Prevalence, stability, and clinical significance of an isolated low FEV1 spirometry pattern in children.

OBJECTIVES: In adults, an isolated low FEV1 pattern (an FEV1 below the lower limit of normal with a preserved FVC and FEV1/FVC) has been associated with the risk of developing airway obstruction. Our objective was to examine the prevalence, stability, and clinical significance of an isolated low FEV1 pattern in the pediatric population. METHODS: We conducted a retrospective study of spirometries from children ages 6-21 years and categorized tests into spirometry patterns according to published guidelines and recent literature. In a subgroup of tests with an isolated low FEV1 pattern, we evaluated spirometry technique. We also examined the association of having a test with an isolated low FEV1 pattern with clinical markers of disease severity in a subgroup of children with cystic fibrosis (CF). RESULTS: The isolated low FEV1 pattern was uncommon across the 29,979 tests included (n = 645 [2%]). In the 263 children with an isolated low FEV1 pattern who had a follow-up test performed, the most frequent spirometry pattern at last test was normal (n = 123 [47%]). A primary diagnosis of CF was associated with increased odds of having at least one test with an isolated low FEV1 pattern (OR = 8.37, 95% CI = 4.70-15.96, p < .001). The spirometry quality in a subgroup of tests with an isolated low FEV1 pattern (n = 50) was satisfactory. In the subgroup of children with CF (n = 102), those who had a test with an isolated low FEV1 pattern had higher odds of using oral antibiotics in the last 12 months than those who had a normal pattern (OR = 3.50, 95% CI = 1.15-10.63, p = .03). CONCLUSIONS: The isolated low FEV1 pattern can occur repeatedly over time, usually transitions to a normal pattern, is not due to a poor spirometry technique, and could be clinically relevant in children with chronic lung diseases.

Predicting delayed extubation and transfer to the intensive care unit in children undergoing posterior fusion surgery for scoliosis : A retrospective observational study.

BACKGROUND: Delayed extubation and transfer to the intensive care unit (ICU) in children undergoing major scoliosis surgery may increase postoperative complications, prolong hospital stay, and increase medical expenses; however, whether a child will require delayed extubation or transfer to the ICU after scoliosis orthopedic surgery is not fully understood. In this study, we reviewed the risk factors for delayed extubation and transfer to the ICU after scoliosis orthopedic surgery in children. METHOD: The electronic medical records of pediatric patients (≤ 18 years) who underwent posterior spinal fusion surgery between January 2018 and November 2021 were reviewed and analyzed. Patient characteristics (age, sex, body mass index, American Society of Anesthesiologists, ASA, grade, preoperative lung function, and congenital heart disease), preoperative Cobb angle, scoliosis type, correction rate, vertebral fusion segments, pedicle screws, surgical osteotomy, intraoperative bleeding, intraoperative allogeneic transfusion, intraoperative hemoglobin changes, intraoperative mean arterial pressure changes, intraoperative tidal volume (ml/kg predicted body weight), surgical time, postoperative extubation, and transfer to the ICU were collected. The primary outcomes were delayed extubation and transfer to the ICU. Multivariate logistic regression models were used to determine the risk factors for delayed extubation and ICU transfer. RESULTS: A total of 246 children who satisfied the inclusion criteria were enrolled in this study, of whom 23 (9.3%) had delayed extubation and 81 (32.9%) were transferred to the ICU after surgery. High ASA grade (odds ratio [OR] 5.42; 95% confidence interval [CI] 1.49-19.78; p = 0.010), high Cobb angle (OR 1.04; 95% CI 1.02-1.07; p < 0.001), moderate to severe pulmonary dysfunction (OR 10.9; 95% CI 2.00-59.08; p = 0.006) and prolonged surgical time (OR 1.01; 95% CI 1.00-1.03; p = 0.040) were risk factors for delayed extubation. A high Cobb angle (OR 1.02; 95% CI 1.01-1.04; p = 0.004), high intraoperative bleeding volume (OR 1.06; 95% CI 1.03-1.10; p = 0.001), allogeneic transfusion (OR 3.30; 95% CI 1.24-8.83; p = 0.017) and neuromuscular scoliosis (OR 5.38; 95% CI 1.59-18.25; p = 0.007) were risk factors for transfer to the ICU. A high Cobb angle was a risk factor for both delayed extubation and ICU transfer. Age, sex, body mass index, number of vertebral fusion segments, correction rate, and intraoperative tidal volume were not associated with delayed postoperative extubation and ICU transfer. CONCLUSION: The most common risk factor for delayed extubation and ICU transfer in pediatric patients who underwent posterior spinal fusion was a high Cobb angle. Determining risk factors for a poor prognosis may help optimize perioperative respiratory management strategies and planning of postoperative care for children undergoing complicated spinal surgery.

