Pulmonary Function Research Articles

The Association Between Patient-Level Factors and Physical Function in Lung Transplant Recipients

Purpose: Despite the dramatic improvement in pulmonary function after lung transplantation, lung transplant recipients often have reduced physical function. The purpose of this study was to investigate the associations between physical function and a wide range of patient-level factors among lung transplant recipients to allow researchers and health care providers to identify and better understand contributors to poor physical function. Methods: A cross-sectional study of lung transplant recipients enrolled in Lung Transplant Go, a randomized, controlled trial evaluating the efficacy of a telerehabilitation behavioral exercise intervention on physical function. Data were collected at the time of study enrollment for physical function using the 30-second sit-to-stand (STS-30) test, and patient-level factors included discharge destination, time since transplant, hospital length of stay, participation in exercise program outside the study, comorbidities, psychological distress, and symptoms. Regression analysis was performed to identify the association between physical function and patient-level factors. Results: A total of 72 lung transplant recipients with a mean age of 56 years (13), 58% male and 88% White, completed the STS-30 test. The bivariate analysis identified factors associated with STS-30 performance, which are age, marital status, time since transplant, Questionnaire for Lung Transplant Patients' activity intolerance subscale, and psychological distress. Factors that significantly predicted STS-30 performance using the regression analysis were age, time since transplant, and psychological distress (P < .05). Conclusions: Age, time since lung transplantation, and psychological distress significantly predicted poor physical function. Interventions to prevent poor physical function after lung transplantation should consider these factors. Research is needed to better understand patient-level factors on other physical function measures.

Pulmonary Rehabilitation Effect on Physiological and Biochemical Parameters Occupationally Exposed to Silica Workers: A Quasi-Experimental Study

Occupational workers are at health risk due to exposure to silica dust, which is present in the construction and manufacturing sectors, masonry works, as well in mining sectors. Silicosis is a type of pulmonary fibrosis, a lung disease caused by breathing in tiny bits of silica, a common mineral found in sand, quartz, and many other types of rock. Materials and methods: Occupational workers who are exposed to silica and working in cement factories. Who fulfills the inclusion criteria, the sample size was (n = 160) divided into a control group (n =8 0) and an experimental group (n = 80). A pretest was conducted on to control and experimental groups. Pulmonary parameters, baseline clinical variables, spirometry to check pulmonary function, 6-MWT stress tolerance test, Hemoglobin (HB), Erythrocyte Sedimentation Rate (ESR), Random Blood Sugar (RBS) blood investigations, pranayama (yoga), and nutritional education were done for the experimental group. Supervised pulmonary rehabilitation was carried out, and the posttest was done after 12, 18, and 24 weeks. The results were analyzed by descriptive and inferential statistical methods using the SPSS statistical package (Systat Software Inc., San Jose, USA). Conclusion: Pulmonary rehabilitation (pranayama and nutritional education) showed significant improvement in lung capacity and pulmonary functions, and improved quality of life showed statistical significance (P < 0.001).

Pulmonary Function In Non-hospitalized Covid-19 Survivors

Pulmonary Function In Non-hospitalized Covid-19 Survivors

Diagnosis of renal tumors in Birt-Hogg-Dube syndrome: Clinical presentation and risk factors in a single-center retrospective cohort

BackgroundBirt-Hogg-Dube (BHD) syndrome is a rare genetic condition associated with the development of renal tumors. This study aims to determine typical age ranges for detecting renal abnormalities, risk factors for tumor development, and long-term outcomes based on current surveillance strategies.MethodsA single-center multi-site retrospective cohort study was performed on all patients with BHD diagnosed from 2000 to 2023. Baseline demographics, pulmonary function, laboratory, radiologic, and histopathologic findings were collected. Logistic regression was used to assess predictor variables for the development of renal tumors with survival analysis evaluated from the date of BHD diagnosis to date of death or last known follow-up.ResultsThe study included 149 patients with BHD, 39 (26%) with diagnosed renal tumors, of which 28 had histopathologic confirmation. Mean age at renal tumor detection was 53.61 years. Older age and male sex were predictive of renal tumor development ((odds ratio 1.05; 95% CI, 1.01–1.08, P = 0.002) and (odds ratio 2.59; 95% CI, 1.17–5.73, P = 0.02), respectively). Time to all-cause mortality appeared shorter in those with renal tumors (Log-rank P = 0.02), though no deaths were from cancer or cancer-related complications.ConclusionsCurrent screening protocols for renal tumors in BHD suggest the most common presenting age range for presentation is late 40s to early 50s, with older age and male sex as risk factors for tumor development.

