Effect of end-inspiratory pause duration on respiratory system compliance calculation in mechanically ventilated dogs with healthy lungs.

OBJECTIVE: To compare respiratory system compliance (CRS), expressed per kilogram of bodyweight (CRSBW), calculated without end-inspiratory pause (EIP) and after three EIP times (0.2, 0.5 and 1 seconds) with that after 3 second EIP (considered the reference EIP for static CRS) and to determine the EIP times that provided CRSBW values in acceptable agreement with static CRSBW during controlled mechanical ventilation (CMV) in anaesthetized dogs. STUDY DESIGN: Prospective, randomized, nonblinded, crossover clinical study. ANIMALS: A group of 24 client-owned dogs with healthy lungs undergoing surgery in lateral recumbency. METHODS: During CMV in dogs undergoing general anaesthesia, five EIPs [0 (no EIP), 0.2, 0.5, 1 and 3 seconds] were consecutively applied in random order. Tidal volume (Vt) was set at 10 mL kg-1 and positive end-expiratory pressure (PEEP) was not applied. Respiratory rate and inspiratory time were established according to each EIP time, setting EIP between 0 and 50% of the inspiratory time. The CRSBW was calculated as [expired Vt/(plateau pressure - PEEP)]/bodyweight and recorded every 15 seconds for 2 minutes after a 5 minute equilibration period with each EIP. One-way anova for repeated measures and the Bland-Altman analysis were used to compare CRSBW and evaluate agreement between EIP times, respectively. RESULTS: The CRSBW was significantly greater as the EIP time increased up to 1 second (p < 0.05). In the Bland-Altman analysis, none of the tested EIPs (0, 0.2, 0.5 and 1 seconds) provided 95% confidence intervals for limits of agreement within the maximum allowed difference considered for acceptable agreement with 3 second EIP. CONCLUSIONS: and clinical relevance An EIP ≤ to 1 second does not provide a CRSBW value in acceptable agreement with static CRSBW in healthy dogs. Besides, the application of an EIP ≤ to 0.5 seconds underestimates the static CRSBW to an increasing extent as the EIP time decreases.

Examination of upper respiratory tracts of Siirt-coloured mohair goats by scanning electron microscopy before and after plastination.

Present study was conducted to determine the changes in the surface structure of the upper respiratory tract of Siirt-coloured mohair goats by the silicone plastination method. Accordingly, the heads of 10 Siirt-coloured mohair goats procured from slaughterhouses were divided into two halves. Half of each head was plastinated. After macro-comparisons were made, the deformations of silicone plastination on the surface were examined by comparing the scanning electron microscope (SEM) findings of both upper respiratory tract tissue samples collected from plastinates and fresh material. When the data from scanning electron microscopy were analysed, cilia, cobblestone patterns, goblet cells and gland ducts on the epithelial surface were identified in areas on the upper respiratory tract. The SEM images of the plastinated tissues showed that the surface structures were degenerated due to the deformation of the surface epithelium. The plastination technique damaged the structures on the surface epithelium. Since the plastination technique and scanning electron microscopy have been studied together for the first time, we believe this would contribute to the scientific literature.

Unraveling the Molecular Regulation of Ferroptosis in Respiratory Diseases.

Ferroptosis, a type of programmed cell death that relies on iron, is distinct in terms of its morphological, biochemical and genetic features. Unlike other forms of cell death, such as autophagy, apoptosis, necrosis, and pyroptosis, ferroptosis is primarily caused by lipid peroxidation. Cells that die due to iron can potentially trigger an immune response which intensifies inflammation and causes severe inflammatory reactions that eventually lead to multiple organ failure. In recent years, ferroptosis has been identified in an increasing number of medical fields, including neurological pathologies, chronic liver diseases and sepsis. Ferroptosis has the potential to cause an inflammatory tempest, with many of the catalysts and pathological indications of respiratory ailments being linked to inflammatory reactions. The growing investigation into ferroptosis in respiratory disorders has also garnered significant interest to better understand the mechanism of ferroptosis in these diseases. In this review, the recent progress in understanding the molecular control of ferroptosis and its mechanism in different respiratory disorders is examined. In addition, this review discusses current challenges and prospects for understanding the link between respiratory diseases and ferroptosis.

Scimitar syndrome with vein stenosis in an infant.