Assessing pulmonary function in ALS using electrical impedance tomography.

Objective: We sought to determine whether thoracic electrical impedance tomography (EIT) could characterize pulmonary function in amyotrophic lateral sclerosis (ALS) patients, including those with facial weakness. Thoracic EIT is a noninvasive, technology in which a multi-electrode belt is placed across the chest, producing real-time impedance imaging of the chest during breathing. Methods: We enrolled 32 ALS patients and 32 age- and sex-matched healthy controls (HCs) without underlying lung disease. All participants had EIT measurements performed simultaneously with standard pulmonary function tests (PFTs), including slow and forced vital capacity (SVC and FVC) in upright and supine positions and maximal inspiratory and expiratory pressures (MIPs and MEPs, respectively). Intraclass correlation coefficients (ICCs) were calculated to assess the immediate reproducibility of EIT measurements and Pearson's correlations were used to explore the relationships between EIT and PFT values. Results: Data from 30 ALS patients and 27 HCs were analyzed. Immediate upright SVC reproducibility was very high (ICC 0.98). Correlations were generally strongest between EIT and spirometry measures, with R values ranging from 0.64 to 0.82 (p < 0.001) in the ALS cohort. There were less robust correlations between EIT values and both MIPs and MEPs in the ALS patients, with R values ranging from 0.33 to 0.44. There was no significant difference for patients with and without facial weakness. There were no reported adverse events. Conclusion: EIT-based pulmonary measures hold the promise of providing an alternative approach for lung function assessment in ALS patients. Based on these early results, further development and study of this technology are warranted.

Lymphangioleiomyomatosis and pregnancy: a mini-review.

Lymphangioleiomyomatosis(LAM) is a slow progressive, rare cystic lung disease in women of reproductive age, associated with infiltration of the lung by atypical smooth muscle like cells, leading to the cystic destruction of the lung parenchyma. As LAM exclusively affects women of childbearing age, it can arise or exacerbate during pregnancy. Many patients with LAM are discouraged from pregnancy, although there is not much objective evidence effect on fertility. Patients diagnosed with LAM during pregnancy experience worse outcomes, so the safety of pregnancy is a vexing problem. What was worse, treatment strategies are limited on the effects of LAM on pregnancy outcomes. Pregnancy could be considered in LAM patients. Successful delivery in women with LAM depends on the condition of the LAM, which is in turn dependent on obstetricians and respiratory physicians. In this review, we describe the epidemiology, pathogenesis, diagnosis, clinical features and the treatment strategies of LAM during pregnancy.

Experiences of systemic sclerosis patients with home monitoring of their pulmonary function: a qualitative study.

Objective: To evaluate the experiences, perceived benefits and disadvantages of home monitoring of pulmonary function in SSc patients with interstitial lung disease (ILD). Methods: Semistructured interviews were conducted among SSc-ILD patients who used the home monitoring application of pulmonary function for at least 3 months. In our program, patients are instructed to perform home spirometry weekly at fixed time points using a mobile application with results being directly visible for patients and physicians. Audiotapes of the interviews were transcribed verbatim and analysed using inductive thematic analysis after performing a member check. Results: A total of 13 patients were interviewed, with a median age of 58 years (range 36-75) and a median experience with home monitoring of 12 months (range 3-12). We identified four major themes, including routine of telemonitoring, impact of telemonitoring, trust in telemonitoring and implementation in regular healthcare. Overall, patients found performing home spirometry to be feasible. Major perceived benefits of performing home spirometry are an increase in patient empowerment, better understanding of the disease course and a reduction in hospital visits, whereas identified disadvantages are an emotional burden of telemonitoring, heightened awareness of illness, doubts about its validity and the need for digital competencies. All patients expressed their willingness to continue, although some patients emphasized the need for face-to-face visits. Conclusion: Telemonitoring of pulmonary function is accepted by SSc-ILD patients with the perceived benefits outweighing the disadvantages. Adopting a patient-centred strategy that considers individual factors and addresses concerns proactively is warranted to successfully implement home spirometry.