Fatigue in severe pediatric asthma patients: Results of the PANDA study.

Fatigue is a commonly reported clinical symptom, yet research on fatigue in children with severe asthma is missing. We aimed to explore the extent of fatigue in severe pediatric asthma and identify associated factors. This study was conducted within the Pediatric Asthma Non-Invasive Diagnostic Approaches (PANDA), an observational cohort of 6- to 17-year-old Dutch children with severe asthma. The Pediatric Quality of Life Inventory Multidimensional Fatigue Scale (PedsQL™-MFS) was used to measure self-reported fatigue. Fatigue levels were compared with a general pediatric Dutch population using linear regression, and quantifying the prevalence of "fatigued" (-2 < Standard deviations [SD] ≤ -1) and "severely fatigued" (SD ≤ -2) children. Secondly, we performed linear regression analyses to explore whether fatigue levels were independently associated with asthma attacks, comorbidities, medication, pulmonary function, symptom control, and asthma-related quality of life (QoL). Severe pediatric asthma patients (n = 78, mean age 11.8 ± 3.1 years) reported significantly more fatigue than Dutch peers (n = 328, mean age 11.8 ± 3.2 years) mean difference in z-score: -0.68; 95%CI -0.96, -0.40. In the severe asthma group, 28.2% scored as "fatigued" and 15.4% as "severely fatigued," compared with 14.0% and 3.4% in the general population. In pediatric asthma patients, asthma-related QoL (β = 0.77, p < .01, ΔR2 = .43), symptom control (β = 0.56, p < .01, ΔR2 = .24) and a dysfunctional breathing pattern (β = -0.36, p < .01, ΔR2 = .12) were most strongly associated with fatigue scores. Fatigue is a common symptom in children with severe asthma and is associated with multiple clinical factors and patient-reported outcomes. It should be considered as an important treatment target.

Effects of 8-weeks Surf Skateboard training on physical fitness in young people

BackgroundSurf skateboards have grown in popularity among young people in recent years. However, no research studies have analyzed the effect of surf skateboarding on physical fitness. ObjectiveThe purpose of this study was to determine the effects of 8-week surf skateboard training on physical fitness in young adults. MethodsTwenty-two young people, ages 18–24 years were randomly assigned into two groups: a control (CON; n = 11) and surf skateboarding (SSK; n = 11) group. The surf skateboard training group received an eight-week intervention consisting of three 60-minute (min) sessions per week, while the control group continued with their normal daily lives. Physical fitness was assessed before and after the intervention through a battery of tests that included body composition, cardiorespiratory fitness, muscular strength and endurance, flexibility, and balance. ResultsThe results showed that the SSK group demonstrated significant (p < 0.05) improvements in maximum voluntary ventilation, back and leg strength, lower body muscular endurance by the sit-to-stand tests, and balance in all direction compared with the pre-test and the CON group. In addition, the SSK group showed significantly (p < 0.05) decreased body weight, body mass index, percent body fat, and resting heart rate, while increased maximum oxygen consumption, pulmonary function, respiratory muscle strength, upper body muscular endurance by the sit-up test and flexibility compared with the pre-test. ConclusionThe findings suggest that surf skateboard training have an effective physical activity intervention to improve body composition, cardiorespiratory fitness, muscular strength and endurance, flexibility, and balance in young people.

Diaphragm-sparing efficacy of subparaneural upper trunk block for arthroscopic shoulder surgery: A randomised controlled trial.

