinflation.

Development and evaluation of a computerized algorithm for the interpretation of pulmonary function tests

Pulmonary function tests (PFTs) are usually interpreted by clinicians using rule-based strategies and pattern recognition. The interpretation, however, has variabilities due to patient and interpreter errors. Most PFTs have recognizable patterns that can be categorized into specific physiological defects. In this study, we developed a computerized algorithm using the python package (pdfplumber) and validated against clinicians' interpretation. We downloaded PFT reports in the electronic medical record system that were in PDF format. We digitized the flow volume loop (FVL) and extracted numeric values from the reports. The algorithm used FEV1/FVC<0.7 for obstruction, TLC<80%pred for restriction and <80% or >120%pred for abnormal DLCO. The algorithm also used a small airway disease index (SADI) to quantify late expiratory flattening of the FVL to assess small airway dysfunction. We devised keywords for the python Natural Language Processing (NLP) package (spaCy) to identify obstruction, restriction, abnormal DLCO and small airway dysfunction in the reports. The algorithm was compared to clinicians' interpretation in 6,889 PFTs done between March 1st, 2018, and September 30th, 2020. The agreement rates (Cohen's kappa) for obstruction, restriction and abnormal DLCO were 94.4% (0.868), 99.0% (0.979) and 87.9% (0.750) respectively. In 4,711 PFTs with FEV1/FVC≥0.7, the algorithm identified 190 tests with SADI < lower limit of normal (LLN), suggesting small airway dysfunction. Of these, the clinicians (67.9%) also flagged 129 tests. When SADI was ≥ LLN, no clinician's reports indicated small airway dysfunction. Our results showed the computerized algorithm agreed with clinicians' interpretation in approximately 90% of the tests and provided a sensitive objective measure for assessing small airway dysfunction. The algorithm can improve efficiency and consistency and decrease human errors in PFT interpretation. The computerized algorithm works directly on PFT reports in PDF format and can be adapted to incorporate a different interpretation strategy and platform.

Comparison of Free-Breathing 3D Phase-Resolved Functional Lung (PREFUL) MRI With Dynamic 19 F Ventilation MRI in Patients With Obstructive Lung Disease and Healthy Volunteers

BACKGROUND

Non-contrast-enhanced 1 H magnetic resonance imaging (MRI) with full lung coverage shows promise for assessment of regional lung ventilation but a comparison with direct ventilation measurement using 19 F MRI is lacking.

PURPOSE

To compare ventilation parameters calculated using 3D phase-resolved functional lung (PREFUL) MRI with 19 F MRI.

STUDY TYPE

Prospective.

POPULATION

Fifteen patients with asthma, 14 patients with chronic obstructive lung disease, and 13 healthy volunteers.

FIELD STRENGTH/SEQUENCE

A 3D gradient-echo pulse sequence with golden-angle increment and stack-of-stars encoding at 1.5 T.

ASSESSMENT

All participants underwent 3D PREFUL MRI and 19 F MRI. For 3D PREFUL, static regional ventilation (RVent) and dynamic flow-volume cross-correlation metric (FVL-CM) were calculated. For both parameters, ventilation defect percentage (VDP) values and ventilation defect (VD) maps (including a combination of both parameters [VDPCombined ]) were determined. For 19 F MRI, images from eight consecutive breaths under volume-controlled inhalation of perfluoropropane were acquired. Time-to-fill (TTF) and wash-in (WI) parameters were extracted. For all 19 F parameters, a VD map was generated and the corresponding VDP values were calculated.

STATISTICAL TESTS

For all parameters, the relationship between the two techniques was assessed using a Spearman correlation (r). Differences between VDP values were compared using Bland-Altman analysis. For regional comparison of VD maps, spatial overlap and Sørensen-Dice coefficients were computed.

RESULTS

3D PREFUL VDP values were significantly correlated to VDP measures by 19 F (r range: 0.59-0.70). For VDPRVent , no significant bias was observed with VDP of the third and fourth breath (bias range = -6.8:7.7%, P range = 0.25:0.30). For VDPFVL-CM , no significant bias was found with VDP values of fourth-eighth breaths (bias range = -2.0:12.5%, P range = 0.12:0.75). The overall spatial overlap of all VD maps increased with each breath, ranging from 61% to 81%, stabilizing at the fourth breath.

DATA CONCLUSION

3D PREFUL MRI parameters showed moderate to strong correlation with 19 F MRI. Depending on the 3D PREFUL VD map, the best regional agreement was found to 19 F VD maps of third-fifth breath.

LEVEL OF EVIDENCE

3 TECHNICAL EFFICACY: Stage 2.

The initial angle of the maximum expiratory flow-volume curve: a novel start-of-test criteria of spirometry in children

The aim of the present study was to define an initial angle called β and to assess its diagnostic value for identifying poor-quality maneuvers in spirometry testing in children. Furthermore, its predictive equation or normal value was explored. Children aged 4-14 years with respiratory symptoms who underwent spirometry were enrolled. Based on the efforts labeled during maneuvering and the quality control criteria of the guidelines, children were categorized into good-quality and poor-quality groups. According to ventilatory impairment, children in the good-quality group were divided into three subgroups: normal, restricted, and obstructed. Angle β was the angle between the line from the expiratory apex to the origin of coordinates and the x-axis of the maximal expiratory flow-volume (MEFV) curve. Demographic characteristics, angle β, and other spirometric parameters were compared among groups. The diagnostic values of angle β, forced expiratory time (FET), and their combination were assessed using receiver operating characteristic curves. Data from 258 children in the good-quality group and 702 healthy children in our previous study were used to further explore the predictive equation or normal value of angle β. The poor-quality group exhibited a significantly smaller angle β (76.44° vs. 79.36°; P < 0.001), significantly lower peak expiratory flow (PEF), FET, and effective FET (ETe), and significantly higher expiratory volume at peak flow rate (FEV-PEF) and ratio of extrapolated volume and forced vital capacity (EV/FVC) than the good-quality group. There was no significant difference in angle β among the normal, restricted, and obstructed groups. Logistic regression analysis revealed that smaller angle β and FET values indicated poor-quality MEFV curves. The combination of angle β < 74.58° and FET < 4.91 s had a significantly larger area under the curve than either one alone. The normal value of angle β of children aged 4-14 years was 78.40 ± 0.12°.   Conclusions: Angle β contributes to the quality control evaluation of spirometry in children. Both angle β < 74.58° and FET < 4.91 s are predictors of poor-quality MEFV curves, while their combination offers the highest diagnostic value. What is Known: • A slow start is one of the leading causes of poor-quality maximal expiratory flow-volume (MEFV) curves, which is a particularly prominent issue among children due to limited cooperation, especially those younger than 6 years old. • It is relatively difficult to differentiate between ventilatory dysfunction and poor cooperation when a slow start occurs in children; therefore, there is an urgent need for an objective indicator that is unaffected by ventilatory impairment to evaluate quality control of spirometry. What is New: • The initial angle β, which was introduced at the ascending limb of the MEFV curve in the present study, has a certain diagnostic value for poor-quality MEFV curves in children. • Angle β < 74.58° is a predictor of poor-quality MEFV curves, and its combination with FET < 4.91 s offers a higher diagnostic value.