Scimitar syndrome is characterised by right lung hypoplasia and abnormal pulmonary venous return, known as the 'scimitar vein'. We report the case of an infant girl with scimitar syndrome who developed a severe respiratory distress mimicking asthma. Pulmonary hypertension (PH) was diagnosed, attributed to scimitar vein stenosis and a left-to-right shunt. Scimitar vein stenosis, a rare complication of scimitar syndrome, can lead to severe PH, highlighting the importance of prompt management in specialised care centres.

Which reference equation should we use for interpreting spirometry values for First Nations Australians? A cross-sectional study.

OBJECTIVES: To evaluate the suitability of the Global Lung Function Initiative (GLI)-2012 other/mixed and GLI-2022 global reference equations for evaluating the respiratory capacity of First Nations Australians. DESIGN, SETTING: Cross-sectional study; analysis of spirometry data collected by three prospective studies in Queensland, the Northern Territory, and Western Australia between March 2015 and December 2022. PARTICIPANTS: Opportunistically recruited First Nations participants in the Indigenous Respiratory Reference Values study (Queensland, Northern Territory; age, 3-25 years; 18 March 2015 - 24 November 2017), the Healthy Indigenous Lung Function Testing in Adults study (Queensland, Northern Territory; 18 years or older; 14 August 2019 - 15 December 2022) and the Many Healthy Lungs study (Western Australia; five years or older; 10 October 2018 - 7 November 2021). MAIN OUTCOME MEASURES: Goodness of fit to spirometry data for each GLI reference equation, based on mean Z-score and its standard deviation, and proportions of participants with respiratory parameter values within 1.64 Z-scores of the mean value. RESULTS: Acceptable and repeatable forced expiratory volume in the first second (FEV1) values were available for 2700 First Nations participants in the three trials; 1467 were classified as healthy and included in our analysis (1062 children, 405 adults). Their median age was 12 years (interquartile range, 9-19 years; range, 3-91 years), 768 (52%) were female, and 1013 were tested in rural or remote areas (69%). Acceptable and repeatable forced vital capacity (FVC) values were available for 1294 of the healthy participants (88%). The GLI-2012 other/mixed and GLI-2022 global equations provided good fits to the spirometry data; the race-neutral GLI-2022 global equation better accounted for the influence of ageing on FEV1 and FVC, and of height on FVC. Using the GLI-2012 other/mixed reference equation and after adjusting for age, sex, and height, mean FEV1 (estimated difference, -0.34; 95% confidence interval [CI], -0.46 to -0.22) and FVC Z-scores (estimated difference, -0.45; 95% CI, -0.59 to -0.32) were lower for rural or remote than for urban participants, but their mean FEV1/FVC Z-score was higher (estimated difference, 0.14; 95% CI, 0.03-0.25). CONCLUSION: The normal spirometry values of healthy First Nations Australians may be substantially higher than previously reported. Until more spirometry data are available for people in urban areas, the race-neutral GLI-2022 global or the GLI-2012 other/mixed reference equations can be used when assessing the respiratory function of First Nations Australians.

Retinoic Acid-Mediated Control of Energy Metabolism Is Essential for Lung Branching Morphogenesis.

Lung branching morphogenesis relies on intricate epithelial-mesenchymal interactions and signaling networks. Still, the interplay between signaling and energy metabolism in shaping embryonic lung development remains unexplored. Retinoic acid (RA) signaling influences lung proximal-distal patterning and branching morphogenesis, but its role as a metabolic modulator is unknown. Hence, this study investigates how RA signaling affects the metabolic profile of lung branching. We performed ex vivo lung explant culture of embryonic chicken lungs treated with DMSO, 1 µM RA, or 10 µM BMS493. Extracellular metabolite consumption/production was evaluated by using 1H-NMR spectroscopy. Mitochondrial respiration and biogenesis were also analyzed. Proliferation was assessed using an EdU-based assay. The expression of crucial metabolic/signaling components was examined through Western blot, qPCR, and in situ hybridization. RA signaling stimulation redirects glucose towards pyruvate and succinate production rather than to alanine or lactate. Inhibition of RA signaling reduces lung branching, resulting in a cystic-like phenotype while promoting mitochondrial function. Here, RA signaling emerges as a regulator of tissue proliferation and lactate dehydrogenase expression. Furthermore, RA governs fatty acid metabolism through an AMPK-dependent mechanism. These findings underscore RA's pivotal role in shaping lung metabolism during branching morphogenesis, contributing to our understanding of lung development and cystic-related lung disorders.