Inter-scalene block (ISB) is associated with an inevitable risk of hemi-diaphragmatic paresis (HDP). To reduce the risk of HDP, an upper trunk block (UTB) has been proposed at the brachial plexus division level. We hypothesised that UTB would be associated with a lower incidence of HDP than ISB while providing sufficient analgesia following arthroscopic shoulder surgery. Randomised controlled trial. A tertiary teaching hospital. Seventy patients aged 20 to 80 years undergoing arthroscopic rotator cuff repair. Ultrasound-guided ISB or UTB was performed with 5 ml 0.75% ropivacaine. The primary outcome was the incidence of complete HDP, assessed by diaphragm excursion using ultrasound, defined as a decrease to 25% or less of baseline or occurrence of paradoxical movement. Postoperative pulmonary function change, pain scores, opioid consumption and pain-related outcomes were the secondary outcomes. The UTB group had a significantly lower incidence of complete HDP than the ISB group [5.9% (2/34) vs. 41.7% (15/36); absolute difference, 35.8%; 95% confidence interval (CI), 17.8 to 53.7%; P < 0.001]. The postblockade decline in pulmonary function was more pronounced in the ISB group than that in the UTB group. The pain score at 1 h postoperatively was not significantly different between the groups (ISB vs. UTB group: median 0 vs. 1; median difference, -1; 95% CI, -2 to 0.5). No significant difference was observed in any other secondary outcomes. UTB was associated with a lower incidence of HDP compared with ISB while providing excellent analgesia in arthroscopic shoulder surgery. Clinical Trial Registry of Korea ( https://cris.nih.go.kr ) identifier: KCT0007002. Chungnam National University Hospital Institutional Review Board No. 2021-12-069.

Loss of Nr4a1 ameliorates endothelial cell injury and vascular leakage in lung transplantation from circulatory-death donor

BackgroundIschemia-reperfusion injury (IRI) stands as a major trigger for primary graft dysfunction (PGD) in lung transplantation (LTx). Especially in LTx from donation after cardiac death (DCD), effective control of IRI following warm ischemia (WIRI) is crucial to prevent PGD. This study aimed to identify the key factors affecting WIRI in LTx from DCD. MethodsPreviously reported RNA-sequencing dataset of lung WIRI was reanalyzed to identify nuclear receptor subfamily 4 group A member 1 (NR4A1) as the immediate early gene for WIRI. Dynamics of NR4A1 expression were verified using a mouse hilar clamp model. To investigate the role of NR4A1 in WIRI, a mouse model of LTx from DCD was established using Nr4a1 knockout (Nr4a1-/-) mice. ResultsNR4A1 was located around vascular cells, and its protein levels in the lungs increased rapidly and transiently during WIRI. LTｘ from Nr4a1-/- donors significantly improved pulmonary graft function compared to wild-type donors (P < 0.001). Histological analysis showed decreased microvascular endothelial cell death (P = 0.007), neutrophil infiltration (P < 0.001), and albumin leakage (P < 0.001). Evans blue permeability assay demonstrated maintained pulmonary microvascular barrier integrity in grafts from Nr4a1-/- donors, correlating with diminished pulmonary edema (P < 0.001). However, NR4A1 did not significantly affect the inflammatory response during WIRI, and IRI was not suppressed when a wild-type donor lung was transplanted into the Nr4a1-/- recipient. ConclusionsDonor NR4A1 plays a specialized role in the positive regulation of endothelial cell injury and microvascular hyperpermeability. These findings demonstrate the potential of targeting NR4A1 interventions to alleviate PGD and improve outcomes in LTx from DCD.

Effect of the Antibody-mediated Immune Responses on COPD, Asthma, and Lung Function: A Mendelian Randomization Study