High-intensity aerobic exercise training improves exercise capacity, dyspnea, and fatigue in patients with severe asthma using triple inhaler

Objectives

Asthma is a chronic respiratory disease that affects millions of people worldwide and causes severe symptoms such as wheezing, coughing, and breathing difficulty. Despite modern treatments, 3%-10% of patients develop severe asthma, which requires high-dose medications, and they may still experience frequent and severe symptoms, exacerbations, and psychological impacts. This study aimed to investigate the effects of high-intensity aerobic exercise training (HIAET) in patients with severe asthma.

Materials and Methods

Patients with severe asthma were recruited, and cardiopulmonary exercise tests, dyspnea, and leg fatigue scores were performed before HIAET. Participants underwent a 12-week hospital-based HIAET, which involved exercising twice weekly to reach 80% of their peak oxygen uptake (VO2).

Results

Eighteen patients with severe asthma underwent HIAET, which resulted in significant improvement in peak VO2 (1214.0 ± 297.9-1349.4 ± 311.2 mL/min, P = 0.004) and work rate (80.6 ± 21.2-96.2 ± 24.8 watt, P < 0.001) and decrease in dyspnea (5.1 ± 1.8-4.1 ± 1.2, P = 0.017) and fatigue scores (5.2 ± 2.3-4.0 ± 1.2, P = 0.020) at peak exercise. No significant changes were observed in spirometry results, respiratory muscle strength, or circulatory parameters.

Conclusion

HIAET can lead to improved exercise capacity and reduced dyspnea and fatigue scores at peak exercise without changes in spirometry, respiratory muscle strength, and circulatory parameters.

Adding oscillometry to spirometry in guidelines better identifies uncontrolled asthma, future exacerbations, and potential targeted therapy

The objective of this review is to provide new advances in our understanding of the clinical importance of establishing peripheral airway impairment (PAI) by impulse oscillometry (IOS) and targeted therapy, which could result in better asthma outcomes. Data sources include PubMed and Google search, limited to English language and human disease, with key words IOS and asthma. Key findings include PAI being consistently associated with uncontrolled asthma across ethnicities, using IOS reference equations factoring Hispanic and White reference algorithms. It is noted that PAI is common even in patients considered well-controlled by asthma guidelines. In a large longitudinal analysis (Assessment of Small Airways Involved in Asthma or ATLANTIS study), a composite of R5-R20, AX, and X5 ordinal scores were independently predictive of asthma control and exacerbation in a multivariate analysis, but forced expiratory volume in 1 second was not significantly predictive of morbidities. However, combining forced expiratory volume in 1 second less than 80% with PAI resulted in greater odds of identifying uncontrolled asthma and exacerbations, than either alone. Applying an external validation method in children with asthma offers the clinician the IOS reference equations best fit for their own specific population. Several clinical phenotypes can also identify PAI with high probability, useful when IOS is not available. Poor asthma outcomes for obese patients with asthma are associated with dysanapsis and PAI, not obesity alone. Extrafine inhaled corticosteroids achieve better asthma control and improve peripheral airway function with fewer exacerbations at lower dosages than nonextrafine inhaled corticosteroid aerosols. In conclusion, these data support the benefit of adding IOS to spirometry in future asthma guidelines and suggest the potential benefit from targeted therapy.

Validity of the Espiro Mobile Application in the Interpretation of Spirometric Patterns: An App Accuracy Study

Spirometry is a pulmonary function test where correct interpretation of the results is crucial for accurate diagnosis of disease. There are online tools to assist in the interpretation of spirometry results; however, as yet none are validated. We evaluated the interpretation accuracy of the Espiro app using pulmonologist interpretations as the gold standard. This is an observational descriptive study in which 118 spirometry results were interpreted by the Espiro app, two pulmonologists, two primary care physicians, and two residents of a primary care training program. We determined the interpretation accuracy of the Espiro app and the concordance of the pattern and severity interpretation between the Espiro app and each of the observers using Cohen's kappa coefficient (k). We obtained a sensitivity and specificity for the Espiro app of 97.5% (95% confidence interval (CI): 86.8-99.9%) and 94.9% (95%CI: 87.4-98.6%) with pulmonologist 1 and 100% (95%CI: 91.6-100%) and 98.7% (95%CI: 92.9-99.9%) with pulmonologist 2. The concordance for the pattern interpretation was greater than k 0.907, representing almost perfect agreement. The concordance of the severity interpretation was greater than k 0.807, representing substantial to almost perfect agreement. We concluded that the Espiro app is a valid tool for spirometry interpretation.

Can static hyperinflation predict exercise capacity in COPD?

INTRODUCTION

The diagnosis and severity assessment of COPD relies on spirometry, and in particular the FEV1. However, it has been proposed that hyperinflation and air-trapping are better predictors of exercise capacity and mortality than the FEV1.

RESEARCH

QUESTION: Does static hyperinflation predict exercise capacity?

METHODS

We conducted an observational prospective study. Patients with COPD referred to the lung function laboratory were consecutively recruited. Patients with hyperinflation (the experimental group) were compared to patients without hyperinflation (the control group). The sample sizes were determined assuming an effect size of 0.5 and a power of 0.80.

RESULTS

We recruited 124 participants, of whom 87% were male, the mean age was 66.1 ± 8.8 years. 67% were symptomatic (GOLD B or D). Airflow limitation was moderate to severe in the majority of patients (median FEV1 47%, IQR 38-65%) and 43% of patients had static hyperinflation. The median 6MWD was 479 meters (404-510) and peak workload in CPET was 64 watts (46-88) with peak VO2 1.12 L/min, 0.89-1.31 L/min. Patients with lower FEV1, DLCO and IC/TLC and higher RV/TLC had reduced exercise capacity in both 6MWT and CPET, measured as lower distance, greater desaturation and ∆Borg dyspnoea, and reduced workload, peak VO2 and peak VE and higher desaturation and ventilatory limitation (VE/MVV). An IC/TLC < 0.33 predicted reduced exercise performance (peak O2 <60%). Dyspnoea assessed by mMRC and QoL measured by CAT and CCQ were also worse in the hyperinflation in COPD patients.