(F)utility of preoperative pulmonary function testing in pectus excavatum to assess severity.

PURPOSE: The utility of pulmonary function testing (PFT) in pectus excavatum (PE) has been subject to debate. Although some evidence shows improvement from preoperative to postoperative values, the clinical significance is uncertain. A high failure-to-completion rate for operative PFT (48%) was identified in our large institutional cohort. With such a high non-completion rate, we questioned the overall utility of PFT in the preoperative assessment of PE and sought to evaluate if other measures of PE severity or cardiopulmonary function could explain this finding. METHODS: Demographics, clinical findings, and results from cardiac MRI, PFT (spirometry and plethysmography), and cardiopulmonary exercise tests (CPET) were reviewed in 270 patients with PE evaluated preoperatively between 2015 and 2018. Regression modeling was used to measure associations between PFT completion and cardiopulmonary function. RESULTS: There were no differences in demographics, symptoms, connective tissue disorders, or multiple indices of pectus severity and cardiac deformation in PFT completers versus non-completers. While regression analysis revealed higher RVEF, LVEF, and LVEF-Z scores, lower RV-ESV/BSA, LV-ESV/BSA, and LV-ESV/BSA-Z scores, and abnormal breathing reserve in PFT completers vs. non-completers, these findings were not consistent across continuous and binary analyses. CONCLUSIONS: We found that PFT completers were not significantly different from non-completers in most structural and functional measures of pectus deformity and cardiopulmonary function. Inability to complete PFT is not an indicator of pectus severity.

A Community-Based Cross-Sectional Study on Respiratory Health and Spirometry-Assessed Pulmonary Function Among Textile Workers in Tamil Nadu, India.

Introduction The textile industry is one of the largest economic activities. Still, the laborers involved in it are exposed to various health-damaging air pollutants, putting them at risk of health issues including morbidities of the respiratory system. Therefore, this study aimed to assess the pulmonary function parameters of the workers involved in textile manufacturing-related jobs. Methodology A cross-sectional study was carried out among adult individuals who had been working in textile manufacturing-related jobs as their main work. The details such as sociodemographic, clinical, workplace conditions, and smoking habits were collected, as well as chest auscultation and lung spirometry using a hand-held spirometer. The participants who had normal and abnormal lung function patterns were statistically analyzed for potential influencing factors. Results The findings of the study conducted from 95 eligible participants identified that the pulmonary function parameters assessed by spirometry were in the abnormal range among 84 (88%) participants. Around 72 (82%) of them had a restrictive pattern, and six (6%) had both restrictive and obstructive (mixed) patterns of lung disease. Smokers and those who lacked cross-ventilation and/or fresh source of air in the workplace were more likely to have abnormal lung function. Participants who had their workplace and residence as same had significantly 6.44 (95% CI: 1.24, 33.36) times higher odds of having abnormal lung function in spirometry. Conclusion As workers involved in household-run textile manufacturing jobs are found to be at a higher risk of developing abnormal lung function, using personal protective equipment, following occupational safety measures, and improving the working environment to acceptable standards are essential to safeguard the respiratory health of laborers in such unorganized sectors.

Effect of postoperative intermittent boluses of subcostal quadratus lumborum block on pulmonary function recovery and analgesia after gastrectomy: a randomized controlled clinical trial.