IntroductionThe precise cause of antibody-mediated immune responses on chronic obstructive pulmonary disease (COPD), asthma, and lung function remains unclear. We characterized the relationship between antibody-mediated immune responses to COPD, asthma, and lung function, ultimately achieve the prevention or treatment. MethodsWe obtained summary data from published genome-wide association studies, including antibody-mediated immune responses, COPD, asthma, forced expiratory volume in the first second (FEV1), forced expiratory volume (FVC), and FEV1/FVC. Bidirectional two-sample mendelian randomization (MR) analysis was used to assess causal relationships of antibody-mediated immune responses, COPD, asthma, FEV1, FVC, and FEV1/FVC. ResultsA total of 20 antibody-mediated immune responses were identified have a significant causal effect on COPD, asthma, FEV1, and FVC, with six exhibiting reverse causality. Importantly, the results of the five MR analyses were almost identical with respect to the causal effect of anti-polyomavirus 2 IgG seropositivity and varicella zoster virus glycoprotein E and I antibody levels on the risk of COPD, asthma, FEV1, and FVC. ConclusionsThis study contributes to existing knowledge by investigating the causal relationship between antibody-mediated immune responses and respiratory conditions, including COPD, asthma, and lung function, using a two-sample MR design. The key findings can aid in identifying individuals at risk of these conditions and facilitate early prevention and diagnosis.

The Lymphatic Highway: How Lymphatics Drive Lung Health and Disease.

The pulmonary lymphatic system has emerged as a critical regulator of lung homeostasis and a key contributor to the pathogenesis of respiratory diseases. As the primary conduit responsible for maintaining fluid balance and facilitating immune cell trafficking, the integrity of lymphatic vessels is essential for preserving normal pulmonary structure and function. Lymphatic abnormalities manifest across a broad spectrum of pulmonary disorders, underscoring their significance in respiratory health and disease. This review provides an overview of pulmonary lymphatic biology and delves into the involvement of lymphatics in four major lung diseases: chronic obstructive pulmonary disease (COPD), idiopathic pulmonary fibrosis (IPF), asthma, and lung transplant rejection. We examine how lymphatic abnormalities manifest in each of these conditions and investigate the mechanisms through which lymphatic remodeling and dysfunction contribute to disease progression. Furthermore, we explore the therapeutic potential of targeting the lymphatic system to ameliorate these debilitating respiratory conditions. Despite the current knowledge, several crucial questions remain unanswered, such as the spatial and temporal dynamics of lymphatic changes, the molecular crosstalk between lymphatics and the lung microenvironment, and the distinction between protective versus detrimental lymphatic phenotypes. Unraveling these mysteries holds the promise of identifying novel molecular regulators, characterizing lymphatic endothelial phenotypes, and uncovering bioactive mediators. By harnessing this knowledge, we can pave the way for the development of innovative disease-modifying therapies targeting the lymphatic highway in lung disorders.

Baseline forced oscillation technique predicting lack of exacerbations in adult with asthma: A 12-month prospective

BackgroundThe forced oscillation technique (FOT) is a minimally invasive test to evaluate asthma during resting ventilation. However, its role in longitudinal assessments, such as clinical remission, remains unclear. ObjectiveTo longitudinally assess asthma clinical remission and identify parameters that predict clinical remission at 12 months from baseline FOT. MethodsAdult patients with asthma at our university hospital between April 2022 and May 2023 were enrolled in this prospective observational study. They were evaluated for 12 months after enrollment to determine whether they met the following clinical remission criteria: asthma control test score of more than or equal to 20 at enrollment and 12 months, no asthma exacerbations for 12 months, and no regular oral corticosteroid use during the 12 months. FOT parameters at enrollment were analyzed for associations with clinical remission. ResultsA total of 94 patients with asthma completed the study and were categorized into clinical and nonclinical remission groups. Comparison of pulmonary function tests, including the FOT, between the 2 groups revealed significant differences in resistance at 5 Hz and resistance at 20 Hz (R20) but not in forced expiratory volume in 1 second. Multivariate logistic regression analysis revealed that R20 was associated with clinical remission, with adjusted odds ratios of 0.32 (95% CI: 0.12-0.91, P = .033) for R20. ConclusionR20 can be a useful predictor of future exacerbations in patients with asthma. These findings may assist in evaluating adult patients with asthma and normal forced expiratory volume in 1 second.

Clinical outcomes in ventilator-associated pneumonia patients with and without chronic obstructive pulmonary disease: A retrospective observational study.