Effects of COVID-19-targeted non-pharmaceutical interventions on pediatric hospital admissions in North Italian hospitals, 2017 to 2022: a quasi-experimental study interrupted time-series analysis.

Background: The use of Non-Pharmaceutical Interventions (NPIs), such as lockdowns, social distancing and school closures, against the COVID-19 epidemic is debated, particularly for the possible negative effects on vulnerable populations, including children and adolescents. This study therefore aimed to quantify the impact of NPIs on the trend of pediatric hospitalizations during 2 years of pandemic compared to the previous 3 years, also considering two pandemic phases according to the type of adopted NPIs. Methods: This is a multicenter, quasi-experimental before-after study conducted in 12 hospitals of the Emilia-Romagna Region, Northern Italy, with NPI implementation as the intervention event. The 3 years preceding the beginning of NPI implementation (in March 2020) constituted the pre-pandemic phase. The subsequent 2 years were further subdivided into a school closure phase (up to September 2020) and a subsequent mitigation measures phase with less stringent restrictions. School closure was chosen as delimitation as it particularly concerns young people. Interrupted Time Series (ITS) regression analysis was applied to calculate Hospitalization Rate Ratios (HRR) on the diagnostic categories exhibiting the greatest variation. ITS allows the estimation of changes attributable to an intervention, both in terms of immediate (level change) and sustained (slope change) effects, while accounting for pre-intervention secular trends. Results: Overall, in the 60 months of the study there were 84,368 cases. Compared to the pre-pandemic years, statistically significant 35 and 19% decreases in hospitalizations were observed during school closure and in the following mitigation measures phase, respectively. The greatest reduction was recorded for "Respiratory Diseases," whereas the "Mental Disorders" category exhibited a significant increase during mitigation measures. ITS analysis confirms a high reduction of level change during school closure for Respiratory Diseases (HRR 0.19, 95%CI 0.08-0.47) and a similar but smaller significant reduction when mitigation measures were enacted. Level change for Mental Disorders significantly decreased during school closure (HRR 0.50, 95%CI 0.30-0.82) but increased during mitigation measures by 28% (HRR 1.28, 95%CI 0.98-1.69). Conclusion: Our findings provide information on the impact of COVID-19 NPIs which may inform public health policies in future health crises, plan effective control and preventative interventions and target resources where needed.

A case of naltrexone-induced acute eosinophilic pneumonia.

Acute eosinophilic pneumonia (AEP) is a rare cause of acute respiratory failure. Clinical presentations can range from dyspnoea, fever and cough, to rapidly progressive and potentially fulminant respiratory failure. While its exact cause is often unknown, associations with inhalational injuries and exposures to new medications have been described.We report a case of a middle-aged, non-smoking man with a history of alcohol use disorder. He presented with 4 days of shortness of breath that started hours after taking injectable naltrexone (Vivitrol). The patient had rapidly worsening hypoxaemia, necessitating emergent bronchoscopy with transbronchial biopsies and bronchoalveolar lavage which showed 66% eosinophils. The patient was intubated for the procedure and unable to get extubated due to worsening hypoxaemic respiratory failure with high fractional inspired oxygen requirements. Chest radiograph showed worsening lung infiltrates and with a high index of suspicion for AEP, he was started empirically on methylprednisolone. He had rapid improvement in his respiratory status and was extubated on day 5 of admission then discharged on day 8. Histopathological examination confirmed acute/subacute eosinophilic pneumonia. A 3-week post-discharge follow-up chest radiograph confirmed the full resolution of pulmonary infiltrates.Naltrexone-induced AEP is rare, with only six other cases reported in the literature. Careful history taking and prompt evaluation for AEP are important given the potential for rapid progression to acute hypoxic respiratory failure and the excellent response to steroid treatment.

Hyperangulated vs. Macintosh videolaryngoscopy in adults with anticipated difficult airway management: a randomised controlled trial.