BACKGROUND: Following the gastrectomy, the reduction in pulmonary function is partly attributed to postoperative pain. Subcostal quadratus lumborum block (QLB) has recently emerged as a promising component in multimodal analgesia. We aimed to assess the impact of intermittent boluses of subcostal QLB on pulmonary function recovery and analgesic efficacy after gastrectomy. METHODS: Sixty patients scheduled for gastrectomy were randomly assigned to either control group (multimodal analgesia) or intervention group (intermittent boluses of subcostal QLB plus multimodal analgesia). Two primary outcomes included the preservation of forced expiratory volume in the first second (FEV1) and the pain scores (0-10 cm visual analog score) on coughing 24 h postoperatively. We assessed the pulmonary function parameters, pain score, morphine consumption and number of rescue analgesia at a 24-h interval up to 72 h (Day1, Day2, Day3 respectively) as secondary outcomes. RESULTS: 59 patients were analyzed in a modified intention-to-treat set. The preservation of FEV1 (median difference: 4.0%, 97.5% CI: -5.7 to 14.9, P = 0.332) and pain scores on coughing (mean difference: 0.0 cm, 97.5% CI: -1.1 to 1.2, P = 0.924) did not differ significantly between two groups. In the intervention group, the recovery of forced vital capacity (FVC) was faster 72 h after surgery (interaction effect of group*(Day3-Day0): estimated effect (ß) =0.30 L, standard error (SE) =0.13, P = 0.025), pain scores at rest were lower in the first 3 days (interaction effect of group*(Day1-Day0): ß = - 0.8 cm, SE = 0.4, P = 0.035; interaction effect of group*(Day2-Day0): ß = - 1.0 cm, SE = 0.4, P = 0.014; and interaction effect of group*(Day3-Day0): ß = - 1.0 cm, SE = 0.4, P values = 0.009 respectively), intravenous morphine consumption was lower during 0-24 h (median difference: -3 mg, 95% CI -6 to -1, P = 0.014) and in total 72 h (median difference: -5 mg, 95% CI -10 to -1, P = 0.019), and the numbers of rescue analgesia was fewer during 24-48 h (median difference: 0, 95% CI 0 to 0, P = 0.043). Other outcomes didn't show statistical differences. CONCLUSION: Postoperative intermittent boluses of subcostal QLB did not confer advantages in terms of the preservation of FEV1 or pain scores on coughing 24 h after gastrectomy. However, notable effects were observed in analgesia at rest and FVC recovery.

Exploring the adverse effect of fine particulate matter (PM2.5) on wildland firefighters' pulmonary function and DNA damage.

Chiang Mai encounters severe pollution during the wildfire season. Wildland firefighters encounter various hazards while engaged in fire suppression operations, which encompass significant exposure to elevated concentrations of air pollutants resulting from combustion, especially particulate matter. The adverse effects of wildfire smoke on respiratory health are a significant concern. The objective of this study was to examine the potential adverse effects of PM2.5 exposure on the respiratory function and DNA damage of wildland firefighters. This prospective cohort study conducted in Chiang Mai from January to May 2022 planned to evaluate the health status of wildland firefighters during the pre-peak, peak, and post-peak ambient air pollution seasons. The measurement of PM2.5 was done at every forest fire station, as well as utilizing data from the Pollution Control Department. Participants received general health examinations, spirometry evaluations, and blood tests for DNA damage analysis. Pair t-tests and multiple regression models were used to examine the connection between pulmonary function parameters (FVC, FEV1) and PM2.5 concentration, with a significance level of P < 0.05. Thirty-three peak-season and twenty-one post-peak-season participants were enrolled. Four pre-peak-season wildland firefighters had FVC and FEV1 declines of > 15%. Multiple regression analysis showed a negative association between PM2.5 exposure and FVC% predicted (- 2.81%, 95% CI - 5.27 to - 0.34%, P = 0.027) and a marginally significant negative correlation with FVC (- 114.38 ml, 95% CI - 230.36 to 1.59 ml, P = 0.053). The remaining pulmonary measures showed a statistically insignificant decline. There were no significant changes in DNA damage detected. Wildland firefighters suffered a significant decline in pulmonary function associated with PM2.5 exposure. Spirometry is crucial for monitoring and promptly identifying respiratory issues that occur during wildfire seasons. Further research is recommended to explore DNA damage alterations and their potential association with PM2.5.

The effect of goal-directed crystalloid versus colloid administration on postoperative spirometry parameters: a substudy of a randomized controlled clinical trial.