CONCLUSION

In COPD patients, IC/TLC and RV/TLC are valuable predictors of exercise performance in both 6MWT and CPET and PRO.

Association between viral hepatitis and metabolic syndrome in lung function impairment: A Taiwan community-based study

OBJECTIVES

Metabolic syndrome (MetS) and hepatitis C virus (HCV) are associated with a higher risk of impaired pulmonary function (iPF). This study aimed to investigate the relationships among MetS, iPF, and viral hepatitis.

METHODS

This community-based study enrolled participants undergoing annual health check-ups in southern Taiwan between March and December 2019. We performed multivariable logistic regression analyses adjusted for demographics and characteristics to identify the factors associated with iPF.

RESULTS

A total of 2337 participants completed examinations, of whom 928 (39.7%) had iPF. The participants with iPF were elderly (68.8  ±  12.8 years old) and predominately female (63%). MetS increased the risk of iPF (odds ratio (OR) 1.51, 95% confidence interval (CI) 1.27-1.81, p < 0.001). Beyond age (OR 1.03, 95% CI 1.02-1.04) and smoking (OR 1.309, 95% CI 1.004-1.705), female sex (OR 0.74, 95% CI 0.59-0.93) and high education level (OR 0.96, 95% CI 0.94-0.98, p < 0.001) protected against iPF. HCV was not significantly associated with iPF (OR 1.17, 95% CI 0.90-1.52, p  =  0.235) in multivariable analysis. MetS was associated with a higher risk of iPF in the non-HBV/HCV group (OR 1.86, 95% CI 1.54-2.26) and HBV alone group (OR 3.44, 95% CI 1.89-6.28), but not in the HCV alone group (OR 1.02, 95% CI 0.64-1.62).

DISCUSSION

MetS was an independent predictor of iPF, especially the restrictive type, and had different effects in the HBV/non-viral hepatitis and HCV groups. Female sex and education were inversely associated with iPF.

Prenatal exposure to metal mixtures and lung function in children from the New Hampshire birth cohort study

Prenatal exposure to metals/metalloids, even at common US population levels, may pose risks to fetal health, and affect children's lung function. Yet, the combined effects of simultaneous prenatal exposures on children's lung function remain largely unexplored. This study analyzed 11 metals (As speciation, Cd, Co, Cu, Mo, Ni, Pb, Sb, Se, Sn, Zn) in maternal urine during weeks 24-28 of gestation and evaluated lung function, including forced vital capacity (FVC) and forced expiratory volume in the first second of expiration (FEV1), in 316 US mother-child pairs at around age 7. We used Bayesian Kernel Machine Regression (BKMR), weighted quantile sum regression (WQSR), and multiple linear regression to examine the association between metal mixture exposure and children's lung function, adjusting for maternal smoking, child age, sex, and height. In BKMR models assessing combined exposure effects, limited evidence of metal non-linearity or interactions was found. Nevertheless, Co, As species, and Pb showed a negative association, while Mo exhibited a positive association with children's FVC and FEV1, with other metals held constant at their medians. The weighted index, from WQSR analysis assessing the cumulative impact of all metals, highlighted prenatal Mo with the highest positive weight, and Co, As, and Sb with the most substantial negative weights on children's FVC and FEV1. Urinary Co and Pb were negatively associated with FVC (β = -0.09, 95% confidence interval (CI) (-0.18; -0.01) and β = -0.07, 95% CI (-0.13; 0.00), respectively). Co was also negatively associated with FEV1 (β = -0.09, 95% CI (-0.18; 0.00). There was a negative association between As and FVC, and a positive association between Mo and both FVC and FEV1, though with wide confidence intervals. Our findings suggest that prenatal trace element exposures may impact children's lung function, emphasizing the importance of reducing toxic exposures and maintaining adequate nutrient levels.

Exercise-induced desaturation during a six-minute walk test is associated with poor clinical outcomes in patients with pulmonary arterial hypertension

BACKGROUND

The six-minute walk test (6MWT) is an established exercise test for patients with pulmonary arterial hypertension (PAH), affording insight into both exercise intolerance and overall prognosis. Despite the widespread application of the 6MWT, the prognostic implications of exercise-induced desaturation (EID) during this test has been inadequately studied in PAH patients. Thus, we evaluated the occurrence of EID and its prognostic significance in PAH patients.

METHODS

We analyzed PAH patients in a single-center cohort from April 2016 to March 2021. EID was defined as a reduction in oxygen saturation exceeding 4% from the baseline or to below 90% at any point during the test.

RESULTS

We analyzed 20 PAH patients in this cohort, primarily consisting of 16 females with an average age of 48.4 ± 13.3 years. Among them, ten exhibited EID. Baseline characteristics, echocardiographic data and right heart catheterization data were similar between the two groups. However, total distance (354.3 ± 124.4 m vs. 485.4 ± 41.4 m, P = 0.019) and peak oxygen uptake (12.9 ± 3.2 mL/kg⋅min vs. 16.4 ± 3.6 mL/kg⋅min, P = 0.019) were significantly lower in the EID group. During the total follow-up duration of 51.9 ± 25.7 months, 17 patients had at least one adverse clinical event (2 deaths, 1 lung transplantation, and 13 hospital admissions). The presence of EID was associated with poor clinical outcome (hazard ratio = 6.099, 95% confidence interval = 1.783-20.869, P = 0.004).

CONCLUSIONS

During the 6MWT, EID was observed in a half of PAH patients and emerged as a significant prognostic marker for adverse clinical events.

Association of preoperative frailty with pulmonary complications after cardiac surgery in elderly individuals: a prospective cohort study

BACKGROUND

The relationship between preoperative frailty and pulmonary complications after cardiac surgery in elderly patients is unclear. This study was designed to evaluate the relationship between frailty and postoperative pulmonary complications (PPCs) in elderly patients undergoing cardiac surgery and to provide a basis for their prevention and treatment.

AIMS

This study aimed to investigate the predictive value of preoperative frailty on pulmonary complications after cardiac surgery in elderly patients.