BACKGROUND: It is not certain whether the blade geometry of videolaryngoscopes, either a hyperangulated or Macintosh shape, affects glottic view, success rate and/or tracheal intubation time in patients with expected difficult airways. We hypothesised that using a hyperangulated videolaryngoscope blade would visualise a higher percentage of glottic opening compared with a Macintosh videolaryngoscope blade in patients with expected difficult airways. METHODS: We conducted an open-label, patient-blinded, randomised controlled trial in adult patients scheduled to undergo elective ear, nose and throat or oral and maxillofacial surgery, who were anticipated to have a difficult airway. All airway operators were consultant anaesthetists. Patients were allocated randomly to tracheal intubation with either hyperangulated (C-MAC D-BLADE™) or Macintosh videolaryngoscope blades (C-MAC™). The primary outcome was the percentage of glottic opening. First attempt success was designated a key secondary outcome. RESULTS: We assessed 2540 adults scheduled for elective head and neck surgery for eligibility and included 182 patients with expected difficult airways undergoing orotracheal intubation. The percentage of glottic opening visualised, expressed as median (IQR [range]), was 89 (69-99 [0-100])% with hyperangulated videolaryngoscope blades and 54 (9-90 [0-100])% with Macintosh videolaryngoscope blades (p < 0.001). First-line hyperangulated videolaryngoscopy failed in one patient and Macintosh videolaryngoscopy in 12 patients (13%, p = 0.002). First attempt success rate was 97% with hyperangulated videolaryngoscope blades and 67% with Macintosh videolaryngoscope blades (p < 0.001). CONCLUSIONS: Glottic view and first attempt success rate were superior with hyperangulated videolaryngoscope blades compared with Macintosh videolaryngoscope blades when used by experienced anaesthetists in patients with difficult airways.

Exploring the complexities of poultry respiratory microbiota: colonization, composition, and impact on health.

An accurate understanding of the ecology and complexity of the poultry respiratory microbiota is of utmost importance for elucidating the roles of commensal or pathogenic microorganisms in the respiratory tract, as well as their associations with health or disease outcomes in poultry. This comprehensive review delves into the intricate aspects of the poultry respiratory microbiota, focusing on its colonization patterns, composition, and impact on poultry health. Firstly, an updated overview of the current knowledge concerning the composition of the microbiota in the respiratory tract of poultry is provided, as well as the factors that influence the dynamics of community structure and diversity. Additionally, the significant role that the poultry respiratory microbiota plays in economically relevant respiratory pathobiologies that affect poultry is explored. In addition, the challenges encountered when studying the poultry respiratory microbiota are addressed, including the dynamic nature of microbial communities, site-specific variations, the need for standardized protocols, the appropriate sequencing technologies, and the limitations associated with sampling methodology. Furthermore, emerging evidence that suggests bidirectional communication between the gut and respiratory microbiota in poultry is described, where disturbances in one microbiota can impact the other. Understanding this intricate cross talk holds the potential to provide valuable insights for enhancing poultry health and disease control. It becomes evident that gaining a comprehensive understanding of the multifaceted roles of the poultry respiratory microbiota, as presented in this review, is crucial for optimizing poultry health management and improving overall outcomes in poultry production.

Lower respiratory tract infections in children with congenital lung abnormalities.

OBJECTIVE: We aimed to determine if the incidence of lower respiratory tract infections (LRTI) among children with asymptomatic, observationally managed congenital lung abnormalities (CLA) differed from that of symptomatic patients who underwent surgery. Second, we sought to compare the pre- and post-resection incidence of LRTI in patients who underwent surgery. METHODS: This retrospective cohort study included patients born between 1999 and 2021 with CLA confirmed by CT scan who were enrolled in a prospective longitudinal follow-up program. The LRTI incidence rates at 1, 2, 5, 8, and 12 years were compared between surgically and observationally managed patients using incidence rate ratios (IRR). Differences in pre- and post-resection LRTI incidence rates among patients who underwent CLA-related surgery were assessed through IRR. RESULTS: Among 217 included patients, 81 (37%) had undergone surgery and 136 (63%) had been observationally managed. The LRTI incidence rates did not significantly differ at any follow-up moment between the surgical and observational groups. Among the children who underwent CLA-related surgery, the pre-resection LRTI incidence rates were significantly higher than the post-resection LRTI incidence rates (IRR of 3.57, 95% confidence interval: [2.00; 6.33], p < .001). CONCLUSION: We could not demonstrate differences in LRTI incidence throughout childhood between patients with surgically and observationally managed CLA. We recommend discussing cases of LRTI in patients with CLA in a multidisciplinary setting, using additional diagnostics such as chest X-ray to screen for CLA involvement, enabling a well-considered decision on surgical resection of the lesion.

Health Effects of Ionizing Radiation on the Human Body.