BACKGROUND: Pulmonary function is impaired after major abdominal surgery and might be less impaired by restrictive fluid administration. Under the assumption of a fluid-sparing effect of colloids, we tested the hypothesis that an intraoperative colloid-based goal-directed fluid management strategy impairs postoperative pulmonary function parameters less compared to goal-directed crystalloid administration. METHODS: We performed a preplanned, single-center substudy within a recently published trial evaluating the effect of goal-directed crystalloids versus colloids on a composite of major complications. Sixty patients undergoing major open abdominal surgery were randomized to Doppler-guided intraoperative fluid replacement therapy with lactated Ringer's solution (n = 31) or unbalanced 6% hydroxyethyl starch 130/0.4 (n = 29). A blinded investigator performed bedside spirometry (Spirobank-G, Medical International Research, Rome, Italy) preoperatively as well as 6, 24, and 48 h postoperatively. RESULTS: Median total intraoperative fluid requirements were significantly higher during crystalloid administration compared to patients receiving colloids (4567 ml vs. 3044 ml, p = 0.01). Six hours after surgery, pulmonary function parameters did not differ significantly between the crystalloid - and the colloid group: forced vital capacity (FVC): 1.6 l (1.2-2 l) vs. 1.9 l (1.5-2.4 l), p = 0.15; forced expiratory volume in 1 second (FEV1): 1.1 l (0.9-1.6 l) vs. 1.4 l (1.2-1.7 l), p = 0.18; and peak expiratory flow (PEF): 2 l.sec-1 (1.5 - 3.6 l.sec -1) vs. 2.3 l.sec -1 (1.8 - 3.4 l.sec -1), p = 0.23. Moreover, postoperative longitudinal time × group interactions of FVC, FEV1, and PEF between 6 and 48 postoperative hours did not differ significantly. CONCLUSION: Postoperative pulmonary function parameters were similarly impaired in patients receiving goal-directed crystalloid administration as compared to goal-directed colloid administration during open abdominal surgery. TRIAL REGISTRATION: ClinicalTrials.gov ( NCT00517127 , registered on August 16, 2007) and EudraCT (2005-004602-86).

Chronic rhinosinusitis possibly associated with decreased lung function in chronic cough patients.

OBJECTIVES: The purpose of this study is to investigate the lung function in Chronic Rhinosinusitis (CRS) patients with Chronic Cough (CC). METHODS: A total of 1413 CC patients were retrospectively screened and 109 CRS patients with CC were enrolled. Lung function, Lund-Mackay Computed Tomography (CT) score, smoking status, peripheral blood eosinophil count, and immunoglobulin E concentration in serum samples, and Sino-Nasal Outcome Test were examined. Normal control subjects are also recruited. RESULTS: The Forced Expiratory Volume in 1 second (FEV1.0), Percent Predicted FEV1.0, and FEV1.0/Forced Vital Capacity (FVC) ratio in the patients were significantly low as compared with the control subjects. The FEV1.0/FVC ratio was negatively correlated with the Lund-Mackay CT scores of the patients with a high CT score. CONCLUSIONS: The CRS patients with CC should be investigated with lung function. In addition, the multidisciplinary evaluation including a pulmonologist is needed to manage the CRS patients with CC. LEVEL OF EVIDENCE: Level 4.

[National Survey on the Activity of Lung Function Laboratories. Effects During the SARS-COV-2 Pandemic]. / Encuesta sobre la actividad de los laboratorios de función pulmonar. Efectos durante la pandemia por SARS-CoV-2.

Introduction: Following the SARS-CoV-2 pandemic in March 2020, pulmonary function testing (PFT) laboratories underwent a transformation, with a reduction in the number of tests or closure in some cases. The aim of this work was to know the activity of PFT in Spain and the modification of this activity due to the pandemic. Material and methods: A protocolised survey was carried out to members of the PFT laboratories through the Spanish Society of Pneumology and Thoracic Surgery (SEPAR). Results: Thirty-nine hospitals in Spain responded. The pulmonary function tests most frequently performed in the PFT laboratories were forced spirometry with bronchodilator test (100%), body plethysmography (97.4%), CO transfer capacity (97.4%), respiratory muscle strength measured in the mouth (97.4%), 6-minute walking test (94.7%), measurement of exhaled fraction of nitric oxide (92.3%) and incremental exercise test (71.8%).The pandemic led to a significant decrease in the number of tests (35.4%) during 2020 with subsequent recovery in 2021, without reaching pre-pandemic values.The most important changes were increased examination times, working with personal protective equipment and ventilation of the rooms. The performance of the nasopharyngeal swab for SARS-CoV2 testing prior to the tests was not homogeneous in the PFT laboratories. Conclusions: Most hospitals are sufficiently equipped to perform the most common pulmonary function tests. The pandemic resulted in a loss of activity in all hospitals.

Association of Pulmonary Function Test Abnormalities and Quality-of-Life Measures after COVID-19 Infection.