METHODS

Frailty was assessed using the CAF. The diagnosis of PPCs was based on the criteria defined by Hulzebos et al., and patients were classified into a PPCs group and a non-PPCs group. Factors with clinical significance and P < 0.05 in univariate regression analysis were included in multivariate logistic regression analysis to determine the relationship between preoperative frailty and PPCs. The area under the receiver operating characteristic (ROC) curve (AUC) was used to compare the predictive effects of the CAF, EuroSCORE II, and ASA + age on the occurrence of PPCs.

RESULTS

A total of 205 patients were enrolled in this study, 31.7% of whom developed PPCs. Univariate logistic regression analysis showed that frailty, ASA grade, EuroSCORE II, hemoglobin concentration, FVC, time of operation, and postoperative AKI were associated with the development of PPCs. However, after adjustments for all possible confounding factors, multivariate logistic regression results showed that frailty, prolonged operation time, and postoperative AKI were risk factors for PPCs, and the risk of postoperative PPCs in frail patients was approximately 4.37 times that in nonfrail patients (OR = 4.37, 95%CI: 1.6-11.94, P < 0.05). The predictive efficacy of the traditional perioperative risk assessment tools EuroSCORE II and ASA + age was lower than that of CAF.

CONCLUSIONS

Frailty before surgery, prolonged operation time, and postoperative AKI were independent risk factors for pulmonary complications after heart surgery in elderly individuals, and CAF was more effective than the traditional risk predictors EuroSCORE II and ASA + age.

Quantitative CT Scan Imaging of the Airways for Diagnosis and Management of Lung Disease

CT scan imaging provides high-resolution images of the lungs in patients with chronic respiratory diseases. Extensive research over the last several decades has focused on developing novel quantitative CT scan airway measurements that reflect abnormal airway structure. Despite many observational studies demonstrating that associations between CT scan airway measurements and clinically important outcomes such as morbidity, mortality, and lung function decline, few quantitative CT scan measurements are applied in clinical practice. This article provides an overview of the relevant methodologic considerations for implementing quantitative CT scan airway analyses and provides a review of the scientific literature involving quantitative CT scan airway measurements used in clinical or randomized trials and observational studies of humans. We also discuss emerging evidence for the clinical usefulness of quantitative CT scan imaging of the airways and discuss what is required to bridge the gap between research and clinical application. CT scan airway measurements continue to improve our understanding of disease pathophysiologic features, diagnosis, and outcomes. However, a literature review revealed a need for studies evaluating clinical benefit when quantitative CT scan imaging is applied in the clinical setting. Technical standards for quantitative CT scan imaging of the airways and high-quality evidence of clinical benefit from management guided by quantitative CT scan imaging of the airways are required.

Clinic vs Home Spirometry for Monitoring Lung Function in Patients With Asthma

BACKGROUND

Studies examining agreement between home and clinic spirometry in patients with asthma are limited, with conflicting results. Understanding the strengths and limitations of telehealth and home spirometry is particularly important considering the SARS-CoV-2 pandemic.

RESEARCH QUESTION

How well do home and clinic measurements of trough FEV1 agree in patients with uncontrolled asthma?

STUDY DESIGN AND METHODS

This post hoc analysis used trough FEV1 data from the randomized double-anonymized parallel-group phase 3A CAPTAIN (205715; NCT02924688) and phase 2B 205832 (NCT03012061) trials in patients with uncontrolled asthma. CAPTAIN evaluated the impact of adding umeclidinium to fluticasone furoate/vilanterol via a single inhaler; the 205832 trial investigated adding umeclidinium to fluticasone furoate vs placebo. Trough FEV1 measurements were collected via home spirometry and supervised in-person spirometry in the research clinic. To compare home and clinic spirometry, we examined the time-course analyses of home and clinic trough FEV1, and generated post hoc Bland-Altman plots to assess agreement between home and clinic spirometry.

RESULTS

Data from 2,436 patients (CAPTAIN trial) and 421 patients (205832 trial) were analyzed. Treatment-related improvements in FEV1 were observed in both trials, using home and clinic spirometry. Improvements measured by home spirometry were of lower magnitude and less consistent than clinic measurements. Bland-Altman plots suggested poor agreement between home and clinic trough FEV1 at baseline and week 24.

INTERPRETATION

This post hoc comparison of home and clinic spirometry is the largest conducted in asthma. Results showed that home spirometry was less consistent than and lacked agreement with clinic spirometry, suggesting that unsupervised home readings are not interchangeable with clinic measurements. However, these findings may only be applicable to home spirometry using the specific device and coaching methods employed in these studies. Postpandemic, further research to optimize home spirometry use is needed.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov; Nos.: NCT03012061 and NCT02924688; URL: www.

CLINICALTRIALS

gov.

Evaluation of the relationship of tricuspid regurgitation peak gradient/tricuspid annulus plane systolic excursion to exercise capacity, cardiac index, and ventilatory function during exercise in patients with COPD

BACKGROUND

Chronic obstructive pulmonary disease (COPD) often causes cardiopulmonary dysfunction, which deteriorates exercise capacity. Cardiopulmonary exercise testing (CPET) and echocardiography are common tools for evaluating cardiovascular function. No studies have analyzed the correlation between echocardiography-derived parameters and cardiopulmonary response during exercise.

OBJECTIVES

We analyzed the correlation between echocardiographic parameters such as tricuspid regurgitation peak gradient (TRPG), tricuspid annular plane systolic excursion (TAPSE), TRPG/TAPSE and CPET-derived parameters.

METHODS

Seventy-seven patients with COPD were evaluated. We analyzed the correlation between parameters derived from echocardiography, exercise capacity, cardiovascular and ventilatory parameters derived from CPET.

RESULTS

The correlation between TRPG/TAPSE and work rate (WR) was moderate and negative (-0.4423, p = 0.0003), while TRPG had a weak negative correlation with WR (r= -0.3099, p = 0.0127). Oxygen uptake at peak exercise was weakly negatively correlated with TRPG/TAPSE (-0.3404, p = 0.0059), TRPG (r= -0.3123, p = 0.0120), and the ratio of early mitral inflow velocity to early mitral annular diastolic velocity (E/E'). The correlation between TRPG/TAPSE and exercise capacity was higher than that of TPRG, TAPSE, and E/E'. TRPG/TAPSE exhibited a moderate negative correlation with cardiac index, whereas TRPG and TAPSE showed a weak correlation. The correlation between TRPG/TAPSE and cardiac function during exercise was higher than that of TPRG, TAPSE, and E/E'. TRPG/TAPSE, TRPG, TAPSE, and E/E' were weakly negatively correlated with lung function.