Radioactivity is a process in which the nuclei of unstable atoms spontaneously decay, producing other nuclei and releasing energy in the form of ionizing radiation in the form of alpha (α) and beta (ß) particles as well as the emission of gamma (γ) electromagnetic waves. People may be exposed to radiation in various forms, as casualties of nuclear accidents, workers in power plants, or while working and using different radiation sources in medicine and health care. Acute radiation syndrome (ARS) occurs in subjects exposed to a very high dose of radiation in a very short period of time. Each form of radiation has a unique pathophysiological effect. Unfortunately, higher organisms-human beings-in the course of evolution have not acquired receptors for the direct "capture" of radiation energy, which is transferred at the level of DNA, cells, tissues, and organs. Radiation in biological systems depends on the amount of absorbed energy and its spatial distribution, particularly depending on the linear energy transfer (LET). Photon radiation with low LET leads to homogeneous energy deposition in the entire tissue volume. On the other hand, radiation with a high LET produces a fast Bragg peak, which generates a low input dose, whereby the penetration depth into the tissue increases with the radiation energy. The consequences are mutations, apoptosis, the development of cancer, and cell death. The most sensitive cells are those that divide intensively-bone marrow cells, digestive tract cells, reproductive cells, and skin cells. The health care system and the public should raise awareness of the consequences of ionizing radiation. Therefore, our aim is to identify the consequences of ARS taking into account radiation damage to the respiratory system, nervous system, hematopoietic system, gastrointestinal tract, and skin.

Protocol for the "magnitude of cigarette substitution after initiation of e-cigarettes and its impact on biomarkers of exposure and potential harm in dual users" (MAGNIFICAT) study.

Introduction: Many smokers who use e-cigarettes (ECs) to quit continue smoking alongside vaping. The impact on health among individuals who simultaneously smoke conventional cigarettes (CCs) and use ECs remains unclear. The varying patterns of dual use present differing levels of overall toxin exposure and relative risks concerning smoking-related diseases. Understanding these complexities is vital to assessing the implications for human health. Objective: Herein we describe a protocol designed to analyze the impact of different level of substituting CCs with ECs on exposure to toxicants. We'll use biomarkers to measure this exposure and assess harm reduction in dual users through clinical endpoints, harm-related biomarkers, and behavioral correlations. We expect to observe progressive changes with varying patterns of dual use. Methods and analyses: For this purpose, we planned to recruit a group of 250 smokers who will be asked to reduce their CC consumption by adopting ECs (intervention group). A separate group of 50 smokers will continue to smoke CC (reference group). Study groups will be followed up for 6 months during which biospecimens will be collected for biomarker analyses, and clinical endpoints will be assessed. The trial is structured to characterize subjects' usage patterns over time using robust biomarkers of exposure and a standardized mobile phone application to facilitate the precise categorization of dual users along the risk continuum based on their usage behaviors. Subject recruitment will start in February 2024 and enrolment is expected to be completed by August 2024. Results will be reported early in 2025. Study findings may provide valuable insights into health benefits or risks associated with varying patterns of dual use. Ethics and dissemination: The study protocol and informed consent forms will be approved by the local Ethical Review Boards. Study results will be disseminated through articles published in reputable, peer-reviewed, open access, scientific journals, presentations at conferences, and the University website.

Intertemporal Improvement in Physicians' Perceptions of the Short-Term Adverse Outcomes of Neonatal Pain: Results of a Two-Time-Point National Survey.

Pain in early life may seriously impact neonatal outcomes. This study aimed to evaluate whether the perceptions of physicians working in neonatal intensive care units (NICUs) of the short-term adverse outcomes associated with neonatal pain have changed over a 20-year period. Self-administered questionnaires were distributed to 117 and 145 neonatologists, pediatricians, and fellows working in level III NICUs in 2000 (T1) and 2019 (T2), respectively. The questionnaire consisted of four domains, including the central nervous, cardiovascular, and respiratory systems, as well as "other systems" (metabolic/endocrine system, growth, and general condition), with 21 total items overall. Although the proportion of positive (correct) responses to the total and system-specific domain scores was significantly higher at T2 than T1, the knowledge of certain short-term adverse outcomes was suboptimal even at T2. Adjustment for cofactors confirmed the independent association of the survey time-point with the total and system-specific domain scores. Moreover, NICU type was an independent significant factor associated with the adjusted total and central nervous system scores, while young doctors had a better knowledge of adverse cardiovascular effects. Conclusions: The perceptions of NICU physicians concerning the short-term outcomes associated with neonatal pain have significantly improved over the past 20 years, although remaining knowledge gaps mandate ongoing efforts to achieve an improvement in neonatal care.