BACKGROUND: Long-COVID is a multisystem disease that can lead to significant impairments in health-related quality of life (HRQoL). Following COVID-19 infection, abnormalities on pulmonary function tests (PFT) are common. The primary aim of this study is to evaluate for any correlation between PFT abnormalities and impairment in HRQoL scores following COVID-19 infection. METHODS: This is an analysis of a prospective cohort of patients in Louisville, KY who were infected with COVID-19. Data collected included demographics, past medical history, laboratory tests, PFTs, and several HRQoL questionnaires such as the EuroQol 5 Dimension HRQoL questionnaire (EQ-5D-5L), Generalized Anxiety Disorder 7 (GAD-7), Patient Health Questionnaire (PHQ-9), and Posttraumatic stress disorder checklist for DSM-5 (PCL-5). Descriptive statistics were performed, comparing PFTs (normal vs abnormal) and time since COVID-19 infection (3- vs 6- vs ≥ 12 months). RESULTS: There were no significant differences in FEV1, FVC, or the percentage of patients with abnormal PFTs over time after COVID-19 infection. Following COVID-19, patients with normal PFTs had worse impairment in mobility HRQoL scores and change in GAD-7 scores over time. There were no differences over time in any of the HRQoL scores among patients with abnormal PFTs. CONCLUSIONS: Among patients with an abnormal PFT, there was no temporal association with HRQoL scores as measured by EQ-5D-5L, GAD-7, PHQ-9, and PCL-5. Among patients with a normal PFT, mobility impairment and anxiety may be associated with COVID-19 infection. Following COVID-19 infection, impairment in HRQoL scores is not completely explained by the presence of abnormalities on spirometry.

Assessment of pulmonary function and respiratory symptoms among INDIAN textile sizing mill workers.

BACKGROUND: Textile-sizing mill workers are exposed to various hazards in the sizing units during their working hours and are at risk of acquiring lung impairments due to the usage of sizing chemicals in the sizing process. OBJECTIVE: The main aim of this study is to assess the influence of cotton dust and sizing agents on lung function and breathing difficulties among Indian textile sizing mill workers. METHODS: This cross-sectional study was carried out at a textile-sizing mill from August 2022 to September 2022. A modified questionnaire based American Thoracic Society's standard was used to assess respiratory symptoms among sizing mill workers and the pulmonary function test was conducted Spirometry. The chi-square test was used to find the difference between respiratory symptoms and the t-test was used to find the difference between spirometric parameters. RESULTS: Textile sizing mill workers showed significant (P <  0.0001) decline in peak expiratory flow rate, forced vital capacity (FVC), ratio of FEV1 and forced vital capacity, and forced expiratory volume in 1 s (FEV1). There was an association between symptoms and duration of exposure to pulmonary abnormality. Sizing mill workers showed a significant decline in lung functions and an increase in pulmonary symptoms. As the service duration of exposure in terms of years increased, respiratory symptoms increased and spirometric abnormality also increased. CONCLUSION: This study confirms that sizing agents such as polyvinyl alcohol (PVA), emulsifier, wax, carboxymethyl cellulose (CMC), and starch used in sizing mills are also responsible for respiratory illness and lung impairment among textile workers.

Longitudinal changes in lung function following post-9/11 military deployment in symptomatic veterans.

RATIONALE: Exposure to burn pit smoke, desert and combat dust, and diesel exhaust during military deployment to Southwest Asia and Afghanistan (SWA) can cause deployment-related respiratory diseases (DRRDs) and may confer risk for worsening lung function after return. METHODS: Study subjects were SWA-deployed veterans who underwent occupational lung disease evaluation (n=219). We assessed differences in lung function by deployment exposures and DRRD diagnoses. We used linear mixed models to assess changes in lung function over time. RESULTS: Most symptomatic veterans reported high intensity deployment exposure to diesel exhaust and burn pit particulates but had normal post-deployment spirometry. The most common DRRDs were deployment-related distal lung disease involving small airways (DDLD, 41%), deployment-related asthma (DRA, 13%), or both DRA/DDLD (24%). Those with both DDLD/DRA had the lowest estimated mean spirometry measurements five years following first deployment. Among those with DDLD alone, spirometry measurements declined annually, adjusting for age, sex, height, weight, family history of lung disease, and smoking. In this group, the forced expiratory volume in the first second/forced vital capacity (FEV1/FVC) ratio declined 0.2% per year. Those with more intense inhalational exposure had more abnormal lung function. We found significantly lower estimated FVC and total lung capacity five years following deployment among active duty participants (n=173) compared to those in the reserves (n=26). CONCLUSIONS: More intense inhalational exposures were linked with lower post-deployment lung function. Those with distal lung disease (DDLD) experienced significant longitudinal decline in FEV1/FVC ratio, but other DRRD diagnosis groups did not.