CONCLUSIONS

In assessing exercise capacity, cardiac function, and gas exchange, TRPG/TAPSE proves to be superior to other cardiac parameters. Higher TRPG/TAPSE levels corresponded to lower exercise capacity, cardiovascular and ventilatory function.

Association between clinical, serological, functional and radiological findings and ventilatory distribution heterogeneity in patients with rheumatoid arthritis

BACKGROUND

In rheumatoid arthritis (RA), the involvement of the pulmonary interstitium can lead to structural changes in the small airways and alveoli, leading to reduced airflow and maldistribution of ventilation. The single-breath nitrogen washout (SBN2W) test is a measure of the ventilatory distribution heterogeneity and evaluates the small airways. This study aimed to find out which clinical, serological, functional and radiological findings are useful to identify RA patients with pathological values of the phase III slope (SIII) measured by the SBN2W test.

METHODS

This was a cross-sectional study in which RA patients were assessed using the Health Assessment Questionnaire-Disability Index (HAQ-DI) and the Clinical Disease Activity Index (CDAI) and underwent serological analysis of autoantibodies and inflammatory markers. In addition, they underwent pulmonary function tests (including the SBN2W test) and chest computed tomography (CT).

RESULTS

Of the 60 RA patients evaluated, 39 (65%) had an SIII >120% of the predicted value. There were significant correlations between SIII and age (r = 0.56, p<0.0001), HAQ-DI (r = 0.34, p = 0.008), forced vital capacity (FVC, r = -0.67, p<0.0001), total lung capacity (r = -0.46, p = 0.0002), residual volume/total lung capacity (TLC) (r = 0.44, p = 0.0004), and diffusing capacity of the lungs for carbon monoxide (r = -0.45, p = 0.0003). On CT scans, the subgroup with moderate/severe disease had a significantly higher SIII than the normal/minimal/mild subgroup (662 (267-970) vs. 152 (88-283)% predicted, p = 0.0004). In the final multiple regression model, FVC, extent of moderate/severe involvement and age were associated with SIII, explaining 59% of its variability.

CONCLUSIONS

In patients with RA, FVC, extent of lung involvement and age, all of which are easily obtained variables in clinical practice, identify poorly distributed ventilation. In addition, the presence of respiratory symptoms and deteriorated physical function are closely related to the distribution of ventilation in these patients.

Acupuncture as adjunctive therapy for patients with AECOPD: study protocol for a multicenter, randomized controlled trial

Background

The acute exacerbation of chronic obstructive pulmonary disease (AECOPD) is a common respiratory disease among older adults, which imposes a significant burden on individuals and society and poses a major challenge to the global public health system due to its high morbidity and mortality. Acupuncture is effective for AECOPD, but its efficacy has been questioned due to the limited methodological quality. Thus, we aim to investigate the efficacy of acupuncture as adjunctive therapy for AECOPD and determine whether the efficacy of acupuncture differs with the type of acupoint combinations.

Methods and analysis

This study proposes a prospective, multicenter randomized controlled trial that will comprise four groups, including two acupuncture treatment groups, one sham acupuncture group, and one basic treatment group. The acupuncture treatment groups will be distinguished by their focus on different patterns of acupoint combination, namely the Xi-cleft and He-sea acupoint combination and the Eight Confluence points acupoint combination, which may vary in clinical efficacy based on traditional acupuncture theories. The study aims to randomize 556 patients in a 1:1:1:1 ratio across the four groups. Each patient in acupuncture group or sham acupuncture group will receive routine drug therapy and 7 sessions of acupuncture treatment over 1 week. Participants in the basic treatment group will only receive routine drug therapy. The trial will be conducted in seven hospitals located in China. The primary outcomes in this trial will include differences in the Breathlessness, Cough, and Sputum Scale (BCSS) before randomization, 7 days after randomization, 5 and 9 weeks after randomization.

Ethics and dissemination

Ethical approval was obtained from the Sichuan Regional Ethics Review of Committee on Traditional Chinese Medicine (Approval ID: 2022KL-068). The results of this study will be distributed through peer-reviewed journals.Clinical Trial Registration: ClinicalTrials.gov, identifier ChiCTR2200064484.

Association between spirometry pattern, left ventricular diastolic function, and mortality

BACKGROUND

Spirometric abnormalities have been related to incident heart failure in general population, who generally have preserved left ventricular ejection fraction (LVEF). We aimed to investigate the association between spirometric indices, cardiac functions and clinical outcomes.

METHODS

Subjects presenting with exertional dyspnoea and received spirometry and echocardiography were eligible for this study. Forced vital capacity (FVC) and forced expiratory volume in the first second (FEV1)/FVC ratio were measured to define the spirometry patterns: normal (FEV1/FVC ≥ 70%, FVC ≥ 80%), obstructive (FEV1/FVC < 70%, FVC ≥ 80%), restrictive pattern (FEV1/FVC ≥ 70%, FVC < 80%) and mixed (FEV1/FVC < 70%, FVC < 80%). The diastolic dysfunction index (DDi) was the counts of the indicators, including septal e' velocity <7 cm/s, septal E/e' > 15, pulmonary artery systolic pressure > 35 mmHg and left atrial dimension >40 mm.

RESULTS

Among a total of 8669 participants (65.8 ± 16.3 years, 56% men), 3739 (43.1%), 829 (9.6%), 3050 (35.2%) and 1051 (12.1%) had normal, obstructive, restrictive and mixed spirometry pattern, respectively. Subjects with restrictive or mixed spirometry pattern had higher DDi and worse long-term survival than those with obstructive or normal ventilation. FVC but not FEV1/FVC was predictive of 5-year mortality, independent of age, sex, renal function, LVEF, DDi, body mass index, and comorbidities (hazard ratio, 95% confidence intervals: .981, .977-.985). Furthermore, there was an inverse nonlinear relationship between FVC and DDi, suggesting the declined FVC may mediate 43% of the prognostic hazard of left ventricular diastolic dysfunction.

CONCLUSIONS

The restrictive spirometry pattern or the declined FVC was associated with left ventricular diastolic dysfunction, which aggravated the long-term mortality in the ambulatory dyspnoeic subjects.