Non-tuberculous mycobacterial pulmonary infection presenting in a patient with unilateral pulmonary artery agenesis.

People who have structural or developmental lung disease are more likely to develop non-tuberculous mycobacterial infections. We present the case of a young man in his 30s who had unilateral pulmonary artery agenesis on the right side and presented with a 6-month history of productive cough and fever. His CT scan showed nodular and cavitating lesions on the right side, and sputum analysis confirmed infection with Mycobacterium chimaera He had to undergo modifications in his treatment, including a change from rifampicin to rifabutin due to drug interactions and his amikacin had to be stopped due to signs of vestibular toxicity. Using a multidisciplinary approach, we were able to formulate an appropriate drug regimen for him, and he is now under regular follow-up with infectious diseases and respiratory medicine.

Role of physical therapy intervention in acute disseminated encephalomyelitis.

We reported a case of a school-going child, diagnosed with acute disseminated encephalomyelitis (ADEM) who presented with symptoms such as high fever, acute hemiplegia and ataxia and was referred for physiotherapeutic intervention. This case report aims to document the assessment and management of ADEM from the intensive care unit to the home setting by physical therapy. Also, the child developed ventilator-associated pneumonia and a right lower motor neuron facial injury for which the child was referred to paediatric physical therapy. Since then, continuing for 8 months has helped the child to be independent in all aspects of mobility with no complaints. The child showed improvement in WeeFIM scores and Sunnybrook facial grading after 99 sessions of intensive physical therapy for approximately 83 hours along with the home programme. It has been proven an efficient treatment method along with other medical lines of treatment for neurological impairment associated with ADEM.

Acute primary CMV infection complicated by pneumonitis and ITP in young immunocompetent woman in a regional Queensland Hospital.

We present the first published case of simultaneous pneumonitis and immune thrombocytopenic purpura secondary to primary cytomegalovirus (CMV) infection in an immunocompetent patient. Treatment with oral valganciclovir for 2 weeks successfully led to complete clinical recovery. CMV is traditionally associated with infection in immunocompromised patients and neonates; however, evidence of severe CMV infections in immunocompetent hosts is emerging. It is important to highlight the broad range of clinical presentations of CMV infections to prevent diagnostic delay and associated morbidity and expense.

Anomalous systemic arterial supply to the basal segment of the lung presenting with haemoptysis in the third trimester of pregnancy.

Anomalous systemic arterial supply to the basal segment of the lung (ABLL) is a rare cause of haemoptysis. ABLL may be complicated by massive haemoptysis, heart failure due to left-to-right shunt and infection. We describe a case of this condition presenting in the third trimester of pregnancy. Computed tomography chest angiogram confirmed the diagnosis. A multidisciplinary approach was necessary to determine treatment, which ultimately consisted of elective caesarean section at 36 weeks and 4 days' gestation, followed by transarterial embolisation 9 days postpartum.

The application of impulse oscillometry system based on machine learning algorithm in the diagnosis of chronic obstructive pulmonary disease.

OBJECTIVE: Diagnosing chronic obstructive pulmonary disease (COPD) using Impulse Oscillometry (IOS) is challenging due to the high level of clinical expertise it demands from doctors , which limits the clinical application of IOS in screening. The primary aim of this study is to develop a COPD diagnostic model based on machine learning algorithms using IOS test results. Approach:Feature selection was conducted to identify the optimal subset of features from the original feature set, which significantly enhanced the classifier's performance. Additionally, secondary features area of reactance (AX) were derived from the original features based on clinical theory, further enhancing the performance of the classifier. The performance of the model was analyzed and validated using various classifiers and hyperparameter settings to identify the optimal classifier. We collected 528 clinical data examples from the China-Japan Friendship Hospital for training and validating the model. Main results:The proposed model achieved reasonably accurate diagnostic results in the clinical data (accuracy=0.920, specificity=0.941, precision=0.875, recall=0.875). Significance:The results of this study demonstrate that the proposed classifier model, feature selection method, and derived secondary feature AX provide significant auxiliary support in reducing the requirement for clinical experience in COPD diagnosis using IOS. .