Chronic obstructive pulmonary disease (COPD) is the third leading cause of death worldwide. Critically ill patients with COPD exacerbations may require invasive mechanical ventilation (IMV). Ventilator-associated pneumonia (VAP) commonly occurs in the intensive care unit (ICU) and is usually associated with high mortality. Current studies on the relationship between COPD and VAP are limited. This work compares the etiology and clinical outcomes of VAP between patients with and without COPD in Taiwan. This retrospective observational study was conducted at the Chiayi Chang Gung Memorial Hospital. Patients with VAP were enrolled between January 2015 and December 2019. The COPD diagnosis was based on post-bronchodilator pulmonary function tests. We compared the bacterial etiology, ICU and hospital stay length, IMV duration, and mortality. A total of 175 patients with VAP were enrolled, 44% of whom presented pre-existing COPD. The disease severity on the day of admission was similar in both groups. Microorganisms were identified in 83 (47%) patients, with Pseudomonas aeruginosa, Acinetobacter spp., and Klebsiella pneumoniae being the most common pathogens. The proportion of multi-drug resistant isolates showed no significant differences between groups. Most patients underwent antibiotic treatment before VAP onset. The length of ICU and hospital stays and IMV duration after VAP onset were similar between groups, as well as ICU mortality, in-hospital mortality and 14-day mortality. Our study revealed that COPD was not associated with worse clinical outcomes in patients with VAP. No significant differences in bacterial etiology were observed between the two groups.

EP.08F.01 Predicting Radiation Pneumonitis with Baseline Pulmonary Function Tests in Patients with Locally Advanced Non-Small Cell Lung Cancer (NSCLC)

EP.08F.01 Predicting Radiation Pneumonitis with Baseline Pulmonary Function Tests in Patients with Locally Advanced Non-Small Cell Lung Cancer (NSCLC)

Impact of post-pulmonary tuberculosis sequelae and its management in a tertiary care facility in South India

BackgroundPost-pulmonary Tuberculosis (PTB) sequelae are chest alterations caused by pulmonary tuberculosis problems, even after treatment and infection elimination. These alterations can cause pulmonary dysfunction, ranging from mild irregularities to acute dyspnea, increasing the risk of respiratory-related deaths. Current research aims to investigate the type, severity, clinical management, and impact on quality of life in affected individuals. Materials and methodsA prospective observational study with 66 patients was carried out in a South Indian tertiary care facility. We gathered sociodemographic and clinical data from the patients. Imaging investigations (chest X-ray, CT scans) and pulmonary function test reports (Spirometry) were used to assess the post-pulmonary TB sequelae. The patient's quality of life was evaluated using the WHOQoL-BREF questionnaire. ResultsOut of 66 patients, 66.7% were men, and the average age was 57.2 years. According to radiological analysis, most patients had airway difficulties (38%), followed by parenchymal problems (36.3%). Obstruction was the most typical abnormality identified (81.9%). Bronchodilators, LABA + ICS, SABA, leukotriene antagonists, antibiotics, and other fixed medications treat post-PTB sequelae. Substantial impairment was observed in quality of life. ConclusionPatients who have had pulmonary TB are prone to post-TB respiratory symptoms and sequelae. The quality of life noticeably declined. This study's findings underscore the importance of robust, evidence-based guidelines and practical implementation techniques for managing post-pulmonary TB.

Detection and management of autoimmune disease-associated interstitial lung diseases.

Interstitial lung disease (ILD) causes significant morbidity and mortality in patients with systemic autoimmune rheumatic diseases. Patients at high risk of ILD should be screened using high-resolution CT (HRCT), but there is no consensus as to which risk factors-or combination of risk factors-should prompt referral for HRCT. The course of autoimmune disease-associated ILD is highly variable, and it may not mirror the activity of the underlying autoimmune disease. Patients require close monitoring with periodic pulmonary function testing and symptom assessment and with repeat HRCT considered based on clinical assessment. The relevance of clinical and radiologic signs of progression-and their implications for management-ideally should be discussed by a multidisciplinary team. Management of autoimmune disease-associated ILD may involve immunosuppressant and/or antifibrotic therapy in addition to supportive care. It is important that treatment decisions be individualized to the needs and wishes of the patient. Regular follow-up is important to monitor disease progression and manage the adverse effects related to treatment.