Impact of 1-Year Supplementation with High-Rich Docosahexaenoic Acid (DHA) on Clinical Variables and Inflammatory Biomarkers in Pediatric Cystic Fibrosis: A Randomized Double-Blind Controlled Trial.

A randomized, double-blind, and placebo-controlled study was conducted to assess the effect of dietary supplementation with high-rich docosahexaenoic acid (DHA) (Tridocosahexanoin-AOX® 70%) at 50 mg/kg/day in pediatric patients with cystic fibrosis (CF) as compared with placebo. The duration of supplementation was 12 months. A total of 22 patients were included, with 11 in the DHA group and 11 in the placebo group. The mean age was 11.7 years. The outcome variables were pulmonary function, exacerbations, sputum cellularity, inflammatory biomarkers in sputum and peripheral blood, and anthropometric variables. In the DHA group, there was a significant increase in FVC (p = 0.004) and FVE1 expressed in liters (p = 0.044) as compared with placebo, and a lower median number of exacerbations (1 vs. 2). Differences in sputum cellularity (predominantly neutrophilic), neutrophilic elastase, and sputum and serum concentrations of resolvin D1 (RvD1), interleukin (IL)-8 (IL-8), and tumor necrosis factor alpha (TNF-α) between the study groups were not found. Significant increases in weight and height were also observed among DHA-supplemented patients. The administration of the study product was safe and well tolerated. In summary, the use of a highly concentrated DHA supplement for 1 year as compared with placebo improved pulmonary function and reduced exacerbations in pediatric CF.

Persistence of Diffusion Capacity Impairment and Its Relationship with Dyspnea 12 Months after Hospitalization for COVID-19.

Background: Dyspnea is a common persistent symptom after acute coronavirus disease 2019 illness (COVID-19). One potential explanation for post-COVID-19 dyspnea is a reduction in diffusion capacity. This longitudinal study investigated diffusion capacity and its relationship with dyspnea on exertion in individuals previously hospitalized with COVID-19. Methods: Eligible participants had been hospitalized for the treatment of acute COVID-19 and were assessed at 6 weeks, 6 months, and 12 months after discharge. Pulmonary function testing, diffusion capacity of carbon monoxide (DLCO), blood gas analysis and the level of dyspnea (Borg scale; before and after a 6 min walk test [6 MWT]) were performed. Participants were divided into subgroups based on the presence or absence of dyspnea during the 6 MWT at 12 months after hospitalization. Results: Seventy-two participants (twenty-two female, mean age 59.8 ± 13.5 years) were included. At 12 months after discharge, 41/72 participants (57%) had DLCO below the lower limit of normal and 56/72 (78%) had DLCO < 80% of the predicted value. Individuals with exertional dyspnea had significantly lower DLCO than those without exertional dyspnea (p = 0.001). In participants with DLCO data being available at three timepoints over 12 months (baseline, 6 months, and 12 months) after discharge (n = 25), DLCO improved between 6 weeks and 6 months after hospital discharge, but not thereafter (p = 0.017). Conclusions: About 2/3 of the post-COVID individuals in this study had impaired diffusion capacity at 12 months after hospital discharge. There was an association between persisting dyspnea on exertion and significantly reduced DLCO. Impaired diffusion capacity improved over the first 6 months after hospitalization but not thereafter.

Long-term outcomes of survivors with influenza A H1N1 virus-induced severe pneumonia and ARDS: a single-center prospective cohort study.