European Respiratory Society/American Thoracic Society technical statement: standardisation of the measurement of lung volumes, 2023 update

This document updates the 2005 European Respiratory Society (ERS) and American Thoracic Society (ATS) technical standard for the measurement of lung volumes. The 2005 document integrated the recommendations of an ATS/ERS task force with those from an earlier National Heart, Lung, and Blood Institute workshop that led to the publication of background papers between 1995 and 1999 and a consensus workshop report with more in-depth descriptions and discussion. Advancements in hardware and software, new research and emerging approaches have necessitated an update to the 2005 technical standard to guide laboratory directors, physiologists, operators, pulmonologists and manufacturers. Key updates include standardisation of linked spirometry, new equipment quality control and validation recommendations, generalisation of the multiple breath washout concept beyond nitrogen, a new acceptability and grading system with addition of example tracings, and a brief review of imaging and other new techniques to measure lung volumes. Future directions and key research questions are also noted.

Reference value for the 6-min walking distance in women with systemic sclerosis considering the impact of muscle strength

BACKGROUND

Early triage, the search for new therapies, and closer monitoring of patients with systemic sclerosis before their lung function irreversibly deteriorates are urgent concerns. Because it is an independent predictor of systemic sclerosis-related mortality, the 6-min walk test is a potentially useful tool to evaluate outcomes, along with pulmonary function and computed tomography. This study aimed to establish a reference value for the 6-min walking distance in women with diffuse cutaneous systemic sclerosis-associated interstitial lung disease that takes into account the effects of muscle and lung function.

METHODS

This was a cross-sectional study in which 69 women with systemic sclerosis underwent the 6-min walk test, Health Assessment Questionnaire-Disability Index, pulmonary function, handgrip strength test, and quadriceps strength test.

FINDINGS

The mean 6-min walking distance was 447 ± 78 m, and 43.5% of the participants did not reach 80% of their predicted value. 6-min walking distance correlated positively with quadriceps strength (r = 0.418, P = 0.0004), forced vital capacity (r = 0.306, P = 0.011), pulmonary diffusion (r = 0.360, P = 0.002), maximum inspiratory pressure (r = 0.268, P = 0.029), and maximum expiratory pressure (r = 0.288, P = 0.019) and negatively with age (r = -0.378, P = 0.001), body mass index (r = -0.248, P = 0.039), and Health Assessment Questionnaire-Disability Index (r = -0.438, P = 0.0001). In the multiple linear regression analysis, quadriceps strength, body mass index, pulmonary diffusion, age, and maximum expiratory pressure explained 72% of the 6-min walking distance variability.

INTERPRETATION

Muscle function and, to a lesser extent, lung function are key contributors in determining the reference value for the 6-min walking distance in women with diffuse cutaneous systemic sclerosis-associated interstitial lung disease.

Race-neutral equations for assessment of lung function in children with thalassemia

The aim of this study was to assess pulmonary dysfunction in children with transfusion-dependent thalassemia (TDT) using the Global Lung Function Initiative (GLI) 2022 race-neutral spirometric reference equations and to determine the main predicting factors. The spirometric results of 68 children with TDT were compared to the results of 68 healthy control subjects using both GLI-2012 reference equations for Caucasians and GLI-2022 global equations. Associations between the spirometric data and various anthropometric, clinical, and laboratory parameters were analyzed to detect predictors of pulmonary dysfunction in this group of patients. Children with TDT showed significantly lower values of FVC and FEV1 with a predominance of the restrictive pattern (23.53%). Thalassemic children with the restrictive pattern were significantly older, had a longer duration of regular blood transfusion, lower height, weight, and BMI z-scores, higher average serum ferritin, and higher frequency of having a serum ferritin level >2500 ng/mL. The strongest predictor for having a restrictive spirometric pattern was high serum ferritin. Our analysis shows that the transition from GLI-2012 spirometric reference equations for Caucasians to the GLI-2022 global equations has led to a reduction in the prevalence rate of restrictive pulmonary dysfunction in children with TDT, which should not affect the patient outcome in the long term. Asymptomatic children with TDT exhibited a restrictive spirometric pattern in a significant proportion. The most important predictor was high serum ferritin. We encourage the inclusion of pulmonary function testing in the routine monitoring of patients with TDT, especially in older patients and those with iron overload.

Description of a single centre cohort of patients with systemic sclerosis from the University Hospital of Buenos Aires and factors associated with lung function deterioration. A retrospective study

INTRODUCTION

Given the paucity of data in Latin America and especially in Argentina regarding the epidemiology of SSc, the prevalence of ILD, its course, and particularly the response to treatment, our objective was to evaluate a cohort of SSc patients evaluated in a single University Hospital in Buenos Aires.

PATIENTS/METHODS

We included 152 patients with SSc, followed from disease onset to last pulmonary function test and with at least two PFT and up to 30 months between each.

RESULTS

Sixty-one percent had diffuse SSc (DSSc) and 32% limited SSc (LSSc). The only significant clinical differences between these groups were a higher initial mRodnan score and prevalence of ILD in the DSSc. These also had significantly more anti Scl-70 (Topoisomerase 1) antibodies compared to the LSSC group who had significantly more anti centromere antibodies. The DSSc group also had significantly more extensive damage on HRCT with no differences in terms of imaging patterns. Comparing patients with and without ILD by HRCT, those with ILD had significantly more extensive damage, significantly more anti Scl-70 antibodies, and significantly fewer anti centromere antibodies than those without ILD. Patients whose ILD progressed had a smoking history (OR 4.97) and prior immunosuppressive treatment (OR 15.6) (multivariate analysis). Overall disease duration was significantly shorter in those who progressed.

CONCLUSIONS

Our SSc population had similar characteristics to those described elsewhere as well as prevalence of ILD and its progression. We found a shorter disease duration, smoking, and prior immunosuppressive treatment to be associated with ILD progression.

A Comparison of Long-Term Outcomes in Patients Managed With Venovenous Extracorporeal Membrane Oxygenation in the First and Second Waves of the COVID-19 Pandemic in the United Kingdom

OBJECTIVES

Early studies of venovenous extracorporeal membrane oxygenation (ECMO) in COVID-19 have revealed similar outcomes to historical cohorts. Changes in the disease and treatments have led to differences in the patients supported on venovenous ECMO in the first and second waves. We aimed to compare these two groups in both the acute and follow-up phase.

DESIGN

Retrospective single-center cohort study comparing mortality at censoring date (November 30, 2021) and decannulation, patient characteristics, complications and lung function and quality of life (QOL-by European Quality of Life 5 Dimensions 3 Level Version) at first follow-up in patients supported on venovenous ECMO between wave 1 and wave 2 of the COVID-19 pandemic.

SETTING

Critical care department of a severe acute respiratory failure service.

PATIENTS

Patients supported on ECMO for COVID-19 between wave 1 (March 17, 2020, to August 31, 2020) and wave 2 (January 9, 2020, to May 25, 2021).