Low-Dose Whole-Chest Dynamic CT for the Assessment of Large Airway Collapsibility in Patients with Suspected Tracheobronchial Instability.

Purpose To quantify tracheal collapsibility using low-dose four-dimensional (4D) CT and to compare visual and quantitative 4D CT-based assessments with assessments from paired inspiratory-expiratory CT, bronchoscopy, and spirometry. Materials and Methods The authors retrospectively analyzed 4D CT examinations (January 2016-December 2022) during shallow respiration in 52 patients (mean age, 66 years ± 12 [SD]; 27 female, 25 male), including 32 patients with chronic obstructive pulmonary disease (mean forced expiratory volume in 1 second percentage predicted [FEV1%], 50% ± 27), with suspected tracheal collapse. Paired CT data were available for 27 patients and bronchoscopy data for 46 patients. Images were reviewed by two radiologists in consensus, classifying patients into three groups: 50% or greater tracheal collapsibility, less than 50% collapsibility, or fixed stenosis. Changes in minimal tracheal lumen area, tracheal volume, and lung volume from inspiration to expiration were quantified using YACTA software. Tracheal collapsibility between groups was compared employing one-way analysis of variance (ANOVA). For related samples within one group, ANOVA with repeated measures was used. Spearman rank order correlation coefficient was calculated for collapsibility versus pulmonary function tests. Results At 4D CT, 25 of 52 (48%) patients had tracheal collapsibility of 50% or greater, 20 of 52 (38%) less than 50%, and seven of 52 (13%) had fixed stenosis. Visual assessment of 4D CT detected more patients with collapsibility of 50% or greater than paired CT, and concordance was 41% (P < .001). 4D CT helped identify more patients with tracheal collapsibility of 50% or greater than did bronchoscopy, and concordance was 74% (P = .39). Mean collapsibility of tracheal lumen area and volume at 4D CT were higher for 50% or greater visually assessed collapsibility (area: 53% ± 9 and lumen: 52% ± 10) compared with the less than 50% group (27% ± 9 and 26% ± 6, respectively) (P < .001), whereas both tracheal area and volume were stable for the fixed stenosis group (area: 16% ± 12 and lumen: 21% ± 11). Collapsibility of tracheal lumen area and volume did not correlate with FEV1% (rs = -0.002 to 0.01, P = .99-.96). Conclusion The study demonstrated that 4D CT is feasible and potentially more sensitive than paired CT for central airway collapse. Expectedly, FEV1% was not correlated with severity of tracheal collapsibility. Keywords: CT-Quantitative, Tracheobronchial Tree, Chronic Obstructive Pulmonary Disease, Imaging Postprocessing, Thorax Supplemental material is available for this article. © RSNA, 2024.

Identification, course, and management ofprogressive pulmonary fibrosis.

The term "progressive pulmonary fibrosis" or "PPF" is generally used to describe progressive lung fibrosis in an individual with an interstitial lung disease (ILD) other than idiopathic pulmonary fibrosis (IPF). Several sets of criteria have been proposed for the identification of PPF, most of which are based on a combination of a decline in forced vital capacity, worsening of respiratory symptoms, and increase in the extent of fibrosis on radiology. Although some risk factors for faster progression of fibrosing ILD have been identified, it remains challenging to predict which individuals will develop PPF. Close monitoring, including regular pulmonary function tests, is required to detect the earliest signs of worsening disease. PPF is associated with high rates of hospitalization and death. Management of PPF requires a multidisciplinary and multimodal approach, including pharmacological therapy and supportive care. Discussions about palliative care should begin at an early stage, individualized to the needs of the patient.