Introduction: Systematic evaluation of long-term outcomes in survivors of H1N1 is still lacking. This study aimed to characterize long-term outcomes of severe H1N1-induced pneumonia and acute respiratory distress syndrome (ARDS). Method: This was a single-center, prospective, cohort study. Survivors were followed up for four times after discharge from intensive care unit (ICU) by lung high-resolution computed tomography (HRCT), pulmonary function assessment, 6-minute walk test (6MWT), and SF-36 instrument. Result: A total of 60 survivors of H1N1-induced pneumonia and ARDS were followed up for four times. The carbon monoxide at single breath (DLCO) of predicted values and the 6MWT results didn't continue improving after 3 months. Health-related quality of life didn't change during the 12 months after ICU discharge. Reticulation or interlobular septal thickening on HRCT did not begin to improve significantly until the 12-month follow-up. The DLCO of predicted values showed negative correlation with the severity degree of primary disease and reticulation or interlobular septal thickening, and a positive correlation with physical functioning. The DLCO of predicted values and reticulation or interlobular septal thickening both correlated with the highest tidal volume during mechanical ventilation. Levels of fibrogenic cytokines had a positive correlation with reticulation or interlobular septal thickening. Conclusion: The improvements in pulmonary function and exercise capacity, imaging, and health-related quality of life had different time phase and impact on each other during 12 months of follow-up. Long-term outcomes of pulmonary fibrosis might be related to the lung injury and excessive lung fibroproliferation at the early stage during ICU admission.

Application of the ERS/ATS Spirometry Standards and Race-Neutral Equations in the COPDGene Study.

RATIONALE: The European Respiratory Society (ERS) and the American Thoracic Society (ATS) recommend using z-scores, and the ATS has recommended using Global Lung Initiative (GLI)- "Global" race-neutral reference equations for spirometry interpretation. However, these recommendations have been variably implemented and the impact has not been widely assessed, both in clinical and research settings. OBJECTIVES: We evaluated the ERS/ATS airflow obstruction severity classification. METHODS: In the COPDGene Study (n = 10,108), airflow obstruction has been defined as a forced expiratory volume in one second to forced vital capacity (FEV1/FVC) ratio <0.70, with spirometry severity graded from class 1 to 4 based on race-specific percent predicted (pp) FEV1 cut-points as recommended by the Global Initiative for Chronic Obstructive Lung Disease (GOLD). We compared the GOLD approach, using NHANES III race-specific equations, to the application of GLI-Global equations using the ERS/ATS definition of airflow obstruction as FEV1/FVC ratio < lower limit of normal (LLN) and z-FEV1 cut-points of -1.645, -2.5, and -4 ("zGLI Global"). We tested the four-tier severity scheme for association with COPD outcomes. MEASUREMENTS AND MAIN RESULTS: The lowest agreement between ERS/ATS with zGLI Global and the GOLD classification was observed in individuals with milder disease (56.9% and 42.5% in GOLD 1 and 2) and race was a major determinant of redistribution. After adjustment for relevant covariates, zGLI Global distinguished all-cause mortality risk between normal spirometry and the first grade of COPD (Hazard Ratio 1.23, 95% CI 1.04-1.44, p=0.014), and showed a linear increase in exacerbation rates with increasing disease severity, in comparison to GOLD. CONCLUSIONS: The zGLI Global severity classification outperformed GOLD in the discrimination of survival, exacerbations, and imaging characteristics.

Preoperative DLCO predicts severe early complications after liver transplantation.

BACKGROUND: Severe early complications are common after liver transplantation (LT) and are a key determinant of LT-related morbidity and mortality. The aim of this study was to assess whether lung function measured in the pre-operative period predicted complicated outcomes in the first month after LT. MATERIAL AND METHODS: Patients with mild-to-moderate liver disease (Model for End stage Liver Disease-MELD score≤30) who underwent LT between October 2015 and May 2020 in a single centre were retrospectively included. The primary endpoint was the occurrence of severe early complications after LT defined by mechanical ventilation duration > 2 days or length of ICU stay > 7 days or reintubation or death < 1 month after LT. RESULTS: One hundred and twenty patients were included (age 59 [53-64] years, 72 % men). Forty patients (33 %) had early complications after LT. Measured and%predicted hemoglobin-corrected lung transfer capacity for carbon monoxide (DLCOc) were significantly lower in patients with severe early complications after LT. DLCOc was the only variable that associated independently with severe early complications by multivariate analysis. DLCOc under 16.3 ml.min-1.mmHg-1 predicted respiratory complications with a sensitivity of 67.5 % and a specificity of 62.9 %. DLCOc%pred under 61.5 % had a sensitivity of 56.8 % and a specificity of 72 %. DLCOc independently associated with forced vital capacity (FVC), pulmonary emphysema, and the muscle mass index. CONCLUSION: A decrease in DLCOc indicated an increased risk of severe early complications after LT.