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

One hundred twenty-three patients were included in our analysis. Survival at censoring date (χ 2 , 6.35; p = 0.012) and decannulation (90.4% vs 70.0%; p < 0.001) was significantly lower in the second wave, while duration of ECMO run was longer (12.0 d [18.0-30.0 d] vs 29.5 d [15.5-58.3 d]; p = 0.005). Wave 2 patients had longer application of noninvasive ventilation (NIV) prior to ECMO and a higher frequency of barotrauma. Patient age and NIV use were independently associated with increased mortality (odds ratio 1.07 [1.01-1.14]; p = 0.025 and 3.37 [1.12-12.60]; p = 0.043, respectively). QOL and lung function apart from transfer coefficient of carbon monoxide corrected for hemoglobin was similar at follow-up across the waves.

CONCLUSIONS

Most patients with COVID-19 supported on ECMO in both waves survived in the short and longer term. At follow-up patients had similar lung function and QOL across the two waves. This suggests that ECMO has an ongoing role in the management of a carefully selected group of patients with COVID-19.

Bronchiectasis Assessment in Primary Ciliary Dyskinesia: A Non-Invasive Approach Using Forced Oscillation Technique

Primary ciliary dyskinesia (PCD) is an autosomal recessive disorder that results from the dysfunction of motile cilia, which can cause chronic upper and lower respiratory infections leading to bronchiectasis. However, there is a need for additional tools to monitor the progression of bronchiectasis in PCD. The forced oscillation technique (FOT) is an effort-independent lung function test that can be used to evaluate respiratory mechanics. In this retrospective study, we aimed to describe the radiographic findings associated with respiratory impedance (resistance (Rrs) and reactance (Xrs)) measured by FOT in six adult PCD patients and one pediatric with the (RSPH4A (c.921+3_921+6delAAGT (intronic)) founder mutation. We compared the radiographic findings on a high-resolution chest computed tomography (CT) scan with the FOT results. Our findings suggest that respiratory impedance measured by FOT may be a valuable tool for detecting and monitoring the progression of bronchiectasis in PCD patients with the (RSPH4A (c.921+3_921+6delAAGT (intronic)) founder mutation. However, further research is necessary to validate these results and determine the sensitivity and specificity of bronchiectasis monitoring in PCD patients with other genetic mutations.

A study on the prevalence of RLS in OSA and the consequences of co-occurrence

Background

Restless leg syndrome (RLS) is common among patients with obstructive sleep apnoea (OSA) but the prognostic importance of this is not studied. We have called OSA and RLS coexistence as ComOSAR.

Materials and Methods

A prospective observational study was done on patients referred for polysomnography (PSG) with the aims to evaluate 1) the prevalence of RLS in OSA and comparing it with RLS in non-OSA, 2) the prevalence of insomnia, psychiatric, metabolic and cognitive disorders in ComOSAR versus OSA alone, 3) chronic obstructive airway disease (COAD) in ComOSAR versus OSA alone. OSA, RLS and insomnia were diagnosed as per respective guidelines. They were evaluated for psychiatric disorders, metabolic disorders, cognitive disorders and COAD.

Results

Of 326 patients enrolled, 249 were OSA and 77 were non-OSA. 61/249 OSA patients, i.e. 24.4% had comorbid RLS, i.e. ComOSAR. RLS in non-OSA patients was similar (22/77, i.e. 28.5%); P = 0.41. ComOSAR had a significantly higher prevalence of insomnia (26% versus 10.1%; P = 0.016), psychiatric disorders (73.7% versus 48.4%; P = 0.00026) and cognitive deficits (72.1% versus 54.7%, P = 0.016) compared to OSA alone. Metabolic disorders like metabolic syndrome, diabetes mellitus, hypertension and coronary artery disease were also observed in a significantly higher number of patients with ComOSAR versus OSA alone (57% versus 34%; P = 0.0015). COAD was also seen in a significantly higher number of patients with ComOSAR compared to OSA alone (49% versus 19% respectively; P = 0.00001).

Conclusion

It is essential to look for RLS in patients with OSA as it leads to a significantly higher prevalence of insomnia, and cognitive, metabolic and psychiatric disorders. COAD is also more common in ComOSAR compared to OSA alone.

Maximal respiratory pressures: Measurements at functional residual capacity in individuals with different health conditions using a digital manometer

BACKGROUND

Measuring maximal respiratory pressure is a widely used method of investigating the strength of inspiratory and expiratory muscles.

OBJECTIVES

To compare inspiratory pressures obtained at functional residual capacity (FRC) with measures at residual volume (RV), and expiratory pressures obtained at FRC with measures at total lung capacity (TLC) in individuals with different health conditions: post-COVID-19, COPD, idiopathic pulmonary fibrosis (IPF), heart failure (CHF), and stroke; and to compare the mean differences between measurements at FRC and RV/TLC among the groups.

METHODS

Inspiratory and expiratory pressures were obtained randomly at different lung volumes. Mixed factorial analysis of covariance with repeated measures was used to compare measurements at different lung volumes within and among groups.

RESULTS

Seventy-five individuals were included in the final analyses (15 individuals with each health condition). Maximal inspiratory pressures at FRC were lower than RV [mean difference (95% CI): 11.3 (5.8, 16.8); 8.4 (2.3, 14.5); 11.1 (5.5, 16.7); 12.8 (7.1, 18.4); 8.0 (2.6, 13.4) for COVID-19, COPD, IPF, CHF, and stroke, respectively] and maximal expiratory pressures at FRC were lower than TLC [mean difference (95% CI): 51.9 (37.4, 55.5); 60.9 (44.2, 77.7); 62.9 (48.1, 77.8); 58.0 (43.9, 73.8); 57.2 (42.9, 71.6) for COVID-19, COPD, IPF, CHF, and stroke, respectively]. All mean differences were similar among groups.

CONCLUSION

Although inspiratory and expiratory pressures at FRC were lower than measures obtained at RV/TLC for the five groups of health conditions, the mean differences between measurements at different lung volumes were similar among groups, which raises the discussion about the influence of the viscoelastic properties of the lungs on maximal respiratory pressure.