Evaluation Of Spirometric Parameters In Patients With Type 2 Diabetes Mellitus - A Cross-Sectional Study In A Tertiary Care Hospital In North East India

Introduction: Diabetes mellitus is a common metabolic disorder that affects different organ systems in our body. Pulmonary complication of diabetes is not well characterized because of scarcity of data. Purpose of the present study was to evaluate the lung functions among the patients with Type2 DM. Materials and method: To evaluate the lung functions 85 type 2 diabetic patients were included in the study. Informed consent was obtained from the study participants. After taking a brief history, spirometry was performed among the recruited patients. The data were recorded in Microsoft excel and analyzed using SPSS software. Result: The quantitative data were expressed in terms of mean and standard deviation. Lung function parameters FVC, FEV1, and MVV were (2.05±0.66) Liters, (2.05±0.66) Liters and (52.22±18.17) L/min respectively. FEV1/FVC ratio was 73.74±13.36. FEV1 had a significant (p value: 0.002) negative correlation with duration of diabetes (r value: -0.330). Conclusion: The spirometric parameters FVC, FEV1 and MVV were found to be reduced among the study participants, whereas FEV1/FVC ratio was normal. These findings suggest presence of deterioration of lung functions among type 2 diabetic patients which is of restrictive type. Our study also showed that deterioration of lung function is more as the duration of disease increases. Therefore, the patients with type2 diabetes are needed to undergo pulmonary function testing periodically

Clinical Characteristics and Outcomes of Interstitial Lung Disease Patients with Acute Respiratory Failure Admitted to the ICU

Abstract Background: Acute respiratory failure is a dreaded complication of interstitial lung disease (ILD) and is the most significant reason for mortality in most forms of ILDs. Knowledge of outcome predictors that can be assessed early after intensive care unit (ICU) admission would help guide the use of specific treatments. The present study attempts to identify the baseline characteristics of ILD patients admitted due to acute respiratory failure to ICU and to evaluate the cause of acute respiratory failure in these patients, management, and the outcomes. Materials and Methods: An observational cohort study was carried out in a tertiary care center in North India on 50 previously diagnosed patients of ILD hospitalized due to acute respiratory failure between January and December 2022. All relevant clinical, investigational, and treatment data were collected from the hospital information system. Results: The baseline mean FVC and 6-min walk distance were lower for non-survivors. The baseline mean DLCO was significantly lower among non-survivors. Comparatively, the radiology pattern of both groups showed that the usual interstitial pneumonia (UIP) pattern was associated with highest mortality. However, this difference was not statistically significant. Mortality was higher in those with lower PaO2/FiO2 ratio than among the survivors. Sputum culture positivity had a statistically significant impact on mortality. The mean hospital stay time was considerably higher in patients with idiopathic pulmonary fibrosis (IPF) and in patients with Type 2 respiratory failure. Conclusion: Baseline lung function tests, comorbidities, and exacerbating factors are invaluable in predicting the clinical outcomes. It is essential to perform all the diagnostic examinations at the earliest to ensure prompt initiation of the most appropriate therapy and lower hospital mortality. Distinguishing those patients who have a known cause for their ILD from those who do not was found to be crucial for deciding the most appropriate management.

Debunking the GAMLSS Myth: Simplicity Reigns in Pulmonary Function Diagnostics

RationaleCurrent technical standards advocate using Generalized, Additive Models of Location, Scale, and Shape (GAMLSS) for lung function reference equations. These equations are complicated and require supplementary spline tables. Objective(1) To demonstrate that segmented (piecewise) linear regression (SLR) yields similar prediction accuracies as GAMLSS in pulmonary function diagnostics. (2) To determine the agreement between both SLR and GAMLSS. MethodsThe NHANES 2007-2012 database was utilized to construct spirometric reference equations for FEV1, FVC, and FEV1/FVC using both SLR and GAMLSS modeling techniques. K-fold cross-validation was used to provide the 95% confidence interval (CI) of the root-mean-square error (RMSE) as indicators of prediction accuracy. Additionally, agreement was assessed between the two modeling techniques in classifying spirometric patterns (standard, airflow obstruction, restrictive, or mixed disorder) using an unweighted kappa statistic. ResultsThe RMSE values for FEV1, FVC, and FEV1/FVC and correlation coefficients between predicted values and test data were similar between the two techniques. Agreement in classifying spirometric patterns between the two techniques ranged from 0.78 to 0.80 (95% CI). ConclusionsThe findings suggest that simple linear regression for FEV1/FVC and SLR for FEV1 and FVC offer prediction accuracies on par with GAMLSS while being more straightforward, parsimonious, and accessible to a broader audience in the field of pulmonary function diagnostics.