Obesity-related Changes in Diffusing Capacity and Transfer Coefficient of the Lung for Carbon Monoxide and Resulting Patterns of Abnormality across Reference Equations

Rationale: In 2017, an American Thoracic Society/European Respiratory Society Task Force report recommended further research on the effects that body mass index (BMI) has on diffusing capacity of the lung for carbon monoxide (DlCO), the transfer coefficient (Kco), and the alveolar volume (VA). Objectives: Our goals were to 1) quantify the magnitude and direction of change to measured and predicted DlCO values as BMI increases in patients free of cardiopulmonary disease and 2) identify how BMI and obesity-related changes differ by reference set. Methods: Using data from a prospective cohort study of service members free of cardiopulmonary disease, we modeled the effect that BMI has on measured values of DlCO, Kco, and VA, after adjusting for age, sex, hemoglobin (Hgb), and height. We then referenced DlCO, Kco, and VA to normal values using four different reference equations. Results: There were 380 patients with data available for analysis, and 130 had a BMI ⩾ 30 kg/m2 (87.7% class I obesity). After controlling for age, sex, Hgb, and height, increased BMI was significantly associated with Kco (β = 0.09, P < 0.01) and VA (β = -0.15, P < 0.01) but not DlCO. After adjustment for Hgb, for every 5-kg/m2 increase in BMI, the mean increase in percent predicted (PPD) values ranged from 4.2% to 6.5% and from 5.0% to 7.5% for DlCO and Kco, respectively; and the mean decrease in VA PPD was 3.2-4.0%. In the presence of obesity (BMI ⩾ 30 kg/m2), the prevalence of DlCO and Kco abnormalities dropped by 4.1-12.1% and 0.4-16.3%, respectively, across equations, whereas VA abnormalities increased from 7.7% to 9.9%. Eliminating 163 patients with abnormal trans-thoracic echocardiogram (TEE), high-resolution computed tomographic (HRCT) scan, or Hgb altered the magnitude of relationships, but significance was preserved. Conclusions: In an otherwise healthy population with predominantly class I obesity and normal TTE, HRCT scan, and Hgb, we found that Kco and VA were more affected by BMI than DlCO. Increases in PPD values varied across equations and were modest but significant and could change clinical decision making by reducing sensitivity for detecting gas-exchange abnormalities. BMI and obesity had the smallest effect on Global Lung Function Initiative PPD values.

Peri-operative Hemi-diaphragmatic Variations After Brachial Plexus Block Above the Clavicle: A Prospective Observational Study of the Contralateral Side

OBJECTIVE

Hemi-diaphragm palsy after brachial plexus block above the clavicle (BPBAC) occurs frequently, but few patients develop post-operative pulmonary complications (PPC). We hypothesized that contralateral hemidiaphragm function increases after BPBAC. This contralateral function preserves global diaphragmatic function, avoiding PPC in the case of ipsilateral hemi-diaphragm palsy.

METHODS

This prospective observational cohort study included 64 adult patients undergoing shoulder surgery with planned BPBAC (interscalene brachial plexus block and supraclavicular block). The Thickening Fraction (TF) was measured by ultrasound in both hemi-diaphragms, ipsilateral (TF _ipsilateral) and contralateral (TF_{contralateral}) to the BPBAC, before and after the surgery. TF_global is the sum of TF_ipsilateral and TF_{contralateral}. PPC were defined as occurrences of dyspnea, tachypnea, SpO₂ <90% or SpO₂/FiO₂ <315.

RESULTS

TF_{contralateral} increased significantly (an average of 40%) after BPBAC (p = 0.001), and TF_ipsilateral decreased (an average of 72%). After BPBAC, 86% of patients had a decreased TF_ipsilateral and 59% of patients an increased TF_{contralateral} at post-operatively. Only 17% of patients have PPC.

CONCLUSION

After BPBAC, global diaphragm function decreases because of ipsilateral hemi-diaphragm reduction, but less than expected because of increased contralateral hemi-diaphragm function. As a part of diaphragm function, contralateral hemi-diaphragm function must be checked.

ATS/ ERS spirometry quality criteria in real life. Results of two occupational field studies

Spirometry is a widely used test and the American Thoracic Society and the European Respiratory Society (ATS/ERS) provide standardised recommendations. However, detailed information on test quality is often incomplete in publications. In light of the 2005 ATS/ERS recommendations, we investigated the acceptability and repeatability criteria of spirometry performed under occupational field conditions in 242 practicing welders (WELDOX study, median age 41.5 years, all male) and 312 first-year veterinary students (AllergoVet study, median age 20.0 years, 84.3% female). At least three acceptable or usable measurements could be identified for 233 welders and 305 students. The repeatability for welders was 96.1% for the forced expiratory volume in the first second (FEV₁) and 97.0% for forced vital capacity (FVC). The corresponding results for students were 95.7% and 95.4%, respectively. The overall repeatability of test sessions at the 150-mL level was 90.5% (219/242) for welders and 90.1% (281/312) for students. Spirometry can be performed with reliable quality in an occupational field setting.

A Prospective Cohort Study (OUTSTRIP-COVID) on Functional and Spirometry Outcomes in COVID-19 ICU Survivors at 3 Months

Purpose

COVID-19 pandemic resulted in a significant number of critical care admissions secondary to severe pneumonia and acute respiratory distress syndrome. We evaluated the short-, medium- and long-term outcomes of lung function and quality of life in this prospective cohort study and reported the outcomes at 7 weeks and 3 months from discharge from intensive care unit.

Methods

A prospective cohort study of ICU survivors with COVID-19 was conducted from August 2020 to May 2021 to evaluate baseline demographic and clinical variables as well as determine lung function, exercise capacity, and health-related quality of life (HRQOL) using spirometry and 6-minute walk test (6MWT) conducted in accordance with American Thoracic Society standards, and SF-36 (Rand), respectively. SF-36 is a generic 36 question standardized health survey. Descriptive and inferential statistics (alpha = 0.05) were used to analyse the data.

Results

At baseline, 100 participants were enrolled in the study of whom 76 followed up at 3 months. Majority of the patients were male (83%), Asians (84%) and less than 60 years of age (91%). HRQOL showed significant improvement in all domains of SF-36, except in emotional wellbeing. Spirometry variables also showed significant improvement in all variables over time with greatest improvement in percentage predicted Forced expiratory volume 1 (79% vs 88% p < 0.001). 6MWT showed significant improvement in variables of walk distance, dyspnea, and fatigue with greatest improvement in change in oxygen saturation (3% vs 1.44% p < 0.001). Intubation status did not impact the changes in SF-36, spirometry or 6MWT variables.

Conclusion

Our findings suggest that ICU survivors of COVID-19 have significant improvement in their lung function, exercise capacity and HRQOL within 3 months of ICU discharge regardless of intubation status.